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Nair, Smita Kesavan

Overview:

I have 22 years of experience in the field of cancer vaccines and immunotherapy and I am an accomplished T cell immunologist. Laboratory website:
https://surgery.duke.edu/immunology-inflammation-immunotherapy-laborator...

Current projects in the Nair Laboratory:
1] Dendritic cell vaccines using tumor-antigen encoding RNA (mRNA, total tumor RNA, amplified tumor mRNA)
2] Local immune receptor modulation using mRNA that encodes for antibodies, receptor-ligands, cytokines, chemokines and toll-like receptors (current target list: CTLA4, GITR, PD1, TIM3, LAG3, OX40 and 41BB)
3] Combination therapies for cancer: cytotoxic therapy (radiation, chemo and oncolytic poliovirus therapy) with dendritic cell-based vaccines and immune checkpoint blockade
4] Adoptive T cell therapy using tumor RNA-transfected dendritic cells to expand tumor-specific T cells ex vivo
5] Adoptive T cell therapy using PSMA CAR (chimeric antigen receptor) RNA-transfected T cells
6] Direct injection of tumor antigen encoding RNA (targeting antigens to dendric cells in vivo using nanoparticles and aptamers)

Positions:

Professor in Surgery

Surgery, Surgical Sciences
School of Medicine

Professor in Pathology

Pathology
School of Medicine

Member of the Duke Cancer Institute

Duke Cancer Institute
School of Medicine

Education:

Ph.D. 1993

Ph.D. — University of Tennessee at Knoxville

News:

Can a Modified Poliovirus Fight Advanced Prostate Cancer Too?

August 26, 2015 — Duke Translational Medicine Institute

Lab Develops Cheaper, Faster Cancer Vaccine

August 08, 2014 — Duke Research Blog

Grants:

Oncolytic Polovirus, Immunotoxin, and Checkpoint Inhibitor Therapy of Gliomas

Administered By
Pathology
AwardedBy
National Institutes of Health
Role
Co Investigator
Start Date
August 01, 2015
End Date
July 31, 2022

CCL3 as a Developmental Therapeutic to Enhance Brain Tumor Therapy

Administered By
Neurosurgery
AwardedBy
National Institutes of Health
Role
Investigator
Start Date
December 01, 2016
End Date
November 30, 2021

Translational Research in Surgical Oncology

Administered By
Surgery, Surgical Sciences
AwardedBy
National Institutes of Health
Role
Mentor
Start Date
January 01, 2002
End Date
August 31, 2021

Regional Oncolytic Poliovirus Immunotherapy for Breast Cancer

Administered By
Surgery, Surgical Sciences
AwardedBy
Department of Defense
Role
Principal Investigator
Start Date
August 01, 2016
End Date
July 31, 2021

Melanoma-mediated Dendritic Cell Tolerization and Immune Evasion

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Co-Mentor
Start Date
August 04, 2015
End Date
July 31, 2020

Targeting DAMP-induced inflammation to prevent metastasis

Administered By
Surgery, Surgical Sciences
AwardedBy
Department of Defense
Role
Principal Investigator
Start Date
September 30, 2016
End Date
September 29, 2019

Therapeutic targeting of B7-H3 to reverse prostate cancer treatment resistance.

Administered By
Surgery, Urology
AwardedBy
Department of Defense
Role
Partnering PI
Start Date
September 15, 2016
End Date
September 14, 2019

Therapeutic Targeting of B7-H3 to Reverse Prostate Cancer Treatment Resistance

Administered By
Surgery, Surgical Sciences
AwardedBy
Department of Defense
Role
Principal Investigator
Start Date
September 15, 2016
End Date
September 14, 2019

Metabolic Reprogramming of Dendritic Cell-based Cancer Vaccines to Enhance Anti-Tumor Immunity

Administered By
Medicine, Medical Oncology
AwardedBy
Alliance for Cancer Gene Therapy
Role
Mentor
Start Date
June 10, 2016
End Date
June 09, 2019

Brain Tumor Targeting Using Tumor-Specific Neuroimmunology

Administered By
Neurosurgery
AwardedBy
National Institutes of Health
Role
Co Investigator
Start Date
September 15, 2014
End Date
May 31, 2018

Novel Immune Modulating Cellular Vaccine for Prostate Cancer Immunotherapy

Administered By
Surgery, Surgical Sciences
AwardedBy
Department of Defense
Role
Principal Investigator
Start Date
September 30, 2013
End Date
September 29, 2017

A clinically-relevant anti-CD27 agonist antibody as a vaccine adjuvant for brain tumor immunotherapy

Administered By
Neurosurgery
AwardedBy
National Institutes of Health
Role
Collaborator
Start Date
August 01, 2016
End Date
July 31, 2017

Enhancing dendritic cell migration to drive potent anti-tumor immune responses

Administered By
School of Medicine
AwardedBy
National Institutes of Health
Role
Mentor
Start Date
July 01, 2013
End Date
June 30, 2017

Using Aptamer Coated Nanoparticles Encapsulating Prostate Tumor Antigen Encoding mRNA to Target Dendritic Cells In Vivo

Administered By
Surgery, Surgical Sciences
AwardedBy
Department of Defense
Role
Principal Investigator
Start Date
September 01, 2012
End Date
August 31, 2015

RNA aptamers as cell surface receptor agonists and siRNA delivery agents

Administered By
Surgery, Surgical Sciences
AwardedBy
National Institutes of Health
Role
Co Investigator
Start Date
May 24, 2009
End Date
April 30, 2014

Cancer Immunotherapy w/In-Situ Maturated Dendritic cells

Administered By
Surgery, Surgical Sciences
AwardedBy
National Institutes of Health
Role
Co Investigator
Start Date
September 30, 2003
End Date
March 07, 2007

Cancer Immunotherapy Targeting Endothelial Antigens

Administered By
Surgery, Surgical Sciences
AwardedBy
National Institutes of Health
Role
Clinical Investigator
Start Date
July 01, 2003
End Date
August 31, 2006

Tumor RNA Transfected Dendritic Cell Vaccines

Administered By
Surgery, Surgical Sciences
AwardedBy
National Institutes of Health
Role
Research Associate
Start Date
April 01, 2000
End Date
March 31, 2005

Immunotherapy With Peptide Pulsed Dendritic Cells

Administered By
Surgery
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
September 30, 1996
End Date
August 31, 1999
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Publications:

Recombinant oncolytic poliovirus, PVSRIPO, has potent cytotoxic and innate inflammatory effects, mediating therapy in human breast and prostate cancer xenograft models.

Intratumoral inoculation of viruses with tumor-selective cytotoxicity may induce cancer cell death and, thereby, shrink neoplastic lesions. It is unlikely, however, that viral tumor cell killing alone could produce meaningful, durable clinical responses, as clinically suitable 'oncolytic' viruses are severely attenuated and their spread and propagation are opposed by host immunity. Thus, a more propitious event in this context is the innate antiviral response to intratumoral virus administration, in particular for recruiting durable adaptive immune effector responses. It may represent a double-edged sword, as innate immune activation may eliminate infected tumor cells early, intercept viral spread and block any meaningful therapeutic response. The innate response to viral infection of tumors may be very different from that in non-malignant target tissues, owing to the unusual composition/tissue properties of tumor stroma. In this work, we report investigations of the innate immune response to the oncolytic poliovirus recombinant, PVSRIPO, in two mouse xenotransplantation models for breast and prostate cancer. Our observations indicate short-term virus persistence in infected tumors and virus recovery indicative of modest intratumoral propagation and persistence. Yet, a powerful innate inflammatory response coincided with chemokine induction and myeloid cell infiltration into tumors that was, interestingly, dominated by neutrophils. The combined effect of PVSRIPO tumor infection and the innate response it elicits was significant tumor regression in both models.

Authors
Holl, EK; Brown, MC; Boczkowski, D; McNamara, MA; George, DJ; Bigner, DD; Gromeier, M; Nair, SK
MLA Citation
Holl, EK, Brown, MC, Boczkowski, D, McNamara, MA, George, DJ, Bigner, DD, Gromeier, M, and Nair, SK. "Recombinant oncolytic poliovirus, PVSRIPO, has potent cytotoxic and innate inflammatory effects, mediating therapy in human breast and prostate cancer xenograft models." Oncotarget 7.48 (November 2016): 79828-79841.
PMID
27806313
Source
epmc
Published In
Oncotarget
Volume
7
Issue
48
Publish Date
2016
Start Page
79828
End Page
79841
DOI
10.18632/oncotarget.12975

The RNAissance period.

The concept that RNA has played a major role in the evolution of life stems from the "RNA World" hypothesis. This role of RNA was not immediately appreciated. Similarly, the scientific community has just recently begun to recognize the true potential of RNA as the drug of choice for gene therapy, cellular reprogramming and vaccination. While it is perhaps the most unstable of the three most commonly used biotherapeutics, the others being DNA and protein, the advantages that using RNA presents are now being realized at a high rate. The development of methods to protect it from degradation and deliver it in vivo has fueled more research into uses that were once considered heretical. In this age of enlightenment we are seeing significant investments in the 'RNA approach' both in academia and industry. Thus, along with developing RNA encoding antigens for vaccine development for cancer and infectious diseases, RNA is now used to program cells in vivo or ex vivo. In the following review we have chosen to highlight a few of the most recent studies that use RNA as a means to alter a disease state. These papers were chosen to indicate the breadth of research that is ongoing and hopefully to inspire others to consider new ways to treat cancer, infectious disease, or genetic disorders with RNA-based approaches.

Authors
Boczkowski, D; Nair, SK
MLA Citation
Boczkowski, D, and Nair, SK. "The RNAissance period." Discovery medicine 22.119 (August 2016): 67-72.
PMID
27585232
Source
epmc
Published In
Discovery medicine
Volume
22
Issue
119
Publish Date
2016
Start Page
67
End Page
72

From the RNA world to the clinic.

The study of RNA has continually emphasized the structural and functional versatility of RNA molecules. This versatility has inspired translational and clinical researchers to explore the utility of RNA-based therapeutic agents for a wide variety of medical applications. Several RNA therapeutics, with diverse modes of action, are being evaluated in large late-stage clinical trials, and many more are in early clinical development. Hundreds of patients are enrolled in large trials testing messenger RNAs to combat cancer, small interfering RNAs to treat renal and hepatic disorders, and aptamers to combat ocular and cardiovascular disease. Results from these studies are generating considerable interest among the biomedical community and the public and will be important for the future development of this emerging class of therapeutic agents.

Authors
Sullenger, BA; Nair, S
MLA Citation
Sullenger, BA, and Nair, S. "From the RNA world to the clinic." Science (New York, N.Y.) 352.6292 (June 2016): 1417-1420.
PMID
27313039
Source
epmc
Published In
Science
Volume
352
Issue
6292
Publish Date
2016
Start Page
1417
End Page
1420
DOI
10.1126/science.aad8709

RNA Vaccination Therapy: Advances in an Emerging Field.

Authors
Kreiter, S; Diken, M; Pascolo, S; Nair, SK; Thielemans, KM; Geall, A
MLA Citation
Kreiter, S, Diken, M, Pascolo, S, Nair, SK, Thielemans, KM, and Geall, A. "RNA Vaccination Therapy: Advances in an Emerging Field." Journal of immunology research 2016 (January 2016): 9703914-.
PMID
27019856
Source
epmc
Published In
Journal of Immunology Research
Volume
2016
Publish Date
2016
Start Page
9703914
DOI
10.1155/2016/9703914

Transfecting Human Monocytes with RNA.

Targeting monocytes as a delivery system for drugs or nucleic acids, and thereby harnessing their natural tissue-infiltrating capacity, has become an area of intense investigation in both basic and clinical research. Herein we describe an efficient method to deliver mRNA (messenger RNA) or siRNA (small interfering RNA) into human monocytes by electroporation. This method can be applied in the laboratory to monocytes isolated via magnetic bead-based techniques, or in a clinical setting using monocytes that were collected via counterflow centrifugation elutriation using the Elutra(®) Cell Separation System. We further demonstrate that electroporation of monocytes with RNA represents a robust and highly relevant approach to modify monocytes for cell-based therapies. Last, the procedure described can readily be adapted to monocytes from different species, hence facilitating research in animal models.

Authors
Dannull, J; Nair, SK
MLA Citation
Dannull, J, and Nair, SK. "Transfecting Human Monocytes with RNA." Methods in molecular biology (Clifton, N.J.) 1428 (January 2016): 177-186.
PMID
27236800
Source
epmc
Published In
Methods in molecular biology (Clifton, N.J.)
Volume
1428
Publish Date
2016
Start Page
177
End Page
186
DOI
10.1007/978-1-4939-3625-0_12

Abstract A157: Oncolytic poliovirus mediated immune events

Authors
Brown, MC; Holl, EK; Boczkowski, D; Bigner, DD; Gromeier, M; Nair, SK
MLA Citation
Brown, MC, Holl, EK, Boczkowski, D, Bigner, DD, Gromeier, M, and Nair, SK. "Abstract A157: Oncolytic poliovirus mediated immune events." Cancer Immunology Research 4.1 Supplement (January 2016): A157-A157.
Source
crossref
Published In
Cancer Immunology Research
Volume
4
Issue
1 Supplement
Publish Date
2016
Start Page
A157
End Page
A157
DOI
10.1158/2326-6074.CRICIMTEATIAACR15-A157

RNA-Mediated Reprogramming of Primary Adult Human Dermal Fibroblasts into c-kit(+) Cardiac Progenitor Cells.

Cardiovascular disease is the leading cause of death in the United States. Heart failure is a common, costly, and potentially fatal condition that is inadequately managed by pharmaceuticals. Cardiac repair therapies are promising alternative options. A potential cardiac repair therapy involves reprogramming human fibroblasts toward an induced cardiac progenitor-like state. We developed a clinically useful and safer reprogramming method by nonintegrative delivery of a cocktail of cardiac transcription factor-encoding mRNAs into autologous human dermal fibroblasts obtained from skin biopsies. Using this method, adult and neonatal dermal fibroblasts were reprogrammed into cardiac progenitor cells (CPCs) that expressed c-kit, Isl-1, and Nkx2.5. Furthermore, these reprogrammed CPCs differentiated into cardiomyocytes (CMs) in vitro as judged by increased expression of cardiac troponin T, α-sarcomeric actinin, RyR2, and SERCA2 and displayed enhanced caffeine-sensitive calcium release. The ability to reprogram patient-derived dermal fibroblasts into c-kit(+) CPCs and differentiate them into functional CMs provides clinicians with a potential new source of CPCs for cardiac repair from a renewable source and an alternative therapy in the treatment of heart failure.

Authors
Pratico, ED; Feger, BJ; Watson, MJ; Sullenger, BA; Bowles, DE; Milano, CA; Nair, SK
MLA Citation
Pratico, ED, Feger, BJ, Watson, MJ, Sullenger, BA, Bowles, DE, Milano, CA, and Nair, SK. "RNA-Mediated Reprogramming of Primary Adult Human Dermal Fibroblasts into c-kit(+) Cardiac Progenitor Cells." Stem cells and development 24.22 (November 2015): 2622-2633.
PMID
26176491
Source
epmc
Published In
Stem Cells and Development
Volume
24
Issue
22
Publish Date
2015
Start Page
2622
End Page
2633
DOI
10.1089/scd.2015.0073

Ex vivo generation of dendritic cells from cryopreserved, post-induction chemotherapy, mobilized leukapheresis from pediatric patients with medulloblastoma.

Generation of patient-derived, autologous dendritic cells (DCs) is a critical component of cancer immunotherapy with ex vivo-generated, tumor antigen-loaded DCs. An important factor in the ability to generate DCs is the potential impact of prior therapies on DC phenotype and function. We investigated the ability to generate DCs using cells harvested from pediatric patients with medulloblastoma for potential evaluation of DC-RNA based vaccination approach in this patient population. Cells harvested from medulloblastoma patient leukapheresis following induction chemotherapy and granulocyte colony stimulating factor mobilization were cryopreserved prior to use in DC generation. DCs were generated from the adherent CD14+ monocytes using standard procedures and analyzed for cell recovery, phenotype and function. To summarize, 4 out of 5 patients (80%) had sufficient monocyte recovery to permit DC generation, and we were able to generate DCs from 3 out of these 4 patient samples (75%). Overall, we successfully generated DCs that met phenotypic requisites for DC-based cancer therapy from 3 out of 5 (60%) patient samples and met both phenotypic and functional requisites from 2 out of 5 (40%) patient samples. This study highlights the potential to generate functional DCs for further clinical treatments from refractory patients that have been heavily pretreated with myelosuppressive chemotherapy. Here we demonstrate the utility of evaluating the effect of the currently employed standard-of-care therapies on the ex vivo generation of DCs for DC-based clinical studies in cancer patients.

Authors
Nair, SK; Driscoll, T; Boczkowski, D; Schmittling, R; Reynolds, R; Johnson, LA; Grant, G; Fuchs, H; Bigner, DD; Sampson, JH; Gururangan, S; Mitchell, DA
MLA Citation
Nair, SK, Driscoll, T, Boczkowski, D, Schmittling, R, Reynolds, R, Johnson, LA, Grant, G, Fuchs, H, Bigner, DD, Sampson, JH, Gururangan, S, and Mitchell, DA. "Ex vivo generation of dendritic cells from cryopreserved, post-induction chemotherapy, mobilized leukapheresis from pediatric patients with medulloblastoma." Journal of neuro-oncology 125.1 (October 2015): 65-74.
PMID
26311248
Source
epmc
Published In
Journal of Neuro-Oncology
Volume
125
Issue
1
Publish Date
2015
Start Page
65
End Page
74
DOI
10.1007/s11060-015-1890-2

Intranasal mRNA nanoparticle vaccination induces prophylactic and therapeutic anti-tumor immunity.

Authors
Phua, KKL; Staats, HF; Nair, SK; Leong, KW
MLA Citation
Phua, KKL, Staats, HF, Nair, SK, and Leong, KW. "Intranasal mRNA nanoparticle vaccination induces prophylactic and therapeutic anti-tumor immunity." Journal of controlled release : official journal of the Controlled Release Society 213 (September 2015): e66-e67.
PMID
27005208
Source
epmc
Published In
Journal of Controlled Release
Volume
213
Publish Date
2015
Start Page
e66
End Page
e67
DOI
10.1016/j.jconrel.2015.05.110

Identification and Characterization of a B Cell Aptamer That Targets Diffuse Large B Cell Lymphoma (DLBCL) and Chronic Myelogenous Leukemia (CML)

Authors
Pratico, ED; Nair, SK; Sullenger, BA
MLA Citation
Pratico, ED, Nair, SK, and Sullenger, BA. "Identification and Characterization of a B Cell Aptamer That Targets Diffuse Large B Cell Lymphoma (DLBCL) and Chronic Myelogenous Leukemia (CML)." May 2015.
Source
wos-lite
Published In
Molecular Therapy
Volume
23
Publish Date
2015
Start Page
S29
End Page
S29

Tetanus toxoid and CCL3 improve dendritic cell vaccines in mice and glioblastoma patients.

After stimulation, dendritic cells (DCs) mature and migrate to draining lymph nodes to induce immune responses. As such, autologous DCs generated ex vivo have been pulsed with tumour antigens and injected back into patients as immunotherapy. While DC vaccines have shown limited promise in the treatment of patients with advanced cancers including glioblastoma, the factors dictating DC vaccine efficacy remain poorly understood. Here we show that pre-conditioning the vaccine site with a potent recall antigen such as tetanus/diphtheria (Td) toxoid can significantly improve the lymph node homing and efficacy of tumour-antigen-specific DCs. To assess the effect of vaccine site pre-conditioning in humans, we randomized patients with glioblastoma to pre-conditioning with either mature DCs or Td unilaterally before bilateral vaccination with DCs pulsed with Cytomegalovirus phosphoprotein 65 (pp65) RNA. We and other laboratories have shown that pp65 is expressed in more than 90% of glioblastoma specimens but not in surrounding normal brain, providing an unparalleled opportunity to subvert this viral protein as a tumour-specific target. Patients given Td had enhanced DC migration bilaterally and significantly improved survival. In mice, Td pre-conditioning also enhanced bilateral DC migration and suppressed tumour growth in a manner dependent on the chemokine CCL3. Our clinical studies and corroborating investigations in mice suggest that pre-conditioning with a potent recall antigen may represent a viable strategy to improve anti-tumour immunotherapy.

Authors
Mitchell, DA; Batich, KA; Gunn, MD; Huang, M-N; Sanchez-Perez, L; Nair, SK; Congdon, KL; Reap, EA; Archer, GE; Desjardins, A; Friedman, AH; Friedman, HS; Herndon, JE; Coan, A; McLendon, RE; Reardon, DA; Vredenburgh, JJ; Bigner, DD; Sampson, JH
MLA Citation
Mitchell, DA, Batich, KA, Gunn, MD, Huang, M-N, Sanchez-Perez, L, Nair, SK, Congdon, KL, Reap, EA, Archer, GE, Desjardins, A, Friedman, AH, Friedman, HS, Herndon, JE, Coan, A, McLendon, RE, Reardon, DA, Vredenburgh, JJ, Bigner, DD, and Sampson, JH. "Tetanus toxoid and CCL3 improve dendritic cell vaccines in mice and glioblastoma patients." Nature 519.7543 (March 11, 2015): 366-369.
PMID
25762141
Source
epmc
Published In
Nature
Volume
519
Issue
7543
Publish Date
2015
Start Page
366
End Page
369
DOI
10.1038/nature14320

Gene Expression Profile of Dendritic Cell-Tumor Cell Hybrids Determined by Microarrays and Its Implications for Cancer Immunotherapy.

Dendritic cell- (DC-) tumor fusion cells stimulate effective in vivo antitumor responses. However, therapeutic approaches are dependent upon the coadministration of exogenous 3rd signals. The purpose of this study was to determine the mechanisms for inadequate 3rd signaling by electrofused DC-tumor cell hybrids.Murine melanoma cells were fused with DCs derived from C57BL/6 mice. Quantitative real-time PCR (qPCR) was used to determine relative changes in Th (T helper) 1 and Th2 cytokine gene expression. In addition, changes in gene expression of fusion cells were determined by microarray. Last, cytokine secretion by fusion cells upon inhibition of signaling pathways was analyzed by ELISA.qPCR analyses revealed that fusion cells exhibited a downregulation of Th1 associated cytokines IL-12 and IL-15 and an upregulation of the Th2 cytokine IL-4. Microarray studies further showed that the expression of chemokines, costimulatory molecules, and matrix-metalloproteinases was deregulated in fusion cells. Lastly, inhibitor studies demonstrate that inhibition of the PI3K/Akt/mTOR signaling pathway could restore the secretion of bioactive IL-12p70 by fusion cells.Our results suggest that combining fusion cell-based vaccination with administration of inhibitors of the PI3K/Akt/mTOR signaling pathway may enhance antitumor responses in patients.

