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Silva RCMC, Panis C, Pires BRB. Lessons from transmissible cancers for immunotherapy and transplant. Immunol Med 2021; 45:146-161. [PMID: 34962854 DOI: 10.1080/25785826.2021.2018783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
The emergence of horizontal transmission of cancer between vertebrates is an issue that interests scientists and medical society. Transmission requires: (i) a mechanism by which cancer cells can transfer to another organism and (ii) a repressed immune response on the part of the recipient. Transmissible tumors are unique models to comprehend the responses and mechanisms mediated by the major histocompatibility complex (MHC), which can be transposed for transplant biology. Here, we discuss the mechanisms involved in immune-mediated tissue rejection, making a parallel with transmissible cancers. We also discuss cellular and molecular mechanisms involved in cancer immunotherapy and anti-rejection therapies.
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Affiliation(s)
- Rafael Cardoso Maciel Costa Silva
- Laboratory of Immunoreceptors and Signaling, Instituto de Biofísica Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio De Janeiro, Brazil
| | - Carolina Panis
- Laboratory of Tumor Biology, State University of West Paraná, UNIOESTE, Francisco Beltrão, Brazil
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2
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Cruz-Adalia A, Ramirez-Santiago G, Osuna-Pérez J, Torres-Torresano M, Zorita V, Martínez-Riaño A, Boccasavia V, Borroto A, Martínez Del Hoyo G, González-Granado JM, Alarcón B, Sánchez-Madrid F, Veiga E. Conventional CD4 + T cells present bacterial antigens to induce cytotoxic and memory CD8 + T cell responses. Nat Commun 2017; 8:1591. [PMID: 29147022 PMCID: PMC5691066 DOI: 10.1038/s41467-017-01661-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 10/06/2017] [Indexed: 01/15/2023] Open
Abstract
Bacterial phagocytosis and antigen cross-presentation to activate CD8+ T cells are principal functions of professional antigen presenting cells. However, conventional CD4+ T cells also capture and kill bacteria from infected dendritic cells in a process termed transphagocytosis (also known as transinfection). Here, we show that transphagocytic T cells present bacterial antigens to naive CD8+ T cells, which proliferate and become cytotoxic in response. CD4+ T-cell-mediated antigen presentation also occurs in vivo in the course of infection, and induces the generation of central memory CD8+ T cells with low PD-1 expression. Moreover, transphagocytic CD4+ T cells induce protective anti-tumour immune responses by priming CD8+ T cells, highlighting the potential of CD4+ T cells as a tool for cancer immunotherapy. Antigen presentation is generally considered the domain of innate immune cells, but CD4+ T cells can transphagocytose bacteria from infected dendritic cells. Here the authors show CD4+ T cells can transphagocytose bacterial and tumour antigens and present them to CD8+ T cells to activate memory and cytotoxic functions.
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Affiliation(s)
- Aránzazu Cruz-Adalia
- Department of Molecular & Cellular Biology, Centro Nacional de Biotecnología; Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, 28049, Madrid, Spain.
| | - Guillermo Ramirez-Santiago
- Department of Molecular & Cellular Biology, Centro Nacional de Biotecnología; Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, 28049, Madrid, Spain.,Hospital de Santa Cristina, Instituto de Investigación Sanitaria Princesa, 28009, Madrid, Spain
| | - Jesús Osuna-Pérez
- Department of Molecular & Cellular Biology, Centro Nacional de Biotecnología; Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, 28049, Madrid, Spain
| | - Mónica Torres-Torresano
- Department of Molecular & Cellular Biology, Centro Nacional de Biotecnología; Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, 28049, Madrid, Spain
| | - Virgina Zorita
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Melchor Fernández Almagro 3, 28029, Madrid, Spain
| | - Ana Martínez-Riaño
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa (CBMSO); Nicolás Cabrera 1, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Viola Boccasavia
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa (CBMSO); Nicolás Cabrera 1, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Aldo Borroto
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa (CBMSO); Nicolás Cabrera 1, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Gloria Martínez Del Hoyo
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Melchor Fernández Almagro 3, 28029, Madrid, Spain
| | - José María González-Granado
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Melchor Fernández Almagro 3, 28029, Madrid, Spain.,Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), 28041, Madrid, Spain
| | - Balbino Alarcón
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa (CBMSO); Nicolás Cabrera 1, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | | | - Esteban Veiga
- Department of Molecular & Cellular Biology, Centro Nacional de Biotecnología; Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, 28049, Madrid, Spain.
