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Seighali N, Shafiee A, Rafiee MA, Aminzade D, Mozhgani SH. Human T-cell lymphotropic virus type 1 (HTLV-1) proposed vaccines: a systematic review of preclinical and clinical studies. BMC Infect Dis 2023; 23:320. [PMID: 37170214 PMCID: PMC10173209 DOI: 10.1186/s12879-023-08289-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 04/27/2023] [Indexed: 05/13/2023] Open
Abstract
BACKGROUND Numerous vaccination research experiments have been conducted on non-primate hosts to prevent or control HTLV-1 infection. Therefore, reviewing recent advancements for status assessment and strategic planning of future preventative actions to reduce HTLV-1 infection and its consequences would be essential. METHODS MEDLINE, Scopus, Web of Science, and Clinicaltrials.gov were searched from each database's inception through March 27, 2022. All original articles focusing on developing an HTLV-1 vaccine candidate were included. RESULTS A total of 47 studies were included. They used a variety of approaches to develop the HTLV-1 vaccine, including DNA-based, dendritic-cell-based, peptide/protein-based, and recombinant vaccinia virus approaches. The majority of the research that was included utilized Tax, Glycoprotein (GP), GAG, POL, REX, and HBZ as their main peptides in order to develop the vaccine. The immunization used in dendritic cell-based investigations, which were more recently published, was accomplished by an activated CD-8 T-cell response. Although there hasn't been much attention lately on this form of the vaccine, the initial attempts to develop an HTLV-1 immunization depended on recombinant vaccinia virus, and the majority of results seem positive and effective for this type of vaccine. Few studies were conducted on humans. Most of the studies were experimental studies using animal models. Adenovirus, Cytomegalovirus (CMV), vaccinia, baculovirus, hepatitis B, measles, and pox were the most commonly used vectors. CONCLUSIONS This systematic review reported recent progression in the development of HTLV-1 vaccines to identify candidates with the most promising preventive and therapeutic effects.
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Affiliation(s)
- Niloofar Seighali
- Student Research Committee, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran
| | - Arman Shafiee
- Student Research Committee, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran
| | - Mohammad Ali Rafiee
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Dlnya Aminzade
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sayed-Hamidreza Mozhgani
- Department of Microbiology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran.
- Non-Communicable Disease Research Center, Alborz University of Medical Sciences, Karaj, Iran.
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Selective APC-targeting of a novel Fc-fusion multi-immunodominant recombinant protein ( tTax- tEnv:mFcγ2a) for HTLV-1 vaccine development. Life Sci 2022; 308:120920. [PMID: 36044973 DOI: 10.1016/j.lfs.2022.120920] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 11/22/2022]
Abstract
AIMS HTLV-1 causes two life-threatening diseases: adult T-cell leukaemia/lymphoma and HTLV-1-associated myelopathy/tropical spastic paraparesis. Due to the lack of proper treatment, an effective HTLV-1 vaccine is urgently needed. MAIN METHODS DNA sequences of 11-19 and 178-186 amino acids of HTLV-1-Tax and SP2 and P21 were fused to the mouse-Fcγ2a, or His-tag called tTax-tEnv:mFcγ2a and tTax-tEnv:His, respectively. These constructs were produced in Pichia pastoris, and their immunogenicity and protective properties were assessed in a mouse challenging model with an HTLV-1-MT2 cell line. KEY FINDINGS The immunogenicity assessments showed significant increase in IFN-γ production in animals receiving tTax-tEnv:mFcγ2a (1537.2 ± 292.83 pg/mL) compared to tTax-tEnv:His (120.28 ± 23.9, p = 0.02). IL-12 production also increased in group receiving tTax-tEnv:mFcγ2a than tTax-tEnv:His group, (23 ± 2.6 vs 1.5 ± 0.6, p = 0.01), respectively. The IFN-γ and IL-12 levels in the Fc-immunised group were negatively correlated with PVL (R = -0.82, p < 0.04) and (R = -0.87, p = 0.05), respectively. While, IL-4 was increased by tTax-tEnv:His (21.16 ± 1.76 pg/mL) compared to tTax-tEnv:mFcγ2a (13.7 ± 1.49, p = 0.019) with a negative significant correlation to PVL (R = -0.95, p = 0.001). SIGNIFICANCE The mouse challenging assay with tTax-tEnv:mFcγ2a showed 50 % complete protection and a 50 % low level of HTLV-1-PVL compared to the positive control receiving HTLV-1-MT2 (p = 0.001). Challenging experiments for the His-tag protein showed the same outcome (p = 0.002) but by different mechanisms. The Fc-fusion construct induced more robust Th1, and His-tag protein shifted more to Th2 immune responses. Therefore, inducing both T helper responses, but a Th1/Th2 balance in favour of Th1 might be necessary for appropriate protection against HTLV-1 infection, spreading via cell-to-cell contact manner.