Authors
Dannull, J; Tan, C; Farrell, C; Wang, C; Pruitt, S; Nair, SK; Lee, WT
MLA Citation
Dannull, J, Tan, C, Farrell, C, Wang, C, Pruitt, S, Nair, SK, and Lee, WT. "Gene Expression Profile of Dendritic Cell-Tumor Cell Hybrids Determined by Microarrays and Its Implications for Cancer Immunotherapy." Journal of immunology research 2015 (January 2015): 789136-.
PMID
26605345
Source
epmc
Published In
Journal of Immunology Research
Volume
2015
Publish Date
2015
Start Page
789136
DOI
10.1155/2015/789136

RNA-Based Vaccines in Cancer Immunotherapy.

RNA vaccines traditionally consist of messenger RNA synthesized by in vitro transcription using a bacteriophage RNA polymerase and template DNA that encodes the antigen(s) of interest. Once administered and internalized by host cells, the mRNA transcripts are translated directly in the cytoplasm and then the resulting antigens are presented to antigen presenting cells to stimulate an immune response. Alternatively, dendritic cells can be loaded with either tumor associated antigen mRNA or total tumor RNA and delivered to the host to elicit a specific immune response. In this review, we will explain why RNA vaccines represent an attractive platform for cancer immunotherapy, discuss modifications to RNA structure that have been developed to optimize mRNA vaccine stability and translational efficiency, and describe strategies for nonviral delivery of mRNA vaccines, highlighting key preclinical and clinical data related to cancer immunotherapy.

Authors
McNamara, MA; Nair, SK; Holl, EK
MLA Citation
McNamara, MA, Nair, SK, and Holl, EK. "RNA-Based Vaccines in Cancer Immunotherapy." Journal of immunology research 2015 (January 2015): 794528-. (Review)
PMID
26665011
Source
epmc
Published In
Journal of Immunology Research
Volume
2015
Publish Date
2015
Start Page
794528
DOI
10.1155/2015/794528

Oncolytic polio virotherapy of cancer.

Recently, the century-old idea of targeting cancer with viruses (oncolytic viruses) has come of age, and promise has been documented in early stage and several late-stage clinical trials in a variety of cancers. Although originally prized for their direct tumor cytotoxicity (oncolytic virotherapy), recently, the proinflammatory and immunogenic effects of viral tumor infection (oncolytic immunotherapy) have come into focus. Indeed, a capacity for eliciting broad, sustained antineoplastic effects stemming from combined direct viral cytotoxicity, innate antiviral activation, stromal proinflammatory stimulation, and recruitment of adaptive immune effector responses is the greatest asset of oncolytic viruses. However, it also is the source for enormous mechanistic complexity that must be considered for successful clinical translation. Because of fundamentally different relationships with their hosts (malignant or not), diverse replication strategies, and distinct modes of tumor cytotoxicity/killing, oncolytic viruses should not be referred to collectively. These agents must be evaluated based on their individual merits. In this review, the authors highlight key mechanistic principles of cancer treatment with the polio:rhinovirus chimera PVSRIPO and their implications for oncolytic immunotherapy in the clinic.

Authors
Brown, MC; Dobrikova, EY; Dobrikov, MI; Walton, RW; Gemberling, SL; Nair, SK; Desjardins, A; Sampson, JH; Friedman, HS; Friedman, AH; Tyler, DS; Bigner, DD; Gromeier, M
MLA Citation
Brown, MC, Dobrikova, EY, Dobrikov, MI, Walton, RW, Gemberling, SL, Nair, SK, Desjardins, A, Sampson, JH, Friedman, HS, Friedman, AH, Tyler, DS, Bigner, DD, and Gromeier, M. "Oncolytic polio virotherapy of cancer." Cancer 120.21 (November 2014): 3277-3286. (Review)
PMID
24939611
Source
epmc
Published In
Cancer
Volume
120
Issue
21
Publish Date
2014
Start Page
3277
End Page
3286
DOI
10.1002/cncr.28862

Messenger RNA (mRNA) nanoparticle tumour vaccination.

Use of mRNA-based vaccines for tumour immunotherapy has gained increasing attention in recent years. A growing number of studies applying nanomedicine concepts to mRNA tumour vaccination show that the mRNA delivered in nanoparticle format can generate a more robust immune response. Advances in the past decade have deepened our understanding of gene delivery barriers, mRNA's biological stability and immunological properties, and support the notion for engineering innovations tailored towards a more efficient mRNA nanoparticle vaccine delivery system. In this review we will first examine the suitability of mRNA for engineering manipulations, followed by discussion of a model framework that highlights the barriers to a robust anti-tumour immunity mediated by mRNA encapsulated in nanoparticles. Finally, by consolidating existing literature on mRNA nanoparticle tumour vaccination within the context of this framework, we aim to identify bottlenecks that can be addressed by future nanoengineering research.

Authors
Phua, KKL; Nair, SK; Leong, KW
MLA Citation
Phua, KKL, Nair, SK, and Leong, KW. "Messenger RNA (mRNA) nanoparticle tumour vaccination." Nanoscale 6.14 (July 2014): 7715-7729. (Review)
PMID
24904987
Source
epmc
Published In
Nanoscale
Volume
6
Issue
14
Publish Date
2014
Start Page
7715
End Page
7729
DOI
10.1039/c4nr01346h

RANDOMIZATION OF PATIENTS WITH GLIOBLASTOMA TO VACCINE SITE PRE-CONDITIONING WITH TETANUS-DIPHTHERIA TOXOID SYSTEMICALLY ENHANCES MIGRATION AND THERAPEUTIC EFFECT OF CYTOMEGALOVIRUS PP65-PULSED DENDRITIC CELL VACCINE IN A MIP-1α-DEPENDENT FASHION.

Dendritic cell (DC) vaccine efficacy is limited by suboptimal migration to vaccine site-draining lymph nodes (VDLNs). In mice, vaccine site conditioning with inflammatory cytokines or mature DCs increases DC trafficking and the induction of antigen-specific T cells. We assessed the impact of DC migration to VDLNs on clinical outcomes in patients with newly-diagnosed glioblastoma (GBM) by randomizing patients to one of two vaccine site conditioning strategies.

Authors
Sampson, J; Mitchell, DA; Batich, KA; Snyder, D; Xie, W; Reap, E; Cui, X; Sanchez-Perez, L; Archer, GE; Nair, SK; Gunn, MD
MLA Citation
Sampson, J, Mitchell, DA, Batich, KA, Snyder, D, Xie, W, Reap, E, Cui, X, Sanchez-Perez, L, Archer, GE, Nair, SK, and Gunn, MD. "RANDOMIZATION OF PATIENTS WITH GLIOBLASTOMA TO VACCINE SITE PRE-CONDITIONING WITH TETANUS-DIPHTHERIA TOXOID SYSTEMICALLY ENHANCES MIGRATION AND THERAPEUTIC EFFECT OF CYTOMEGALOVIRUS PP65-PULSED DENDRITIC CELL VACCINE IN A MIP-1α-DEPENDENT FASHION." England. July 2014.
PMID
25165316
Source
pubmed
Published In
Neuro-Oncology
Volume
16 Suppl 3
Publish Date
2014
Start Page
iii39
End Page
iii40
DOI
10.1093/neuonc/nou208.63

Intranasal mRNA nanoparticle vaccination induces prophylactic and therapeutic anti-tumor immunity.

Direct in vivo administration of messenger RNA (mRNA) delivered in both naked and nanoparticle formats are actively investigated because the use of dendritic cells transfected ex vivo with mRNA for cancer therapy is expensive and needs significant infrastructure. Notably, intravenous and subcutaneous injections are the only routes of administration tested for mRNA nanoparticle tumor vaccination. In this report, we demonstrate that tumor immunity can be achieved via nasal administration of mRNA. Mice nasally immunized with mRNA delivered in nanoparticle format demonstrate delayed tumor progression in both prophylactic and therapeutic immunization models. The observed tumor immunity correlates with splenic antigen-specific CD8+ T cells and is achieved only when mRNA is delivered in nanoparticle but not in naked format. In conclusion, we demonstrate, as a proof-of-concept, a non-invasive approach to mRNA tumor vaccination, increasing its potential as a broadly applicable and off-the-shelf therapy for cancer treatment.

Authors
Phua, KKL; Staats, HF; Leong, KW; Nair, SK
MLA Citation
Phua, KKL, Staats, HF, Leong, KW, and Nair, SK. "Intranasal mRNA nanoparticle vaccination induces prophylactic and therapeutic anti-tumor immunity." Scientific reports 4 (June 4, 2014): 5128-.
PMID
24894817
Source
epmc
Published In
Scientific Reports
Volume
4
Publish Date
2014
Start Page
5128
DOI
10.1038/srep05128

Whole blood cells loaded with messenger RNA as an anti-tumor vaccine.

The use of a cell-based vaccine composed of autologous whole blood cells loaded with mRNA is described. Mice immunized with whole blood cells loaded with mRNA encoding antigen develop anti-tumor immunity comparable to DC-RNA immunization. This approach offers a simple and affordable alternative to RNA-based cellular therapy by circumventing complex, laborious and expensive ex vivo manipulations required for DC-based immunizations.

Authors
Phua, KKL; Boczkowski, D; Dannull, J; Pruitt, S; Leong, KW; Nair, SK
MLA Citation
Phua, KKL, Boczkowski, D, Dannull, J, Pruitt, S, Leong, KW, and Nair, SK. "Whole blood cells loaded with messenger RNA as an anti-tumor vaccine." Advanced healthcare materials 3.6 (June 2014): 837-842.
PMID
24339387
Source
epmc
Published In
Advanced healthcare materials
Volume
3
Issue
6
Publish Date
2014
Start Page
837
End Page
842
DOI
10.1002/adhm.201300512

Recognition and killing of autologous, primary glioblastoma tumor cells by human cytomegalovirus pp65-specific cytotoxic T cells.

Despite aggressive conventional therapy, glioblastoma (GBM) remains uniformly lethal. Immunotherapy, in which the immune system is harnessed to specifically attack malignant cells, offers a treatment option with less toxicity. The expression of cytomegalovirus (CMV) antigens in GBM presents a unique opportunity to target these viral proteins for tumor immunotherapy. Although the presence of CMV within malignant gliomas has been confirmed by several laboratories, its relevance as an immunologic target in GBM has yet to be established. The objective of this study was to explore whether T cells stimulated by CMV pp65 RNA-transfected dendritic cells (DC) target and eliminate autologous GBM tumor cells in an antigen-specific manner.T cells from patients with GBM were stimulated with autologous DCs pulsed with CMV pp65 RNA, and the function of the effector CMV pp65-specific T cells was measured.In this study, we demonstrate the ability to elicit CMV pp65-specific immune responses in vitro using RNA-pulsed autologous DCs generated from patients with newly diagnosed GBM. Importantly, CMV pp65-specific T cells lyse autologous, primary GBM tumor cells in an antigen-specific manner. Moreover, T cells expanded in vitro using DCs pulsed with total tumor RNA demonstrated a 10- to 20-fold expansion of CMV pp65-specific T cells as assessed by tetramer analysis and recognition and killing of CMV pp65-expressing target cells.These data collectively demonstrate that CMV-specific T cells can effectively target glioblastoma tumor cells for immunologic killing and support the rationale for the development of CMV-directed immunotherapy in patients with GBM.

Authors
Nair, SK; De Leon, G; Boczkowski, D; Schmittling, R; Xie, W; Staats, J; Liu, R; Johnson, LA; Weinhold, K; Archer, GE; Sampson, JH; Mitchell, DA
MLA Citation
Nair, SK, De Leon, G, Boczkowski, D, Schmittling, R, Xie, W, Staats, J, Liu, R, Johnson, LA, Weinhold, K, Archer, GE, Sampson, JH, and Mitchell, DA. "Recognition and killing of autologous, primary glioblastoma tumor cells by human cytomegalovirus pp65-specific cytotoxic T cells." Clinical cancer research : an official journal of the American Association for Cancer Research 20.10 (May 2014): 2684-2694.
PMID
24658154
Source
epmc
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
20
Issue
10
Publish Date
2014
Start Page
2684
End Page
2694
DOI
10.1158/1078-0432.ccr-13-3268

High-throughput identification and dendritic cell-based functional validation of MHC class I-restricted Mycobacterium tuberculosis epitopes.

Emergence of drug-resistant strains of the pathogen Mycobacterium tuberculosis (Mtb) and the ineffectiveness of BCG in curtailing Mtb infection makes vaccine development for tuberculosis an important objective. Identifying immunogenic CD8+ T cell peptide epitopes is necessary for peptide-based vaccine strategies. We present a three-tiered strategy for identifying and validating immunogenic peptides: first, identify peptides that form stable complexes with class I MHC molecules; second, determine whether cytotoxic T lymphocytes (CTLs) raised against the whole protein antigen recognize and lyse target cells pulsed with peptides that passed step 1; third, determine whether peptides that passed step 2, when administered in vivo as a vaccine in HLA-A2 transgenic mice, elicit CTLs that lyse target cells expressing the whole protein antigen. Our innovative approach uses dendritic cells transfected with Mtb antigen-encoding mRNA to drive antigen expression. Using this strategy, we have identified five novel peptide epitopes from the Mtb proteins Apa, Mtb8.4 and Mtb19.

Authors
Nair, SK; Tomaras, GD; Sales, AP; Boczkowski, D; Chan, C; Plonk, K; Cai, Y; Dannull, J; Kepler, TB; Pruitt, SK; Weinhold, KJ
MLA Citation
Nair, SK, Tomaras, GD, Sales, AP, Boczkowski, D, Chan, C, Plonk, K, Cai, Y, Dannull, J, Kepler, TB, Pruitt, SK, and Weinhold, KJ. "High-throughput identification and dendritic cell-based functional validation of MHC class I-restricted Mycobacterium tuberculosis epitopes." Scientific reports 4 (April 23, 2014): 4632-.
PMID
24755960
Source
epmc
Published In
Scientific Reports
Volume
4
Publish Date
2014
Start Page
4632
DOI
10.1038/srep04632

EGFRvIII mCAR-modified T-cell therapy cures mice with established intracerebral glioma and generates host immunity against tumor-antigen loss.

PURPOSE: Chimeric antigen receptor (CAR) transduced T cells represent a promising immune therapy that has been shown to successfully treat cancers in mice and humans. However, CARs targeting antigens expressed in both tumors and normal tissues have led to significant toxicity. Preclinical studies have been limited by the use of xenograft models that do not adequately recapitulate the immune system of a clinically relevant host. A constitutively activated mutant of the naturally occurring epidermal growth factor receptor (EGFRvIII) is antigenically identical in both human and mouse glioma, but is also completely absent from any normal tissues. EXPERIMENTAL DESIGN: We developed a third-generation, EGFRvIII-specific murine CAR (mCAR), and performed tests to determine its efficacy in a fully immunocompetent mouse model of malignant glioma. RESULTS: At elevated doses, infusion with EGFRvIII mCAR T cells led to cures in all mice with brain tumors. In addition, antitumor efficacy was found to be dependent on lymphodepletive host conditioning. Selective blockade with EGFRvIII soluble peptide significantly abrogated the activity of EGFRvIII mCAR T cells in vitro and in vivo, and may offer a novel strategy to enhance the safety profile for CAR-based therapy. Finally, mCAR-treated, cured mice were resistant to rechallenge with EGFRvIII(NEG) tumors, suggesting generation of host immunity against additional tumor antigens. CONCLUSION: All together, these data support that third-generation, EGFRvIII-specific mCARs are effective against gliomas in the brain and highlight the importance of syngeneic, immunocompetent models in the preclinical evaluation of tumor immunotherapies.

Authors
Sampson, JH; Choi, BD; Sanchez-Perez, L; Suryadevara, CM; Snyder, DJ; Flores, CT; Schmittling, RJ; Nair, SK; Reap, EA; Norberg, PK; Herndon, JE; Kuan, C-T; Morgan, RA; Rosenberg, SA; Johnson, LA
MLA Citation
Sampson, JH, Choi, BD, Sanchez-Perez, L, Suryadevara, CM, Snyder, DJ, Flores, CT, Schmittling, RJ, Nair, SK, Reap, EA, Norberg, PK, Herndon, JE, Kuan, C-T, Morgan, RA, Rosenberg, SA, and Johnson, LA. "EGFRvIII mCAR-modified T-cell therapy cures mice with established intracerebral glioma and generates host immunity against tumor-antigen loss." Clin Cancer Res 20.4 (February 15, 2014): 972-984.
PMID
24352643
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
20
Issue
4
Publish Date
2014
Start Page
972
End Page
984
DOI
10.1158/1078-0432.CCR-13-0709

Immunological targeting of cytomegalovirus for glioblastoma therapy.

Human cytomegalovirus (CMV) is purportedly present in glioblastoma (GBM) while absent from the normal brain, making CMV antigens potentially ideal immunological anti-GBM targets. We recently demonstrated that patient-derived CMV pp65-specific T cells are capable of recognizing and killing autologous GBM tumor cells. This data supports CMV antigen-directed immunotherapies against GBM.

Authors
Nair, SK; Sampson, JH; Mitchell, DA
MLA Citation
Nair, SK, Sampson, JH, and Mitchell, DA. "Immunological targeting of cytomegalovirus for glioblastoma therapy." Oncoimmunology 3 (January 2014): e29289-.
PMID
25101224
Source
epmc
Published In
OncoImmunology
Volume
3
Publish Date
2014
Start Page
e29289
DOI
10.4161/onci.29289

Local secretion of IL-12 augments the therapeutic impact of dendritic cell-tumor cell fusion vaccination.

BACKGROUND: The development of dendritic cell (DC)-tumor fusion vaccines is a promising approach in cancer immunotherapy. Using fusion vaccines allows a broad spectrum of known and unidentified tumor-associated antigens to be presented in the context of MHC class I and class II molecules, with potent co-stimulation provided by the DCs. Although DC-tumor fusion cells are immunogenic, murine studies have shown that effective immunotherapy requires a third signal, which can be provided by exogenous interleukin 12 (IL-12). Unfortunately, systemic administration of IL-12 induces severe toxicity in cancer patients, potentially precluding clinical use of this cytokine to augment fusion vaccine efficacy. To overcome this limitation, we developed a novel approach in which DC-tumor fusion cells locally secrete IL-12, then evaluated the effectiveness of this approach in a murine B16 melanoma model. MATERIALS AND METHODS: Tumor cells were stably transduced to secrete murine IL-12p70. These tumor cells were then electrofused to DC to form DC-tumor heterokaryons. These cells were used to treat established B16 pulmonary metastases. Enumeration of these metastases was performed and compared between experimental groups using Wilcoxon rank sum test. Interferon γ enzyme-linked immunosorbent spot assay was performed on splenocytes from treated mice. RESULTS: We show that vaccination with DCs fused to syngeneic melanoma cells that stably express murine IL-12p70 significantly reduces counts of established lung metastases in treated animals when compared with DC-tumor alone (P = 0.029). Interferon γ enzyme-linked immunosorbent spot assays suggest that this antitumor response is mediated by CD4(+) T cells, in the absence of a tumor-specific CD8(+) T cell response, and that the concomitant induction of antitumor CD4(+) and CD8(+) T cell responses required exogenous IL-12. CONCLUSIONS: This study is, to the best of our knowledge, the first report that investigates the impact of local secretion of IL-12 on antitumor immunity induced by a DC-tumor fusion cell vaccine in a melanoma model and may aid the rational design of future clinical trials.

Authors
Tan, C; Dannull, J; Nair, SK; Ding, E; Tyler, DS; Pruitt, SK; Lee, WT
MLA Citation
Tan, C, Dannull, J, Nair, SK, Ding, E, Tyler, DS, Pruitt, SK, and Lee, WT. "Local secretion of IL-12 augments the therapeutic impact of dendritic cell-tumor cell fusion vaccination." J Surg Res 185.2 (December 2013): 904-911.
PMID
23891424
Source
pubmed
Published In
Journal of Surgical Research
Volume
185
Issue
2
Publish Date
2013
Start Page
904
End Page
911
DOI
10.1016/j.jss.2013.06.045

Impact of anti-CD25 monoclonal antibody on dendritic cell-tumor fusion vaccine efficacy in a murine melanoma model.

BACKGROUND: A promising cancer vaccine involves the fusion of tumor cells with dendritic cells (DCs). As such, a broad spectrum of both known and unidentified tumor antigens is presented to the immune system in the context of the potent immunostimulatory capacity of DCs. Murine studies have demonstrated the efficacy of fusion immunotherapy. However the clinical impact of DC/tumor fusion vaccines has been limited, suggesting that the immunosuppresive milieu found in patients with malignancies may blunt the efficacy of cancer vaccination. Thus, novel strategies to enhance fusion vaccine efficacy are needed. Regulatory T cells (Tregs) are known to suppress anti-tumor immunity, and depletion or functional inactivation of these cells improves immunotherapy in both animal models and clinical trials. In this study, we sought to investigate whether functional inactivation of CD4+CD25+FoxP3+ Treg with anti-CD25 monoclonal antibody (mAb) PC61 prior to DC/tumor vaccination would significantly improve immunotherapy in the murine B16 melanoma model. METHODS: Treg blockade was achieved with systemic PC61 administration. This blockage was done in conjunction with DC/tumor fusion vaccine administration to treat established melanoma pulmonary metastases. Enumeration of these metastases was performed and compared between experimental groups using Wilcoxon Rank Sum Test. IFN-gamma ELISPOT assay was performed on splenocytes from treated mice. RESULTS: We demonstrate that treatment of mice with established disease using mAb PC61 and DC/tumor fusion significantly reduced counts of pulmonary metastases compared to treatment with PC61 alone (p=0.002) or treatment with control antibody plus fusion vaccine (p=0.0397). Furthermore, IFN-gamma ELISPOT analyses reveal that the increase in cancer immunity was mediated by anti-tumor specific CD4+ T-helper cells, without concomitant induction of CD8+ cytotoxic T cells. Lastly, our data provide proof of principle that combination treatment with mAb PC61 and systemic IL-12 can lower the dose of IL-12 necessary to obtain maximal therapeutic efficacy. CONCLUSIONS: To our knowledge, this is the first report investigating the effects of anti-CD25 mAb administration on DC/tumor-fusion vaccine efficacy in a murine melanoma model, and our results may aide the design of future clinical trials with enhanced therapeutic impact.

Authors
Tan, C; Reddy, V; Dannull, J; Ding, E; Nair, SK; Tyler, DS; Pruitt, SK; Lee, WT
MLA Citation
Tan, C, Reddy, V, Dannull, J, Ding, E, Nair, SK, Tyler, DS, Pruitt, SK, and Lee, WT. "Impact of anti-CD25 monoclonal antibody on dendritic cell-tumor fusion vaccine efficacy in a murine melanoma model. (Published online)" J Transl Med 11 (June 17, 2013): 148-.
PMID
23768240
Source
pubmed
Published In
Journal of Translational Medicine
Volume
11
Publish Date
2013
Start Page
148
DOI
10.1186/1479-5876-11-148

Transfection efficiency and transgene expression kinetics of mRNA delivered in naked and nanoparticle format.