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3
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Durlanik S, Loyal L, Stark R, Sercan Alp Ö, Hartung A, Radbruch A, von Herrath M, Matzmohr N, Frentsch M, Thiel A. CD40L expression by CD4 + but not CD8 + T cells regulates antiviral immune responses in acute LCMV infection in mice. Eur J Immunol 2016; 46:2566-2573. [PMID: 27562840 DOI: 10.1002/eji.201646420] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 06/29/2016] [Accepted: 08/24/2016] [Indexed: 12/16/2022]
Abstract
CD40-CD40 ligand (CD40L) signaling plays multiple indispensable roles in cellular and humoral immunity. Impaired memory T-cell responses in the absence of CD40L have been well documented, but the requirement of this interaction for efficient priming of CD8+ T cells especially under inflammatory conditions has been under debate. In contrast to previous publications, we report here that virus-specific CD8+ T-cell responses as well as viral clearance are affected not only in the memory but also in the effector phase in CD40L-/- mice infected with lymphocytic choriomeningitis virus (LCMV) Armstrong strain. Interestingly, a considerable part of the LCMV-specific effector and memory T cells consists of CD40L+ CD8+ T cells. However, deficiency of CD40L in CD8+ T cells did influence neither the quantity nor the quality of primary T-cell responses in LCMV infection. Virus-specific CD8+ T cells in conditional knockout mice, with a selective deletion of the CD40L in CD8+ T cells, were fully functional regarding cytokine production and efficient pathogen clearance. Thus, our results unambiguously demonstrate that while CD40L is critical to generate effective primary CD8+ T-cell responses also under inflammatory conditions, CD40L expression by CD8+ T cells themselves is dispensable in acute LCMV infection.
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Affiliation(s)
- Sibel Durlanik
- Regenerative Immunology and Aging, Berlin-Brandenburger Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany.,Cellular Biology, German Rheumatism Research Center (DRFZ), Institute of the Leibniz Association, Berlin, Germany
| | - Lucie Loyal
- Regenerative Immunology and Aging, Berlin-Brandenburger Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Regina Stark
- Regenerative Immunology and Aging, Berlin-Brandenburger Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany.,Department of Hematopoiesis, Sanquin Research and Landsteiner Laboratory, Amsterdam, the Netherlands
| | - Özen Sercan Alp
- Cellular Biology, German Rheumatism Research Center (DRFZ), Institute of the Leibniz Association, Berlin, Germany
| | - Anett Hartung
- Regenerative Immunology and Aging, Berlin-Brandenburger Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Andreas Radbruch
- Cellular Biology, German Rheumatism Research Center (DRFZ), Institute of the Leibniz Association, Berlin, Germany
| | - Matthias von Herrath
- Type 1 Diabetes Center, La Jolla Institute for Allergy and Immunology, La Jolla, CA, USA.,Novo Nordisk Diabetes Research and Development Center, Seattle, WA, USA
| | - Nadine Matzmohr
- Regenerative Immunology and Aging, Berlin-Brandenburger Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany.,Unit 303, Efficacy and Safety Assessment of Veterinary Drugs, Federal Office of Consumer Protection and Food Safety (BVL), Berlin, Germany
| | - Marco Frentsch
- Regenerative Immunology and Aging, Berlin-Brandenburger Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Andreas Thiel
- Regenerative Immunology and Aging, Berlin-Brandenburger Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany.
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4
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Berrien-Elliott MM, Jackson SR, Meyer JM, Rouskey CJ, Nguyen TLM, Yagita H, Greenberg PD, DiPaolo RJ, Teague RM. Durable adoptive immunotherapy for leukemia produced by manipulation of multiple regulatory pathways of CD8+ T-cell tolerance. Cancer Res 2012. [PMID: 23188506 DOI: 10.1158/0008-5472.can-12-2179] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Tolerizing mechanisms within the host and tumor microenvironment inhibit T-cell effector functions that can control cancer. These mechanisms blunt adoptive immunotherapy with infused T-cells due to a complex array of signals that determine T-cell tolerance, survival, or deletion. Ligation of the negative regulatory receptors CTLA4, PD-1(PDCD1), or LAG3 on T-cells normally hinders their response to antigen through nonredundant biochemical processes that interfere with stimulatory pathways. In this study, we used an established mouse model of T-cell tolerance to define the roles of these inhibitory receptors in regulating CD8(+) T-cell tolerance during adoptive immunotherapy to treat leukemia. Blocking CTLA4 and PD-1 in vivo combined to promote survival of transferred T-cells despite powerful deletional signals that mediate Bim (BCL2L11)-dependent apoptosis. However, this dual blockade was not optimal for stimulating effector function by responding T-cells, which required the additional blockade of LAG3 to induce full expansion and allow the acquisition of robust cytolytic activity. Thus, the cooperation of multiple distinct regulatory pathways was needed for the survival and effector differentiation of adoptively transferred tumor-reactive CD8(+) T-cells. Our work defines the immune escape pathways in which simultaneous blockade could yield durable immunotherapeutic responses that can eradicate disseminated leukemia.
