1
|
Hu M, Rogers NM, Li J, Zhang GY, Wang YM, Shaw K, O'Connell PJ, Alexander SI. Antigen Specific Regulatory T Cells in Kidney Transplantation and Other Tolerance Settings. Front Immunol 2021; 12:717594. [PMID: 34512640 PMCID: PMC8428972 DOI: 10.3389/fimmu.2021.717594] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/05/2021] [Indexed: 12/25/2022] Open
Abstract
Kidney transplantation is the most common solid organ transplant and the best current therapy for end-stage kidney failure. However, with standard immunosuppression, most transplants develop chronic dysfunction or fail, much of which is due to chronic immune injury. Tregs are a subset of T cells involved in limiting immune activation and preventing autoimmune disease. These cells offer the potential to provide tolerance or to allow reduction in immunosuppression in kidney transplants. The importance of Tregs in kidney transplantation has been shown in a number of seminal mouse and animal studies, including those with T cell receptors (TCRs) transgenic Tregs (TCR-Tregs) or Chimeric Antigen Receptor (CAR) Tregs (CAR-Tregs) showing that specificity increases the potency of Treg function. Here we outline the animal and human studies and clinical trials directed at using Tregs in kidney transplantation and other tolerance settings and the various modifications to enhance allo-specific Treg function in vivo and in vitro.
Collapse
Affiliation(s)
- Min Hu
- Centre for Transplant and Renal Research, Westmead Institute for Medical Research, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Natasha M Rogers
- Centre for Transplant and Renal Research, Westmead Institute for Medical Research, Sydney, NSW, Australia
| | - Jennifer Li
- Centre for Transplant and Renal Research, Westmead Institute for Medical Research, Sydney, NSW, Australia
| | - Geoff Y Zhang
- Centre for Kidney Research, Children's Hospital at Westmead, Sydney, NSW, Australia
| | - Yuan Min Wang
- Centre for Kidney Research, Children's Hospital at Westmead, Sydney, NSW, Australia
| | - Karli Shaw
- Centre for Kidney Research, Children's Hospital at Westmead, Sydney, NSW, Australia
| | - Philip J O'Connell
- Centre for Transplant and Renal Research, Westmead Institute for Medical Research, Sydney, NSW, Australia
| | - Stephen I Alexander
- Centre for Kidney Research, Children's Hospital at Westmead, Sydney, NSW, Australia
| |
Collapse
|
2
|
Regulatory Cell Therapy in Kidney Transplantation: Promise Not Yet Fulfilled. Transplantation 2020; 104:2262-2263. [PMID: 33125204 DOI: 10.1097/tp.0000000000003150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
3
|
Indirectly Activated Treg Allow Dominant Tolerance to Murine Skin-grafts Across an MHC Class I Mismatch After a Single Donor-specific Transfusion. Transplantation 2020; 104:1385-1395. [PMID: 32053573 DOI: 10.1097/tp.0000000000003173] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Tolerance induced in stringent animal transplant models using donor-specific transfusions (DST) has previously required additional immunological manipulation. Here, we demonstrate a dominant skin-allograft tolerance model induced by a single DST across an major histocompatibility class I mismatch in an unmanipulated B6 host. METHODS C57BL/6 (H-2) (B6) mice were injected intravenously with splenocytes from B6.C.H-2 (H-2k) (bm1) or F1 (B6 × bm1) mice before skin transplantation. Mice were transplanted 7 days postinjection with donor (bm1 or F1) and third-party B10.BR (H-2) skin grafts. RESULTS B6 hosts acutely rejected skin grafts from B6.C.H-2 (bm1) and F1 (B6 × bm1) mice. A single transfusion of F1 splenocytes into B6 mice without any additional immune modulation led to permanent acceptance of F1 skin grafts. This graft acceptance was associated with persistence of donor cells long-term in vivo. The more rapid removal of DST bm1 cells than F1 cells was reduced by natural killer-cell depletion. Tolerant grafts survived an in vivo challenge with naive splenocytes. Both CD4CD25 and CD4CD25 T cells from F1 DST treated B6 mice suppressed alloproliferation in vitro. Tolerance was associated with expansion of peripheral Foxp3CD4CD25 regulatory T cells (Treg) and increased forkhead box P3 (Foxp3) expression in tolerant grafts. In tolerant mice, Foxp3 Treg arises from the proliferation of indirectly activated natural Foxp3 Treg (nTreg) and depletion of Foxp3 Treg abrogates skin-graft tolerance. CONCLUSIONS This study demonstrates that the persistence of transfused semiallogeneic donor cells mismatched at major histocompatibility class I can enhance tolerance to subsequent skin allografts through indirectly expanded nTreg leading to dominant tolerance without additional immunological manipulation.