Transfection efficiencies and transgene expression kinetics of messenger RNA (mRNA), an emerging class of nucleic acid-based therapeutics, have been poorly characterized. In this study, we evaluated transfection efficiencies of mRNA delivered in naked and nanoparticle format in vitro and in vivo using GFP and luciferase as reporters. While mRNA nanoparticles transfect primary human and mouse dendritic cells (DCs) efficiently in vitro, naked mRNA could not produce any detectable gene product. The protein expression of nanoparticle-mediated transfection in vitro peaks rapidly within 5-7h and decays in a biphasic manner. In vivo, naked mRNA is more efficient than mRNA nanoparticles when administered subcutaneously. In contrast, mRNA nanoparticle performs better when administered intranasally and intravenously. Gene expression is most transient when delivered intravenously in nanoparticle format with an apparent half-life of 1.4h and lasts less than 24h, and most sustained when delivered in the naked format subcutaneously at the base of tail with an apparent half-life of 18h and persists for at least 6days. Notably, exponential decreases in protein expression are consistently observed post-delivery of mRNA in vivo regardless of the mode of delivery (naked or nanoparticle) or the site of administration. This study elucidates the performance of mRNA transfection and suggests a niche for mRNA therapeutics when predictable in vivo transgene expression kinetics is imperative.

Authors
Phua, KKL; Leong, KW; Nair, SK
MLA Citation
Phua, KKL, Leong, KW, and Nair, SK. "Transfection efficiency and transgene expression kinetics of mRNA delivered in naked and nanoparticle format." J Control Release 166.3 (March 28, 2013): 227-233.
PMID
23306021
Source
pubmed
Published In
Journal of Controlled Release
Volume
166
Issue
3
Publish Date
2013
Start Page
227
End Page
233
DOI
10.1016/j.jconrel.2012.12.029

Identification and characterization of an agonistic aptamer against the T cell costimulatory receptor, OX40.

Induction of an effective immune response that can target and eliminate malignant cells or virus-infected cells requires the stimulation of antigen-specific effector T cells. A productive and long-lasting memory response requires 2 signals: a specific signal provided by antigen recognition through engagement of the T cell receptor and a secondary signal via engagement of costimulatory molecules (such as OX40) on these newly activated T cells. The OX40-OX40-ligand interaction is critical for the generation of productive effector and memory T cell functions. Thus agonistic antibodies that stimulate OX40 on activated T cells have been used as adjuvants to augment immune responses. We previously demonstrated that an aptamer modified to stimulate murine OX40 enhanced vaccine-mediated immune responses in a murine melanoma model. In this study, we describe the development of an agonistic aptamer that targets human OX40 (hOX40). This hOX40 aptamer was isolated using systematic evolution of ligands by exponential enrichment and binds the target purified protein with high affinity [dissociation constants (K(d))<10 nM]. Moreover, the hOX40 aptamer-streptavidin complex has an apparent binding affinity of ~50 nM for hOX40 on activated T cells as determined by flow cytometry and specifically binds activated human T cells. A multivalent version of the aptamer, but not a mutant version of the aptamer, was able to stimulate OX40 on T cells and enhance cell proliferation and interferon-gamma production. Future studies will assess the therapeutic potential of hOX40 aptamers for ex vivo stimulation of antigen specific T cells in conjunction with dendritic cell-based vaccines for adoptive cellular therapy.

Authors
Pratico, ED; Sullenger, BA; Nair, SK
MLA Citation
Pratico, ED, Sullenger, BA, and Nair, SK. "Identification and characterization of an agonistic aptamer against the T cell costimulatory receptor, OX40." Nucleic Acid Ther 23.1 (February 2013): 35-43.
PMID
23113766
Source
pubmed
Published In
Nucleic Acid Therapeutics
Volume
23
Issue
1
Publish Date
2013
Start Page
35
End Page
43
DOI
10.1089/nat.2012.0388

Immunologic targeting of FOXP3 in inflammatory breast cancer cells.

The forkhead transcription factor FOXP3 is necessary for induction of regulatory T lymphocytes (Tregs) and their immunosuppressive function. We have previously demonstrated that targeting Tregs by vaccination of mice with murine FOXP3 mRNA-transfected dendritic cells (DCs) elicits FOXP3-specific T cell responses and enhances tumor immunity. It is clear that FOXP3 expression is not restricted to T-cell lineage and herein, using RT-PCR, flow cytometry, and western immunoblot we demonstrate for the first time that FOXP3 is expressed in inflammatory breast cancer (IBC) cells, SUM149 (triple negative, ErbB1-activated) and SUM190 (ErbB2-overexpressing). Importantly, FOXP3-specific T cells generated in vitro using human FOXP3 RNA-transfected DCs as stimulators efficiently lyse SUM149 cells. Interestingly, an isogenic model (rSUM149) derived from SUM149 with an enhanced anti-apoptotic phenotype was resistant to FOXP3-specific T cell mediated lysis. The MHC class I cellular processing mechanism was intact in both cell lines at the protein and transcription levels suggesting that the resistance to cytolysis by rSUM149 cells was not related to MHC class I expression or to the MHC class I antigen processing machinery in these cells. Our data suggest that FOXP3 may be an effective tumor target in IBC cells however increased anti-apoptotic signaling can lead to immune evasion.

Authors
Nair, S; Aldrich, AJ; McDonnell, E; Cheng, Q; Aggarwal, A; Patel, P; Williams, MM; Boczkowski, D; Lyerly, HK; Morse, MA; Devi, GR
MLA Citation
Nair, S, Aldrich, AJ, McDonnell, E, Cheng, Q, Aggarwal, A, Patel, P, Williams, MM, Boczkowski, D, Lyerly, HK, Morse, MA, and Devi, GR. "Immunologic targeting of FOXP3 in inflammatory breast cancer cells." PLoS One 8.1 (2013): e53150-.
PMID
23341929
Source
pubmed
Published In
PloS one
Volume
8
Issue
1
Publish Date
2013
Start Page
e53150
DOI
10.1371/journal.pone.0053150

Programming human dendritic cells with mRNA.

Transfecting with in vitro transcribed, protein-encoding mRNA is a simple yet effective method to express high levels of the desired RNA-encoded proteins in primary cells. Cells can be transfected with antigen-encoding mRNA, which is translated into protein and is processed by the cellular antigen-processing pathway to generate antigen-presenting cells. Another elegant and increasingly popular application is to transfect cells with mRNA that encodes immune modulating molecules (cytokines, chemokines, toll-like receptors (TLRs), immune receptor ligands, immune receptor targeting antibodies) which, when translated into protein, can program cell behavior and/or function. In this chapter we describe an efficient method to deliver mRNA into human dendritic cells (DCs) by electroporation. This is currently the method of choice to deliver mRNA into antigen-presenting cells for generating vaccines for cancer immunotherapy.

Authors
Lee, J; Boczkowski, D; Nair, S
MLA Citation
Lee, J, Boczkowski, D, and Nair, S. "Programming human dendritic cells with mRNA." Methods Mol Biol 969 (2013): 111-125. (Review)
PMID
23296931
Source
pubmed
Published In
Methods in molecular biology (Clifton, N.J.)
Volume
969
Publish Date
2013
Start Page
111
End Page
125
DOI
10.1007/978-1-62703-260-5_8

Engineering B cells with mRNA.

Ex vivo activated B cells are an alternative source of antigen presenting cells (APC). However, the ability of ex vivo activated B cells to function as potent APCs has been a concern especially when compared to dendritic cells (DC). Herein, we introduce a strategy to modulate antigen presentation and immune stimulation functions of activated B cells by co-transfection with multiple mRNAs encoding costimulatory molecules (OX40L, 4-1BBL, and CD80), cytokines (IL-12p35 and IL-12p40) and antigen. These activated B cells modified to express immune stimulatory molecules can be a potent alternative to DCs in immunotherapy.

Authors
Lee, J; Boczkowski, D; Nair, S
MLA Citation
Lee, J, Boczkowski, D, and Nair, S. "Engineering B cells with mRNA." Methods Mol Biol 969 (2013): 101-110. (Review)
PMID
23296930
Source
pubmed
Published In
Methods in molecular biology (Clifton, N.J.)
Volume
969
Publish Date
2013
Start Page
101
End Page
110
DOI
10.1007/978-1-62703-260-5_7

Melanoma immunotherapy using mature DCs expressing the constitutive proteasome

Background. Many cancers, including melanoma, exclusively express constitutive proteasomes (cPs) and are unable to express immunoproteasomes (iPs). In contrast, mature DCs used for immunotherapy exclusively express iPs. Since proteasomes generate peptides presented by HLA class I molecules, we hypothesized that mature melanoma antigen-loaded DCs engineered to process antigens through cPs would be superior inducers of antimelanoma immunity in vivo. Methods. Subjects with metastatic melanoma were vaccinated with mature DCs transfected with RNAs encoding melanoma antigens MART1, MAGE-3, gp100, and tyrosinase. These DCs were derived from monocytes that were untransfected (Arm A; n = 4), transfected with control siRNA (Arm B; n = 3), or transfected with siRNAs targeting the 3 inducible iP subunits (Arm C; n = 5). Results. Vaccination stimulated antigen-specific T cell responses in all subjects, which peaked after 3-4 vaccinations, but remained elevated in Arm C subjects. Also in Arm C, circulating melanoma cell levels (as detected by quantitative PCR) fell, and T cell lytic activity against autologous melanoma was induced. In HLA-A2+ subjects, CD8+ T cells that bound tetramers loaded with cP-derived melanoma antigenic peptides were found in the peripheral blood only in Arm C subjects. Of 2 subjects with active disease (both in Arm C), one had a partial clinical response, while the other, who exhibited diffuse dermal and soft tissue metastases, had a complete response. Conclusion. These results suggest that the efficacy of melanoma DC-based immunotherapy is enhanced when tumor antigen-loaded DCs used for vaccination express cPs. Trial registration. Clinicaltrials.gov NCT00672542.

Authors
Dannull, J; Haley, NR; Archer, G; Nair, S; Boczkowski, D; Harper, M; Rosa, ND; Pickett, N; Mosca, PJ; Burchette, J; Selim, MA; Mitchell, DA; Sampson, J; Tyler, DS; Pruitt, SK
MLA Citation
Dannull, J, Haley, NR, Archer, G, Nair, S, Boczkowski, D, Harper, M, Rosa, ND, Pickett, N, Mosca, PJ, Burchette, J, Selim, MA, Mitchell, DA, Sampson, J, Tyler, DS, and Pruitt, SK. "Melanoma immunotherapy using mature DCs expressing the constitutive proteasome." Journal of Clinical Investigation 123.7 (2013): 3135-3145.
PMID
23934126
Source
scival
Published In
Journal of Clinical Investigation
Volume
123
Issue
7
Publish Date
2013
Start Page
3135
End Page
3145
DOI
10.1172/JCI67544

Isolation and generation of human dendritic cells.

Dendritic cells are highly specialized antigen-presenting cells (APC), which may be isolated or generated from human blood mononuclear cells. Although mature blood dendritic cells normally represent ∼0.2% of human blood mononuclear cells, their frequency can be greatly increased using the cell enrichment methods described in this unit. More highly purified dendritic cell preparations can be obtained from these populations by sorting of fluorescence-labeled cells. Alternatively, dendritic cells can be generated from monocytes by culture with the appropriate cytokines, as described here. In addition, a negative selection approach is provided that may be employed to generate cell preparations that have been depleted of dendritic cells to be used for comparison in functional studies.

Authors
Nair, S; Archer, GE; Tedder, TF
MLA Citation
Nair, S, Archer, GE, and Tedder, TF. "Isolation and generation of human dendritic cells." Curr Protoc Immunol Chapter 7 (November 2012): Unit7.32-.
PMID
23129155
Source
pubmed
Published In
Current Protocols in Immunology
Volume
Chapter 7
Publish Date
2012
Start Page
Unit7.32
DOI
10.1002/0471142735.im0732s99

A pilot study of IL-2Rα blockade during lymphopenia depletes regulatory T-cells and correlates with enhanced immunity in patients with glioblastoma.

BACKGROUND: Preclinical studies in mice have demonstrated that the prophylactic depletion of immunosuppressive regulatory T-cells (T(Regs)) through targeting the high affinity interleukin-2 (IL-2) receptor (IL-2Rα/CD25) can enhance anti-tumor immunotherapy. However, therapeutic approaches are complicated by the inadvertent inhibition of IL-2Rα expressing anti-tumor effector T-cells. OBJECTIVE: To determine if changes in the cytokine milieu during lymphopenia may engender differential signaling requirements that would enable unarmed anti-IL-2Rα monoclonal antibody (MAbs) to selectively deplete T(Regs) while permitting vaccine-stimulated immune responses. METHODOLOGY: A randomized placebo-controlled pilot study was undertaken to examine the ability of the anti-IL-2Rα MAb daclizumab, given at the time of epidermal growth factor receptor variant III (EGFRvIII) targeted peptide vaccination, to safely and selectively deplete T(Regs) in patients with glioblastoma (GBM) treated with lymphodepleting temozolomide (TMZ). RESULTS AND CONCLUSIONS: Daclizumab treatment (n = 3) was well-tolerated with no symptoms of autoimmune toxicity and resulted in a significant reduction in the frequency of circulating CD4+Foxp3+ TRegs in comparison to saline controls (n = 3)( p = 0.0464). A significant (p<0.0001) inverse correlation between the frequency of TRegs and the level of EGFRvIII specific humoral responses suggests the depletion of TRegs may be linked to increased vaccine-stimulated humoral immunity. These data suggest this approach deserves further study. TRIAL REGISTRATION: ClinicalTrials.gov NCT00626015.

Authors
Sampson, JH; Schmittling, RJ; Archer, GE; Congdon, KL; Nair, SK; Reap, EA; Desjardins, A; Friedman, AH; Friedman, HS; Herndon, JE; Coan, A; McLendon, RE; Reardon, DA; Vredenburgh, JJ; Bigner, DD; Mitchell, DA
MLA Citation
Sampson, JH, Schmittling, RJ, Archer, GE, Congdon, KL, Nair, SK, Reap, EA, Desjardins, A, Friedman, AH, Friedman, HS, Herndon, JE, Coan, A, McLendon, RE, Reardon, DA, Vredenburgh, JJ, Bigner, DD, and Mitchell, DA. "A pilot study of IL-2Rα blockade during lymphopenia depletes regulatory T-cells and correlates with enhanced immunity in patients with glioblastoma." PLoS One 7.2 (2012): e31046-.
PMID
22383993
Source
pubmed
Published In
PloS one
Volume
7
Issue
2
Publish Date
2012
Start Page
e31046
DOI
10.1371/journal.pone.0031046

Enhancement of anti-tumor immunity through local modulation of CTLA-4 and GITR by dendritic cells.

Cancer vaccines have now demonstrated clinical efficacy, but immune modulatory mechanisms that prevent autoimmunity limit their effectiveness. Systemic administration of mAbs targeting the immune modulatory receptors CTLA-4 and glucocorticoid-induced TNFR-related protein (GITR) on Treg and effector T cells augments anti-tumor immunity both experimentally and clinically, but can induce life-threatening autoimmunity. We hypothesized that local delivery of anti-CTLA-4 and anti-GITR mAbs to the sites where T cells and tumor antigen-loaded DC vaccines interact would enhance the induction of anti-tumor immunity while avoiding autoimmunity. To achieve this goal, DCs transfected with mRNA encoding the H and L chains of anti-mouse CTLA-4 and GITR mAbs were co-administered with tumor antigen mRNA-transfected DCs. We observed enhanced induction of anti-tumor immunity and significantly improved survival in melanoma-bearing mice, without signs of autoimmunity. Using in vitro assays with human DCs, we demonstrated that DCs transfected with mRNA encoding a humanized anti-CTLA-4 mAb and mRNA encoding a soluble human GITR-L fusion protein enhance the induction of anti-tumor CTLs in response to DCs transfected with mRNAs encoding either melanoma or breast cancer antigens. Based on these results, this approach of using local delivery of immune modulators to enhance vaccine-induced immunity is currently being evaluated in a phase I clinical cancer immunotherapy trial.

Authors
Pruitt, SK; Boczkowski, D; de Rosa, N; Haley, NR; Morse, MA; Tyler, DS; Dannull, J; Nair, S
MLA Citation
Pruitt, SK, Boczkowski, D, de Rosa, N, Haley, NR, Morse, MA, Tyler, DS, Dannull, J, and Nair, S. "Enhancement of anti-tumor immunity through local modulation of CTLA-4 and GITR by dendritic cells." Eur J Immunol 41.12 (December 2011): 3553-3563.
PMID
22028176
Source
pubmed
Published In
European Journal of Immunology
Volume
41
Issue
12
Publish Date
2011
Start Page
3553
End Page
3563
DOI
10.1002/eji.201141383

CYTOMEGALOVIRUS-SPECIFIC IMMUNE DEFICITS IN PATIENTS WITH GBM

Authors
Johnson, LA; Archer, GE; Nair, SK; Schmittling, R; Reap, E; Sampson, JH
MLA Citation
Johnson, LA, Archer, GE, Nair, SK, Schmittling, R, Reap, E, and Sampson, JH. "CYTOMEGALOVIRUS-SPECIFIC IMMUNE DEFICITS IN PATIENTS WITH GBM." November 2011.
Source
wos-lite
Published In
Neuro-Oncology
Volume
13
Publish Date
2011
Start Page
39
End Page
39

RNA as performance-enhancers for dendritic cells

Importance of the field: Although studies have demonstrated that antigen-loaded dendritic cells (DC) elicit antigen-specific immune responses, the clinical benefit from DC-based cancer immunotherapy remains low. RNA, in the form of mRNA, has not only been used as a source of antigen but more recently as a way to stimulate DC to produce immunostimulatory molecules. As siRNA it has allowed researchers to modify DC to produce a favorable cytokine profile or to present antigen that may generate the desired immune response. Areas covered in this review: When loading DC with RNA that encodes immunostimulatory protein, rather than a source of antigen, optimal translation and efficient transfection into DC are critical. Studies addressing these issues and the functional consequences of modulating DC function are reviewed. What the reader will gain: RNA can be used to load DC with antigen and to encode proteins that will enhance the immune response. Co-transfection with multiple mRNAs or mRNA plus siRNA can significantly improve vaccine efficacy. Take home message: One conclusion from Phase I clinical trials with DC loaded with tumor antigen is that tumor-specific induction of immune responses is not sufficient to destroy pre-established tumors. The advantage of transfection with mRNA is the ability to load DC with antigen-encoding mRNA and immunostimulatory protein-encoding mRNA to achieve the desired clinical response. © 2010 Informa UK Ltd.

Authors
Boczkowski, D; Nair, S
MLA Citation
Boczkowski, D, and Nair, S. "RNA as performance-enhancers for dendritic cells." Expert Opinion on Biological Therapy 10.4 (2010): 563-574.
PMID
20128707
Source
scival
Published In
Expert Opinion on Biological Therapy
Volume
10
Issue
4
Publish Date
2010
Start Page
563
End Page
574
DOI
10.1517/14712591003614749

Dendritic cells engineered to secrete anti-GITR antibodies are effective adjuvants to dendritic cell-based immunotherapy.

A number of monoclonal antibodies (mAbs) have been studied for their ability to enhance immune responses. Although these antibodies are effective in pre-clinical and clinical studies, they are costly and have occasionally been associated with adverse effects such as autoimmunity and cytokine storm. Numerous studies have shown that treatment of mice with an agonistic mAb, clone DTA-1, targeting murine glucocorticoid-induced tumor necrosis factor receptor (GITR) results in enhanced immune responses in tumor-bearing animals. Herein, we evaluate the novel approach of transfecting dendritic cell (DC) with mRNA encoding the heavy and light chain of the anti-GITR mAb. We show the induction of significantly enhanced tumor immunity by vaccinating with a combination of anti-GITR-secreting DC and tumor antigen-presenting DC. This enhancement is comparable to that seen with systemically delivered mAb along with the antigen-presenting DC. Importantly, when anti-GITR was delivered using RNA-transfected DC, we observed no evidence of autoimmune hypopigmentation in any tumor-free mice. We also show enhanced induction of cytotoxic T-lymphocyte responses, which is only observed when the antigen-presenting and antibody-secreting DC are co-injected at the same site. To illustrate the broad utility of this strategy, we show that DC transfected with mRNA encoding GITR-ligand/Fc fusion protein is also an effective tumor vaccine adjuvant.

Authors
Boczkowski, D; Lee, J; Pruitt, S; Nair, S
MLA Citation
Boczkowski, D, Lee, J, Pruitt, S, and Nair, S. "Dendritic cells engineered to secrete anti-GITR antibodies are effective adjuvants to dendritic cell-based immunotherapy." Cancer Gene Ther 16.12 (December 2009): 900-911.
PMID
19498460
Source
pubmed
Published In
Cancer Gene Therapy
Volume
16
Issue
12
Publish Date
2009
Start Page
900
End Page
911
DOI
10.1038/cgt.2009.39

Activated B cells modified by electroporation of multiple mRNAs encoding immune stimulatory molecules are comparable to mature dendritic cells in inducing in vitro antigen-specific T-cell responses.

Ex-vivo-activated B cells are an alternative source of antigen-presenting cells (APCs) and a potential replacement for dendritic cells (DCs) in immunotherapy. However, the ability of ex-vivo-activated B cells to function as potent APCs has been a concern, especially when compared to DCs. Our study investigated whether modification of activated B cells with immune stimulatory molecules could enhance the ability of activated B cells to stimulate T cells. We show that murine splenic B cells, activated with a combination of Toll-like receptor agonist and agonistic anti-CD40, stimulated antigen-specific CD8+ T cells more efficiently than cells activated with Toll-like receptor agonist or anti-CD40 alone, probably by down-regulation of the immune regulatory cytokine interleukin-10 (IL-10). However, the activated B cells were still poor T-cell stimulators compared to mature DCs. Therefore, we modified the activated B cells by simultaneous electroporation of multiple messenger RNAs encoding costimulatory molecules (OX40L and 4-1BBL), cytokines (IL-12p35 and IL-12p40) and antigen. We found that de novo expression or overexpression of OX40L, 4-1BBL and IL-12p70 on activated B cells synergistically enhanced proliferation as well as IL-2 and interferon-gamma production by CD8+ T cells. Furthermore, the RNA-modified activated B cells induced antigen-specific cytotoxic T lymphocyte responses as efficiently as mature DCs in vitro. Unexpectedly, modified activated B cells were inferior to mature DCs at in vivo induction of CD8+ T-cell responses. In summary, activated B cells modified to express immune stimulatory molecules are a potent alternative to DCs in immunotherapy.