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Affiliation(s)
- Melissa M Berrien-Elliott
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, Missouri 63104, USA
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5
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Ahmed KA, Wang L, Munegowda MA, Mulligan SJ, Mulligan S, Gordon JR, Griebel P, Xiang J. Direct in vivo evidence of CD4+ T cell requirement for CTL response and memory via pMHC-I targeting and CD40L signaling. J Leukoc Biol 2012; 92:289-300. [PMID: 22544940 DOI: 10.1189/jlb.1211631] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
CD4(+) T cell help contributes critically to DC-induced CD8(+) CTL immunity. However, precisely how these three cell populations interact and how CD4(+) T cell signals are delivered to CD8(+) T cells in vivo have been unclear. In this study, we developed a novel, two-step approach, wherein CD4(+) T cells and antigen-presenting DCs productively engaged one another in vivo in the absence of cognate CD8(+) T cells, after which, we selectively depleted the previously engaged CD4(+) T cells or DCs before allowing interactions of either population alone with naïve CD8(+) T cells. This protocol thus allows us to clearly document the importance of CD4(+) T-licensed DCs and DC-primed CD4(+) T cells in CTL immunity. Here, we provide direct in vivo evidence that primed CD4(+) T cells or licensed DCs can stimulate CTL response and memory, independent of DC-CD4(+) T cell clusters. Our results suggest that primed CD4(+) T cells with acquired pMHC-I from DCs represent crucial "immune intermediates" for rapid induction of CTL responses and for functional memory via CD40L signaling. Importantly, intravital, two-photon microscopy elegantly provide unequivocal in vivo evidence for direct CD4-CD8(+) T cell interactions via pMHC-I engagement. This study corroborates the coexistence of direct and indirect mechanisms of T cell help for a CTL response in noninflammatory situations. These data suggest a new "dynamic model of three-cell interactions" for CTL immunity derived from stimulation by dissociated, licensed DCs, primed CD4(+) T cells, and DC-CD4(+) T cell clusters and may have significant implications for autoimmunity and vaccine design.
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Affiliation(s)
- Khawaja Ashfaque Ahmed
- Research Unit, Saskatchewan Cancer Agency, Department of Oncology, University of Saskatchewan, Saskatoon, Saskatchewan Canada
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Meunier S, Rapetti L, Beziaud L, Pontoux C, Legrand A, Tanchot C. Synergistic CD40 signaling on APCs and CD8 T cells drives efficient CD8 response and memory differentiation. J Leukoc Biol 2012; 91:859-69. [PMID: 22241832 DOI: 10.1189/jlb.0611292] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The role of CD4 help during CD8 response and memory differentiation has been clearly demonstrated in different experimental models. However, the exact mechanisms of CD4 help remain largely unknown and preclude replacement therapy to develop. Interestingly, studies have shown that administration of an agonist aCD40ab can substitute CD4 help in vitro and in vivo, whereas the targets of this antibody remain elusive. In this study, we address the exact role of CD40 expression on APCs and CD8 T cells using aCD40ab treatment in mice. We demonstrate that aCD40 antibodies have synergetic effects on APCs and CD8 T cells. Full efficiency of aCD40 treatment requires CD40 expression on both populations: if one of these cell populations is CD40-deficient, the CD8 T cell response is impaired. Most importantly, direct CD40 signaling on APCs and CD8 T cells affects CD8 T cell differentiation differently. In our model, CD40 expression on APCs plays an important but dispensable role on CD8 T cell expansion and effector functions during the early phase of the immune response. Conversely, CD40 on CD8 T cells is crucial and nonredundant for their progressive differentiation into memory cells. Altogether, these results highlight that CD40-CD40L-dependent and independent effects of CD4 help to drive a complete CD8 T cell differentiation.
