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Son ET, Faridi P, Paul-Heng M, Leong ML, English K, Ramarathinam SH, Braun A, Dudek NL, Alexander IE, Lisowski L, Bertolino P, Bowen DG, Purcell AW, Mifsud NA, Sharland AF. The self-peptide repertoire plays a critical role in transplant tolerance induction. J Clin Invest 2021; 131:e146771. [PMID: 34428180 PMCID: PMC8553557 DOI: 10.1172/jci146771] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 08/18/2021] [Indexed: 11/17/2022] Open
Abstract
While direct allorecognition underpins both solid organ allograft rejection and tolerance induction, the specific molecular targets of most directly alloreactive CD8+ T cells have not been defined. In this study, we used a combination of genetically engineered major histocompatibility complex class I (MHC I) constructs, mice with a hepatocyte-specific mutation in the class I antigen-presentation pathway, and immunopeptidomic analysis to provide definitive evidence for the contribution of the peptide cargo of allogeneic MHC I molecules to transplant tolerance induction. We established a systematic approach for the discovery of directly recognized pMHC epitopes and identified 17 strongly immunogenic H-2Kb-associated peptides recognized by CD8+ T cells from B10.BR (H-2k) mice, 13 of which were also recognized by BALB/c (H-2d) mice. As few as 5 different tetramers used together were able to identify a high proportion of alloreactive T cells within a polyclonal population, suggesting that there are immunodominant allogeneic MHC-peptide complexes that can account for a large component of the alloresponse.
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Affiliation(s)
- Eric T. Son
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia
| | - Pouya Faridi
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Moumita Paul-Heng
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia
| | - Mario L. Leong
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia
| | - Kieran English
- Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Sri H. Ramarathinam
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Asolina Braun
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Nadine L. Dudek
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Ian E. Alexander
- Gene Therapy Research Unit, Children’s Medical Research Institute, The University of Sydney, Faculty of Medicine and Health and Sydney Children’s Hospitals Network, Westmead, New South Wales, Australia
- The University of Sydney, Sydney Medical School, Discipline of Child and Adolescent Health, Westmead, New South Wales, Australia
| | - Leszek Lisowski
- Translational Vectorology Research Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, Australia
- Vector and Genome Engineering Facility, Children’s Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, Australia
- Military Institute of Medicine, Laboratory of Molecular Oncology and Innovative Therapies, Warsaw, Poland
| | - Patrick Bertolino
- Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - David G. Bowen
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia
- Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Anthony W. Purcell
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Nicole A. Mifsud
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Alexandra F. Sharland
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, New South Wales, Australia
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2
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Paul-Heng M, Leong M, Cunningham E, Bunker DLJ, Bremner K, Wang Z, Wang C, Tay SS, McGuffog C, Logan GJ, Alexander IE, Hu M, Alexander SI, Sparwasser TD, Bertolino P, Bowen DG, Bishop GA, Sharland A. Direct recognition of hepatocyte-expressed MHC class I alloantigens is required for tolerance induction. JCI Insight 2018; 3:97500. [PMID: 30089715 DOI: 10.1172/jci.insight.97500] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 06/28/2018] [Indexed: 12/31/2022] Open
Abstract
Adeno-associated viral vector-mediated (AAV-mediated) expression of allogeneic major histocompatibility complex class I (MHC class I) in recipient liver induces donor-specific tolerance in mouse skin transplant models in which a class I allele (H-2Kb or H-2Kd) is mismatched between donor and recipient. Tolerance can be induced in mice primed by prior rejection of a donor-strain skin graft, as well as in naive recipients. Allogeneic MHC class I may be recognized by recipient T cells as an intact molecule (direct recognition) or may be processed and presented as an allogeneic peptide in the context of self-MHC (indirect recognition). The relative contributions of direct and indirect allorecognition to tolerance induction in this setting are unknown. Using hepatocyte-specific AAV vectors encoding WT allogeneic MHC class I molecules, or class I molecules containing a point mutation (D227K) that impedes direct recognition of intact allogeneic MHC class I by CD8+ T cells without hampering the presentation of processed peptides derived from allogeneic MHC class I, we show here that tolerance induction depends upon recognition of intact MHC class I. Indirect recognition alone yielded a modest prolongation of subsequent skin graft survival, attributable to the generation of CD4+ Tregs, but it was not sufficient to induce tolerance.
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Affiliation(s)
- Moumita Paul-Heng
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Mario Leong
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Eithne Cunningham
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Daniel L J Bunker
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Katherine Bremner
- Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - Zane Wang
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Chuanmin Wang
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Szun Szun Tay
- Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - Claire McGuffog
- Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - Grant J Logan
- Gene Therapy Research Unit, Children's Medical Research Institute, The University of Sydney, Faculty of Medicine and Health and Sydney Children's Hospitals Network, Westmead, Australia
| | - Ian E Alexander
- Gene Therapy Research Unit, Children's Medical Research Institute, The University of Sydney, Faculty of Medicine and Health and Sydney Children's Hospitals Network, Westmead, Australia.,The University of Sydney, Sydney Medical School, Discipline of Child and Adolescent Health, Westmead, Australia
| | - Min Hu
- Centre for Transplant and Renal Research, Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW, Australia
| | - Stephen I Alexander
- Centre for Kidney Research, Children's Hospital at Westmead, The University of Sydney, NSW, Australia
| | - Tim D Sparwasser
- Institute of Infection Immunology, Twincore, Centre for Experimental and Clinical Infection Research, Hannover Medical School, Germany
| | - Patrick Bertolino
- Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - David G Bowen
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, NSW, Australia.,Liver Immunology Group and AW Morrow Gastroenterology and Liver Centre, The University of Sydney and Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - G Alex Bishop
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Alexandra Sharland
- Transplantation Immunobiology Group, University of Sydney Central Clinical School, Charles Perkins Centre, Faculty of Medicine and Health, Sydney, NSW, Australia
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3
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Mannose receptor induces T-cell tolerance via inhibition of CD45 and up-regulation of CTLA-4. Proc Natl Acad Sci U S A 2016; 113:10649-54. [PMID: 27601670 DOI: 10.1073/pnas.1605885113] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The mannose receptor (MR) is an endocytic receptor involved in serum homeostasis and antigen presentation. Here, we identify the MR as a direct regulator of CD8(+) T-cell activity. We demonstrate that MR expression on dendritic cells (DCs) impaired T-cell cytotoxicity in vitro and in vivo. This regulatory effect of the MR was mediated by a direct interaction with CD45 on the T cell, inhibiting its phosphatase activity, which resulted in up-regulation of cytotoxic T-lymphocyte-associated Protein 4 (CTLA-4) and the induction of T-cell tolerance. Inhibition of CD45 prevented expression of B-cell lymphoma 6 (Bcl-6), a transcriptional inhibitor that directly bound the CTLA-4 promoter and regulated its activity. These data demonstrate that endocytic receptors expressed on DCs contribute to the regulation of T-cell functionality.