Collapse
|
4
|
Shahbazi M, Soltanzadeh-Yamchi M, Mohammadnia-Afrouzi M. T cell exhaustion implications during transplantation. Immunol Lett 2018; 202:52-58. [PMID: 30130559 DOI: 10.1016/j.imlet.2018.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 08/05/2018] [Accepted: 08/16/2018] [Indexed: 12/20/2022]
Abstract
Exhaustion of lymphocyte function, particularly T cell exhaustion, due to prolonged exposure to a high load of foreign antigen is commonly seen during chronic viral infection as well as antitumor immune responses. This phenomenon has been associated with a determined molecular mechanism and phenotypic manifestations on the cell surface. In spite of investigation of exhaustion, mostly about CD8 responses toward viral infections, recent studies have reported that chronic exposure to antigen may develop exhaustion in CD4 + T cells, B cells, and NK cells. Little is known with respect to lymphocyte exhaustion during transplantation and its effect on aberrant anti-graft responses. Through a same mechanobiology observed during chronic exposure of foreign viral antigens, alloantigen persistence mediated by allograft could develop a favorable circumstance for exhaustion of T cells responding to allograft. However, to achieve better manipulation approaches of this event to reduce the complications during transplantation, we need to be armed with a bulk of knowledge with regard to quality and quantity of T cell exhaustion occurring in various allografts, the kinetics of exhaustion development, the impression of immunosuppressive agents on the exhaustion, and the influence of exhaustion on graft survival and immune tolerance.
Collapse
Affiliation(s)
- Mehdi Shahbazi
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran; Immunoregulation Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran; Department of Immunology, School of Medicine, Babol University of Medical Sciences, Babol, Iran
| | - Mehdi Soltanzadeh-Yamchi
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran; Infectious Diseases and Tropical Medicine Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran; Department of Immunology, School of Medicine, Babol University of Medical Sciences, Babol, Iran
| | - Mousa Mohammadnia-Afrouzi
- Infectious Diseases and Tropical Medicine Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran; Immunoregulation Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran; Department of Immunology, School of Medicine, Babol University of Medical Sciences, Babol, Iran.
| |
Collapse
|
5
|
Waight JD, Chand D, Dietrich S, Gombos R, Horn T, Gonzalez AM, Manrique M, Swiech L, Morin B, Brittsan C, Tanne A, Akpeng B, Croker BA, Buell JS, Stein R, Savitsky DA, Wilson NS. Selective FcγR Co-engagement on APCs Modulates the Activity of Therapeutic Antibodies Targeting T Cell Antigens. Cancer Cell 2018; 33:1033-1047.e5. [PMID: 29894690 PMCID: PMC6292441 DOI: 10.1016/j.ccell.2018.05.005] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 04/03/2018] [Accepted: 05/09/2018] [Indexed: 02/06/2023]
Abstract
The co-engagement of fragment crystallizable (Fc) gamma receptors (FcγRs) with the Fc region of recombinant immunoglobulin monoclonal antibodies (mAbs) and its contribution to therapeutic activity has been extensively studied. For example, Fc-FcγR interactions have been shown to be important for mAb-directed effector cell activities, as well as mAb-dependent forward signaling into target cells via receptor clustering. Here we identify a function of mAbs targeting T cell-expressed antigens that involves FcγR co-engagement on antigen-presenting cells (APCs). In the case of mAbs targeting CTLA-4 and TIGIT, the interaction with FcγR on APCs enhanced antigen-specific T cell responses and tumoricidal activity. This mechanism extended to an anti-CD45RB mAb, which led to FcγR-dependent regulatory T cell expansion in mice.
Collapse
MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/metabolism
- Antibodies, Monoclonal/therapeutic use
- Antigen-Presenting Cells/immunology
- Antigen-Presenting Cells/metabolism
- Antigens, Differentiation, T-Lymphocyte/immunology
- Antigens, Differentiation, T-Lymphocyte/metabolism
- CTLA-4 Antigen/immunology
- CTLA-4 Antigen/metabolism
- Humans
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Neoplasms/drug therapy
- Neoplasms/immunology
- Neoplasms/metabolism
- Protein Binding
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell/metabolism
- Receptors, IgG/immunology
- Receptors, IgG/metabolism
- Receptors, Immunologic/immunology
- Receptors, Immunologic/metabolism
- Signal Transduction/drug effects
- Signal Transduction/immunology
- T-Lymphocytes/drug effects
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
Collapse
Affiliation(s)
| | | | - Sylvia Dietrich
- Agenus Inc., Lexington, MA 02421, USA; Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | | | | | | | | | | | | | | | | | - Ben A Croker
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | | | | | | |
Collapse
|
6
|
Pilat N, Granofszky N, Wekerle T. Combining Adoptive Treg Transfer with Bone Marrow Transplantation for Transplantation Tolerance. CURRENT TRANSPLANTATION REPORTS 2017; 4:253-261. [PMID: 29201599 PMCID: PMC5691126 DOI: 10.1007/s40472-017-0164-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW The mixed chimerism approach is an exceptionally potent strategy for the induction of donor-specific tolerance in organ transplantation and so far the only one that was demonstrated to work in the clinical setting. Regulatory T cells (Tregs) have been shown to improve chimerism induction in experimental animal models. This review summarizes the development of innovative BMT protocols using therapeutic Treg transfer for tolerance induction. RECENT FINDINGS Treg cell therapy promotes BM engraftment in reduced conditioning protocols in both, mice and non-human primates. In mice, transfer of polyclonal recipient Tregs was sufficient to substitute cytotoxic recipient conditioning. Treg therapy prevented chronic rejection of skin and heart allografts related to tissue-specific antigen disparities, in part by promoting intragraft Treg accumulation. SUMMARY Adoptive Treg transfer is remarkably effective in facilitating BM engraftment in reduced-intensity protocols in mice and non-human primates. Furthermore, it promotes regulatory mechanisms that prevent chronic rejection.