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Affiliation(s)
- Sylvain Meunier
- Institut National de la Santé et de la Recherche Médicale, INSERM U1020, Paris, France
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7
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CD4+ T cell regulation of CD25 expression controls development of short-lived effector CD8+ T cells in primary and secondary responses. Proc Natl Acad Sci U S A 2009; 107:193-8. [PMID: 19966302 DOI: 10.1073/pnas.0909945107] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Both CD4(+) T cell help and IL-2 have been postulated to "program" activated CD8(+) T cells for memory cell development. However, the linkage between these two signals has not been well elucidated. Here we have studied effector and memory CD8(+) T cell differentiation following infection with three pathogens (Listeria monocytogenes, vesicular stomatitis virus, and vaccinia virus) in the absence of both CD4(+) T cells and IL-2 signaling. We found that expression of CD25 on antigen-specific CD8(+) T cells peaked 3-4 days after initial priming and was dependent on CD4(+) T cell help, likely through a CD28:CD80/86 mediated pathway. CD4(+) T cell or CD25-deficiency led to normal early effector CD8(+) T cell differentiation, but a subsequent lack of accumulation of CD8(+) T cells resulting in overall decreased memory cell generation. Interestingly, in both primary and recall responses KLRG1(high) CD127(low) short-lived effector cells were drastically diminished in the absence of IL-2 signaling, although memory precursors remained intact. In contrast to previous reports, upon secondary antigen encounter CD25-deficient CD8(+) T cells were capable of undergoing robust expansion, but short-lived effector development was again impaired. Thus, these results demonstrated that CD4(+) T cell help and IL-2 signaling were linked via CD25 up-regulation, which controls the expansion and differentiation of antigen-specific effector CD8(+) T cells, rather than "programming" memory cell traits.
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8
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Fuse S, Tsai CY, Molloy MJ, Allie SR, Zhang W, Yagita H, Usherwood EJ. Recall responses by helpless memory CD8+ T cells are restricted by the up-regulation of PD-1. THE JOURNAL OF IMMUNOLOGY 2009; 182:4244-54. [PMID: 19299723 DOI: 10.4049/jimmunol.0802041] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
CD4 help is crucial for memory CD8(+) T cell development, yet the mechanisms of CD4 help and why (CD4) helpless memory CD8(+) T cells elicit poor recall responses are currently not well understood. In this study we investigated these questions using an in vivo acute virus infection model. We show herein that CD4 help during priming is required for memory CD8(+) T cell differentiation, and that stimulation of CD40 during priming rescues the helpless defects in the absence of CD4(+) T cells. The defective recall response by helpless memory cells did not correlate with the amount of cell death and was independent of TRAIL. However, helpless memory cells excessively up-regulated the inhibitory receptor PD-1 (programmed cell death-1), and PD-1 blockade enhanced the recall response of helpless memory cells. Furthermore, providing IL-2 signaling in vivo during the recall response reduced PD-1 expression and rescued the recall response of helpless memory cells. Our study identifies molecular pathways involved in CD4 help for memory CD8(+) T cell generation that are independent of TRAIL, and it provides therapeutic implications that helpless memory cell function can be restored at multiple stages through various immunological interventions.
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Affiliation(s)
- Shinichiro Fuse
- Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH 03756, USA
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9
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Rapetti L, Meunier S, Pontoux C, Tanchot C. CD4 Help Regulates Expression of Crucial Genes Involved in CD8 T Cell Memory and Sensitivity to Regulatory Elements. THE JOURNAL OF IMMUNOLOGY 2008; 181:299-308. [DOI: 10.4049/jimmunol.181.1.299] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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10
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Hernandez MGH, Shen L, Rock KL. CD40 on APCs Is Needed for Optimal Programming, Maintenance, and Recall of CD8+T Cell Memory Even in the Absence of CD4+T Cell Help. THE JOURNAL OF IMMUNOLOGY 2008; 180:4382-90. [DOI: 10.4049/jimmunol.180.7.4382] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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11
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Agnellini P, Wiesel M, Schwarz K, Wolint P, Bachmann MF, Oxenius A. Kinetic and Mechanistic Requirements for Helping CD8 T Cells. THE JOURNAL OF IMMUNOLOGY 2008; 180:1517-25. [DOI: 10.4049/jimmunol.180.3.1517] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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12
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Otahal P, Knowles BB, Tevethia SS, Schell TD. Anti-CD40 conditioning enhances the T(CD8) response to a highly tolerogenic epitope and subsequent immunotherapy of simian virus 40 T antigen-induced pancreatic tumors. THE JOURNAL OF IMMUNOLOGY 2007; 179:6686-95. [PMID: 17982058 DOI: 10.4049/jimmunol.179.10.6686] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Rapid loss of adoptively transferred tumor-specific CD8(+) T cells (T(CD8)) following Ag recognition in the periphery and their limited accumulation within the tumor stroma reduces the effectiveness of T cell-based immunotherapy. To better understand the role of T(CD8) in the control of autochthonous tumors, we have used mice of the RIP1-Tag4 lineage that develop pancreatic beta cell tumors due to expression of the SV40 large T Ag from the rat insulin promoter. We previously showed that the kinetics of functional T(CD8) tolerance varies toward two distinct epitopes derived from T Ag. Epitope I ((206)SAINNYAQKL(215))-specific T(CD8) are rapidly deleted whereas T(CD8) targeting epitope IV ((404)VVYDFLKC(411)) persist over the lifetime of tumor-bearing animals. In this report, we show that the conditioning of tumor-bearing RIP1-Tag4 mice with agonistic anti-CD40 Ab induces extensive expansion of naive epitope I-specific TCR transgenic (TCR-I) T cells in this tolerogenic environment and delays their loss from the host. In addition, functional TCR-I T cells intensively infiltrate pancreatic tumors, resulting in increased survival of RIP1-Tag4 mice. These results suggest that a similar approach could effectively enhance T cell-based immunotherapies to cancer when targeting other highly tolerogenic epitopes.