Authors
Lee, J; Dollins, CM; Boczkowski, D; Sullenger, BA; Nair, S
MLA Citation
Lee, J, Dollins, CM, Boczkowski, D, Sullenger, BA, and Nair, S. "Activated B cells modified by electroporation of multiple mRNAs encoding immune stimulatory molecules are comparable to mature dendritic cells in inducing in vitro antigen-specific T-cell responses." Immunology 125.2 (October 2008): 229-240.
PMID
18393968
Source
pubmed
Published In
Immunology
Volume
125
Issue
2
Publish Date
2008
Start Page
229
End Page
240
DOI
10.1111/j.1365-2567.2008.02833.x

Assembling OX40 aptamers on a molecular scaffold to create a receptor-activating aptamer.

We show that a molecular scaffold can be utilized to convert a receptor binding aptamer into a receptor agonist. Many receptors (including tumor necrosis receptor family members) are activated when they are multimerized on the cell surface. Molecular scaffolds have been utilized to assemble multiple receptor binding peptide ligands to generate activators of such receptors. We demonstrate that an RNA aptamer that recognizes OX40, a member of the tumor necrosis factor receptor superfamily, can be converted into a receptor-activating aptamer by assembling two copies on an olignucleotide-based scaffold. The OX40 receptor-activating aptamer is able to induce nuclear localization of nuclear factor-kappaB, cytokine production, and cell proliferation, as well as enhance the potency of dendritic cell-based tumor vaccines when systemically delivered to mice.

Authors
Dollins, CM; Nair, S; Boczkowski, D; Lee, J; Layzer, JM; Gilboa, E; Sullenger, BA
MLA Citation
Dollins, CM, Nair, S, Boczkowski, D, Lee, J, Layzer, JM, Gilboa, E, and Sullenger, BA. "Assembling OX40 aptamers on a molecular scaffold to create a receptor-activating aptamer." Chem Biol 15.7 (July 21, 2008): 675-682.
PMID
18635004
Source
pubmed
Published In
Chemistry & Biology
Volume
15
Issue
7
Publish Date
2008
Start Page
675
End Page
682
DOI
10.1016/j.chembiol.2008.05.016

Aptamers in immunotherapy.

Authors
Dollins, CM; Nair, S; Sullenger, BA
MLA Citation
Dollins, CM, Nair, S, and Sullenger, BA. "Aptamers in immunotherapy." Hum Gene Ther 19.5 (May 2008): 443-450. (Review)
PMID
18473674
Source
pubmed
Published In
Human Gene Therapy
Volume
19
Issue
5
Publish Date
2008
Start Page
443
End Page
450
DOI
10.1089/hum.2008.045

Vaccination against the forkhead family transcription factor Foxp3 enhances tumor immunity.

Depletion of CD4+CD25+ regulatory T cells (Treg) by treatment with alphaCD25 antibody synergizes with vaccination protocols to engender protective immunity in mice. The effectiveness of targeting CD25 to eliminate Treg is limited by the fact that CD25, the low-affinity interleukin-2 receptor, is up-regulated on conventional T cells. At present, foxp3 is the only product known to be exclusively expressed in Treg of mice. However, foxp3 is not expressed on the cell surface and hence cannot be targeted with antibodies. In this study, we tested the hypothesis that vaccination of mice against foxp3, a self-antigen expressed also in the thymus, is capable of stimulating foxp3-specific CTL that will cause the depletion of Treg and enhanced antitumor immunity. Vaccination of mice with foxp3 mRNA-transfected dendritic cells elicited a robust foxp3-specific CTL response and potentiated vaccine-induced protective immunity comparably with that of alphaCD25 antibody administration. In contrast to alphaCD25 antibody treatment, repeated foxp3 vaccination did not interfere with vaccine-induced protective immunity. Importantly, foxp3 vaccination led to the preferential depletion of foxp3-expressing Treg in the tumor but not in the periphery, whereas alphaCD25 antibody treatment led to depletion of Treg in both the tumor and the periphery. Targeting foxp3 by vaccination offers a specific and simpler protocol for the prolonged control of Treg that may be associated with reduced risk of autoimmunity, introducing an approach whereby specific depletion of cells is not limited to targeting products expressed on the cell surface.

Authors
Nair, S; Boczkowski, D; Fassnacht, M; Pisetsky, D; Gilboa, E
MLA Citation
Nair, S, Boczkowski, D, Fassnacht, M, Pisetsky, D, and Gilboa, E. "Vaccination against the forkhead family transcription factor Foxp3 enhances tumor immunity." Cancer Res 67.1 (January 1, 2007): 371-380.
PMID
17210720
Source
pubmed
Published In
Cancer Research
Volume
67
Issue
1
Publish Date
2007
Start Page
371
End Page
380
DOI
10.1158/0008-5472.CAN-06-2903

Systemic anti-CD25 monoclonal antibody administration safely enhances immunity in murine glioma without eliminating regulatory T cells.

PURPOSE: Elevated proportions of regulatory T cells (T(reg)) are present in patients with a variety of cancers, including malignant glioma, yet recapitulative murine models are wanting. We therefore examined T(regs) in mice bearing malignant glioma and evaluated anti-CD25 as an immunotherapeutic adjunct. EXPERIMENTAL DESIGN: CD4+CD25+Foxp3+GITR+ T(regs) were quantified in the peripheral blood, spleens, cervical lymph nodes, and bone marrow of mice bearing malignant glioma. The capacities for systemic anti-CD25 therapy to deplete T(regs), enhance lymphocyte function, and generate antiglioma CTL responses were assessed. Lastly, survival and experimental allergic encephalitis risks were evaluated when anti-CD25 was combined with a dendritic cell-based immunization targeting shared tumor and central nervous system antigens. RESULTS: Similar to patients with malignant glioma, glioma-bearing mice show a CD4 lymphopenia. Additionally, CD4+CD25+Foxp3+GITR+ T(regs) represent an increased fraction of the remaining peripheral blood CD4+ T cells, despite themselves being reduced in number. Similar trends are observed in cervical lymph node and spleen, but not in bone marrow. Systemic anti-CD25 administration hinders detection of CD25+ cells but fails to completely eliminate T(regs), reducing their number only moderately, yet eliminating their suppressive function. This elimination of T(reg) function permits enhanced lymphocyte proliferative and IFN-gamma responses and up to 80% specific lysis of glioma cell targets in vitro. When combined with dendritic cell immunization, anti-CD25 elicits tumor rejection in 100% of challenged mice without precipitating experimental allergic encephalitis. CONCLUSIONS: Systemic anti-CD25 administration does not entirely eliminate T(regs) but does prevent T(reg) function. This leads to safe enhancement of tumor immunity in a murine glioma model that recapitulates the tumor-induced changes to the CD4 and T(reg) compartments seen in patients with malignant glioma.

Authors
Fecci, PE; Sweeney, AE; Grossi, PM; Nair, SK; Learn, CA; Mitchell, DA; Cui, X; Cummings, TJ; Bigner, DD; Gilboa, E; Sampson, JH
MLA Citation
Fecci, PE, Sweeney, AE, Grossi, PM, Nair, SK, Learn, CA, Mitchell, DA, Cui, X, Cummings, TJ, Bigner, DD, Gilboa, E, and Sampson, JH. "Systemic anti-CD25 monoclonal antibody administration safely enhances immunity in murine glioma without eliminating regulatory T cells." Clinical cancer research : an official journal of the American Association for Cancer Research 12.14 Pt 1 (July 2006): 4294-4305.
PMID
16857805
Source
epmc
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
12
Issue
14 Pt 1
Publish Date
2006
Start Page
4294
End Page
4305
DOI
10.1158/1078-0432.ccr-06-0053

Vaccination with mRNAs encoding tumor-associated antigens and granulocyte-macrophage colony-stimulating factor efficiently primes CTL responses, but is insufficient to overcome tolerance to a model tumor/self antigen.

Immunization of mice with dendritic cells transfected ex vivo with tumor-associated antigen (TAA)-encoding mRNA primes cytotoxic T lymphocytes (CTL) that mediate tumor rejection. Here we investigated whether direct injection of TAA mRNA, encapsulated in cationic liposomes, could function similarly as cancer immunotherapy. Intradermal and intravenous injection of ovalbumin (OVA) mRNA generated specific CTL activity and inhibited the growth of OVA-expressing tumors. Vaccination studies with DNA have demonstrated that co-administration of antigen (Ag)- and cytokine-encoding plasmids potentiate the T cell response; in analogous fashion, the inclusion of granulocyte-macrophage colony-stimulating factor (GM-CSF) mRNA enhanced OVA-specific cytotoxicity. The ability of this GM-CSF-augmented mRNA vaccine to treat an established spontaneous tumor was evaluated in the Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) mouse, using the SV40 large T Ag (TAg) as a model tumor/self Ag. Repeated vaccination elicited vigorous TAg-specific CTL activity in nontransgenic mice, but tumor-bearing TRAMP mice remained tolerant. Adoptive transfer of naïve splenocytes into TRAMP mice prior to the first vaccination restored TAg reactivity, and slowed tumor progression. The data from this study suggests that vaccination with TAA mRNA is a simple and effective means of priming antitumor CTL, and that immunogenicity of the vaccine can be augmented by co-delivery of GM-CSF mRNA. Nonetheless, limitations of such vaccines in overcoming tolerance to tumor/self Ag may mandate prior or simultaneous reconstitution of the autoreactive T cell repertoire for this form of immunization to be effective.

Authors
Hess, PR; Boczkowski, D; Nair, SK; Snyder, D; Gilboa, E
MLA Citation
Hess, PR, Boczkowski, D, Nair, SK, Snyder, D, and Gilboa, E. "Vaccination with mRNAs encoding tumor-associated antigens and granulocyte-macrophage colony-stimulating factor efficiently primes CTL responses, but is insufficient to overcome tolerance to a model tumor/self antigen." Cancer Immunol Immunother 55.6 (June 2006): 672-683.
PMID
16133108
Source
pubmed
Published In
Cancer Immunology, Immunotherapy
Volume
55
Issue
6
Publish Date
2006
Start Page
672
End Page
683
DOI
10.1007/s00262-005-0064-z

Tumor immunotherapy targeting fibroblast activation protein, a product expressed in tumor-associated fibroblasts.

Murine studies have shown that immunologic targeting of the tumor vasculature, a key element of the tumor stroma, can lead to protective immunity in the absence of significant pathology. In the current study, we expand the scope of stroma-targeted immunotherapy to antigens expressed in tumor-associated fibroblasts, the predominant component of the stroma in most types of cancer. Mice were immunized against fibroblast activation protein (FAP), a product up-regulated in tumor-associated fibroblasts, using dendritic cells transfected with FAP mRNA. Using melanoma, carcinoma, and lymphoma models, we show that tumor growth was inhibited in tumor-bearing mice vaccinated against FAP and that the magnitude of the antitumor response was comparable to that of vaccination against tumor cell-expressed antigens. Both s.c. implanted tumors and lung metastases were susceptible to anti-FAP immunotherapy. The antitumor response could be further enhanced by augmenting the CD4+ T-cell arm of the anti-FAP immune response, achieved by using a lysosomal targeting sequence to redirect the translated FAP product into the class II presentation pathway, or by covaccination against FAP and a tumor cell-expressed antigen, tyrosinase-related protein 2. No morbidity or mortality was associated with anti-FAP vaccination except for a small delay in wound healing. The study suggests that FAP, a product which is preferentially expressed in tumor-associated fibroblasts, could function as a tumor rejection antigen in a broad range of cancers.

Authors
Lee, J; Fassnacht, M; Nair, S; Boczkowski, D; Gilboa, E
MLA Citation
Lee, J, Fassnacht, M, Nair, S, Boczkowski, D, and Gilboa, E. "Tumor immunotherapy targeting fibroblast activation protein, a product expressed in tumor-associated fibroblasts." Cancer Res 65.23 (December 1, 2005): 11156-11163.
PMID
16322266
Source
pubmed
Published In
Cancer Research
Volume
65
Issue
23
Publish Date
2005
Start Page
11156
End Page
11163
DOI
10.1158/0008-5472.CAN-05-2805

Induction of CD4(+) and CD8(+) T-cell responses to the human stromal antigen, fibroblast activation protein: implication for cancer immunotherapy.

PURPOSE: The propensity of tumor cells to escape immune elimination could limit, if not defeat, the long-term benefits of effective immunotherapeutic protocols. Immunologic targeting of tumor stroma could significantly reduce the ability of tumors to evade immune elimination. Murine studies have shown that inducing immunity against angiogenesis-associated products engenders potent antitumor immunity without significant pathology. It is, however, not known whether T cells corresponding to stromal products are present in humans. In this study, we describe a method to screen for human stromal products that have not triggered significant tolerance and could therefore serve as candidate antigens for cancer immunotherapy. EXPERIMENTAL DESIGN: To identify candidates for human stromal antigens, we used an in vitro-screening method to determine whether dendritic cells transfected with mRNA encoding products, which are overexpressed in the tumor stroma, are capable of stimulating cytotoxic CD8(+) (CTL) responses from human peripheral blood mononuclear cells. RESULTS: CTL responses could be consistently generated against fibroblast activation protein (FAP) but not against matrix metalloproteinase-9 (MMP-9) or MMP-14. To enhance the immunogenicity of the mRNA-translated FAP product, a lysosomal targeting signal derived from lysosome-associated membrane protein-1 (LAMP-1) was fused to the COOH terminus of FAP to redirect the translated product into the class II presentation pathway. Dendritic cells transfected with mRNA encoding the FAP-LAMP fusion product stimulated enhanced CD4(+) and CD8(+) T-cell responses. CONCLUSION: This study identifies FAP, a protease preferentially expressed in tumor-associated fibroblasts, as a candidate human stromal antigen to target in the setting of cancer immunotherapy, and shows that differential expression of stromal products is not a sufficient criteria to indicate its immunogenicity in a vaccination setting.

Authors
Fassnacht, M; Lee, J; Milazzo, C; Boczkowski, D; Su, Z; Nair, S; Gilboa, E
MLA Citation
Fassnacht, M, Lee, J, Milazzo, C, Boczkowski, D, Su, Z, Nair, S, and Gilboa, E. "Induction of CD4(+) and CD8(+) T-cell responses to the human stromal antigen, fibroblast activation protein: implication for cancer immunotherapy." Clin Cancer Res 11.15 (August 1, 2005): 5566-5571.
PMID
16061874
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
11
Issue
15
Publish Date
2005
Start Page
5566
End Page
5571
DOI
10.1158/1078-0432.CCR-05-0699

Enhancing the immunostimulatory function of dendritic cells by transfection with mRNA encoding OX40 ligand.

The objective of this study was to investigate whether the immunostimulatory properties of human monocyte-derived dendritic cells (DCs) could be enhanced by triggering OX40/OX40L signaling. Since monocyte-derived DCs possess only low-cell surface levels of OX40L in the absence of CD40 signaling, OX40L was expressed by transfection of DCs with the corresponding mRNA. We show that OX40L mRNA transfection effectively enhanced the immunostimulatory function of DCs at multiple levels: OX40L mRNA transfection augmented allogeneic and HLA class II epitope-specific CD4+ T-cell responses, improved the stimulation of antigen-specific cytotoxic T lymphocytes (CTLs) in vitro without interfering with the prostaglandin E2 (PGE2)-mediated migratory function of the DCs, and facilitated interleukin 12 p70 (IL-12p70)-independent T helper type 1 (Th1) polarization of naive CD4+ T-helper cells. Furthermore, vaccination of tumor-bearing mice using OX40L mRNA-cotransfected DCs resulted in significant enhancement of therapeutic antitumor immunity due to in vivo priming of Th1-type T-cell responses. Our data suggest that transfection of DCs with OX40L mRNA may represent a promising strategy that could be applied in clinical immunotherapy protocols, while circumventing the current unavailability of reagents facilitating OX40 ligation.

Authors
Dannull, J; Nair, S; Su, Z; Boczkowski, D; DeBeck, C; Yang, B; Gilboa, E; Vieweg, J
MLA Citation
Dannull, J, Nair, S, Su, Z, Boczkowski, D, DeBeck, C, Yang, B, Gilboa, E, and Vieweg, J. "Enhancing the immunostimulatory function of dendritic cells by transfection with mRNA encoding OX40 ligand." Blood 105.8 (April 15, 2005): 3206-3213.
PMID
15618466
Source
pubmed
Published In
Blood
Volume
105
Issue
8
Publish Date
2005
Start Page
3206
End Page
3213
DOI
10.1182/blood-2004-10-3944

Induction of human dendritic cell maturation using transfection with RNA encoding a dominant positive toll-like receptor 4.

Maturation of dendritic cells (DC) is critical for the induction of Ag-specific immunity. Ag-loaded DC matured with LPS, which mediates its effects by binding to Toll-like receptor 4 (TLR4), induce Ag-specific CTL in vitro and in vivo in animal models. However, clinical use of LPS is limited due to potential toxicity. Therefore, we sought to mimic the maturation-inducing effects of LPS on DC by stimulating TLR4-mediated signaling in the absence of exogenous LPS. We developed a constitutively active TLR4 (caTLR4) and demonstrated that transfection of human DC with RNA encoding caTLR4 led to IL-12 and TNF-alpha secretion. Transfection with caTLR4 RNA also induced a mature DC phenotype. Functionally, transfection of DC with caTLR4 RNA enhanced allostimulation of CD4(+) T cells. DC transfected with RNA encoding the MART (Melan-A/MART-1) melanoma Ag were then used to stimulate T cells in vitro. Cotransfection of these DC with caTLR4 RNA enhanced the generation of MART-specific CTL. This CTL activity was superior to that seen when DC maturation was induced using either LPS or a standard mixture of cytokines (TNF-alpha, IL-6, IL-1beta, and PGE(2)). We conclude that transfection of DC with RNA encoding a functional signaling protein, such as caTLR4, may provide a new tool for studying TLR signaling in DC and may be a promising approach for the induction of DC maturation for tumor immunotherapy.

Authors
Cisco, RM; Abdel-Wahab, Z; Dannull, J; Nair, S; Tyler, DS; Gilboa, E; Vieweg, J; Daaka, Y; Pruitt, SK
MLA Citation
Cisco, RM, Abdel-Wahab, Z, Dannull, J, Nair, S, Tyler, DS, Gilboa, E, Vieweg, J, Daaka, Y, and Pruitt, SK. "Induction of human dendritic cell maturation using transfection with RNA encoding a dominant positive toll-like receptor 4." J Immunol 172.11 (June 1, 2004): 7162-7168.
PMID
15153540
Source
pubmed
Published In
Journal of immunology (Baltimore, Md. : 1950)
Volume
172
Issue
11
Publish Date
2004
Start Page
7162
End Page
7168

Transfection of RNA encoding tumor antigens following maturation of dendritic cells leads to prolonged presentation of antigen and the generation of high-affinity tumor-reactive cytotoxic T lymphocytes.

Common tumor vaccination strategies utilizing peptide-pulsed dendritic cells (DC) are limited to targeting antigens with known epitopes in patients expressing a defined restricting allele and can result in the preferential induction of low-avidity T cells that fail to recognize tumor cells. The use of dendritic cells transfected with RNA encoding tumor antigen offers the prospect of antigen-specific immunization without requiring prior knowledge of the immunogenic epitope or restricting allele, since epitopes from the translated protein are processed by the endogenous antigen-presentation machinery. However, its use in vaccine studies has been limited by low RNA transfection efficiency and the use of immature DC as recipient cells. In this study, we report an RNA transfection strategy that routinely achieves expression in 40-50% of mature DC, which are better stimulator cells. Such RNA-transfected mature DC exhibited a prolonged duration of presentation of immunogenic epitopes compared to peptide-pulsed DC, induced greater frequencies of tumor antigen-specific CTL, and generated a CTL population that exhibited higher target avidity and increased tumor lytic capacity. These studies provide compelling in vitro data supporting the evaluation of RNA-transfected mature DC in vaccination protocols as a means to overcome several obstacles to generating anti-tumor responses in vivo.

Authors
Liao, X; Li, Y; Bonini, C; Nair, S; Gilboa, E; Greenberg, PD; Yee, C
MLA Citation
Liao, X, Li, Y, Bonini, C, Nair, S, Gilboa, E, Greenberg, PD, and Yee, C. "Transfection of RNA encoding tumor antigens following maturation of dendritic cells leads to prolonged presentation of antigen and the generation of high-affinity tumor-reactive cytotoxic T lymphocytes." Mol Ther 9.5 (May 2004): 757-764.
PMID
15120337
Source
pubmed
Published In
Molecular Therapy
Volume
9
Issue
5
Publish Date
2004
Start Page
757
End Page
764
DOI
10.1016/j.ymthe.2004.02.011

A central role of RNA in developing therapeutic vaccines for cancer and infectious diseases

Authors
Gilboa, E; Santulli-Marotto, S; Nair, SK; Boczkowski, D; Zhao, YB
MLA Citation
Gilboa, E, Santulli-Marotto, S, Nair, SK, Boczkowski, D, and Zhao, YB. "A central role of RNA in developing therapeutic vaccines for cancer and infectious diseases." May 2004.
Source
wos-lite
Published In
Molecular Therapy
Volume
9
Publish Date
2004
Start Page
S222
End Page
S222

Inhibition of invariant chain expression in dendritic cells presenting endogenous antigens stimulates CD4+ T-cell responses and tumor immunity.

Induction of potent and sustained antiviral or antitumor immunity is dependent on the efficient activation of CD8+ and CD4+ T cells. While dendritic cells constitute a powerful platform for stimulating cellular immunity, presentation of endogenous antigens by dendritic cells transfected with nucleic acid-encoded antigens favors the stimulation of CD8+ T cells over that of CD4+ T cells. A short incubation of mRNA-transfected dendritic cells with antisense oligonucleotides directed against the invariant chain enhances the presentation of mRNA-encoded class II epitopes and activation of CD4+ T-cell responses in vitro and in vivo. Immunization of mice with the antisense oligonucleotide-treated dendritic cells stimulates a more potent and longer lasting CD8+ cytotoxic T-cell (CTL) response and enhances the antitumor efficacy of dendritic cell-based tumor vaccination protocols. Transient inhibition of invariant chain expression represents a simple and general method to enhance the stimulation of CD4+ T-cell responses from endogenous antigens.

Authors
Zhao, Y; Boczkowski, D; Nair, SK; Gilboa, E
MLA Citation
Zhao, Y, Boczkowski, D, Nair, SK, and Gilboa, E. "Inhibition of invariant chain expression in dendritic cells presenting endogenous antigens stimulates CD4+ T-cell responses and tumor immunity." Blood 102.12 (December 1, 2003): 4137-4142.
PMID
12920018
Source
pubmed
Published In
Blood
Volume
102
Issue
12
Publish Date
2003
Start Page
4137
End Page
4142
DOI
10.1182/blood-2003-06-1867

Injection of immature dendritic cells into adjuvant-treated skin obviates the need for ex vivo maturation.