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Pan L, Weng R, Zhang J, Wang J, Tang Y, Deng N. Immune Response of the VEGF/bFGF Complex Peptide Vaccine and Function of Immune Antibodies in Inhibiting Migration of HUVEC Cells and Proliferation of Cancer Cells. Int J Pept Res Ther 2014. [DOI: 10.1007/s10989-014-9414-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Tamai Y, Hasegawa A, Takamori A, Sasada A, Tanosaki R, Choi I, Utsunomiya A, Maeda Y, Yamano Y, Eto T, Koh KR, Nakamae H, Suehiro Y, Kato K, Takemoto S, Okamura J, Uike N, Kannagi M. Potential Contribution of a Novel Tax Epitope–Specific CD4+T Cells to Graft-versus-Tax Effect in Adult T Cell Leukemia Patients after Allogeneic Hematopoietic Stem Cell Transplantation. THE JOURNAL OF IMMUNOLOGY 2013; 190:4382-92. [DOI: 10.4049/jimmunol.1202971] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Rodríguez SM, Florins A, Gillet N, de Brogniez A, Sánchez-Alcaraz MT, Boxus M, Boulanger F, Gutiérrez G, Trono K, Alvarez I, Vagnoni L, Willems L. Preventive and therapeutic strategies for bovine leukemia virus: lessons for HTLV. Viruses 2011; 3:1210-48. [PMID: 21994777 PMCID: PMC3185795 DOI: 10.3390/v3071210] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2011] [Revised: 06/28/2011] [Accepted: 06/29/2011] [Indexed: 01/06/2023] Open
Abstract
Bovine leukemia virus (BLV) is a retrovirus closely related to the human T-lymphotropic virus type 1 (HTLV-1). BLV is a major animal health problem worldwide causing important economic losses. A series of attempts were developed to reduce prevalence, chiefly by eradication of infected cattle, segregation of BLV-free animals and vaccination. Although having been instrumental in regions such as the EU, these strategies were unsuccessful elsewhere mainly due to economic costs, management restrictions and lack of an efficient vaccine. This review, which summarizes the different attempts previously developed to decrease seroprevalence of BLV, may be informative for management of HTLV-1 infection. We also propose a new approach based on competitive infection with virus deletants aiming at reducing proviral loads.
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Affiliation(s)
- Sabrina M. Rodríguez
- Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA), University of Liège (ULg), 4000, Liège, Belgium; E-Mails: (S.M.R.); (N.G.); (F.B.)
| | - Arnaud Florins
- Molecular and Cellular Biology, Gembloux Agro-Bio Tech, University of Liège (ULg), 5030, Gembloux, Belgium; E-Mails: (A.F.); (A.d.B.); (M.T.S.-A.); (M.B.)
| | - Nicolas Gillet
- Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA), University of Liège (ULg), 4000, Liège, Belgium; E-Mails: (S.M.R.); (N.G.); (F.B.)
| | - Alix de Brogniez
- Molecular and Cellular Biology, Gembloux Agro-Bio Tech, University of Liège (ULg), 5030, Gembloux, Belgium; E-Mails: (A.F.); (A.d.B.); (M.T.S.-A.); (M.B.)
| | - María Teresa Sánchez-Alcaraz
- Molecular and Cellular Biology, Gembloux Agro-Bio Tech, University of Liège (ULg), 5030, Gembloux, Belgium; E-Mails: (A.F.); (A.d.B.); (M.T.S.-A.); (M.B.)
| | - Mathieu Boxus
- Molecular and Cellular Biology, Gembloux Agro-Bio Tech, University of Liège (ULg), 5030, Gembloux, Belgium; E-Mails: (A.F.); (A.d.B.); (M.T.S.-A.); (M.B.)
| | - Fanny Boulanger
- Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA), University of Liège (ULg), 4000, Liège, Belgium; E-Mails: (S.M.R.); (N.G.); (F.B.)
| | - Gerónimo Gutiérrez
- Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, INTA, C.C. 1712, Castelar, Argentina; E-Mails: (G.G.); (K.T.); (I.A.); (L.V.)