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4
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Marquez EA, Kane KP. Identities of P2 and P3 Residues of H-2Kb-Bound Peptides Determine Mouse Ly49C Recognition. PLoS One 2015; 10:e0131308. [PMID: 26147851 PMCID: PMC4493100 DOI: 10.1371/journal.pone.0131308] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 05/31/2015] [Indexed: 11/18/2022] Open
Abstract
Ly49 receptors can be peptide selective in their recognition of MHC-I-peptide complexes, affording them a level of discrimination beyond detecting the presence or absence of specific MHC-I allele products. Despite this ability, little is understood regarding the properties that enable some peptides, when bound to MHC-I molecules, to support Ly49 recognition, but not others. Using RMA-S target cells expressing MHC-I molecules loaded with individual peptides and effector cells expressing the ectodomain of the inhibitory Ly49C receptor, we found that two adjacent amino acid residues, P2 and P3, both buried in the peptide binding groove of H-2Kb, determine mouse Ly49C specificity. If both are aliphatic residues, this is supportive. Whereas, small amino acids at P2 and aromatic amino acids at the P3 auxiliary anchor residue are detrimental to Ly49C recognition. These results resemble those with a rat Ly49 where the identity of a peptide anchor residue determines recognition, suggesting that dependence on specific peptide residues buried in the MHC-I peptide-binding groove may be fundamental to Ly49 peptide selectivity and recognition.
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Affiliation(s)
- Elsa A. Marquez
- Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Kevin P. Kane
- Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
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5
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Antigen expression level threshold tunes the fate of CD8 T cells during primary hepatic immune responses. Proc Natl Acad Sci U S A 2014; 111:E2540-9. [PMID: 24927525 DOI: 10.1073/pnas.1406674111] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
CD8 T-cell responses to liver-expressed antigens range from deletional tolerance to full effector differentiation resulting in overt hepatotoxicity. The reasons for these heterogeneous outcomes are not well understood. To identify factors that govern the fate of CD8 T cells activated by hepatocyte-expressed antigen, we exploited recombinant adenoassociated viral vectors that enabled us to vary potential parameters determining these outcomes in vivo. Our findings reveal a threshold of antigen expression within the liver as the dominant factor determining T-cell fate, irrespective of T-cell receptor affinity or antigen cross-presentation. Thus, when a low percentage of hepatocytes expressed cognate antigen, high-affinity T cells developed and maintained effector function, whereas, at a high percentage, they became functionally exhausted and silenced. Exhaustion was not irreversibly determined by initial activation, but was maintained by high intrahepatic antigen load during the early phase of the response; cytolytic function was restored when T cells primed under high antigen load conditions were transferred into an environment of low-level antigen expression. Our study reveals a hierarchy of factors dictating the fate of CD8 T cells during hepatic immune responses, and provides an explanation for the different immune outcomes observed in a variety of immune-mediated liver pathologic conditions.
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6
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Cippà PE, Gabriel SS, Kraus AK, Chen J, Wekerle T, Guimezanes A, Wüthrich RP, Fehr T. Bcl-2 inhibition to overcome memory cell barriers in transplantation. Am J Transplant 2014; 14:333-42. [PMID: 24472193 DOI: 10.1111/ajt.12554] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 10/14/2013] [Accepted: 10/17/2013] [Indexed: 01/25/2023]
Abstract
Memory T cells (Tm) represent a major barrier for immunosuppression and tolerance induction after solid organ transplantation. Taking into consideration the critical role of the intrinsic apoptosis pathway in the generation and maintenance of Tm, we developed a new concept to deplete alloreactive Tm by targeting Bcl-2 proteins. The small-molecule Bcl-2/Bcl-XL inhibitor ABT-737 efficiently induced apoptosis in alloreactive Tm in vitro and in vivo and prolonged skin graft survival in sensitized recipients. A short course of ABT-737 induction therapy prevented Tm-mediated resistance in a donor-specific transfusion model and allowed mixed chimerism induction across Tm barriers. Since Bcl-2 inhibitors yielded encouraging safety results in cancer trials, this novel approach might represent a substantial advance to prevent allograft rejection and induce tolerance in sensitized recipients.
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Affiliation(s)
- P E Cippà
- Institute of Physiology, University of Zürich, Zürich, Switzerland; Division of Nephrology, University Hospital Zürich, Zürich, Switzerland
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7
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Abstract
The mammalian immune system has evolved to display peptides derived from microbial antigens to immune effector cells. Liberated from the intact antigens through distinct proteolytic mechanisms, these peptides are subsequently transported to the cell surface while bound to chaperone-like receptors known as major histocompatibility complex molecules. These complexes are then scrutinized by T-cells that express receptors with specificity for specific major histocompatibility complex-peptide complexes. In normal uninfected cells, this process of antigen processing and presentation occurs continuously, with the resultant array of self-antigen-derived peptides displayed on the surface of these cells. Changes in this cellular peptide array alert the immune system to changes in the intracellular environment that may be associated with infection, oncogenesis or other abnormal cellular processes, resulting in a cascade of events that result in the elimination of the abnormal cell. Since peptides play such an essential role in informing the immune system of infection with viral or microbial pathogens and the transformation of cells in malignancy, the tools of proteomics, in particular mass spectrometry, are ideally suited to study these immune responses at a molecular level. Recent advances in studies of immune responses that have utilized mass spectrometry and associated technologies are reviewed. The authors gaze into the future and look at current challenges and where proteomics will impact in immunology over the next 5 years.
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Affiliation(s)
- Nicholas A Williamson
- The University of Melbourne, Department of Biochemistry & Molecular Biology, The Bio21 Molecular Science & Biotechnology Institute, 3010, Victoria, Australia.
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8
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Alloreactive cytotoxic T cells provide means to decipher the immunopeptidome and reveal a plethora of tumor-associated self-epitopes. Proc Natl Acad Sci U S A 2013; 111:403-8. [PMID: 24344295 DOI: 10.1073/pnas.1306549111] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
HLA molecules presenting peptides derived from tumor-associated self-antigens (self-TAA) are attractive targets for T-cell-based immunotherapy of cancer. However, detection of such epitopes is hampered by self-tolerance and limitations in the sensitivity of mass spectrometry. Here, we used T cells from HLA-A2-negative donors as tools to detect HLA-A2-bound peptides from two leukemia-associated differentiation antigens; CD20 and the previously undescribed cancer target myeloperoxidase. A high-throughput platform for epitope discovery was designed using dendritic cells cotransfected with full-length transcripts of self-TAA and HLA-A2 to allow presentation of all naturally processed peptides from a predefined self-protein on foreign HLA. Antigen-reactive T cells were directly detected using panels of color-coded peptide-HLA multimers containing epitopes predicted by a computer algorithm. Strikingly, cytotoxic T cells were generated against 37 out of 50 peptides predicted to bind HLA-A2. Among these, 36 epitopes were previously undescribed. The allorestricted T cells were exquisitely peptide- and HLA-specific and responded strongly to HLA-A2-positive leukemic cells with endogenous expression of CD20 or myeloperoxidase. These results indicate that the repertoire of self-peptides presented on HLA class I has been underestimated and that a wealth of self-TAA can be targeted by T cells when using nontolerized T-cell repertoires.