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Affiliation(s)
- Pavel Otahal
- Department of Microbiology and Immunology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
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13
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Rocha B, Tanchot C. The Tower of Babel of CD8+ T-cell memory: known facts, deserted roads, muddy waters, and possible dead ends. Immunol Rev 2006; 211:182-96. [PMID: 16824127 DOI: 10.1111/j.0105-2896.2006.00378.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Adequate antigen stimulation can lead to permanent modifications of primed cells and to the generation of memory T cells that have astonishingly improved capacities to deal with antigen. The overall properties of memory T cells (increased survival, precocious and increased division capacities, and improved effector functions) can be used to identify this unique cell type. However, each immune response may lead to the generation of multiple primed types that do not necessarily possess all these characteristics. It is not known whether these different cell types are just side products of the immune reaction or whether they are involved in disease control. Control of different infections may involve different challenges and lead to the generation of different types of immune reactions. Our major challenge is to unravel this complexity, but we must overcome our handicapped experimental tests and our imperfect a priori definitions.
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Affiliation(s)
- Benedita Rocha
- INSERM U591, Institut Necker, Faculty of Medecine René Descartes Paris V, Paris, France.
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14
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Shi M, Hao S, Chan T, Xiang J. CD4(+) T cells stimulate memory CD8(+) T cell expansion via acquired pMHC I complexes and costimulatory molecules, and IL-2 secretion. J Leukoc Biol 2006; 80:1354-63. [PMID: 16980510 DOI: 10.1189/jlb.0506321] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The rapid and efficient expansion of CD8(+) memory T cells after the second encounter with a pathogen constitutes a hallmark trait of adaptive immunity. Yet, the contribution of CD4(+) T cells to the expansion of memory CD8(+) T cells remains the subject of controversy. Here, we show that, antigen-specific CD4(+) T cells, once activated by dendritic cells (DC) in vitro, have the capacity to stimulate expansion of memory CD8(+) T cells in vivo. The memory CD8(+) T cell expansion triggered by active CD4(+) T cells are mediated through DC-derived MHC I/peptide complexes and CD80 molecules displayed on the active CD4(+) T cells, with the involvement of IL-2 secreted by the active CD4(+) T cells. These results highlight a previously undescribed role of active CD4(+) T cells in triggering expansion of memory CD8(+) T cells.
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Affiliation(s)
- Meiqing Shi
- Saskatchewan Cancer Agency, Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, 20 Campus Dr., Saskatoon S7N 4H4, Canada
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15
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Abstract
A critical aim of vaccine-related research is to identify the mechanisms by which memory T cells are formed and maintained over long periods of time. In recent years, we have designed experiments aimed at addressing two key questions: (i) what are the factors that maintain functionally responsive CD8+ memory cells over long periods of time, and (ii) what are the signals during the early stages of infection that drive the differentiation of long-lived CD8+ memory T cells? We have identified a role for CD4+ T cells in the generation of CD8+ T-cell-mediated protection from secondary challenge. While CD4+ T cells appear to play a role in the programme of CD8 memory, we find that they are also required for the long-term maintenance of CD8+ memory T-cell numbers and function. This property is independent of CD40-CD40L interactions, and we propose a role for CD4+ T cells in maintaining the ability of CD8+ memory T cells to respond to interleukin-7 (IL-7) and IL-15. By manipulating both the time course of infection and the timing of antigen presentation to newly recruited CD8+ T cells, we also demonstrate that the programming of effector and memory potential are at least partially distinct processes.
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Affiliation(s)
- Matthew A Williams
- Department of Immunology and Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA
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