| | - Karina Trono
- Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, INTA, C.C. 1712, Castelar, Argentina; E-Mails: (G.G.); (K.T.); (I.A.); (L.V.)
| | - Irene Alvarez
- Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, INTA, C.C. 1712, Castelar, Argentina; E-Mails: (G.G.); (K.T.); (I.A.); (L.V.)
| | - Lucas Vagnoni
- Instituto de Virología, Centro de Investigaciones en Ciencias Veterinarias y Agronómicas, INTA, C.C. 1712, Castelar, Argentina; E-Mails: (G.G.); (K.T.); (I.A.); (L.V.)
| | - Luc Willems
- Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA), University of Liège (ULg), 4000, Liège, Belgium; E-Mails: (S.M.R.); (N.G.); (F.B.)
- Molecular and Cellular Biology, Gembloux Agro-Bio Tech, University of Liège (ULg), 5030, Gembloux, Belgium; E-Mails: (A.F.); (A.d.B.); (M.T.S.-A.); (M.B.)
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Mirshahidi S, Kramer VG, Whitney JB, Essono S, Lee S, Dranoff G, Anderson KS, Ruprecht RM. Overlapping synthetic peptides encoding TPD52 as breast cancer vaccine in mice: prolonged survival. Vaccine 2009; 27:1825-33. [PMID: 19201387 PMCID: PMC4477950 DOI: 10.1016/j.vaccine.2009.01.089] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Revised: 01/13/2009] [Accepted: 01/16/2009] [Indexed: 12/21/2022]
Abstract
Peptide-based vaccines, one of several anti-tumor immunization strategies currently under investigation, can elicit both MHC Class I-restricted (CD8(+)) and Class II-restricted (CD4(+)) responses. However, the need to identify specific T-cell epitopes in the context of MHC alleles has hampered the application of this approach. We have tested overlapping synthetic peptides (OSP) representing a tumor antigen as a novel approach that bypasses the need for epitope mapping, since OSP contain all possible epitopes for both CD8(+) and CD4(+) T cells. Here we report that vaccination of inbred and outbred mice with OSP representing tumor protein D52 (TPD52-OSP), a potential tumor antigen target for immunotherapy against breast, prostate, and ovarian cancer, was safe and induced specific CD8(+) and CD4(+) T-cell responses, as demonstrated by development of specific cytotoxic T cell (CTL) activity, proliferative responses, interferon (IFN)-gamma production and CD107a/b expression in all mice tested. In addition, TPD52-OSP-vaccinated BALB/c mice were challenged with TS/A breast carcinoma cells expressing endogenous TPD52; significant survival benefits were noted in vaccine recipients compared to unvaccinated controls (p<0.001). Our proof-of-concept data demonstrate the safety and efficacy of peptide library-based cancer vaccines that obviates the need to identify epitopes or MHC backgrounds of the vaccinees. We show that an OSP vaccination approach can assist in the disruption of self-tolerance and conclude that our approach may hold promise for immunoprevention of early-stage cancers in a general population.
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Affiliation(s)
- Saied Mirshahidi
- Department of Cancer Immunology & AIDS, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA, 02115
- Department of Medicine, Harvard Medical School, 44 Binney St, Boston, MA, 02115
| | - Victor G. Kramer
- Department of Cancer Immunology & AIDS, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA, 02115
| | - James B. Whitney
- Department of Cancer Immunology & AIDS, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA, 02115
- Department of Medicine, Harvard Medical School, 44 Binney St, Boston, MA, 02115
| | - Sosthène Essono
- Department of Cancer Immunology & AIDS, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA, 02115
- Department of Medicine, Harvard Medical School, 44 Binney St, Boston, MA, 02115
| | - Sandra Lee
- Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA, 02115
- Harvard School of Public Health, 44 Binney St, Boston, MA, 02115
| | - Glenn Dranoff
- Department of Medicine, Harvard Medical School, 44 Binney St, Boston, MA, 02115
- Department of Medical Oncology, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA, 02115
| | - Karen S. Anderson
- Department of Medicine, Harvard Medical School, 44 Binney St, Boston, MA, 02115
- Department of Medical Oncology, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA, 02115
| | - Ruth M. Ruprecht
- Department of Cancer Immunology & AIDS, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA, 02115
- Department of Medicine, Harvard Medical School, 44 Binney St, Boston, MA, 02115
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Abstract
Our understanding of the importance of CD4+ T cells in orchestrating immune responses has grown dramatically over the past decade. This lymphocyte family consists of diverse subsets ranging from interferon-gamma (IFN-gamma)-producing T-helper 1 (Th1) cells to transforming growth factor-beta (TGF-beta)-secreting T-regulatory cells, which have opposite roles in modulating immune responses to pathogens, tumor cells, and self-antigens. This review briefly addresses the various T-cell subsets within the CD4+ T-cell family and discusses recent research efforts aimed at elucidating the nature of the 'T-cell help' that has been shown to be essential for optimal immune function. Particular attention is paid to the role of Th cells in tumor immunotherapy. We review some of our own work in the field describing how CD4+ Th cells can enhance anti-tumor cytotoxic T-lymphocyte (CTL) responses by enhancing clonal expansion at the tumor site, preventing activation-induced cell death and functioning as antigen-presenting cells for CTLs to preferentially generate immune memory cells. These unconventional roles for Th lymphocytes, which require direct cell-to-cell communication with CTLs, are clear examples of how versatile these immunoregulatory cells are.