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9
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Targeting apoptosis to induce stable mixed hematopoietic chimerism and long-term allograft survival without myelosuppressive conditioning in mice. Blood 2013; 122:1669-77. [PMID: 23869083 DOI: 10.1182/blood-2012-09-453944] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Induction of mixed hematopoietic chimerism results in donor-specific immunological tolerance by apoptosis-mediated deletion of donor-reactive lymphocytes. A broad clinical application of this approach is currently hampered by limited predictability and toxicity of the available conditioning protocols. We developed a new therapeutic approach to induce mixed chimerism and tolerance by a direct pharmacological modulation of the intrinsic apoptosis pathway in peripheral T cells. The proapoptotic small-molecule Bcl-2 inhibitor ABT-737 promoted mixed chimerism induction and reversed the antitolerogenic effect of calcineurin inhibitors by boosting the critical role of the proapoptotic Bcl-2 factor Bim. A short conditioning protocol with ABT-737 in combination with costimulation blockade and low-dose cyclosporine A resulted in a complete deletion of peripheral donor-reactive lymphocytes and was sufficient to induce mixed chimerism and robust systemic tolerance across full major histocompatibility complex barriers, without myelosuppression and by using moderate doses of bone marrow cells. Thus, immunological tolerance can be achieved by direct modulation of the intrinsic apoptosis pathway in peripheral lymphocytes-a new approach to translate immunological tolerance into clinically applicable protocols.
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10
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Cippà PE, Kraus AK, Lindenmeyer MT, Chen J, Guimezanes A, Bardwell PD, Wekerle T, Wüthrich RP, Fehr T. Resistance to ABT-737 in activated T lymphocytes: molecular mechanisms and reversibility by inhibition of the calcineurin-NFAT pathway. Cell Death Dis 2012; 3:e299. [PMID: 22513873 PMCID: PMC3358016 DOI: 10.1038/cddis.2012.38] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Dynamic regulation of the intrinsic apoptosis pathway controls central and peripheral lymphocyte deletion, and may interfere with the pro-apoptotic potency of B-cell lymphoma 2 inhibitors such as ABT-737. By following a T-cell receptor (TCR) transgenic population of alloantigen-specific T cells, we found that sensitivity to ABT-737 radically changed during the course of allo-specific immune responses. Particularly, activated T cells were fully resistant to ABT-737 during the first days after antigen recognition. This phenomenon was caused by a TCR–calcineurin–nuclear factor of activated T cells-dependent upregulation of A1, and was therefore prevented by cyclosporine A (CsA). As a result, exposure to ABT-737 after alloantigen recognition induced selection of alloreactive T cells in vivo, whereas in combination with low-dose CsA, ABT-737 efficiently depleted alloreactive T cells in murine host-versus-graft and graft-versus-host models. Thus, ABT-737 resistance is not a prerogative of neoplastic cells, but it physiologically occurs in T cells after antigen recognition. Reversibility of this process by calcineurin inhibitors opens new pharmacological opportunities to modulate this process in the context of cancer, autoimmunity and transplantation.
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Affiliation(s)
- P E Cippà
- Institute of Physiology, University of Zürich, Zürich, Switzerland
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11
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Puech PH, Nevoltris D, Robert P, Limozin L, Boyer C, Bongrand P. Force measurements of TCR/pMHC recognition at T cell surface. PLoS One 2011; 6:e22344. [PMID: 21799834 PMCID: PMC3142151 DOI: 10.1371/journal.pone.0022344] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Accepted: 06/25/2011] [Indexed: 01/07/2023] Open
Abstract
The rupture forces and adhesion frequencies of single recognition complexes between an affinity selected peptide/MHC complex and a TCR at a murine hybridoma surface were measured using Atomic Force Microscopy. When the CD8 coreceptor is absent, the adhesion frequency depends on the nature of the peptide but the rupture force does not. When CD8 is present, no effect of the nature of the peptide is observed. CD8 is proposed to act as a time and distance lock, enabling the shorter TCR molecule to bridge the pMHC and have time to finely read the peptide. Ultimately, such experiments could help the dissection of the sequential steps by which the TCR reads the peptide/MHC complex in order to control T cell activation.
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Affiliation(s)
- Pierre-Henri Puech
- Laboratoire Adhésion et Inflammation, Parc Scientifique et Technologique de Luminy, Marseille, France.
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12
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Scifo C, Mekaelian L, Munyazesa E, Schmitt-Verhulst AM, Guimezanes A. Selection of T-cell receptors with a recurrent CDR3β peptide-contact motif within the repertoire of alloreactive CD8(+) T cells. Eur J Immunol 2011; 41:2414-23. [PMID: 21590766 DOI: 10.1002/eji.201141494] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 04/28/2011] [Accepted: 05/10/2011] [Indexed: 11/06/2022]
Abstract
Peptide/MHC complexes recognized by alloreactive T lymphocytes (TLs) have been identified, but their contribution to in vivo allo-rejection is not known. We previously characterized the peptide pBM1, highly represented among endogenous H-2K(b) (K(b) )-associated peptides and critically required to induce full activation of H-2(k) monoclonal CD8(+) TLs expressing the cognate TCR-BM3.3. Here, we asked whether a pBM1/K(b) -specific TL subset could be detected within a polyclonal TL population rejecting allogeneic cells in vivo. We show that the proportion of pBM1/K(b) -binding CD8(+) TLs increased from <0.04% in naïve mice to 3% of activated CD44(+) CD8(+) TLs in H-2(k) mice rejecting K(b) -expressing cells. Among these, TCR-Vβ2 usage was greatly enriched, and 75% of them shared a TCR-Vβ2 CDR3β motif with the prototype TCR-BM3.3. Fewer than 5% of K(b) -reactive CD44(+) CD8(+) TLs not binding pBM1/K(b) displayed this CDR3β motif. We found that the recurrent CDR3β motif of pBM1/K(b) -binding TLs was assembled from distinct V/D/J recombination events, suggesting that it is recruited upon immunization for its optimal TCR-peptide/MHC fit. Thus, a CDR3β motif generated by a process akin to "convergent recombination" accounts for a sizable fraction of the alloreactive anti-K(b) TCR repertoire.
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Affiliation(s)
- Caroline Scifo
- Centre d'Immunologie de Marseille-Luminy, Université de la Méditerranée, Marseille, France
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13
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Cippà PE, Kraus AK, Edenhofer I, Segerer S, Chen J, Hausmann M, Liu Y, Guimezanes A, Bardwell PD, Wüthrich RP, Fehr T. The BH3-mimetic ABT-737 inhibits allogeneic immune responses. Transpl Int 2011; 24:722-32. [DOI: 10.1111/j.1432-2277.2011.01272.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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14
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Abstract
Our goal is to provide a perspective on current understanding of the origins of specificity in immune reactions, a topic that has intrigued scientists for over a century. A fundamental property of adaptive immune responses is the ability to discriminate among an immense variety of substances by means of antibodies (Abs) and Ab-like receptors on T lymphocytes [T-cell receptors (TCRs)], each able to bind a particular chemical structure [the antigen (Ag)] and not, or only weakly, similar alternatives. Evidence has long existed, however, and has grown, especially recently, that while exhibiting remarkable specificity, many individual Abs and TCRs can also bind a variety of very different ligands. How can Ag recognition by these receptors exercise the great specificity for which they are renowned and yet react with a variety of different ligands (degeneracy)? We critically consider the mechanistic bases for this specificity/degeneracy enigma and also compare and contrast Ag recognition by Abs and TCRs.