A key and limiting step in the process of generating human monocyte-derived dendritic cells (DC) for clinical applications is maturation. In the setting of immunotherapy, DC are matured ex vivo by culturing them with various agents that mimic the conditions encountered at a site of inflammation. This study examined whether the ex vivo DC maturation step could be replaced by maturing DC in situ by injecting immature DC into sites pre-exposed to agents that induce a microenvironment conducive to in situ maturation of the injected DC. The hypothesis was that recapitulation of the physiological conditions occurring during pathogen infection would lead to optimal conditions for DC maturation, migration, and function. Murine immature DC injected into adjuvant (Adjuprime, poly-arginine, or Imiquimod)-pretreated skin exhibited lymph node migratory capacity comparable to and immunostimulatory capacity equal to or exceeding that of ex vivo matured DC. Acquisition of migratory capacity did not always correlate with enhanced immunostimulatory capacity. Immunostimulatory capacity was not enhanced when mature DC were injected into adjuvant-pretreated sites and remained below that seen with immature DC matured in situ. Immature DC injected into adjuvant-pretreated sites were more effective than mature DC in stimulating antitumor immunity in mice. (111)Indium-labeled human monocyte-derived immature DC injected into adjuvant (Imiquimod)-pretreated sites in cancer patients acquired lymph node migratory capacity comparable to ex vivo matured DC. This study shows that in situ maturation offers a simpler and potentially superior method to generate potent immunostimulatory DC for clinical immunotherapy.

Authors
Nair, S; McLaughlin, C; Weizer, A; Su, Z; Boczkowski, D; Dannull, J; Vieweg, J; Gilboa, E
MLA Citation
Nair, S, McLaughlin, C, Weizer, A, Su, Z, Boczkowski, D, Dannull, J, Vieweg, J, and Gilboa, E. "Injection of immature dendritic cells into adjuvant-treated skin obviates the need for ex vivo maturation." J Immunol 171.11 (December 1, 2003): 6275-6282.
PMID
14634145
Source
pubmed
Published In
Journal of immunology (Baltimore, Md. : 1950)
Volume
171
Issue
11
Publish Date
2003
Start Page
6275
End Page
6282

Multivalent RNA aptamers that inhibit CTLA-4 and enhance tumor immunity.

The potency of cancer immunotherapy can be enhanced by administration of high-avidity ligands specific to receptors expressed on T cells. Antibodies or cytokines are the main agents used in such capacity. Antibody-mediated inhibition of cytotoxic T cell antigen-4 (CTLA-4) function in mice augments antitumor immunity and could serve as an important adjunct in cancer immunotherapy. However, antibody-based therapy used in the setting of chronic diseases such as cancer poses significant cost, manufacturing, and regulatory challenges. Here we describe the development of RNA aptamers that bind CTLA-4 with high affinity and specificity. These aptamers inhibit CTLA-4 function in vitro and enhance tumor immunity in mice. Moreover, assembly of the aptamers into tetrameric forms significantly enhances their bioactivity in vitro and in vivo. These results demonstrate that aptamers can be used to manipulate the immune system for therapeutic applications and that multivalent versions of aptamers may be particularly potent agents in vivo.

Authors
Santulli-Marotto, S; Nair, SK; Rusconi, C; Sullenger, B; Gilboa, E
MLA Citation
Santulli-Marotto, S, Nair, SK, Rusconi, C, Sullenger, B, and Gilboa, E. "Multivalent RNA aptamers that inhibit CTLA-4 and enhance tumor immunity." Cancer Res 63.21 (November 1, 2003): 7483-7489.
PMID
14612549
Source
pubmed
Published In
Cancer Research
Volume
63
Issue
21
Publish Date
2003
Start Page
7483
End Page
7489

Synergy between tumor immunotherapy and antiangiogenic therapy.

This study tested the hypothesis that combination of antiangiogenic therapy and tumor immunotherapy of cancer is synergistic. To inhibit angiogenesis, mice were immunized with dendritic cells (DCs) transfected with mRNA that encode products that are preferentially expressed during neoangiogenesis: vascular endothelial growth factor receptor-2 (VEGFR-2) and Tie2 expressed in proliferating endothelial cells, and vascular endothelial growth factor (VEGF) expressed in the angiogenic stroma as well as the tumor cells used in this study. Immunization of mice against VEGF or VEGFR-2 stimulated cytotoxic T lymphocyte (CTL) responses and led to partial inhibition of angiogenesis. Antiangiogenic immunity was not associated with morbidity or mortality except for a transient impact on fertility seen in mice immunized against VEGFR-2, but not VEGF. Tumor growth was significantly inhibited in mice immunized against VEGF, VEGFR-2, and Tie2, either before tumor challenge or in the setting of pre-existing disease in murine B16/F10.9 melanoma and MBT-2 bladder tumor models. Coimmunization of mice against VEGFR-2 or Tie2 and total tumor RNA exhibited a synergistic antitumor effect. Synergism was also observed when mice were coimmunized with various combinations of defined tumor-expressed antigens, telomerase reverse transcriptase (TERT) or TRP-2, and VEGF or VEGFR-2. This study shows that coimmunizing mice against angiogenesis-associated and tumor-expressed antigens can deliver 2 compatible and synergistic cancer treatment modalities via a common treatment, namely immunization.

Authors
Nair, S; Boczkowski, D; Moeller, B; Dewhirst, M; Vieweg, J; Gilboa, E
MLA Citation
Nair, S, Boczkowski, D, Moeller, B, Dewhirst, M, Vieweg, J, and Gilboa, E. "Synergy between tumor immunotherapy and antiangiogenic therapy." Blood 102.3 (August 1, 2003): 964-971.
PMID
12689940
Source
pubmed
Published In
Blood
Volume
102
Issue
3
Publish Date
2003
Start Page
964
End Page
971
DOI
10.1182/blood-2002-12-3738

Immunotherapy with autologous, human dendritic cells transfected with carcinoembryonic antigen mRNA.

Immunizations with dendritic cells (DC) transfected with RNA encoding tumor antigens induce potent tumor antigen-specific immune responses in vitro and in murine models. We performed a phase I study of patients with advanced carcinoembryonic antigen (CEA)-expressing malignancies followed by a phase II study of patients with resected hepatic metastases of colon cancer to assess safety and feasibility of administering autologous DC loaded with CEA mRNA. The immunizations were well tolerated. Of the 24 evaluable patients in the dose-escalation phase, there was 1 complete response (by tumor marker), 2 minor responses, 3 with stable disease, and 18 with progressive disease. In the phase II study, 9 of 13 patients have relapsed at a median of 122 days. Evidence of an immunologic response was demonstrated in biopsies of DC injection sites and peripheral blood of selected patients. We conclude that it is feasible and safe to administer mRNA-loaded DC to patients with advanced malignancies.

Authors
Morse, MA; Nair, SK; Mosca, PJ; Hobeika, AC; Clay, TM; Deng, Y; Boczkowski, D; Proia, A; Neidzwiecki, D; Clavien, P-A; Hurwitz, HI; Schlom, J; Gilboa, E; Lyerly, HK
MLA Citation
Morse, MA, Nair, SK, Mosca, PJ, Hobeika, AC, Clay, TM, Deng, Y, Boczkowski, D, Proia, A, Neidzwiecki, D, Clavien, P-A, Hurwitz, HI, Schlom, J, Gilboa, E, and Lyerly, HK. "Immunotherapy with autologous, human dendritic cells transfected with carcinoembryonic antigen mRNA." Cancer Invest 21.3 (June 2003): 341-349.
PMID
12901279
Source
pubmed
Published In
Cancer Investigation (Informa)
Volume
21
Issue
3
Publish Date
2003
Start Page
341
End Page
349

Induction of tumor-specific cytotoxic T lymphocytes in cancer patients by autologous tumor RNA-transfected dendritic cells.

OBJECTIVE: To demonstrate the feasibility of inducing tumor antigen-specific immune responses in patients with metastatic cancer using total tumor RNA-loaded dendritic cells (DCs). SUMMARY BACKGROUND DATA: The authors have shown that DCs transfected with mRNA encoding defined tumor antigens induce tumor antigen-specific T-cell responses in vitro and in vivo. There may be significant advantages to inducing immune responses against the entire repertoire of antigens expressed by a patient's autologous tumor. METHODS: RNA was extracted from a metastatic colon cancer and used to load autologous DCs. The DCs were coincubated with autologous T cells and the cytolytic activity of the T cells was assessed by the ability to lyse the autologous tumor cells. RNA was then extracted from a metastatic lung cancer and used to load autologous DCs, followed by four injections of the DC vaccine given every 4 weeks. Tumor antigen-specific cytotoxic T lymphocyte activity was then evaluated by testing peripheral blood mononuclear cells for their ability to lyse an antigen-expressing target. RESULTS: DCs transfected with the total RNA content of autologous tumor cells stimulated antigen-specific T-cell responses that are capable of recognizing and lysing autologous, primary tumor cells in vitro. Tumor-specific immune responses were induced in a patient with a carcinoembryonic antigen-expressing adenocarcinoma after immunization with autologous DCs transfected with total tumor RNA. CONCLUSIONS: DCs transfected with total tumor RNA may represent a method for inducing immune responses against the entire repertoire of tumor antigens of surgically resected malignancies.

Authors
Nair, SK; Morse, M; Boczkowski, D; Cumming, RI; Vasovic, L; Gilboa, E; Lyerly, HK
MLA Citation
Nair, SK, Morse, M, Boczkowski, D, Cumming, RI, Vasovic, L, Gilboa, E, and Lyerly, HK. "Induction of tumor-specific cytotoxic T lymphocytes in cancer patients by autologous tumor RNA-transfected dendritic cells." Ann Surg 235.4 (April 2002): 540-549.
PMID
11923611
Source
pubmed
Published In
Annals of Surgery
Volume
235
Issue
4
Publish Date
2002
Start Page
540
End Page
549

Influence of CD4 T cells and the source of major histocompatibility complex class II-restricted peptides on cytotoxic T-cell priming by dendritic cells.

We have previously reported that bone marrow derived dendritic cells (DC) pulsed with major histocompatibility complex (MHC) class I-restricted peptide efficiently prime a cytotoxic T lymphocyte (CTL) response in vivo. Here we assess the involvement of CD4(+) T cells in the induction of CD8(+) CTL by DC by testing the ability of class II-deficient (C2D) DC, class II mutant (Alpha beta mut) DC and autologous serum generated DC (AS DC) to present class I-restricted antigens in vitro and in vivo. DC generated from the bone marrow of class II knockout mice and transgenic mice expressing a mutant class II that can not bind CD4 were phenotypically similar to wild type (wt) DC, except with regard to MHC class II expression. The C2D and Alpha beta mut DC, though fully capable of presenting the class I-restricted ovalbumin (OVA) peptide to a T-cell hybridoma in vitro, failed to prime a CTL response in vivo. Restoration of class II expression on C2D DC allowed priming of a CTL response; thus, the defect in CTL priming was indeed caused by the absence of class II expression. Likewise, DC generated in autologous serum were unable to prime a CTL response as these DC only express 'self' class II epitopes and therefore would not activate syngeneic CD4(+) T cells. Addition of exogenous class II epitopes rescued the ability of AS DC to prime a CTL response. These observations provide convincing evidence that efficient CTL induction by DC in vivo requires concomitant presentation of class II epitopes for CD4(+) T-cell induction.

Authors
Faiola, B; Doyle, C; Gilboa, E; Nair, S
MLA Citation
Faiola, B, Doyle, C, Gilboa, E, and Nair, S. "Influence of CD4 T cells and the source of major histocompatibility complex class II-restricted peptides on cytotoxic T-cell priming by dendritic cells." Immunology 105.1 (January 2002): 47-55.
PMID
11849314
Source
pubmed
Published In
Immunology
Volume
105
Issue
1
Publish Date
2002
Start Page
47
End Page
55

The feasibility and safety of immunotherapy with dendritic cells loaded with CEA mRNA following neoadjuvant chemoradiotherapy and resection of pancreatic cancer.

BACKGROUND: Resected pancreatic cancer has a high risk of recurrence and mortality despite the the use of chemoradiotherapy. Because pancreatic cancers express tumor antigens such as carcinoembryonic antigen (CEA), it may be possible to immunize patients to induce tumor antigen-specific immune responses. We hypothesize that high-frequency tumor antigen-specific immune responses will reduce recurrence and increase survival. Autologous dendritic cells (DCs) loaded with tumor antigens are particularly potent at inducing tumor antigen-specific immune responses. METHODS: Three patients with resected pancreatic adenocarcinoma following neoadjuvant chemoradiotherapy received autologous, monocyte-derived DCs loaded with the mRNA encoding CEA monthly for 6 mo. RESULTS: It was feasible to generate an adequate number of DC from these patients and to cryopreserve them for repeated use. The DC demonstrated the typical immature phenotype. The immunizations were well-tolerated without evidence of adverse events. All three developed injection site reactivity. All three are alive without evidence of disease at more than 2 1/2 yr from the original diagnosis. CONCLUSION: The postoperative period following neoadjuvant chemoradiotherapy and pancreaticoduodenectomy for pancreatic cancer is an ideal environment to test novel immune-based therapies. DC-based immunotherapy in this setting is safe and feasible and may lead to prolonged survival.

Authors
Morse, MA; Nair, SK; Boczkowski, D; Tyler, D; Hurwitz, HI; Proia, A; Clay, TM; Schlom, J; Gilboa, E; Lyerly, HK
MLA Citation
Morse, MA, Nair, SK, Boczkowski, D, Tyler, D, Hurwitz, HI, Proia, A, Clay, TM, Schlom, J, Gilboa, E, and Lyerly, HK. "The feasibility and safety of immunotherapy with dendritic cells loaded with CEA mRNA following neoadjuvant chemoradiotherapy and resection of pancreatic cancer." Int J Gastrointest Cancer 32.1 (2002): 1-6.
PMID
12630764
Source
pubmed
Published In
International Journal of Gastrointestinal Cancer
Volume
32
Issue
1
Publish Date
2002
Start Page
1
End Page
6
DOI
10.1385/IJGC:32:1:1

RNA-transfected dendritic cells

Based on their unique ability to stimulate primary immune responses, dendritic cells are the most potent antigen-presenting cells known. This ability stems from the fact that they are very efficient at the uptake and processing of antigen and they express high levels of major histocompatibility complex class I and class II, as well as costimulatory molecules, which are required to prime naive cytotoxic T-cells. Many groups of investigators have tried to take advantage of these features by developing dendritic cell-based vaccines against tumors and infectious diseases. While the basic principle in these studies is the same - dendritic cells pulsed with antigen are used to elicit cytotoxic T-cell responses - the methods used are varied. This is particularly true with respect to the nature of the antigen used and the method of antigen delivery. In this article, we will focus on the use of RNA as a form of antigen with which to load dendritic cells. We will discuss the rationale behind using RNA as an antigen source and will review recent studies in both murine and human settings that use RNA-pulsed dendritic cells as vaccines.

Authors
Nair, S; Boczkowski, D
MLA Citation
Nair, S, and Boczkowski, D. "RNA-transfected dendritic cells." Expert Review of Vaccines 1.4 (2002): 507-513.
PMID
12901589
Source
scival
Published In
Expert Review of Vaccines
Volume
1
Issue
4
Publish Date
2002
Start Page
507
End Page
513
DOI
10.1586/14760584.1.4.507

Erratum: Influence of CD4 T cells and the source of major histocompatibility complex class II-restricted peptides on cytotoxic T-cell priming by dendritic cells (Immunology (2002) 105 (47-55))

Authors
Faiola, B; Doyle, C; Gilboa, E; Nair, S
MLA Citation
Faiola, B, Doyle, C, Gilboa, E, and Nair, S. "Erratum: Influence of CD4 T cells and the source of major histocompatibility complex class II-restricted peptides on cytotoxic T-cell priming by dendritic cells (Immunology (2002) 105 (47-55))." Immunology 106.1 (2002): 122-123.
Source
scival
Published In
Immunology
Volume
106
Issue
1
Publish Date
2002
Start Page
122
End Page
123
DOI
10.1046/j.1365-2567.2002.01439.x

Isolation and generation of human dendritic cells.

Dendritic cells are highly specialized antigen-presenting cells (APC), which may be isolated or generated from human blood mononuclear cells. Although mature blood dendritic cells normally represent 0.2% of human blood mononuclear cells, their frequency can be greatly increased using the cell enrichment methods described in this unit. More highly purified dendritic cell preparations can be obtained from these populations by sorting of fluorescence-labeled cells. Alternatively, dendritic cells can be generated from monocytes by culture with the appropriate cytokines, as described here. In addition, a negative selection approach is provided that may be employed to generate cell preparations that have been depleted of dendritic cells to be used for comparison in functional studies.

Authors
Tedder, TF; Jansen, PJ
MLA Citation
Tedder, TF, and Jansen, PJ. "Isolation and generation of human dendritic cells." Curr Protoc Immunol Chapter 7 (May 2001): Unit-7.32.
PMID
18432844
Source
pubmed
Published In
Current Protocols in Immunology
Volume
Chapter 7
Publish Date
2001
Start Page
Unit
End Page
7.32
DOI
10.1002/0471142735.im0732s23

Induction of polyclonal prostate cancer-specific CTL using dendritic cells transfected with amplified tumor RNA.

Polyvalent cancer vaccines targeting the entire antigenic spectrum on tumor cells may represent a superior therapeutic strategy for cancer patients than vaccines solely directed against single Ags. In this study, we show that autologous dendritic cells (DC) transfected with RNA amplified from microdissected tumor cells are capable of stimulating CTL against a broad set of unidentified and critical prostate-specific Ags. Although the polyclonal CTL responses generated with amplified tumor RNA-transfected DC encompassed as a subcomponent a response against prostate-specific Ag (PSA) as well as against telomerase reverse transcriptase, the tumor-specific CTL were consistently more effective than PSA or telomerase reverse transcriptase CTL to lyse tumor targets, suggesting the superiority of the polyclonal response. Although tumor RNA-transfected DC stimulated CTL, which recognized not only tumor but also self-Ags expressed by benign prostate tissue, these cross-reactive CTL were exclusively specific for the PSA, indicating an immunodominant role of PSA in the prostate cancer-specific immune response. Our data suggest that tumor RNA-transfected DC may represent a broadly applicable, potentially clinically effective vaccine strategy for prostate cancer patients, which is not limited by tumor tissue availability for Ag preparation and may minimize the risk of clonal tumor escape.

Authors
Heiser, A; Maurice, MA; Yancey, DR; Wu, NZ; Dahm, P; Pruitt, SK; Boczkowski, D; Nair, SK; Ballo, MS; Gilboa, E; Vieweg, J
MLA Citation
Heiser, A, Maurice, MA, Yancey, DR, Wu, NZ, Dahm, P, Pruitt, SK, Boczkowski, D, Nair, SK, Ballo, MS, Gilboa, E, and Vieweg, J. "Induction of polyclonal prostate cancer-specific CTL using dendritic cells transfected with amplified tumor RNA." J Immunol 166.5 (March 1, 2001): 2953-2960.
PMID
11207244
Source
pubmed
Published In
Journal of immunology (Baltimore, Md. : 1950)
Volume
166
Issue
5
Publish Date
2001
Start Page
2953
End Page
2960

Preoperative mobilization of circulating dendritic cells by Flt3 ligand administration to patients with metastatic colon cancer.

PURPOSE: To evaluate preoperative dendritic cell (DC) mobilization and tumor infiltration after administration of Flt3 ligand (Flt3L) to patients with metastatic colon cancer. PATIENTS AND METHODS: Twelve patients with colon cancer metastatic to the liver or lung received Flt3L (20 microg/kg/d subcutaneously for 14 days for one to three cycles at monthly intervals) before attempted metastasectomy. The number and phenotype of DCs mobilized into peripheral-blood mononuclear cells (PBMCs) were evaluated by flow cytometry. After surgical resection, metastatic tumor tissue was evaluated for DC infiltration. In vivo immune responses to recall antigens were measured. RESULTS: After Flt3L administration, on average, the total number of leukocytes in the peripheral blood increased from 5.9 +/- 1.0 x 10(3)/mm(3) to 11.2 +/- 3.8 x 10(3)/mm(3) (mean +/- SD, P: =. 0001). The percentage of CD11c(+)CD14(-) DCs in PBMCs increased from 2.4% +/- 1.8% to 8.8% +/- 4.7% (P: =.004). Delayed-type hypersensitivity (DTH) responses to recall antigens (CANDIDA:, mumps, and tetanus) showed marginally significant increases in reactivity after Flt3L administration (P: =.06, P: =.03, and P: =.08, respectively). An increase in the number of DCs was observed at the periphery of the tumors of patients who received Flt3L compared with those of patients who had not. CONCLUSION: Flt3L is capable of mobilizing DCs into the peripheral blood of patients with metastatic colon cancer and may be associated with increases in DC infiltration in the peritumoral regions. Flt3L mobilization is associated with a trend toward increased DTH responses to recall antigens in vivo. The use of Flt3L to increase circulating DCs for cancer immunotherapy should be considered.

Authors
Morse, MA; Nair, S; Fernandez-Casal, M; Deng, Y; St Peter, M; Williams, R; Hobeika, A; Mosca, P; Clay, T; Cumming, RI; Fisher, E; Clavien, P; Proia, AD; Niedzwiecki, D; Caron, D; Lyerly, HK
MLA Citation
Morse, MA, Nair, S, Fernandez-Casal, M, Deng, Y, St Peter, M, Williams, R, Hobeika, A, Mosca, P, Clay, T, Cumming, RI, Fisher, E, Clavien, P, Proia, AD, Niedzwiecki, D, Caron, D, and Lyerly, HK. "Preoperative mobilization of circulating dendritic cells by Flt3 ligand administration to patients with metastatic colon cancer." J Clin Oncol 18.23 (December 1, 2000): 3883-3893.
PMID
11099317
Source
pubmed
Published In
Journal of Clinical Oncology
Volume
18
Issue
23
Publish Date
2000
Start Page
3883
End Page
3893
DOI
10.1200/JCO.2000.18.23.3883

Multiple signals are required for IL-12 production by Flt-3 ligand mobilized dendritic cells.

Authors
Mosca, PJ; Hobeika, AC; Clay, TM; Nair, SK; Thomas, EK; Caron, DA; Lyerly, HK; Morse, MA
MLA Citation
Mosca, PJ, Hobeika, AC, Clay, TM, Nair, SK, Thomas, EK, Caron, DA, Lyerly, HK, and Morse, MA. "Multiple signals are required for IL-12 production by Flt-3 ligand mobilized dendritic cells." November 16, 2000.
Source
wos-lite
Published In
Blood
Volume
96
Issue
11
Publish Date
2000
Start Page
295A
End Page
295A

A subset of human monocyte-derived dendritic cells expresses high levels of interleukin-12 in response to combined CD40 ligand and interferon-gamma treatment.