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Affiliation(s)
- Richard Kennedy
- Mayo Vaccine Research Group, Mayo Clinic College of Medicine, Rochester, MN, USA
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8
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Kobayashi H, Celis E. Peptide epitope identification for tumor-reactive CD4 T cells. Curr Opin Immunol 2008; 20:221-7. [PMID: 18499419 DOI: 10.1016/j.coi.2008.04.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Revised: 03/20/2008] [Accepted: 04/25/2008] [Indexed: 10/22/2022]
Abstract
Because T lymphocytes have the capacity to recognize tumor cells, significant efforts are being devoted towards the development of T cell-based immunotherapy for cancer. Most of this work has centered in the induction of anti-tumor CD8 T cells, which exhibit cytolytic activity towards tumor cells expressing tumor-specific or tumor associated antigens. Unfortunately to this day, T cell-based immunotherapy for cancer remains suboptimal. One of the possible explanations is that these immunotherapies have ignored the role that CD4 T helper lymphocytes play in the generation and persistence of CD8 T cell responses. Thus, we believe that in order to obtain clinical benefits T cell-based immunotherapy must stimulate both CD8 and CD4 tumor-reactive T cell responses. During the past seven years our group has focused on the identification of CD4 T cell epitopes from tumor-associated and tumor-specific antigens that could be used to complement the already identified CD8 T cell epitopes to produce effective vaccination strategies against numerous tumor types. We will describe here the strategy we used that resulted in the identification and characterization of numerous CD4 T cell epitopes that are applicable to developing therapies against hematological malignancies and solid tumors.
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Affiliation(s)
- Hiroya Kobayashi
- Department of Pathology, Asahikawa Medical College, Asahikawa, Japan
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Kobayashi H, Nagato T, Takahara M, Sato K, Kimura S, Aoki N, Azumi M, Tateno M, Harabuchi Y, Celis E. Induction of EBV-latent membrane protein 1-specific MHC class II-restricted T-cell responses against natural killer lymphoma cells. Cancer Res 2008; 68:901-8. [PMID: 18245493 DOI: 10.1158/0008-5472.can-07-3212] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
EBV-encoded latent membrane protein 1 (LMP1) has oncogenic potential and is expressed in many EBV-associated malignancies. Although LMP1 is regarded as a potential tumor-associated antigen for immunotherapy and several LMP1-specific MHC class I-restricted CTL epitopes have been reported, little is known regarding MHC class II-restricted CD4 helper T-lymphocyte (HTL) epitopes for LMP1. The goal of the present studies was to determine whether MHC class II-restricted CD4 T-cell responses could be induced against the LMP1 antigen and to evaluate the antitumor effect of these responses. We have combined the use of a predictive MHC class II binding peptide algorithm with in vitro vaccination of CD4 T cells using candidate peptides to identify naturally processed epitopes derived from LMP1 that elicit immune responses against EBV-expressing tumor cells. Peptide LMP1(159-175) was effective in inducing HTL responses that were restricted by HLA-DR9, HLA-DR53, or HLA-DR15, indicating that this peptide behaves as a promiscuous T-cell epitope. Moreover, LMP1(159-175)-reactive HTL clones directly recognized EBV lymphoblastoid B cells, EBV-infected natural killer (NK)/T-lymphoma cells and naturally processed antigen in the form of LMP1+ tumor cell lysates presented by autologous dendritic cells. Because the newly identified epitope LMP1(159-175) overlaps with an HLA-A2-restricted CTL epitope (LMP1(159-167)), this peptide might have the ability to induce simultaneous CTL and HTL responses against LMP1. Overall, our data should be relevant for the design and optimization of T-cell epitope-based immunotherapy against various EBV-associated malignancies, including NK/T cell lymphomas.