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15
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Targeting B cell leukemia with highly specific allogeneic T cells with a public recognition motif. Leukemia 2010; 24:1901-9. [DOI: 10.1038/leu.2010.186] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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16
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Archbold JK, Macdonald WA, Burrows SR, Rossjohn J, McCluskey J. T-cell allorecognition: a case of mistaken identity or déjà vu? Trends Immunol 2008; 29:220-6. [PMID: 18378495 DOI: 10.1016/j.it.2008.02.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2007] [Revised: 02/07/2008] [Accepted: 02/07/2008] [Indexed: 02/08/2023]
Abstract
T cells bearing alphabeta T-cell receptors (TCRs) are selected by a subset of peptide-laden major histocompatibility (pMHC) molecules in the thymus and in the periphery and therefore are restricted to recognising host or 'self' MHC molecules. Nevertheless, T cells are inherently cross-reactive and often react with 'foreign' allogeneic MHC molecules (direct T-cell alloreactivity), manifested clinically as organ transplant rejection. Although the basis of T-cell alloreactivity has remained a puzzle to immunologists for decades, studies on alloreactive TCRs have begun to shed light on the basic mechanisms underpinning this 'mistaken identity'. Here we review recent advances in the field, focusing on structural and cellular studies, showing that alloreactivity may sometimes result from cross-reactivity without molecular mimicry and at other times may result directly from TCR interactions with allogeneic pMHC surfaces that mimic the cognate ligand.
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Affiliation(s)
- Julia K Archbold
- Protein Crystallography Unit, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
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18
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McNicol AM, Bendle G, Holler A, Matjeka T, Dalton E, Rettig L, Zamoyska R, Uckert W, Xue SA, Stauss HJ. CD8alpha/alpha homodimers fail to function as co-receptor for a CD8-dependent TCR. Eur J Immunol 2007; 37:1634-41. [PMID: 17506031 DOI: 10.1002/eji.200636900] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In this study, we have started to dissect the molecular basis of CD8 dependence of a high and low avidity CTL clone specific for the same peptide epitope. Using anti-CD8alpha and anti-CD8beta antibodies, we found that cytotoxicity and IFN-gamma production by high but not by low avidity CTL was strongly CD8 dependent. We isolated the TCR genes of both types of CTL clones and used retroviral gene transfer to analyse the function of these TCR in primary T cells of wild-type and CD8beta-deficient mice. Both TCR triggered antigen-specific killing in wild-type T cells, and blocking experiments showed that CD8 dependence/independence co-transferred with the TCR into primary T cells, indicating that it was dictated by the TCR itself. Gene transfer experiments into CD8beta-deficient T cells revealed that only the TCR derived from the CD8-independent CTL clone elicited antigen-specific cytotoxicity, while the CD8-dependent TCR was non-functional in the absence of the CD8beta-chain. These data indicate a striking difference between CD8alpha/beta heterodimers and CD8alpha/alpha homodimers as only the former were able to provide co-receptor function for the CD8-dependent TCR.
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MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/pharmacology
- CD3 Complex/immunology
- CD8 Antigens/genetics
- CD8 Antigens/immunology
- Cell Line, Tumor
- Cytotoxicity, Immunologic/drug effects
- Cytotoxicity, Immunologic/immunology
- Interferon-gamma/metabolism
- Interleukin-4/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Peptides/immunology
- Protein Subunits/immunology
- Protein Subunits/metabolism
- Proto-Oncogene Proteins c-mdm2/immunology
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell/metabolism
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Spleen/cytology
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/metabolism
- Transfection
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Affiliation(s)
- Anne-Marie McNicol
- Department of Immunology and Molecular Pathology, University College London, London, UK
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19
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Felix NJ, Donermeyer DL, Horvath S, Walters JJ, Gross ML, Suri A, Allen PM. Alloreactive T cells respond specifically to multiple distinct peptide-MHC complexes. Nat Immunol 2007; 8:388-97. [PMID: 17322886 DOI: 10.1038/ni1446] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2006] [Accepted: 01/31/2007] [Indexed: 01/07/2023]
Abstract
The molecular basis underlying the specificity of alloreactive T cells for peptide-major histocompatibility complex ligands has been elusive. Here we describe a screen of 60 I-E(k)-alloreactive T cells and 83 naturally processed peptides that identified 9 reactive T cells. Three of the T cells responded to multiple, distinct peptides that shared no sequence homology. These T cells recognized each peptide-major histocompatibility complex ligand specifically and used a distinct constellation of I-E(k) contact residues for each interaction. Our studies show that alloreactive T cells have a 'germline-encoded' capacity to recognize multiple, distinct ligands and thus show 'polyspecificity', not degeneracy. Our findings help to explain the high frequency of alloreactive T cells and provide insight into the nature of T cell specificity.
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Affiliation(s)
- Nathan J Felix
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63130, USA
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20
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Verdeil G, Chaix J, Schmitt-Verhulst AM, Auphan-Anezin N. Temporal cross-talk between TCR and STAT signals for CD8 T cell effector differentiation. Eur J Immunol 2007; 36:3090-100. [PMID: 17111352 DOI: 10.1002/eji.200636347] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The strength and duration of signaling through surface receptors is a primary means of controlling cell fate decisions. In adaptive immunity, Ag-initiated T cell stimulation is secondarily regulated by cytokines. We here summarize evidence for temporal control of a gene expression program in naive CD8 T cells. It is initiated in response to TCR engagement but relies on secondary signaling from cytokine receptors to be sustained and to allow development of full effector capacity. This mechanism permits cytokine receptor signaling to rescue abortive TCR signaling, such as that induced in response to weak or partial TCR agonists. Indeed, limiting TCR-initiated signaling on the Ras/ERK pathway may be complemented by STAT activation. Thus, TCR- and cytokine-driven activation of transcription factors and epigenetic modifications may act in concert in a temporally staggered process to establish the functional program of effector CD8 T cells. Based on gene expression profiling, molecular targets whose activation or inactivation may boost or dampen CD8 T cell effectors are also identified. Manipulation of these targets may, respectively, increase anti-tumor responses or prevent graft-versus-host reactions.
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Affiliation(s)
- Grégory Verdeil
- Centre d'Immunologie de Marseille-Luminy, INSERM U631, CNRS UMR 6102, Université de la Méditerranée, Marseille, France
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21
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Engelhard VH. The contributions of mass spectrometry to understanding of immune recognition by T lymphocytes. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2007; 259:32-39. [PMID: 18167512 PMCID: PMC1920184 DOI: 10.1016/j.ijms.2006.08.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Over the last 15 years, the ability of mass spectrometry to analyze complex peptide mixtures and identify individual species has provided unprecedented insights into the repertoire of peptide antigens displayed by MHC molecules and recognized by T lymphocytes. These include: understanding the peptide binding specificity of MHC molecules; understanding of roles of different intracellular components of the antigen processing pathways in determining the peptide display; and identification of a large number of individual peptide antigens associated with infectious diseases, cancer, and transplant rejection that have provided the basis for new immunologically based therapies. This review will summarize the impact that the application of mass spectrometry has had on these advances, with particular attention to the contributions of Professor Donald Hunt and members of his laboratory, and point out the opportunities for future work.
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Affiliation(s)
- Victor H Engelhard
- Carter Immunology Center and Department of Microbiology, University of Virginia School of Medicine, PO Box 801386, Charlottesville, VA USA 22908
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22
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Reibke R, Garbi N, Ganss R, Hämmerling GJ, Arnold B, Oelert T. CD8+ regulatory T cells generated by neonatal recognition of peripheral self-antigen. Proc Natl Acad Sci U S A 2006; 103:15142-7. [PMID: 17008409 PMCID: PMC1622790 DOI: 10.1073/pnas.0602622103] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2006] [Indexed: 02/03/2023] Open
Abstract
In comparison with CD4+ regulatory T cells, the generation and function of immunomodulatory CD8+T cells is less well defined. Here we describe the existence of regulatory anti-Kb-specific CD8+ T cells that are rendered tolerant during neonatal life via antigen contact exclusively on keratinocytes. These regulatory T cells maintain tolerance during adulthood as they prevent Kb-specific graft rejection by naïve CD8+ T cells. Third-party immune responses remain unaffected. Up-regulation of TGF-beta1 and granzyme B in the regulatory CD8+ T cell population suggests the involvement of these molecules in common suppressive pathways shared with CD4+ regulatory T cells. In summary, CD8+ regulatory T cells can be induced extrathymically through antigen contact on neonatally accessible parenchymal cells and maintain tolerance throughout adult life.