Dendritic cells (DCs) may arise from multiple lineages and progress through a series of intermediate stages until fully mature, at which time they are capable of optimal antigen presentation and T-cell activation. High cell surface expression of CD83 is presumed to correlate with full maturation of DCs, and a number of agents have been shown to increase CD83 expression on DCs. We hypothesized that interleukin 12 (IL-12) expression would be a more accurate marker of functionally mature DCs capable of activating antigen-specific T cells. We used combinations of signaling through CD40, using CD40 ligand trimer (CD40L), and interferon gamma to demonstrate that CD83 expression is necessary but not sufficient for optimal production of IL-12 by DCs. Phenotypically mature DCs could be induced to produce high levels of IL-12 p70 only when provided 2 simultaneous stimulatory signals. By intracellular cytokine detection, we determined that only a subset of cells that express high levels of CD80 and CD83 generate large amounts of IL-12. DCs matured with both signals are superior to DCs stimulated with the individual agents in activating antigen-specific T cell in vitro. These findings have important implications regarding the identification, characterization, and clinical application of functionally mature DCs.

Authors
Mosca, PJ; Hobeika, AC; Clay, TM; Nair, SK; Thomas, EK; Morse, MA; Lyerly, HK
MLA Citation
Mosca, PJ, Hobeika, AC, Clay, TM, Nair, SK, Thomas, EK, Morse, MA, and Lyerly, HK. "A subset of human monocyte-derived dendritic cells expresses high levels of interleukin-12 in response to combined CD40 ligand and interferon-gamma treatment." Blood 96.10 (November 15, 2000): 3499-3504.
PMID
11071647
Source
pubmed
Published In
Blood
Volume
96
Issue
10
Publish Date
2000
Start Page
3499
End Page
3504

RNA-transfected dendritic cells in cancer immunotherapy.

Authors
Mitchell, DA; Nair, SK
MLA Citation
Mitchell, DA, and Nair, SK. "RNA-transfected dendritic cells in cancer immunotherapy." J Clin Invest 106.9 (November 2000): 1065-1069. (Review)
PMID
11067858
Source
pubmed
Published In
Journal of Clinical Investigation
Volume
106
Issue
9
Publish Date
2000
Start Page
1065
End Page
1069
DOI
10.1172/JCI11405

Induction of cytotoxic T cell responses and tumor immunity against unrelated tumors using telomerase reverse transcriptase RNA transfected dendritic cells.

The polypeptide component of telomerase (TERT) is an attractive candidate for a broadly expressed tumor rejection antigen because telomerase is silent in normal tissues but is reactivated in more than 85% of cancers. Here we show that immunization against TERT induces immunity against tumors of unrelated origin. Immunization of mice with TERT RNA-transfected dendritic cells (DC) stimulated cytotoxic T lymphocytes (CTL), which lysed melanoma and thymoma tumor cells and inhibited the growth of three unrelated tumors in mice of distinct genetic backgrounds. TERT RNA-transfected human DC stimulated TERT-specific CTL in vitro that lysed human tumor cells, including Epstein Barr virus (EBV)-transformed B cells as well as autologous tumor targets from patients with renal and prostate cancer. Tumor RNA-transfected DC were used as surrogate targets in the CTL assays, obviating the difficulties in obtaining tumor cells from cancer patients. In one instance, where a tumor cell line was successfully established in culture from a patient with renal cancer, the patient's tumor cells were efficiently lysed by the CTL. Immunization with tumor RNA was generally more effective than immunization with TERT RNA, suggesting that an optimal immunization protocol may have to include TERT as well as additional tumor antigens.

Authors
Nair, SK; Heiser, A; Boczkowski, D; Majumdar, A; Naoe, M; Lebkowski, JS; Vieweg, J; Gilboa, E
MLA Citation
Nair, SK, Heiser, A, Boczkowski, D, Majumdar, A, Naoe, M, Lebkowski, JS, Vieweg, J, and Gilboa, E. "Induction of cytotoxic T cell responses and tumor immunity against unrelated tumors using telomerase reverse transcriptase RNA transfected dendritic cells." Nat Med 6.9 (September 2000): 1011-1017.
PMID
10973321
Source
pubmed
Published In
Nature Medicine
Volume
6
Issue
9
Publish Date
2000
Start Page
1011
End Page
1017
DOI
10.1038/79519

Cancer immunotherapy with tumor RNA-transfected dendritic cells

Authors
Gilboa, E; Nair, SK; Boczkowski, D
MLA Citation
Gilboa, E, Nair, SK, and Boczkowski, D. "Cancer immunotherapy with tumor RNA-transfected dendritic cells." August 2000.
Source
wos-lite
Published In
Cancer Gene Therapy
Volume
7
Issue
8
Publish Date
2000
Start Page
1203
End Page
1203

Induction of cytotoxic T lymphocytes with dendritic cells transfected with human papillomavirus E6 and E7 RNA: implications for cervical cancer immunotherapy.

Human papillomavirus (HPV) infection is associated with cervical cancer. The high-risk HPV E6 and E7 oncoproteins are constitutively expressed in most cervical carcinoma cells, and are, therefore, attractive antigens for cytotoxic T-lymphocyte (CTL)-mediated immunotherapy. The objective of this study was to evaluate the use of dendritic cells (DCs) transfected with RNA encoding the E6 and E7 protein for cervical cancer immunotherapy. The authors have shown that DCs transfected with RNA-encoding antigen stimulate potent antigen-specific CTL responses in vitro and in vivo. In this study, they tried to determine whether DCs transfected with E6 and E7 RNA stimulate primary, antigen-specific CTL responses in vitro. The results show that DCs pulsed with E6 or E7 RNA stimulate antigen-specific CTL responses that recognize and lyse DCs transfected with E6 and E7 RNA and human cervical carcinoma cells expressing the E6 and E7 products, and the lysis was comparable to that achieved with E6 and E7 peptide-pulsed DCs. Dendritic cells cotransfected with both E6 and E7 RNA stimulate CTLs that are more effective at lysing human cervical cancer cells. This study provides a rationale for the development of cervical carcinoma immunotherapy using DCs transfected with HPV E6 and E7 RNA.

Authors
Thornburg, C; Boczkowski, D; Gilboa, E; Nair, SK
MLA Citation
Thornburg, C, Boczkowski, D, Gilboa, E, and Nair, SK. "Induction of cytotoxic T lymphocytes with dendritic cells transfected with human papillomavirus E6 and E7 RNA: implications for cervical cancer immunotherapy." J Immunother 23.4 (July 2000): 412-418.
PMID
10916750
Source
pubmed
Published In
Journal of Immunotherapy
Volume
23
Issue
4
Publish Date
2000
Start Page
412
End Page
418

Human dendritic cells transfected with RNA encoding prostate-specific antigen stimulate prostate-specific CTL responses in vitro.

Although immunological tolerance to self Ags represents an important mechanism to prevent normal tissue injury, there is growing evidence that tolerance to tumor Ags, which often represent normal peripherally expressed proteins, is not absolute and can be effectively reverted. Prostate-specific Ag (PSA) is a self Ag expressed by both normal and malignant prostatic epithelium, and therefore offers a unique opportunity to examine the ability of self Ags to serve as specific CTL targets. In this study, we investigated the efficacy of autologous dendritic cells (DC) transfected with mRNA encoding PSA to stimulate CTL against PSA Ags in vitro. Ag in form of RNA carries the advantage to encode multiple epitopes for many HLA alleles, thus permitting induction of CTL responses among many cancer patients independent of their HLA repertoire. In this study, we show that PSA mRNA-transfected DC were capable of stimulating primary CTL responses against PSA Ags in vitro. The PSA-specific CTL did not cross-react with kallikrein Ags, a protein, which shares significant homology with PSA, suggesting that harmful autoimmune toxicity may not represent a significant problem with this approach. PSA RNA-transfected DC generated from male or female healthy volunteers or from cancer patients were equally effective in stimulating PSA-specific CTL in vitro, implying that neither natural tolerance to PSA Ags nor tumor-mediated T cell anergy may represent major barriers for CTL generation against the self Ag PSA. This study provides a preclinical rationale for using PSA RNA-transfected DC in active or adoptive immunization protocols.

Authors
Heiser, A; Dahm, P; Yancey, DR; Maurice, MA; Boczkowski, D; Nair, SK; Gilboa, E; Vieweg, J
MLA Citation
Heiser, A, Dahm, P, Yancey, DR, Maurice, MA, Boczkowski, D, Nair, SK, Gilboa, E, and Vieweg, J. "Human dendritic cells transfected with RNA encoding prostate-specific antigen stimulate prostate-specific CTL responses in vitro." J Immunol 164.10 (May 15, 2000): 5508-5514.
PMID
10799919
Source
pubmed
Published In
Journal of immunology (Baltimore, Md. : 1950)
Volume
164
Issue
10
Publish Date
2000
Start Page
5508
End Page
5514

RNA transfected dendritic cells as cancer vaccines.

Immunization with dendritic cells loaded with tumor antigens could represent a powerful method of inducing antitumor immunity. Studies from several laboratories have shown that immunization with dendritic cells pulsed with specific antigens prime cytotoxic T-cells and engender tumor immunity. This review will focus on the use of dendritic cells transfected with RNA as cancer vaccines, with emphasis on the potential advantages of using RNA. The majority of cancer patients who lack an identified tumor antigen and/or cannot provide sufficient tumor tissue for antigen preparation will be excluded from treatment with cancer vaccines based on using either specific tumor antigens or mixtures of tumor-derived antigens in the form of peptides or proteins isolated from tumor cells. Vaccination with the mRNA content of tumor cells would extend the scope of vaccination to this group of patients as well because RNA can be amplified from very few cancer cells.

Authors
Mitchell, DA; Nair, SK
MLA Citation
Mitchell, DA, and Nair, SK. "RNA transfected dendritic cells as cancer vaccines." Curr Opin Mol Ther 2.2 (April 2000): 176-181. (Review)
PMID
11249639
Source
pubmed
Published In
Current Opinion in Molecular Therapeutics
Volume
2
Issue
2
Publish Date
2000
Start Page
176
End Page
181

Induction of tumor immunity and cytotoxic T lymphocyte responses using dendritic cells transfected with messenger RNA amplified from tumor cells.

Unique patient-specific tumor antigens may constitute the dominant antigens in the antitumor immune response. Hence, vaccination with the patient's own repertoire of tumor antigens may offer a superior strategy to elicit protective immunity. We have shown previously that dendritic cells transfected with mRNA isolated from tumor cells stimulate potent CTL responses and engender protective immunity in tumor-bearing mice. In the current study, we demonstrate that tumor mRNA, isolated from murine tumor cell lines or from primary human tumor cells microdissected from frozen tissue sections, can be amplified without loss of function. This study provides the foundations for an effective and broadly applicable treatment that does not require the characterization of the relevant antigenic profile in each patient and will not be limited by tumor tissue availability for antigen preparation.

Authors
Boczkowski, D; Nair, SK; Nam, JH; Lyerly, HK; Gilboa, E
MLA Citation
Boczkowski, D, Nair, SK, Nam, JH, Lyerly, HK, and Gilboa, E. "Induction of tumor immunity and cytotoxic T lymphocyte responses using dendritic cells transfected with messenger RNA amplified from tumor cells." Cancer Res 60.4 (February 15, 2000): 1028-1034.
PMID
10706120
Source
pubmed
Published In
Cancer Research
Volume
60
Issue
4
Publish Date
2000
Start Page
1028
End Page
1034

Phenotypic and functional maturation of dendritic cells mediated by heparan sulfate

Primary immune responses are thought to be induced by dendritic cells. To promote such responses, dendritic cells must be activated by exogenous agonists, such as LPS, or by products of activated leukocytes, such as TNF-α and IL-1. How dendritic cells might be activated in the absence of exogenous stimuli, or without the immediate presence of activated leukocytes, as might occur in immunity to tumor cells or transplants, is unknown. We postulated that heparan sulfate, an acidic, biologically active polysaccharide associated with cell membranes and extracellular matrices, which is rapidly released under conditions of inflammation and tissue damage, might provide such a stimulus. Incubation of immature murine dendritic cells with heparan sulfate induced phenotypic maturation evidenced by up-regulation of I-A, CD40, CD54 (ICAM-1), CD80 (B7-1), and CD86 (B7-2). Dendritic cells exposed to heparan sulfate exhibited a markedly lowered rate of Ag uptake and increased allostimulatory capacity. Stimulation of dendritic cells with heparan sulfate induced release of TNF-α, IL-β, and IL-6, although the maturation of dendritic cells was independent of these cytokines. These results suggest that soluble heparan sulfate chains, as products of the degradation of heparan sulfate proteoglycan, might induce maturation of dendritic cells without exogenous stimuli, thus contributing to the generation and maintenance of primary immune responses.

Authors
Kodaira, Y; Nair, SK; Wrenshall, LE; Gilboa, E; Platt, JL
MLA Citation
Kodaira, Y, Nair, SK, Wrenshall, LE, Gilboa, E, and Platt, JL. "Phenotypic and functional maturation of dendritic cells mediated by heparan sulfate." Journal of Immunology 165.3 (2000): 1599-1604.
PMID
10903769
Source
scival
Published In
Journal of Immunology
Volume
165
Issue
3
Publish Date
2000
Start Page
1599
End Page
1604

Involvement of an ATP-dependent peptide chaperone in cross-presentation after DNA immunization

Immunization with plasmid DNA holds promise as a vaccination strategy perhaps useful in situations that currently lack vaccines, since the major means of immune induction may differ from more conventional approach. In the present study, we demonstrate that exposure of macrophages to plasmid DNA encoding viral proteins or OVA generates Ag-specific material that, when presented in vitro by dendritic cells to naive T cells, induces primary CTL response or elicits IL-2 production from an OVA peptide-specific T-T hybridoma. The immunogenic material released was proteinaceous in nature, free of apoptotic bodies, and had an apparent m.w. much larger than a 9-11-aa CTL-recognizable peptide. The macrophage-released factor(s) specifically required a hydrolyzable ATP substrate and was inhibited by procedures that removed or hydrolyzed ATP; in addition, anti-heat-shock protein 70 antiserum abrogated the activity to a large extent. These results indicate the possible involvement of a heat-shock protein 70-linked peptide chaperone in a cross- priming method of immune induction by DNA vaccination. Such a cross-priming process may represent a principal mechanism by which plasmid DNA delivered to cells such as myocytes effectively shuttle Ag to DC or other APC to achieve CTL induction in vivo.

Authors
Kumaraguru, U; Rouse, RJD; Nair, SK; Bruce, BD; Rouse, BT
MLA Citation
Kumaraguru, U, Rouse, RJD, Nair, SK, Bruce, BD, and Rouse, BT. "Involvement of an ATP-dependent peptide chaperone in cross-presentation after DNA immunization." Journal of Immunology 165.2 (2000): 750-759.
PMID
10878348
Source
scival
Published In
Journal of Immunology
Volume
165
Issue
2
Publish Date
2000
Start Page
750
End Page
759

Effectiveness of combined interleukin 2 and B7.1 vaccination strategy is dependent on the sequence and order: A liposome-mediated gene therapy treatment for bladder cancer

We have developed a novel liposome-mediated immunogene therapy using interleukin 2 (IL-2) and B7.1 in a murine bladder cancer model. A carcinogen- induced murine bladder cancer cell line, MBT-2, was transfected with cationic liposome 1,2-dimyristyloxypropyl-3-dimethyl-hydroxyethyl ammonium bromide/dioleolylphosphatidylethanolamine and IL-2 plasmid. The optimized transfection condition generated IL-2 levels of 245-305 ng/106 cells/24 h, 100-fold higher than the levels seen with retrovirus transfection. Ninety percent of the peak level of IL-2 production was maintained for up to 11 days after transfection. Animal studies were conducted in C3H/HeJ female mice with 2 x 104 MBT-2 cells implanted orthotopically on day 0. Multiple vaccination schedules were performed with i.p. injection of 5 x 106 IL-2 and/or B7.1 gene-modified cell preparations. The greatest impact on survival was observed with the day 5, 10, and 15 regimen. Control animals receiving retrovirally gene-modified MBT-2/IL-2 cell preparations had a median survival of 29 days. Animals receiving the IL-2 liposomally gene-modified cell preparation alone had a median survival of 46 days. Seventy-five percent of animals receiving IL-2 followed by B7.1 gene-modified tumor vaccines were the only group to show complete tumor-free survival at day 60. All of these surviving animals rejected the parental MBT-2 tumor rechallenge and survived at day 120 with a high CTL response. In conclusion, liposome-mediated transfection demonstrates a clear advantage as compared with the retroviral system in the MBT-2 model. Multi-agent as opposed to single-agent cytokine gene-modified tumor vaccines were beneficial. These 'targeted' sequential vaccinations using IL-2 followed by B7.1 gene-modified tumor cells significantly increased a systemic immune response that translated into increased survival.

Authors
Larchian, WA; Horiguchi, Y; Nair, SK; Fair, WR; Heston, WDW; Gilboa, E
MLA Citation
Larchian, WA, Horiguchi, Y, Nair, SK, Fair, WR, Heston, WDW, and Gilboa, E. "Effectiveness of combined interleukin 2 and B7.1 vaccination strategy is dependent on the sequence and order: A liposome-mediated gene therapy treatment for bladder cancer." Clinical Cancer Research 6.7 (2000): 2913-2920.
PMID
10914741
Source
scival
Published In
Clinical Cancer Research
Volume
6
Issue
7
Publish Date
2000
Start Page
2913
End Page
2920

Induction of carcinoembryonic antigen (CEA)-specific cytotoxic T-lymphocyte responses in vitro using autologous dendritic cells loaded with CEA peptide or CEA RNA in patients with metastatic malignancies expressing CEA.

The application of dendritic cells (DC) to the active immunotherapy of cancer currently relies on the generation of potent DC capable of presenting tumor antigens such as carcinoembryonic antigen (CEA). It is unknown whether the T cells of patients with advanced malignancies can be reliably stimulated against tumor antigens by their autologous DC. In this study, starting with the peripheral blood mononuclear cells (PBMC) of patients with metastatic malignancies expressing CEA, autologous DCs were generated in vitro in serum-free media supplemented with GM-CSF and IL-4. The DCs from HLA A2 positive patients were loaded with the CEA peptide CAP-1 and the DCs from HLA A2 negative patients were depleted of bystander lymphocytes and loaded with mRNA encoding CEA. The DC preparations were tested to determine their phenotype and were used to stimulate autologous PBMC twice, separated by 10-14 days. The stimulated cells were then tested for their ability to lyse CEA-expressing target cells. We successfully generated an adequate number of DC for a clinical trial from all patients. The harvested DC preparations contained 49% DC and 87% DC if depleted of bystander lymphocytes. Phenotypic analysis showed the typical pattern of CD11c+ CD40+ CD86+ HLA-DR+ CD80(low) CD83(low) CD14(low). All preparations but one were able to stimulate CEA-specific cytotoxic T-lymphocyte (CTL) activity, suggesting that the majority of patients are not anergic to CEA and possess functional DC. The CTL activity was similar for the CEA peptide and CEA RNA-loaded DC.

Authors
Nair, SK; Hull, S; Coleman, D; Gilboa, E; Lyerly, HK; Morse, MA
MLA Citation
Nair, SK, Hull, S, Coleman, D, Gilboa, E, Lyerly, HK, and Morse, MA. "Induction of carcinoembryonic antigen (CEA)-specific cytotoxic T-lymphocyte responses in vitro using autologous dendritic cells loaded with CEA peptide or CEA RNA in patients with metastatic malignancies expressing CEA." Int J Cancer 82.1 (July 2, 1999): 121-124.
PMID
10360830
Source
pubmed
Published In
International Journal of Cancer
Volume
82
Issue
1
Publish Date
1999
Start Page
121
End Page
124

Calreticulin displays in vivo peptide-binding activity and can elicit CTL responses against bound peptides.

Calreticulin is an endoplasmic reticulum (ER) chaperone that displays lectin activity and contributes to the folding pathways for nascent glycoproteins. Calreticulin also participates in the reactions yielding assembly of peptides onto nascent MHC class I molecules. By chemical and immunological criteria, we identify calreticulin as a peptide-binding protein and provide data indicating that calreticulin can elicit CTL responses to components of its bound peptide pool. In an adoptive immunotherapy protocol, dendritic cells pulsed with calreticulin isolated from B16/F10.9 murine melanoma, E.G7-OVA, or EL4 thymoma tumors elicited a CTL response to as yet unknown tumor-derived Ags or the known OVA Ag. To evaluate the relative efficacy of calreticulin in eliciting CTL responses, the ER chaperones GRP94/gp96, BiP, ERp72, and protein disulfide isomerase were purified in parallel from B16/F10.9, EL4, and E.G7-OVA tumors, and the capacity of the proteins to elicit CTL responses was compared. In both the B16/F10.9 and E.G7-OVA models, calreticulin was as effective as or more effective than GRP94/gp96 in eliciting CTL responses. Little to no activity was observed for BiP, ERp72, and protein disulfide isomerase. The observed antigenic activity of calreticulin was recapitulated in in vitro experiments, in which it was observed that pulsing of bone marrow dendritic cells with E.G7-OVA-derived calreticulin elicited sensitivity to lysis by OVA-specific CD8+ T cells. These data identify calreticulin as a peptide-binding protein and indicate that calreticulin-bound peptides can be re-presented on dendritic cell class I molecules for recognition by CD8+ T cells.

Authors
Nair, S; Wearsch, PA; Mitchell, DA; Wassenberg, JJ; Gilboa, E; Nicchitta, CV
MLA Citation
Nair, S, Wearsch, PA, Mitchell, DA, Wassenberg, JJ, Gilboa, E, and Nicchitta, CV. "Calreticulin displays in vivo peptide-binding activity and can elicit CTL responses against bound peptides." J Immunol 162.11 (June 1, 1999): 6426-6432.
PMID
10352256
Source
pubmed
Published In
Journal of immunology (Baltimore, Md. : 1950)
Volume
162
Issue
11
Publish Date
1999
Start Page
6426
End Page
6432

A Phase I study of active immunotherapy with carcinoembryonic antigen peptide (CAP-1)-pulsed, autologous human cultured dendritic cells in patients with metastatic malignancies expressing carcinoembryonic antigen.