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Affiliation(s)
- Hiroya Kobayashi
- Department of Pathology, Asahikawa Medical College, Asahikawa, Japan
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Pandya D, Rahman S, Wigdahl B, Khan ZK, Jain P. New insights into the pathogenesis, diagnosis and treatment of human T-cell leukemia virus type 1-induced disease. Future Virol 2007. [DOI: 10.2217/17460794.2.5.481] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
It has been over 25 years since the discovery of human T-cell leukemia virus type 1 (HTLV-1); however, the exact sequence of events that occur during primary infection, clinical latency or the development of disease remains unresolved. The advances in molecular virology and neuroimmunology have contributed significantly to our understanding of HTLV-1 pathogenesis, but also uncovered the complexity of the virus–host interaction both in the peripheral blood and the CNS. Here, we overview the general pathologic features of HTLV-1, molecular mechanisms of oncogenic transformation and characteristics of the host immune response during the associated neuroinflammatory process. We also discuss both current and new approaches in the diagnosis and therapy of HTLV-1 associated diseases – adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. Finally, potentially important emerging areas of research that may have an impact on our understanding of the pathogenic mechanism have been briefly introduced.
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Affiliation(s)
- Devanshi Pandya
- Drexel University College of Medicine, Department of Microbiology & Immunology, and, Center for Cancer Biology, Institute for Molecular Medicine & Infectious Disease, Philadelphia, PA 19102, USA
| | - Saifur Rahman
- Drexel University College of Medicine, Department of Microbiology & Immunology, and, Center for Cancer Biology, Institute for Molecular Medicine & Infectious Disease, Philadelphia, PA 19102, USA
| | - Brian Wigdahl
- Drexel University College of Medicine, Department of Microbiology & Immunology, and, Center for Cancer Biology, Institute for Molecular Medicine & Infectious Disease, Philadelphia, PA 19102, USA
| | - Zafar K Khan
- Drexel University College of Medicine, Department of Microbiology & Immunology, and, Center for Cancer Biology, Institute for Molecular Medicine & Infectious Disease, Philadelphia, PA 19102, USA
| | - Pooja Jain
- Drexel University College of Medicine, Department of Microbiology & Immunology, Institute for Molecular Medicine & Infectious Disease, New College Building, Room 18311, 245 North 15th Street, Philadelphia, PA 19102, USA
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Kobayashi H, Nagato T, Sato K, Aoki N, Kimura S, Murakami M, Iizuka H, Azumi M, Kakizaki H, Tateno M, Celis E. Recognition of prostate and melanoma tumor cells by six-transmembrane epithelial antigen of prostate-specific helper T lymphocytes in a human leukocyte antigen class II-restricted manner. Cancer Res 2007; 67:5498-504. [PMID: 17545632 DOI: 10.1158/0008-5472.can-07-0304] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The six-transmembrane epithelial antigen of prostate (STEAP) protein is an attractive candidate for T cell-based immunotherapy because it is overexpressed in prostate cancer and various other tumor types. Several peptide epitopes capable of stimulating CTLs that killed STEAP-expressing tumor cells have been described. Our goal was the identification of helper T lymphocyte (HTL) epitopes of STEAP for the optimization of T cell-based immunotherapies against STEAP-expressing malignancies. Candidate HTL epitopes for STEAP were predicted using in silico algorithms for HLA class II-binding peptides and were tested for their ability to elicit HTL responses by in vitro peptide vaccination of CD4 T lymphocytes from healthy individuals and prostate cancer patients. Two peptides (STEAP(102-116) and STEAP(192-206)) were effective in stimulating in vitro antitumor HTL responses in both normal individuals and prostate cancer patients. Notably, both STEAP HTL peptides behaved as promiscuous T-cell epitopes because they stimulated T cells in the context of more than one MHC class II allele. These newly described STEAP HTL epitopes could be of value for the design and optimization of T cell-based immunotherapy against STEAP-expressing tumors.
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Affiliation(s)
- Hiroya Kobayashi
- Department of Pathology, Asahikawa Medical College, Asahikawa, Japan
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