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Affiliation(s)
- Roland Reibke
- *Division of Molecular Immunology (D050), German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany; and
| | - Natalio Garbi
- *Division of Molecular Immunology (D050), German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany; and
| | - Ruth Ganss
- *Division of Molecular Immunology (D050), German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany; and
- Laboratory for Cancer Medicine, Western Australian Institute for Medical Research, University of Western Australia, Perth WA 6000, Australia
| | - Günter J. Hämmerling
- *Division of Molecular Immunology (D050), German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany; and
| | - Bernd Arnold
- *Division of Molecular Immunology (D050), German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany; and
| | - Thilo Oelert
- *Division of Molecular Immunology (D050), German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany; and
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23
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Auphan-Anezin N, Mazza C, Guimezanes A, Barrett-Wilt GA, Montero-Julian F, Roussel A, Hunt DF, Malissen B, Schmitt-Verhulst AM. Distinct orientation of the alloreactive monoclonal CD8 T cell activation program by three different peptide/MHC complexes. Eur J Immunol 2006; 36:1856-66. [PMID: 16761314 DOI: 10.1002/eji.200635895] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We have characterized three different programs of activation for alloreactive CD8 T cells expressing the BM3.3 TCR, their elicitation depending on the characteristics of the stimulating peptide/MHC complex. The high-affinity interaction between the TCR and the K(b)-associated endogenous peptide pBM1 (INFDFNTI) induced a complete differentiation program into effector cells correlated with sustained ERK activation. The K(bm8) variant elicited a partial activation program with delayed T cell proliferation, poor CTL activity and undetectable ERK phosphorylation; this resulted from a low-avidity interaction of TCR BM3.3 with a newly identified endogenous peptide, pBM8 (SQYYYNSL). Interestingly, mismatched pBM1/K(bm8) complexes induced a split response in BM3.3 T cells, with total reconstitution of T cell proliferation but defective generation of CTL activity that was correlated with strong but shortened ERK phosphorylation. Crystal structures highlight the molecular basis for the higher stability of pBM8/K(bm8) compared to pBM1/K(bm8) complexes that exist in two conformers. This study illustrates the importance of the stability of both peptide/MHC and peptide/MHC-TCR interactions for induction of sustained signaling required to induce optimal CTL effector functions. Subtle allelic structural variations, amplified by peptide selection, may thus orient distinct outcomes of alloreactive TCR-based therapies.
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Affiliation(s)
- Nathalie Auphan-Anezin
- Centre d'Immunologie de Marseille-Luminy, CNRS-INSERM-Universite de la Méditerranée, Campus de Luminy, Marseille, France.
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24
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Abstract
Since the first crystal structure determinations of alphabeta T cell receptors (TCRs) bound to class I MHC-peptide (pMHC) antigens in 1996, a sizable database of 24 class I and class II TCR/pMHC complexes has been accumulated that now defines a substantial degree of structural variability in TCR/pMHC recognition. Recent determination of free and bound gammadelta TCR structures has enabled comparisons of the modes of antigen recognition by alphabeta and gammadelta T cells and antibodies. Crystal structures of TCR accessory (CD4, CD8) and coreceptor molecules (CD3epsilondelta, CD3epsilongamma) have further advanced our structural understanding of most of the components that constitute the TCR signaling complex. Despite all these efforts, the structural basis for MHC restriction and signaling remains elusive as no structural features that define a common binding mode or signaling mechanism have yet been gleaned from the current set of TCR/pMHC complexes. Notwithstanding, the impressive array of self, foreign (microbial), and autoimmune TCR complexes have uncovered the diverse ways in which antigens can be specifically recognized by TCRs.
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Affiliation(s)
- Markus G Rudolph
- Department of Molecular Structural Biology, University of Göttingen, 37077 Göttingen, Germany.
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25
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Felix NJ, Suri A, Walters JJ, Horvath S, Gross ML, Allen PM. I-Ep-Bound Self-Peptides: Identification, Characterization, and Role in Alloreactivity. THE JOURNAL OF IMMUNOLOGY 2006; 176:1062-71. [PMID: 16393994 DOI: 10.4049/jimmunol.176.2.1062] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
T cell recognition of peptide/allogeneic MHC complexes is a major cause of transplant rejection. Both the presented self-peptides and the MHC molecules are involved; however, the molecular basis for alloreactivity and the contribution of self-peptides are still poorly defined. The murine 2.102 T cell is specific for hemoglobin(64-76)/I-Ek and is alloreactive to I-Ep. The natural self-peptide/I-Ep complex recognized by 2.102 remains unknown. In this study, we characterized the peptides that are naturally processed and presented by I-Ep and used this information to define the binding motif for the murine I-Ep class II molecule. Interestingly, we found that the P9 anchor residue preferred by I-Ep is quite distinct from the residues preferred by other I-E molecules, although the P1 anchor residue is conserved. A degree of specificity for the alloresponse was shown by the lack of stimulation of 2.102 T cells by 19 different identified self-peptides. The binding motif was used to search the mouse genome for candidate 2.102 reactive allopeptides that contain strong P1 and P9 anchor residues and possess previously identified allowable TCR contact residues. Two potential allopeptides were identified, but only one of these peptides, G protein-coupled receptor 128, was able to stimulate 2.102 T cells. Thus, the G protein-coupled receptor 128 peptide represents a candidate allopeptide that is specifically recognized by 2.102 T cells bound to I-Ep and was identified using bioinformatics. These studies highlight the specific involvement of self-peptides in alloreactivity.