Dendritic cells (DCs), antigen-presenting cells capable of priming naive T cells to specific antigens in an HLA-restricted fashion, have been demonstrated to induce protective T cell-mediated immunity in tumor-bearing animals. We performed this study to test the safety, feasibility, and clinical response of immunizations with in vitro-generated DCs, loaded with an HLA-A2-restricted peptide fragment of the tumor antigen carcinoembryonic antigen (CEA), for the treatment of patients with advanced CEA-expressing malignancies. Cell preparations enriched for autologous DCs were generated from the patients' plastic adherent peripheral blood mononuclear cells in serum-free media supplemented with granulocyte macrophage colony-stimulating factor and interleukin-4. Within the cell preparation, 66% of the cells expressed the phenotype typical for DCs (CD86high, HLA-DRhigh, and CD14low). The DCs were loaded with the CEA peptide CAP-1 and cryopreserved. Groups of three to six patients received four weekly or biweekly i.v. infusions of the CAP-1-loaded DC in escalating dose levels of 1 x 10(7), 3 x 10(7), and 1 x 10(8) cells/dose. A subset of the patients in the last group also received intradermal injections of 1 x 10(6) DCs. There were no toxicities directly referable to the treatments. One patient had a minor response, and one had stable disease. Skin punch biopsy at DC injection sites demonstrated pleomorphic infiltrates in the three patients evaluated. We conclude that it is feasible and safe to generate and administer large numbers of previously cryopreserved DCs loaded with CAP-1 peptide to patients with advanced malignancies.

Authors
Morse, MA; Deng, Y; Coleman, D; Hull, S; Kitrell-Fisher, E; Nair, S; Schlom, J; Ryback, ME; Lyerly, HK
MLA Citation
Morse, MA, Deng, Y, Coleman, D, Hull, S, Kitrell-Fisher, E, Nair, S, Schlom, J, Ryback, ME, and Lyerly, HK. "A Phase I study of active immunotherapy with carcinoembryonic antigen peptide (CAP-1)-pulsed, autologous human cultured dendritic cells in patients with metastatic malignancies expressing carcinoembryonic antigen." Clin Cancer Res 5.6 (June 1999): 1331-1338.
PMID
10389916
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
5
Issue
6
Publish Date
1999
Start Page
1331
End Page
1338

Optimization of the sequence of antigen loading and CD40-ligand-induced maturation of dendritic cells.

Dendritic cells (DCs), matured by CD40-ligand (CD40L), undergo marked changes in their ability to process and present antigen, resulting in augmented lymphocyte stimulatory activity. We demonstrate that the form of the tumor antigen (peptide or genetic material) used to load the DCs dictates the required sequence of antigen loading and maturation for antitumor immunotherapy. Optimal stimulation of carcinoembryonic antigen (CEA)-specific CTLs by peptide-loaded DCs occurs when DCs from cancer patients are matured with CD40L before exposure to CEA peptide, whereas optimal stimulation by RNA-transfected DCs occurs when the DCs are loaded with CEA RNA before maturation with CD40L.

Authors
Morse, MA; Lyerly, HK; Gilboa, E; Thomas, E; Nair, SK
MLA Citation
Morse, MA, Lyerly, HK, Gilboa, E, Thomas, E, and Nair, SK. "Optimization of the sequence of antigen loading and CD40-ligand-induced maturation of dendritic cells." Cancer Res 58.14 (July 15, 1998): 2965-2968.
PMID
9679955
Source
pubmed
Published In
Cancer Research
Volume
58
Issue
14
Publish Date
1998
Start Page
2965
End Page
2968

Dendritic cell/macrophage precursors capture exogenous antigen for MHC class I presentation by dendritic cells.

Presentation of MHC class I antigens by professional antigen-presenting cells (APC) is an important pathway in priming cytotoxic T lymphocyte responses in vivo. This study sought to identify the nature of the professional APC responsible for indirect class I presentation by examining a special feature of professional APC, namely their ability to process exogenous forms of antigen for class I presentation. Incubation of highly purified bone marrow-derived precursor cells with chicken ovalbumin (OVA) led to the efficient presentation of the major class I-restricted OVA determinant by mature dendritic cells (DC), but not by macrophages (Mphi) derived from the precursor population. DC as well as macrophages were, however, able to mediate class II presentation of OVA, suggesting that macrophages were deficient in class I processing but not in capturing exogenous OVA. The majority of mature DC, i.e. over 80 %, generated from the precursor cells pulsed with OVA, presented the class I OVA epitope. Upon maturation, class I presentation of OVA by DC was greatly reduced, suggesting that class I processing of exogenous antigen is modulated during DC maturation in a manner similar to class II antigen processing. This study shows that bone marrow-derived DC/ME progenitors capture exogenous antigen for class I presentation, and that cells of the DC lineage can be functionally distinguished from cells of the macrophage lineage based on their ability to process exogenous antigen for class I presentation.

Authors
Mitchell, DA; Nair, SK; Gilboa, E
MLA Citation
Mitchell, DA, Nair, SK, and Gilboa, E. "Dendritic cell/macrophage precursors capture exogenous antigen for MHC class I presentation by dendritic cells." Eur J Immunol 28.6 (June 1998): 1923-1933.
PMID
9645374
Source
pubmed
Published In
European Journal of Immunology
Volume
28
Issue
6
Publish Date
1998
Start Page
1923
End Page
1933
DOI
10.1002/(SICI)1521-4141(199806)28:06<1923::AID-IMMU1923>3.0.CO;2-9

Immunotherapy of cancer with dendritic-cell-based vaccines.

Animal studies have shown that vaccination with genetically modified tumor cells or with dendritic cells (DC) pulsed with tumor antigens are potent strategies to elicit protective immunity in tumor-bearing animals, more potent than "conventional" strategies that have been tested in clinical settings with limited success. While both vaccination strategies are forms of cell therapy requiring complex and costly ex vivo manipulations of the patient's cells, current protocols using dendritic cells are considerably simpler and would be more widely available. Vaccination with defined tumor antigens presented by DC has obvious appeal. However, in view of the expected emergence of antigen-loss variants as well as natural immunovariation, effective vaccine formulations must contain mixtures of commonly, if not universally, expressed tumor antigens. When, or even if, such common tumor antigens will be identified cannot be, predicted, however. Thus, for the foreseeable future, vaccination with total-tumor-derived material as source of tumor antigens may be preferable to using defined tumor antigens. Vaccination with undefined tumor-derived antigens will be limited, however, by the availability of sufficient tumor tissue for antigen preparation. Because the mRNA content of single cells can be amplified, tumor mRNA, or corresponding cDNA libraries, offer an unlimited source of tumor antigens. DC transfected with tumor RNA were shown to engender potent antitumor immunity in animal studies. Thus, immunotherapy using autologous DC loaded with unfractionated tumor-derived antigens in the form of RNA emerges as a potentially powerful and broadly useful vaccination strategy for cancer patients.

Authors
Gilboa, E; Nair, SK; Lyerly, HK
MLA Citation
Gilboa, E, Nair, SK, and Lyerly, HK. "Immunotherapy of cancer with dendritic-cell-based vaccines." Cancer Immunol Immunother 46.2 (April 1998): 82-87. (Review)
PMID
9558003
Source
pubmed
Published In
Cancer Immunology, Immunotherapy
Volume
46
Issue
2
Publish Date
1998
Start Page
82
End Page
87

Induction of primary carcinoembryonic antigen (CEA)-specific cytotoxic T lymphocytes in vitro using human dendritic cells transfected with RNA.

Dendritic cells (DC) generated from the peripheral blood mononuclear cells of healthy individuals or from cancer patients transfected with carcinoembryonic antigen (CEA) mRNA stimulate a potent CD8+ cytotoxic T lymphocyte (CTL) response in vitro. DCs are effectively sensitized with RNA in the absence of reagents commonly used to facilitate mammalian cell transfection. RNA encoding a chimeric CEA/LAMP-1 lysosomal targeting signal enhances the induction of CEA-specific CD4+ T cells, providing a strategy to induce T-help that may be necessary to generate and/or maintain an optimal CD8+ CTL response in vivo. CEA RNA-transfected DCs also serve as effective targets in cytotoxicity assays, thus providing a general method for inducing, as well as measuring, CEA-specific CTL responses across a broad spectrum of HLA haplotypes.

Authors
Nair, SK; Boczkowski, D; Morse, M; Cumming, RI; Lyerly, HK; Gilboa, E
MLA Citation
Nair, SK, Boczkowski, D, Morse, M, Cumming, RI, Lyerly, HK, and Gilboa, E. "Induction of primary carcinoembryonic antigen (CEA)-specific cytotoxic T lymphocytes in vitro using human dendritic cells transfected with RNA." Nat Biotechnol 16.4 (April 1998): 364-369.
PMID
9555728
Source
pubmed
Published In
Nature Biotechnology
Volume
16
Issue
4
Publish Date
1998
Start Page
364
End Page
369
DOI
10.1038/nbt0498-364

Induction of primary, human antigen-specific cytotoxic T lymphocytes in vitro using dendritic cells pulsed with peptides.

Using a murine metastasis model, we have previously shown that antigen-presenting cells (APC) loaded with unfractionated peptides derived from poorly immunogenic, highly metastatic tumor cells represent a potent form of tumor vaccine. The antimetastatic effect of peptide pulsed APC could be further enhanced by pretreating the cells with antisense oligonucleotides directed against the TAP-2 gene to increase the density of specific peptide-major histocompatibility complex (MHC) class I complexes and thereby improve the APC function of the treated cells (Nair SK et al., J Immunol 1996;156:1772). In this study, we investigated whether similar strategies can be used to enhance the potency of human dendritic cells (DC) to present antigen. We show that human DC pulsed with peptides encoding known cytotoxic T-lymphocyte (CTL) epitopes stimulate both memory and primary CTL responses in vitro after two cycles of stimulation with the peptide-pulsed DC. Two approaches were used to increase the density of specific peptide-MHC complexes on the surface of DC. One approach was to inhibit transporter associated with antigen presentation (TAP) function using TAP antisense oligonucleotides. The second approach was to inhibit the endogenous generation of the peptide epitopes by pretreating the DC with a proteasome inhibitor. Treatment of DC with either TAP antisense oligonucleotides or with a proteasome inhibitor resulted in a dramatic enhancement of primary CTL induction.

Authors
Wong, C; Morse, M; Nair, SK
MLA Citation
Wong, C, Morse, M, and Nair, SK. "Induction of primary, human antigen-specific cytotoxic T lymphocytes in vitro using dendritic cells pulsed with peptides." J Immunother 21.1 (January 1998): 32-40.
PMID
9456434
Source
pubmed
Published In
Journal of Immunotherapy
Volume
21
Issue
1
Publish Date
1998
Start Page
32
End Page
40

Correction: Dendritic cell/macrophage precursors capture exogenous antigen for MHC class I presentation by dendritic cells (European Journal of Immunology (1998) 28, 6 (1923-1933))

Authors
Mitchell, DA; Nair, SK; Gilboa, E
MLA Citation
Mitchell, DA, Nair, SK, and Gilboa, E. "Correction: Dendritic cell/macrophage precursors capture exogenous antigen for MHC class I presentation by dendritic cells (European Journal of Immunology (1998) 28, 6 (1923-1933))." European Journal of Immunology 28.11 (1998): 3891--.
Source
scival
Published In
European Journal of Immunology
Volume
28
Issue
11
Publish Date
1998
Start Page
3891-

Heparan sulfate modulate allogeneic T cell responses stimulated by dendritic cells

Heparan sulfate (HS) is a biologically active glycosaminoglycan which is released from cell surfaces or extracellular matrices under the circumstances of tissue injury or inflammation. We have reported previously that HS modulates T cell immune responses by direct activation of macrophages. Here, we examined the effect of free HS on dendritic cells (DC) as accessory cells in allogeneic mixed lymphocyte reactions. A T cell-enriched fraction of splenocytes from BALB/c mice was co-cultured with DC from C57BL/6 mice. DC were isolated from either spleen cells and cultured bone marrow cells with GM-CSF. Under suboptimal conditions (supplemented with 1% mouse serum), 103-104 DC treated with HS induced a greater allogeneic response than untreated DC. Counts per million at 4 days culture were as follows: splenic DC (103), 7751.3 +/- 1635.4 with HS vs. 1390.3 +/- 264.2 without, bone marrow DC (5×103), 6285.8 +/- 860.7 with HS vs. 1959.3 +/- 204.5 without. These results suggest that free HS may modulate cellular immune responses in the microenvironment of local inflammatory sites by providing inflammatory signals that modify the function of DC.

Authors
Kodaira, Y; Wrenshall, LE; Nair, S; Gilboa, E; Platt, JL
MLA Citation
Kodaira, Y, Wrenshall, LE, Nair, S, Gilboa, E, and Platt, JL. "Heparan sulfate modulate allogeneic T cell responses stimulated by dendritic cells." 1998.
Source
scival
Published In
The FASEB journal : official publication of the Federation of American Societies for Experimental Biology
Volume
12
Issue
4
Publish Date
1998
Start Page
A582

Immunotherapy of cancer with dendritic cell-based vaccines

Authors
Nair, SK
MLA Citation
Nair, SK. "Immunotherapy of cancer with dendritic cell-based vaccines." Gene Therapy 5.11 (1998): 1445-1446.
PMID
9930296
Source
scival
Published In
Gene Therapy
Volume
5
Issue
11
Publish Date
1998
Start Page
1445
End Page
1446

Cancer immunotherapy with tumor RNA transfected dendritic cell vaccines.

Authors
Nair, SK; Morse, M; Boczkowski, D; Lyerly, HK; Gilboa, E
MLA Citation
Nair, SK, Morse, M, Boczkowski, D, Lyerly, HK, and Gilboa, E. "Cancer immunotherapy with tumor RNA transfected dendritic cell vaccines." 1998.
Source
wos-lite
Published In
Journal of leukocyte biology
Publish Date
1998
Start Page
88
End Page
88

Immunotherapy of cancer with dendritic cell-based tumor vaccines

Authors
Gilboa, E; Nair, SK; Morse, M; Boczkowski, D; Deng, Y; Lyerly, HK
MLA Citation
Gilboa, E, Nair, SK, Morse, M, Boczkowski, D, Deng, Y, and Lyerly, HK. "Immunotherapy of cancer with dendritic cell-based tumor vaccines." 1998.
Source
wos-lite
Published In
Annals of Oncology
Volume
9
Publish Date
1998
Start Page
7
End Page
7

Direct demonstration of "cross-priming": In situ transfer of tumor antigen to dendritic cells

Authors
Mitchell, DA; Nair, SK; Snyder, D; Gilboa, E
MLA Citation
Mitchell, DA, Nair, SK, Snyder, D, and Gilboa, E. "Direct demonstration of "cross-priming": In situ transfer of tumor antigen to dendritic cells." 1998.
Source
wos-lite
Published In
Journal of leukocyte biology
Publish Date
1998
Start Page
71
End Page
71

Role of CD4(+) T cell help in priming in vivo CD8(+) CTL responses by dendritic cells

Authors
Faiola, B; Nair, SK; Doyle, C; Gilboa, E
MLA Citation
Faiola, B, Nair, SK, Doyle, C, and Gilboa, E. "Role of CD4(+) T cell help in priming in vivo CD8(+) CTL responses by dendritic cells." 1998.
Source
wos-lite
Published In
Journal of leukocyte biology
Publish Date
1998
Start Page
37
End Page
37

RNA transfected dendritic cell vaccines: Use of RNA amplified from tumor cells.

Authors
Boczkowski, D; Nair, SK; Synder, D; Gilboa, E
MLA Citation
Boczkowski, D, Nair, SK, Synder, D, and Gilboa, E. "RNA transfected dendritic cell vaccines: Use of RNA amplified from tumor cells." 1998.
Source
wos-lite
Published In
Journal of leukocyte biology
Publish Date
1998
Start Page
94
End Page
94

Bone marrow-generated dendritic cells pulsed with tumor extracts or tumor RNA induce antitumor immunity against central nervous system tumors.

Recent studies have shown that the brain is not a barrier to successful active immunotherapy that uses gene-modified autologous tumor cell vaccines. In this study, we compared the efficacy of two types of vaccines for the treatment of tumors within the central nervous system (CNS): dendritic cell (DC)-based vaccines pulsed with either tumor extract or tumor RNA, and cytokine gene-modified tumor vaccines. Using the B16/F10 murine melanoma (B16) as a model for CNS tumor, we show that vaccination with bone marrow-generated DCs, pulsed with either B16 cell extract or B16 total RNA, can induce specific cytotoxic T lymphocytes against B16 tumor cells. Both types of DC vaccines were able to protect animals from tumors located in the CNS. DC-based vaccines also led to prolonged survival in mice with tumors placed before the initiation of vaccine therapy. The DC-based vaccines were at least as effective, if not more so, as vaccines containing B16 tumor cells in which the granulocytic macrophage colony-stimulating factor gene had been modified. These data support the use of DC-based vaccines for the treatment of patients with CNS tumors.

Authors
Ashley, DM; Faiola, B; Nair, S; Hale, LP; Bigner, DD; Gilboa, E
MLA Citation
Ashley, DM, Faiola, B, Nair, S, Hale, LP, Bigner, DD, and Gilboa, E. "Bone marrow-generated dendritic cells pulsed with tumor extracts or tumor RNA induce antitumor immunity against central nervous system tumors." J Exp Med 186.7 (October 6, 1997): 1177-1182.
PMID
9314567
Source
pubmed
Published In
The Journal of Experimental Medicine
Volume
186
Issue
7
Publish Date
1997
Start Page
1177
End Page
1182

Regression of tumors in mice vaccinated with professional antigen-presenting cells pulsed with tumor extracts.

Vaccination with tumor extracts circumvents the need to identify specific tumor rejection antigens and extends the use of active immunotherapy to the vast majority of cancers, in which specific tumor antigens have not yet been identified. In this study we examined the efficacy of tumor vaccines comprised of unfractionated tumor material presented by professional antigen-presenting cells (APC): dendritic cells (DC) or macrophages (M phi). To enhance the relevance of these studies for human patients we used 2 poorly immunogenic murine tumor models and evaluated the effectiveness of the vaccination protocols in tumor-bearing animals. APC (in particular DC) pulsed with unfractionated extracts from these "poorly immunogenic" tumors were highly effective in eliciting tumor-specific cytotoxic T lymphocytes. A measurable CTL response could be detected after even a single immunization with tumor extract-pulsed DC. DC or M phi pulsed with tumor extract were also effective vaccines in tumor-bearing animals. In the murine bladder tumor (MBT-2) model a modest extension of survival and 40% cure rate was seen in the animal groups immunized with DC or M phi pulsed with MBT-2 tumor extract. DC or M phi pulsed with B16/F10.9 tumor extract were also remarkably effective in the B16 melanoma lung metastasis model, as shown by the observation that treatment with APC caused a significant reduction in lung metastases. Cumulatively, the CTL and immunotherapy data from the two murine tumor systems suggest that APC (in particular DC) pulsed with unfractionated cell extracts as a source of tumor antigen may be equally or more effective than genetically modified tumor vaccines.

Authors
Nair, SK; Snyder, D; Rouse, BT; Gilboa, E
MLA Citation
Nair, SK, Snyder, D, Rouse, BT, and Gilboa, E. "Regression of tumors in mice vaccinated with professional antigen-presenting cells pulsed with tumor extracts." Int J Cancer 70.6 (March 17, 1997): 706-715.
PMID
9096653
Source
pubmed
Published In
International Journal of Cancer
Volume
70
Issue
6
Publish Date
1997
Start Page
706
End Page
715

Antigen-presenting cells pulsed with unfractionated tumor-derived peptides are potent tumor vaccines.

Vaccination with peptides isolated from tumor cells circumvents the need for identifying specific tumor rejection antigens and extends the use of active immunotherapy to the majority of cancers where specific tumor antigens have not yet been identified. In this study, we examined the efficacy of tumor vaccines composed of unfractionated tumor peptides presented by antigen-presenting cells (APC) to induce cytotoxic T lymphocyte (CTL) responses and tumor immunity. RMA-S cells pulsed with peptides isolated from ovalbumin (OVA)-expressing tumor cells were highly effective at inducing primary, OVA-specific CTL responses in vitro and priming CTL responses in vivo. In addition, tumor peptide-pulsed RMA-S cells induced protective immunity in mice when challenged with OVA-expressing tumor cells. To enhance the clinical relevance of these studies, cells pulsed with tumor peptides were evaluated in the poorly immunogenic, B16/F10.9 melanoma post-surgical metastasis model. Treatment of tumor-bearing mice with peptide-pulsed RMA-S cells or with adherent splenocytes (enriched for professional APC) caused a significant reduction in lung metastases. The antimetastatic effect of peptide-pulsed splenocytes could be further enhanced by pretreating the cells with antisense oligonucleotides directed against the TAP-2 gene which was previously shown to increase the density of specific peptide/MHC class I complexes and thereby improve the APC function of the treated cells (Nair et el., J. Immunol. 1996. 156: 1772). This study suggests that APC loaded with unfractionated peptides derived from poorly immunogenic, highly metastatic tumor cells may represent a potent form of tumor vaccine.

Authors
Nair, SK; Boczkowski, D; Snyder, D; Gilboa, E
MLA Citation
Nair, SK, Boczkowski, D, Snyder, D, and Gilboa, E. "Antigen-presenting cells pulsed with unfractionated tumor-derived peptides are potent tumor vaccines." Eur J Immunol 27.3 (March 1997): 589-597.
PMID
9079797
Source
pubmed
Published In
European Journal of Immunology
Volume
27
Issue
3
Publish Date
1997
Start Page
589
End Page
597
DOI
10.1002/eji.1830270304

DNA vaccines and immunity to herpes simplex virus

Authors
Rouse, BT; Nair, S; Rouse, RJD; Yu, Z; Kuklin, N; Karem, K; Manickan, E
MLA Citation
Rouse, BT, Nair, S, Rouse, RJD, Yu, Z, Kuklin, N, Karem, K, and Manickan, E. "DNA vaccines and immunity to herpes simplex virus." Current Topics in Microbiology and Immunology 226 (1997): 69-78.
PMID
9479836
Source
scival
Published In
Current topics in microbiology and immunology
Volume
226
Publish Date
1997
Start Page
69
End Page
78

Immunotherapy of cancer with dendritic cell-based tumor vaccines

Authors
Gilboa, E; Nair, SK; Boczkowski, D; Mitchel, D; Faiola, B
MLA Citation
Gilboa, E, Nair, SK, Boczkowski, D, Mitchel, D, and Faiola, B. "Immunotherapy of cancer with dendritic cell-based tumor vaccines." 1997.
Source
wos-lite
Published In
Cancer Gene Therapy
Volume
4
Issue
5
Publish Date
1997
Start Page
314
End Page
314

Dendritic cells pulsed with RNA are potent antigen-presenting cells in vitro and in vivo.