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Affiliation(s)
- Nathan J Felix
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
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26
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Santori FR, Holmberg K, Ostrov D, Gascoigne NRJ, Vukmanović S. Distinct footprints of TCR engagement with highly homologous ligands. THE JOURNAL OF IMMUNOLOGY 2004; 172:7466-75. [PMID: 15187125 DOI: 10.4049/jimmunol.172.12.7466] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
T cell receptor engagement promotes proliferation, differentiation, survival, or death of T lymphocytes. The affinity/avidity of the TCR ligand and the maturational stage of the T cell are thought to be principal determinants of the outcome of TCR engagement. We demonstrate in this study that the same mouse TCR preferentially uses distinct residues of homologous peptides presented by the MHC molecules to promote specific cellular responses. The preference for distinct TCR contacts depends on neither the affinity/avidity of TCR engagement (except in the most extreme ranges), nor the maturity of engaged T cells. Thus, different portions of the TCR ligand appear capable of biasing T cells toward specific biological responses. These findings explain differences in functional versatility of TCR ligands, as well as anomalies in the relationship between affinity/avidity of the TCR for the peptide/MHC and cellular responses of T cells.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigen Presentation
- Epitope Mapping
- Epitopes, T-Lymphocyte/chemistry
- Epitopes, T-Lymphocyte/physiology
- Ligands
- Mice
- Mice, Transgenic
- Models, Molecular
- Peptides/chemical synthesis
- Peptides/immunology
- Protein Binding
- Protein Footprinting
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/metabolism
- Receptors, Antigen, T-Cell/physiology
- Structure-Activity Relationship
- T-Lymphocyte Subsets
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Affiliation(s)
- Fabio R Santori
- Michael Heidelberger Division of Immunology, Department of Pathology and New York University Cancer Center, New York University School of Medicine, New York, NY 10016, USA
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27
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Crawford F, Huseby E, White J, Marrack P, Kappler JW. Mimotopes for alloreactive and conventional T cells in a peptide-MHC display library. PLoS Biol 2004; 2:E90. [PMID: 15094798 PMCID: PMC387264 DOI: 10.1371/journal.pbio.0020090] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2003] [Accepted: 01/21/2004] [Indexed: 12/29/2022] Open
Abstract
The use of peptide libraries for the identification and characterization of T cell antigen peptide epitopes and mimotopes has been hampered by the need to form complexes between the peptides and an appropriate MHC molecule in order to construct a complete T cell ligand. We have developed a baculovirus-based peptide library method in which the sequence encoding the peptide is embedded within the genes for the MHC molecule in the viral DNA, such that insect cells infected with virus encoding a library of different peptides each displays a unique peptide-MHC complex on its surface. We have fished in such a library with two different fluorescent soluble T cell receptors (TCRs), one highly peptide specific and the other broadly allo-MHC specific and hypothesized to be much less focused on the peptide portion of the ligand. A single peptide sequence was selected by the former alphabetaTCR that, not unexpectedly, was highly related to the immunizing peptide. As hypothesized, the other alphabetaTCR selected a large family of peptides, related only by a similarity to the immunizing peptide at the p5 position. These findings have implications for the relative importance of peptide and MHC in TCR ligand recognition. This display method has broad applications in T cell epitope identification and manipulation and should be useful in general in studying interactions between complex proteins.
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Affiliation(s)
- Frances Crawford
- 1Howard Hughes Medical Institute, Integrated Department of ImmunologyNational Jewish Medical and Research Center, Denver, ColoradoUnited States of America
- 2Integrated Department of Immunology, University of Colorado Health Science CenterDenver, ColoradoUnited States of America
| | - Eric Huseby
- 1Howard Hughes Medical Institute, Integrated Department of ImmunologyNational Jewish Medical and Research Center, Denver, ColoradoUnited States of America
- 2Integrated Department of Immunology, University of Colorado Health Science CenterDenver, ColoradoUnited States of America
| | - Janice White
- 1Howard Hughes Medical Institute, Integrated Department of ImmunologyNational Jewish Medical and Research Center, Denver, ColoradoUnited States of America
| | - Philippa Marrack
- 1Howard Hughes Medical Institute, Integrated Department of ImmunologyNational Jewish Medical and Research Center, Denver, ColoradoUnited States of America
- 2Integrated Department of Immunology, University of Colorado Health Science CenterDenver, ColoradoUnited States of America
- 3Department of Biochemistry and Molecular Genetics, University of Colorado Health Science CenterDenver, ColoradoUnited States of America
| | - John W Kappler
- 1Howard Hughes Medical Institute, Integrated Department of ImmunologyNational Jewish Medical and Research Center, Denver, ColoradoUnited States of America
- 2Integrated Department of Immunology, University of Colorado Health Science CenterDenver, ColoradoUnited States of America
- 4Department of Pharmacology and the Program in Biomolecular Structure, University of Colorado Health Science CenterDenver, ColoradoUnited States of America
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28
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Purcell AW, Gorman JJ. Immunoproteomics: Mass spectrometry-based methods to study the targets of the immune response. Mol Cell Proteomics 2004; 3:193-208. [PMID: 14718575 DOI: 10.1074/mcp.r300013-mcp200] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The mammalian immune system has evolved to display fragments of protein antigens derived from microbial pathogens to immune effector cells. These fragments are typically peptides liberated from the intact antigens through distinct proteolytic mechanisms that are subsequently transported to the cell surface bound to chaperone-like receptors known as major histocompatibility complex (MHC) molecules. These complexes are then scrutinized by effector T cells that express clonally distributed T cell receptors with specificity for specific MHC-peptide complexes. In normal uninfected cells, this process of antigen processing and presentation occurs continuously, with the resultant array of self-antigen-derived peptides displayed on the surface of these cells. Changes in this peptide landscape of cells act to alert immune effector cells to changes in the intracellular environment that may be associated with infection, malignant transformation, or other abnormal cellular processes, resulting in a cascade of events that result in their elimination. Because peptides play such a crucial role in informing the immune system of infection with viral or microbial pathogens and the transformation of cells in malignancy, the tools of proteomics, in particular mass spectrometry, are ideally suited to study these immune responses at a molecular level. Here we review recent advances in the studies of immune responses that have utilized mass spectrometry and associated technologies, with specific examples from collaboration between our laboratories.
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Affiliation(s)
- A W Purcell
- Department of Microbiology and Immunology and ImmunoID, The University of Melbourne, Victoria 3010, Australia.
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29
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Randriamampita C, Delon J, Trautmann A. Response to Davis and van der Merwe: No model fully explains how TCR signaling begins. Trends Immunol 2003. [DOI: 10.1016/j.it.2003.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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30
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Buslepp J, Wang H, Biddison WE, Appella E, Collins EJ. A Correlation between TCR Vα Docking on MHC and CD8 Dependence. Immunity 2003; 19:595-606. [PMID: 14563323 DOI: 10.1016/s1074-7613(03)00269-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
T cell receptors (TCR) adopt a similar orientation when binding with major histocompatibility complex (MHC) molecules, yet the biological mechanism that generates this similar TCR orientation remains obscure. We show here the cocrystallographic structure of a mouse TCR bound to a human MHC molecule not seen by the TCR during thymic development. The orientation of this xenoreactive murine TCR atop human MHC deviates from the typical orientation more than any previously determined TCR/MHC structure. This unique orientation is solely due to the placement of the TCR Valpha domain on the MHC. In light of new information provided by this structure, we have reanalyzed the existing TCR/MHC cocrystal structures and discovered unique features of TCR Valpha domain position on class I MHC that correlate with CD8 dependence. Finally, we propose that the orientation seen in TCR recognition of MHC is a consequence of selection during T cell development.
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Affiliation(s)
- Jennifer Buslepp
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA
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31
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Affiliation(s)
- Bernard Malissen
- Centre d'Immunologie de Marseille-Luminy, INSERM-CNRS-Université de la Méditerranée, Parc Scientifique de Luminy, Case 906, 13288 Marseille Cedex 9, France
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32
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Housset D, Malissen B. What do TCR-pMHC crystal structures teach us about MHC restriction and alloreactivity? Trends Immunol 2003; 24:429-37. [PMID: 12909456 DOI: 10.1016/s1471-4906(03)00180-7] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Dominique Housset
- Laboratoire de Cristallographie et Cristallogénèse des Protéines, Institut de Biologie Structurale J.-P. Ebel, CEA-CNRS-UJF, 41 rue Jules Horowitz, F-38027 Grenoble Cedex 1, France
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33
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Reiser JB, Darnault C, Grégoire C, Mosser T, Mazza G, Kearney A, van der Merwe PA, Fontecilla-Camps JC, Housset D, Malissen B. CDR3 loop flexibility contributes to the degeneracy of TCR recognition. Nat Immunol 2003; 4:241-7. [PMID: 12563259 DOI: 10.1038/ni891] [Citation(s) in RCA: 203] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2002] [Accepted: 01/08/2003] [Indexed: 11/09/2022]
Abstract
T cell receptor (TCR) binding degeneracy lies at the heart of several physiological and pathological phenomena, yet its structural basis is poorly understood. We determined the crystal structure of a complex involving the BM3.3 TCR and an octapeptide (VSV8) bound to the H-2K(b) major histocompatibility complex molecule at a 2.7 A resolution, and compared it with the BM3.3 TCR bound to the H-2K(b) molecule loaded with a peptide that has no primary sequence identity with VSV8. Comparison of these structures showed that the BM3.3 TCR complementarity-determining region (CDR) 3alpha could undergo rearrangements to adapt to structurally different peptide residues. Therefore, CDR3 loop flexibility helps explain TCR binding cross-reactivity.
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Affiliation(s)
- Jean-Baptiste Reiser
- Laboratoire de Cristallographie et Cristallogenèse des Protéines, Institut de Biologie Structurale J.-P. Ebel, CEA-CNRS-UJF, 41 rue Jules Horowitz, F-38027 Grenoble Cedex 1, France
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34
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Holler PD, Kranz DM. Quantitative analysis of the contribution of TCR/pepMHC affinity and CD8 to T cell activation. Immunity 2003; 18:255-64. [PMID: 12594952 DOI: 10.1016/s1074-7613(03)00019-0] [Citation(s) in RCA: 286] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The relative roles of CD8, TCR:pepMHC affinity, and TCR:pepMHC dissociation rate in T cell activation have remained controversial. To determine the relationships among these factors, we used T cells transfected with normal and in vitro engineered alphabeta TCRs, in the presence or absence of CD8. The TCRs exhibited a wide range of affinities (K(D) values of 80 microM to 5 nM). T cells with the highest affinity TCRs were efficiently stimulated by peptide, with or without CD8. In contrast, CD8 was required for T cells that expressed TCRs with affinities typical of syngeneic reactions (K(D) values above approximately 3 microM). The results suggest that virtually all normal syngeneic interactions require CD8, which enhances peptide sensitivity by one million-fold or more.
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Affiliation(s)
- Phillip D Holler
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
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35
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Sacher T, Knolle P, Nichterlein T, Arnold B, Hämmerling GJ, Limmer A. CpG-ODN-induced inflammation is sufficient to cause T-cell-mediated autoaggression against hepatocytes. Eur J Immunol 2002; 32:3628-37. [PMID: 12516551 DOI: 10.1002/1521-4141(200212)32:12<3628::aid-immu3628>3.0.co;2-e] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Autoimmune diseases are often associated with microbial infections. Molecular mimicry between microbial antigens and self-epitopes has been suggested as a mechanism for breaking self-tolerance and induction of autoimmunity. Since infections also cause inflammatory responses we explored the role of local inflammation in organ-specific autoimmunity. For this purpose, transgenic mice were used expressing the MHC class I molecule Kb exclusively on hepatocytes. These mice exhibit Kb-specific tolerance as exemplified by the acceptance of Kb+ grafts. Inflammatory reactions were induced by injection of immunostimulatory cytosine-phosphorothioate-guanine (CpG)-rich oligodeoxynucleotides (ODN). Application of CpG-ODN is sufficient to break tolerance in vivo, and to cause activation of Kb-specific CD8+ T cells and subsequent autoaggression against hepatocytes. The CpG-ODN-induced inflammation appears to have two major effects. First, it causes infiltration of T cells into the liver parenchyma. Second, adhesion and costimulatory molecules are up-regulated on hepatocytes so that the infiltrating CD8+ T cells encounter Kb on hepatocytes, which display an APC-like phenotype, resulting in activation and tissue damage. Autoimmune hepatitis can be maintained for at least eight weeks by repeated application of CpG-ODN but subsides after termination of the inflammatory stimulus, suggesting the requirement of additional factors for a self-perpetuation of autoimmunity. These observations describe an additional pathway for the induction of autoimmunity, i.e. in the absence of microbial antigens inflammatory reactions alone can lead to infiltration of T cells into organs, resulting in breaking of tolerance and autoaggression. Moreover, the results provide evidence that T cell activation can take place not only in draining lymph nodes but also directly on parenchymal cells.
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36
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Rock KL, York IA, Saric T, Goldberg AL. Protein degradation and the generation of MHC class I-presented peptides. Adv Immunol 2002; 80:1-70. [PMID: 12078479 DOI: 10.1016/s0065-2776(02)80012-8] [Citation(s) in RCA: 271] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Over the past decade there has been considerable progress in understanding how MHC class I-presented peptides are generated. The emerging theme is that the immune system has not evolved its own specialized proteolytic mechanisms but instead utilizes the phylogenetically ancient catabolic pathways that continually turnover proteins in all cells. Three distinct proteolytic steps have now been defined in MHC class I antigen presentation. The first step is the degradation of proteins by the ubiquitin-proteasome pathway into oligopeptides that either are of the correct size for presentation or are extended on their amino-termini. In the second step, aminopeptidases trim N-extended precursors into peptides of the correct length to be presented on class I molecules. The third step involves the destruction of peptides by endo- and exopeptidases, which limits antigen presentation, but is important for preventing the accumulation of peptides and recycling them back to amino acids for protein synthesis or production of energy. The immune system has evolved several components that modify the activity of these ancient pathways in ways that enhance the generation of class I-presented peptides. These include catalytically active subunits of the proteasome, the PA28 proteasome activator, and leucine aminopeptidase, all of which are upregulated by interferon-gamma. In addition to these pathways that operate in all cells, dendritic cells and macrophages can also generate class I-presented peptides from proteins internalized from the extracellular fluids by degrading them in endocytic compartments or transferring them to the cyotosol for degradation by proteasomes.
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Affiliation(s)
- Kenneth L Rock
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA
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37
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Abstract
The immune system is an adaptive defense system capable of specifically recognizing and eliminating an apparently limitless variety of foreign invaders. This highly specific response is provided by T and B lymphocytes. The enormous diversity of the antigen-specific receptors on these cells is generated by random rearrangement of the respective genes. The key challenge of such a defense system is to have as broad a T and B cell repertoire as possible in the absence of autoreactivity. This review summarizes mechanisms of peripheral T cell tolerance induction seen in various animal models. There is increasing evidence that tolerance to tissue-specific antigens can be induced by dendritic cells in the regional lymph nodes as well as by parenchymal cells like keratinocytes and hepatocytes in the respective tissues. Furthermore, tolerance induction should no longer only be viewed as prevention of T cell activation, as in certain systems activation of autoreactive T cells is insufficient to cause tissue damage. Thus, several tolerance mechanisms are operating in parallel under physiological conditions. With increasing knowledge of the molecular basis we will learn which mechanism is most suitable for therapeutic intervention.
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Affiliation(s)
- Bernd Arnold
- Molecular Immunology, Deutsches Krebsforschungszentrum DKFZ, Heidelberg, Germany.