Immunization with defined tumor antigens is currently limited to a small number of cancers where candidates for tumor rejection antigens have been identified. In this study we investigated whether pulsing dendritic cells (DC) with tumor-derived RNA is an effective way to induce CTL and tumor immunity. DC pulsed with in vitro synthesized chicken ovalbumin (OVA) RNA were more effective than OVA peptide-pulsed DC in stimulating primary, OVA-specific CTL responses in vitro. DC pulsed with unfractionated RNA (total or polyA+) from OVA-expressing tumor cells were as effective as DC pulsed with OVA peptide at stimulating CTL responses. Induction of OVA-specific CTL was abrogated when polyA+ RNA from OVA-expressing cells was treated with an OVA-specific antisense oligodeoxynucleotide and RNase H, showing that sensitization of DC was indeed mediated by OVA RNA. Mice vaccinated with DC pulsed with RNA from OVA-expressing tumor cells were protected against a challenge with OVA-expressing tumor cells. In the poorly immunogenic, highly metastatic, B16/F10.9 tumor model a dramatic reduction in lung metastases was observed in mice vaccinated with DC pulsed with tumor-derived RNA (total or polyA+, but not polyA- RNA). The finding that RNA transcribed in vitro from cDNA cloned in a bacterial plasmid was highly effective in sensitizing DC shows that amplification of the antigenic content from a small number of tumor cells is feasible, thus expanding the potential use of RNA-pulsed DC-based vaccines for patients bearing very small, possibly microscopic, tumors.

Authors
Boczkowski, D; Nair, SK; Snyder, D; Gilboa, E
MLA Citation
Boczkowski, D, Nair, SK, Snyder, D, and Gilboa, E. "Dendritic cells pulsed with RNA are potent antigen-presenting cells in vitro and in vivo." J Exp Med 184.2 (August 1, 1996): 465-472.
PMID
8760800
Source
pubmed
Published In
The Journal of Experimental Medicine
Volume
184
Issue
2
Publish Date
1996
Start Page
465
End Page
472

Cells treated with TAP-2 antisense oligonucleotides are potent antigen-presenting cells in vitro and in vivo.

Treatment of RMA and EL4 cells or freshly isolated splenocytes with antisense (AS) oligonucleotides directed against the TAP-2 gene recreates the phenotype seen in cells that are genetically deficient in TAP function. Cells incubated with AS oligonucleotides exhibit reduced MHC class I expression on the cell surface, which can be increased by incubating the oligonucleotide-treated cells at 28 degrees C or by adding MHC haplotype-matched peptides to the culture medium. RMA cells or splenocytes treated with AS oligonucleotides and incubated with peptide were highly effective in generating primary CTL responses in vitro. The bulk of the AS oligonucleotide-responsive and CTL-inducing cells resided in the adherent fraction of splenocytes. Moreover, TAP-2 AS oligonucleotide-treated adherent splenocytes pulsed with OVA peptide elicited potent OVA-specific CTL responses in vivo and provided effective protection from challenge with tumor cells expressing the corresponding Ag. AS oligonucleotide technology provides a simple approach to develop broadly applicable methods for generating potent APC to study TAP function in normal cells and to identify other gene products involved in MHC class I presentation.

Authors
Nair, SK; Snyder, D; Gilboa, E
MLA Citation
Nair, SK, Snyder, D, and Gilboa, E. "Cells treated with TAP-2 antisense oligonucleotides are potent antigen-presenting cells in vitro and in vivo." J Immunol 156.5 (March 1, 1996): 1772-1780.
PMID
8596026
Source
pubmed
Published In
Journal of immunology (Baltimore, Md. : 1950)
Volume
156
Issue
5
Publish Date
1996
Start Page
1772
End Page
1780

Priming for virus-specific CD8+ but not CD4+ cytotoxic T lymphocytes with synthetic lipopeptide is influenced by acylation units and liposome encapsulation.

Synthetic peptides of the herpes simplex virus glycoprotein B synthesized either as a free form or derivatized with one (PAM1) or three palmitic acids (PAM3Cys) were used to assess the in vivo priming efficacy of high affinity virus-specific CTL induction. The peptide and its derivatives were delivered in vivo with or without liposome encapsulation. Neither the free peptide nor the PAM1 derivative primed for high affinity virus specific CD8+ CTL induction, whether delivered via liposomes or not. On the other hand, the PAM3Cys derivative was able to prime for low levels of high affinity virus specific CD8+ CTL induction in the absence of liposome encapsulation. However, the efficiency of virus-specific CD8+ CTL induction with PAM3Cys derivative was enhanced following encapsulation in the liposomes. In contrast, all forms of the peptides induced both CD4+ T cell proliferative response as well as high affinity virus-specific CD4+ CTL. In addition, the efficiency of the PAM3Cys derivative to prime for CD4+ or CD8+ CTL was found to be influenced by the liposome encapsulation. When delivered via liposomes, the PAM3Cys derivative effectively primed for CD8+ CTL. However, liposomal delivery was not necessary for efficient priming for CD4+ CTL induction. Thus, both the acylation units as well as liposomal delivery appear to influence the in vivo priming of CD4+ and CD8+ T cell responses with synthetic peptides.

Authors
Babu, JS; Nair, S; Kanda, P; Rouse, BT
MLA Citation
Babu, JS, Nair, S, Kanda, P, and Rouse, BT. "Priming for virus-specific CD8+ but not CD4+ cytotoxic T lymphocytes with synthetic lipopeptide is influenced by acylation units and liposome encapsulation." Vaccine 13.17 (December 1995): 1669-1676.
PMID
8719518
Source
pubmed
Published In
Vaccine
Volume
13
Issue
17
Publish Date
1995
Start Page
1669
End Page
1676

Role of macrophages and dendritic cells in primary cytotoxic T lymphocyte responses.

The successful induction of class I restricted cytotoxic T lymphocytes (CTL) responses with soluble non-replicating antigens relies upon vehicles which deliver antigen in vivo appropriately to antigen presenting cells (APC), which for CTL may be dendritic cells (DC). In this study, we have followed the distribution of liposomes and their incorporated antigen and compared the efficacy of splenic macrophages (Mo) and DC at inducing primary CTL responses in vitro. Our results show that whereas liposomes locate predominantly in the splenic red pulp and marginal zone locations, some of their soluble antigen contents redistribute to the central white pulp, comprising mainly DC and T cells. Such antigen redistribution was most apparent following administration of pH-sensitive liposomes. In comparisons of the APC activity of Mo and DC taken at various times post-injection, DC were always superior to Mo. However, if Mo were depleted prior to antigen exposure, DC were ineffective APC for CTL induction. Furthermore, addition of supernatant from OVA-liposome treated Mo to naive DC-T cell cultures in vitro resulted in OVA-specific T cell responses. These studies indicate a role for Mo in enhancing the antigen presenting function of DC.

Authors
Nair, S; Buiting, AM; Rouse, RJ; Van Rooijen, N; Huang, L; Rouse, BT
MLA Citation
Nair, S, Buiting, AM, Rouse, RJ, Van Rooijen, N, Huang, L, and Rouse, BT. "Role of macrophages and dendritic cells in primary cytotoxic T lymphocyte responses." Int Immunol 7.4 (April 1995): 679-688.
PMID
7547695
Source
pubmed
Published In
International Immunology
Volume
7
Issue
4
Publish Date
1995
Start Page
679
End Page
688

Expression of cytokine mRNA in murine splenic dendritic cells and better induction of T cell-derived cytokines by dendritic cells than by macrophages during in vitro costimulation assay using specific antigens.

Among antigen-presenting cells dendritic cells (DC) have the unique ability to generate primary T cell response. The reasons for the superior inductive property of DC still remain obscure. The explanations offered include higher expression of CD80, MHCII, and ICAMI on DC surface which allows effective cluster formation with T cells. It is also possible that additional cellular characteristics of DC, i.e., their ability to release critical mediators involved in the induction of effective immune response, are important. We examined the ability of DC to express IL-1, IL-6, and IL-12 using the highly sensitive reverse transcription-quantitative polymerase chain reaction. Our data show that highly purified (97-99% pure) murine splenic DC were capable of expressing IL-1, IL-6 and IL-12 mRNA upon stimulation with lipopolysaccharide. We also compared the ability of DC and macrophages to induce T cell-derived cytokines IL-2 and IFN-gamma in an in vitro antigen-specific costimulation assay. In naive T cells stimulated with antigen presented via DC or macrophages, the levels of mRNA for IL-2 and IFN-gamma were 2- to 4-fold higher when cells were stimulated with DC. Overall, our data add additional support to the description of DC as superior antigen-presenting cells for the activation of naive T cells.

Authors
Kanangat, S; Nair, S; Babu, JS; Rouse, BT
MLA Citation
Kanangat, S, Nair, S, Babu, JS, and Rouse, BT. "Expression of cytokine mRNA in murine splenic dendritic cells and better induction of T cell-derived cytokines by dendritic cells than by macrophages during in vitro costimulation assay using specific antigens." J Leukoc Biol 57.2 (February 1995): 310-316.
PMID
7531747
Source
pubmed
Published In
Journal of leukocyte biology
Volume
57
Issue
2
Publish Date
1995
Start Page
310
End Page
316

Induction in vitro of primary cytotoxic T-lymphocyte responses with DNA encoding herpes simplex virus proteins.

Vaccines which successfully protect against virus infections usually need to induce a broadly reactive immune response which includes the induction of cytotoxic T lymphocytes (CTL). In this study, we have used a convenient in vitro approach to investigate if plasmid DNAs encoding proteins of herpes simplex virus (HSV) are capable of inducing primary CD8+ CTL. Dendritic cells or macrophages were transfected with either plasmid DNA encoding glycoprotein B or DNA encoding the immediate-early protein ICP27. These antigen-presenting cells (APC) were then used to stimulate enriched populations of naive T cells in microcultures for 5 days in vitro. Antigen-specific CD8+ CTL which reacted both with specific protein-expressing targets and with syngeneic targets infected with HSV could be demonstrated. Dendritic cells, as APC, generated the maximal responses, but such cells needed to be transfected with DNA in the presence of a cationic lipid. However, macrophages could act as APC when they were exposed to purified DNA. HSV-primed splenocytes were also shown to generate specific CTL responses when they were stimulated with purified DNA encoding ICP27. The novel approach described in this paper promises to be extremely useful, since defining immunogenicity profiles and identifying epitopes on viral proteins should be easier and more convenient when working with DNA and investigating variables in vitro. This is particularly the case with complex viruses such as HSV, most of whose encoded proteins have yet to be isolated in sufficient quantity or purity to perform in vivo immunological studies.

Authors
Rouse, RJ; Nair, SK; Lydy, SL; Bowen, JC; Rouse, BT
MLA Citation
Rouse, RJ, Nair, SK, Lydy, SL, Bowen, JC, and Rouse, BT. "Induction in vitro of primary cytotoxic T-lymphocyte responses with DNA encoding herpes simplex virus proteins." J Virol 68.9 (September 1994): 5685-5689.
PMID
8057449
Source
pubmed
Published In
Journal of virology
Volume
68
Issue
9
Publish Date
1994
Start Page
5685
End Page
5689

Cholera toxin acts as a potent adjuvant for the induction of cytotoxic T-lymphocyte responses with non-replicating antigens.

Cholera toxin (CT) is a strong systemic and mucosal adjuvant that greatly enhances IgG and IgA immune responses, but its adjuvant effects for cellular immunity, particularly class I-restricted cytotoxic T lymphocyte (CTL) responses, are less well understood. In the present report, CT and the purified non-toxic B component (CTB) were assessed for their ability to facilitate class I-restricted CTL induction to soluble proteins as well as to permit sensitization of target cells for CTL-mediated lysis. Priming for ovalbumin (OVA)-specific CTL occurred following oral exposure to a combination of OVA with CT plus CTB. In addition, CTB mixed with soluble proteins and administered intravenously primed mice for antigen-specific class I-restricted CTL. Target cells could also be sensitized for CTL-mediated killing following their exposure to soluble antigen and CTB in vitro. These results indicate that combinations of CT and CTB not only enhance antibody responses, but also have an immunomodulating effect to allow sensitization and priming for antigen-specific class I-restricted CTL.

Authors
Bowen, JC; Nair, SK; Reddy, R; Rouse, BT
MLA Citation
Bowen, JC, Nair, SK, Reddy, R, and Rouse, BT. "Cholera toxin acts as a potent adjuvant for the induction of cytotoxic T-lymphocyte responses with non-replicating antigens." Immunology 81.3 (March 1994): 338-342.
PMID
8206507
Source
pubmed
Published In
Immunology
Volume
81
Issue
3
Publish Date
1994
Start Page
338
End Page
342

Vaccination with the immediate-early protein ICP47 of herpes simplex virus-type 1 (HSV-1) induces virus-specific lymphoproliferation, but fails to protect against lethal challenge

Assessing the immunobiological function of the individual proteins of herpes simplex virus-type 1 (HSV-1) continues to be important in elucidating virus-host interactions and for the rational design of subunit vaccines. In this report, the non-structural, immediate-early protein ICP47 of HSV-1 was examined for its ability to induce virus-specific immune responses. The ICP47 protein, when expressed from a recombinant vaccinia virus or when produced by cell-free, in vitro translation, induced a vigorous HSV-1 specific lymphoproliferative response. However, other common parameters of immunity such as neutralizing antibody, delayed-type hypersensitivity, and class I major histocompatibility complex (MHC)-restricted cytotoxic T lymphocytes (CTL) were not induced by ICP47. Moreover, mice immunized with vaccinia- expressed ICP47 were unable to survive lethal challenge with virulent HSV, indicating that in spite of its ability to induce significant HSV-1-specific lymphoproliferation, ICP47 appears unable to afford protective immunity in vivo. Possible reasons for this failure and the implications of these results in terms of vaccine design are discussed.

Authors
Banks, TA; Jenkins, FJ; Kanangat, S; Nair, S; Dasgupta, S; Foster, CM; Rouse, BT
MLA Citation
Banks, TA, Jenkins, FJ, Kanangat, S, Nair, S, Dasgupta, S, Foster, CM, and Rouse, BT. "Vaccination with the immediate-early protein ICP47 of herpes simplex virus-type 1 (HSV-1) induces virus-specific lymphoproliferation, but fails to protect against lethal challenge." Virology 200.1 (1994): 236-245.
PMID
8128625
Source
scival
Published In
Virology
Volume
200
Issue
1
Publish Date
1994
Start Page
236
End Page
245
DOI
10.1006/viro.1994.1181

Induction of primary, antiviral cytotoxic, and proliferative responses with antigens administered via dendritic cells.

Cytotoxic T lymphocytes (CTL) play an essential role in recovery from viral infections, but induction of CTL responses with nonreplicating antigens is difficult to achieve. Exogenous antigens, such as viral proteins and peptides, normally induce CD4+ T-cell responses unless appropriately delivered to the major histocompatibility complex class I antigen presentation pathway. In vitro studies performed to address this issue revealed a similar scenario, and primary CTL induction with nonreplicating antigens has rarely been reported. This study demonstrated primary antiviral CTL induction in vitro with exogenous antigens delivered in vivo to dendritic cells. This study also evaluated the efficacy of glycoprotein B peptide (free or encapsulated in liposomes), peptide-tripalmitoyl-S-glyceryl cysteinyl conjugate (acylpeptide), and glycoprotein B protein encapsulated in pH-sensitive liposomes as antigen delivery vehicles. Our results show that higher levels of cytotoxicity against herpes simplex virus type 1 resulted from exposure of dendritic cells to peptide-tripalmitoyl-S-glyceryl cysteinyl in liposomes. Macrophages treated in a similar manner were not effective stimulators for primary CTL induction. Our data have relevance to the understanding of mechanisms of antigen processing and presentation and the design of antiviral vaccines.

Authors
Nair, S; Babu, JS; Dunham, RG; Kanda, P; Burke, RL; Rouse, BT
MLA Citation
Nair, S, Babu, JS, Dunham, RG, Kanda, P, Burke, RL, and Rouse, BT. "Induction of primary, antiviral cytotoxic, and proliferative responses with antigens administered via dendritic cells." J Virol 67.7 (July 1993): 4062-4069.
PMID
8510217
Source
pubmed
Published In
Journal of virology
Volume
67
Issue
7
Publish Date
1993
Start Page
4062
End Page
4069

Recognition by and in vitro induction of cytotoxic T lymphocytes against predicted epitopes of the immediate-early protein ICP27 of herpes simplex virus.

The identification of herpes simplex virus type 1 (HSV-1) proteins and the minimal epitopes within these proteins which serve as targets for cytotoxic T lymphocytes (CTL) remains an important goal for the development of effective vaccine strategies. In this report, an H-2Kd allele-specific peptide-binding motif was used to locate putative CTL epitopes in the HSV-1 immediate-early protein ICP27, a protein previously identified as a major CTL target in the BALB/c mouse. Peptides 1 (amino acids 322 to 332) and 2 (amino acids 448 to 456) synthesized to represent two separate predicted CTL epitopes in ICP27 were able to sensitize target cells in vitro for recognition by HSV-1-specific CTL. Moreover, using a recently developed system to generate primary CTL responses in vitro, both peptides induced primary CTL which reacted with target cells expressing HSV-1. This system allowed us to verify the activity of two CTL epitopes in the ICP27 protein and holds promise as a rapid way of identifying immunogenic peptides from any protein molecule.

Authors
Banks, TA; Nair, S; Rouse, BT
MLA Citation
Banks, TA, Nair, S, and Rouse, BT. "Recognition by and in vitro induction of cytotoxic T lymphocytes against predicted epitopes of the immediate-early protein ICP27 of herpes simplex virus." J Virol 67.1 (January 1993): 613-616.
PMID
7677961
Source
pubmed
Published In
Journal of virology
Volume
67
Issue
1
Publish Date
1993
Start Page
613
End Page
616

Class I restricted CTL recognition of a soluble protein delivered by liposomes containing lipophilic polylysines.

CD8+ cytotoxic lymphocytes recognize peptides derived from endogenous antigens complexed with class I major histocompatibility complex while CD4+ helper cells recognize peptides from exogenous antigens bound to class II MHC molecules. A soluble protein can be introduced into the class I pathway of antigen processing and presentation using an appropriate vehicle to deliver the antigen into the cytosol. Cationic liposomes containing lipophilic polylysine readily form complexes with an anionic, soluble protein ovalbumin. Mouse thymoma EL4 cells incubated with such complexes can be sensitized for killing by OVA-specific CTL effector cells. This method of target sensitization by a soluble antigen is more sensitive than the osmotic loading method previously reported.

Authors
Nair, S; Zhou, X; Huang, L; Rouse, BT
MLA Citation
Nair, S, Zhou, X, Huang, L, and Rouse, BT. "Class I restricted CTL recognition of a soluble protein delivered by liposomes containing lipophilic polylysines." J Immunol Methods 152.2 (August 10, 1992): 237-243.
PMID
1386866
Source
pubmed
Published In
Journal of Immunological Methods
Volume
152
Issue
2
Publish Date
1992
Start Page
237
End Page
243

In vivo cytotoxic T lymphocyte induction with soluble proteins administered in liposomes.

The in vivo induction of a CTL response usually requires that Ag be endogenously synthesized so that appropriate processing can occur. In most of the few examples where successful CTL induction was reported with proteins and peptides, unacceptable adjuvants or means of Ag formulation were used. In the present report, liposomes were used to incorporate the soluble proteins OVA and beta-galactosidase. This simple and convenient to use approach, which requires minimal amounts of Ag, results in priming for a CD8+ CTL response and the establishment of immunologic memory. The liposome approach may not only prove a convenient means of inducing CTL responses in vivo but may also be useful to study the mechanisms of Ag processing.

Authors
Reddy, R; Zhou, F; Nair, S; Huang, L; Rouse, BT
MLA Citation
Reddy, R, Zhou, F, Nair, S, Huang, L, and Rouse, BT. "In vivo cytotoxic T lymphocyte induction with soluble proteins administered in liposomes." J Immunol 148.5 (March 1, 1992): 1585-1589.
PMID
1538138
Source
pubmed
Published In
Journal of immunology (Baltimore, Md. : 1950)
Volume
148
Issue
5
Publish Date
1992
Start Page
1585
End Page
1589

Soluble proteins delivered to dendritic cells via pH-sensitive liposomes induce primary cytotoxic T lymphocyte responses in vitro.

Effective immunity to many infectious agents, particularly viruses, requires a CD8+ cytotoxic T lymphocyte (CTL) response. Understanding how to achieve CTL induction with soluble proteins is important for vaccine development since such antigens are usually not processed appropriately to induce CTL. In the present report, we have demonstrated that a potent primary CTL response against a soluble protein can be achieved by delivering antigen in pH-sensitive liposomes to dendritic cells (DC) either in vivo or in vitro. Since the pH-sensitive liposome delivery system is efficient and easy to use, the approach promises to be valuable both in the study of basic mechanisms in antigen processing, and as a practical means of immunization.

Authors
Nair, S; Zhou, F; Reddy, R; Huang, L; Rouse, BT
MLA Citation
Nair, S, Zhou, F, Reddy, R, Huang, L, and Rouse, BT. "Soluble proteins delivered to dendritic cells via pH-sensitive liposomes induce primary cytotoxic T lymphocyte responses in vitro." J Exp Med 175.2 (February 1, 1992): 609-612.
PMID
1531064
Source
pubmed
Published In
The Journal of Experimental Medicine
Volume
175
Issue
2
Publish Date
1992
Start Page
609
End Page
612

Liposomes as antigen delivery systems in viral immunity

Since their first description, liposomes have been put to a wide variety of uses. Encapsulation or incorporation of antigens into liposomes markedly enhances the immunogenicity of the antigen. The type of immune response elicited by the liposome is found to depend on their chemical and structural properties. Immunization with viral glycoproteins encapsulated in liposomes has resulted in enhancement of the humoral response seen as a rise in the serum antibody levels which is several fold higher than that elicited by free antigen alone. Furthermore, liposome encapsulation of peptide antigens which are poor immunogens by themselves not only increases the immunogenicity of the peptide but also play an important role in delivery. The adjuvant effect afforded by liposomes can be further enhanced by the concomitant encapsulation of adjuvants like lipid A or muramyl tripeptide-phosphatidylethanolamine. Formation of liposomes with special characteristics such as pH sensitivity has resulted in the use of liposomes to deliver soluble antigen to the cytosol where it can undergo class I pathway of processing and presentation. Therefore liposomes could provide valuable tools to further understand the pathways of antigen processing and the requirements for induction of cell mediated immunity. © 1992 by W.B. Saunders Company.

Authors
Ready, R; Nair, S; Brynestad, K; Rouse, BT
MLA Citation
Ready, R, Nair, S, Brynestad, K, and Rouse, BT. "Liposomes as antigen delivery systems in viral immunity." Seminars in Immunology 4.2 (1992): 91-96.
PMID
1535521
Source
scival
Published In
Seminars in Immunology
Volume
4
Issue
2
Publish Date
1992
Start Page
91
End Page
96

Liposomal delivery of soluble protein antigens for class I MHC-mediated antigen presentation

Authors
Huang, L; Reddy, R; Nair, SK; Zhou, F; Rouse, BT
MLA Citation
Huang, L, Reddy, R, Nair, SK, Zhou, F, and Rouse, BT. "Liposomal delivery of soluble protein antigens for class I MHC-mediated antigen presentation." Research in Immunology 143.2 (1992): 192-196.
PMID
1574646
Source
scival
Published In
Research in Immunology
Volume
143
Issue
2
Publish Date
1992
Start Page
192
End Page
196
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