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38
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Reiser JB, Grégoire C, Darnault C, Mosser T, Guimezanes A, Schmitt-Verhulst AM, Fontecilla-Camps JC, Mazza G, Malissen B, Housset D. A T cell receptor CDR3beta loop undergoes conformational changes of unprecedented magnitude upon binding to a peptide/MHC class I complex. Immunity 2002; 16:345-54. [PMID: 11911820 DOI: 10.1016/s1074-7613(02)00288-1] [Citation(s) in RCA: 179] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The elongated complementary-determining region (CDR) 3beta found in the unliganded KB5-C20 TCR protrudes from the antigen binding site and prevents its docking onto the peptide/MHC (pMHC) surface according to a canonical diagonal orientation. We now present the crystal structure of a complex involving the KB5-C20 TCR and an octapeptide bound to the allogeneic H-2K(b) MHC class I molecule. This structure reveals how a tremendously large CDR3beta conformational change allows the KB5-C20 TCR to adapt to the rather constrained pMHC surface and achieve a diagonal docking mode. This extreme case of induced fit also shows that TCR plasticity is primarily restricted to CDR3 loops and does not propagate away from the antigen binding site.
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Affiliation(s)
- Jean Baptiste Reiser
- Laboratoire de Cristallographie et Cristallogénèse des Protéines, Institut de Biologie Structurale J.-P. Ebel, CEA-CNRS-UJF, 41 rue Jules Horowitz, F-38027 Grenoble Cedex 1, France
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39
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Machy P, Serre K, Baillet M, Leserman L. Induction of MHC class I presentation of exogenous antigen by dendritic cells is controlled by CD4+ T cells engaging class II molecules in cholesterol-rich domains. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:1172-80. [PMID: 11801652 DOI: 10.4049/jimmunol.168.3.1172] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We investigated interactions between CD4+ T cells and dendritic cells (DC) necessary for presentation of exogenous Ag by DC to CD8+ T cells. CD4+ T cells responding to their cognate Ag presented by MHC class II molecules of DC were necessary for induction of CD8+ T cell responses to MHC class I-associated Ag, but their ability to do so depended on the manner in which class II-peptide complexes were formed. DC derived from short-term mouse bone marrow culture efficiently took up Ag encapsulated in IgG FcR-targeted liposomes and stimulated CD4+ T cell responses to Ag-derived peptides associated with class II molecules. This CD4+ T cell-DC interaction resulted in expression by the DC of complexes of class I molecules and peptides from the Ag delivered in liposomes and permitted expression of the activation marker CD69 and cytotoxic responses by naive CD8+ T cells. However, while free peptides in solution loaded onto DC class II molecules could stimulate IL-2 production by CD4+ T cells as efficiently as peptides derived from endocytosed Ag, they could not stimulate induction of cytotoxic responses by CD8+ T cells to Ag delivered in liposomes into the same DC. Signals requiring class II molecules loaded with endocytosed Ag, but not free peptide, were inhibited by methyl-beta-cyclodextrin, which depletes cell membrane cholesterol. CD4+ T cell signals thus require class II molecules in cholesterol-rich domains of DC for induction of CD8+ T cell responses to exogenous Ag by inducing DC to process this Ag for class I presentation.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 2
- ATP-Binding Cassette Transporters/metabolism
- Animals
- Antigen Presentation/drug effects
- CD4-Positive T-Lymphocytes/drug effects
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- Cells, Cultured
- Cholesterol/immunology
- Cholesterol/metabolism
- Cyclodextrins/pharmacology
- Cysteine Endopeptidases/metabolism
- Cytoplasm/immunology
- Cytoplasm/metabolism
- Dendritic Cells/drug effects
- Dendritic Cells/immunology
- Dendritic Cells/metabolism
- Egg Proteins/biosynthesis
- Egg Proteins/immunology
- Endocytosis/drug effects
- Endocytosis/immunology
- H-2 Antigens/biosynthesis
- H-2 Antigens/metabolism
- Histocompatibility Antigens Class II/immunology
- Histocompatibility Antigens Class II/metabolism
- Immunosuppressive Agents/pharmacology
- Lymphocyte Activation/drug effects
- Membrane Lipids/antagonists & inhibitors
- Membrane Lipids/metabolism
- Membrane Microdomains/drug effects
- Membrane Microdomains/immunology
- Mice
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Mice, Transgenic
- Multienzyme Complexes/metabolism
- Ovalbumin/biosynthesis
- Ovalbumin/immunology
- Peptide Fragments
- Proteasome Endopeptidase Complex
- Protein Structure, Tertiary
- Receptors, Fc/metabolism
- T-Lymphocytes, Helper-Inducer/immunology
- Tumor Cells, Cultured
- beta-Cyclodextrins
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Affiliation(s)
- Patrick Machy
- Centre d'Immunologie de Marseille-Luminy, 13288 Marseille, Cedex 9, France
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40
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Auphan-Anezin N, Schmitt-Verhulst AM. Differential survival of transferred CD8 T cells and host reconstitution depending on TCR avidity for host-expressed alloantigen. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:7200-7. [PMID: 11390468 DOI: 10.4049/jimmunol.166.12.7200] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We transferred naive alloreactive CD8 T cells from TCR transgenic mice to irradiated recipients expressing a partial (H-2Kbm8) or a full (H-2Kb) agonist alloantigen (alloAg). The consequences were strikingly distinct, resulting in acceleration of host lymphopoiesis in the former group, but in strong graft-vs-host reaction, preventing host lymphocyte reconstitution in the latter group. This was correlated, respectively, with long-term persistence and with rapid disappearance of the transferred CD8 T cells. Analysis of transferred T cells showed that initial T cell expansion and modulation of expression of activation markers CD44 and CD62L, as well as induction of cytotoxic function, were similar in both groups. However, IL-2 production and subsequent up-regulation of CD25, early perforin-independent cytolysis, and early down-regulation of Bcl-2 expression were detected only in T cells transferred in hosts expressing full agonist alloAg. Expansion of transferred CD8 T cells was not dependent on either IL-2 or CD25 expression. This expansion could lead to either accelerated host reconstitution or to strong graft-vs-host, depending on the nature of the alloAg. Thus, the extent of Ag stimulation may be a crucial parameter in protocols of alloreactive T cell immunotherapy.
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MESH Headings
- Adoptive Transfer
- Animals
- Apoptosis/immunology
- CD8-Positive T-Lymphocytes/cytology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- CD8-Positive T-Lymphocytes/transplantation
- Cell Survival/genetics
- Cell Survival/immunology
- Cytotoxicity Tests, Immunologic
- Down-Regulation/immunology
- Graft vs Host Reaction/genetics
- Graft vs Host Reaction/immunology
- Hyaluronan Receptors/biosynthesis
- Interleukin-2/physiology
- Isoantigens/biosynthesis
- Isoantigens/metabolism
- Isoantigens/physiology
- Kinetics
- L-Selectin/biosynthesis
- Lymphocyte Activation/genetics
- Mice
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Mice, Knockout
- Mice, Transgenic
- Proto-Oncogene Proteins c-bcl-2/antagonists & inhibitors
- Proto-Oncogene Proteins c-bcl-2/biosynthesis
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Radiation Chimera/immunology
- Receptors, Antigen, T-Cell/biosynthesis
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/metabolism
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Affiliation(s)
- N Auphan-Anezin
- Centre d'Immunologie de Marseille-Luminy, Centre National de la Recherche Scientifique-Institut National de la Santé et de la Recherche Médicale-Université de la Méditerranée, Campus de Luminy, Marseille, France.
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