Collapse
Affiliation(s)
- Nina Pilat
- Section of Transplantation Immunology, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Nicolas Granofszky
- Section of Transplantation Immunology, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Thomas Wekerle
- Section of Transplantation Immunology, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| |
Collapse
|
7
|
Hickey MJ, Chow Z. Viewing immune regulation as it happens: in vivo imaging for investigation of regulatory T-cell function. Immunol Cell Biol 2017; 95:514-519. [PMID: 28420873 DOI: 10.1038/icb.2017.33] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 04/10/2017] [Accepted: 04/10/2017] [Indexed: 12/12/2022]
Abstract
Regulatory T cells (Tregs) play indispensable roles in the immune system, in limiting excessive or inappropriate immune and inflammatory responses. They achieve this function via effects on other immune cells in the secondary lymphoid system, and in peripheral locations such as skin, gut and bone marrow. As for the more extensively studied cellular players in the immune system, particularly dendritic cells and conventional T cells, in vivo imaging of Tregs via two-photon (or multiphoton) microscopy (MPM) has been central to the development of understanding how these cells function. In this brief review, we will describe the studies that have utilised MPM to examine Treg behaviour in vivo. These studies have investigated Treg behaviour in lymph nodes and spleen, as well as in peripheral organs such as skin, small intestine and bone marrow. The findings from these experiments underline how assumptions made about Treg function based on results of in vitro experiments are often not supported by direct visualisation of these cells in their normal in vivo settings. Together this work reveals that only via MPM analysis can Treg function be investigated in the complicated multicellular environments where conventional T cells, antigen-presenting cells and other potential cellular targets of Tregs are present with each undergoing their own specific actions.
Collapse
Affiliation(s)
- Michael J Hickey
- Centre for Inflammatory Diseases, Department of Medicine, Monash University, Monash Medical Centre, Clayton, Victoria, Australia
| | - Zachary Chow
- Centre for Inflammatory Diseases, Department of Medicine, Monash University, Monash Medical Centre, Clayton, Victoria, Australia
| |
Collapse
|
8
|
Anti‐CD45RB and donor‐specific spleen cells transfusion inhibition allograft skin rejection mediated by memory T cells. Immunol Cell Biol 2016; 95:189-197. [PMID: 27616751 DOI: 10.1038/icb.2016.88] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Revised: 08/17/2016] [Accepted: 08/29/2016] [Indexed: 01/08/2023]
|
9
|
Abstract
PURPOSE OF REVIEW The role of T-cell exhaustion in the failure of clearance of viral infections and tumors is well established. There are several ongoing trials to reverse T-cell exhaustion for treatment of chronic viral infections and tumors. The mechanisms leading to T-cell exhaustion and its role in transplantation, however, are only beginning to be appreciated and are the focus of the present review. RECENT FINDINGS Exhausted T cells exhibit a distinct molecular profile reflecting combinatorial mechanisms involving the interaction of multiple transcription factors important in control of cell metabolism, acquisition of effector function and memory capacity. Change of microenvironmental cues and limiting leukocyte recruitment can modulate T-cell exhaustion. Impaired leukocyte recruitment induces T-cell exhaustion and prevents allograft rejection. SUMMARY Preventing or reversing T-cell exhaustion may lead to prevention of transplant tolerance or triggering of rejection; therefore, caution should be exercised in the use of agents blocking inhibitory receptors for the treatment of chronic viral infections or tumors in transplant recipients. Further definition of the role of T-cell exhaustion in clinical transplantation and an understanding of the mechanisms of induction of T-cell exhaustion are needed to develop strategies for preventing allograft rejection and induction of tolerance.
Collapse
|
10
|
Camirand G, Wang Y, Lu Y, Wan YY, Lin Y, Deng S, Guz G, Perkins DL, Finn PW, Farber DL, Flavell RA, Shlomchik WD, Lakkis FG, Rudd CE, Rothstein DM. CD45 ligation expands Tregs by promoting interactions with DCs. J Clin Invest 2014; 124:4603-13. [PMID: 25202978 DOI: 10.1172/jci74087] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 08/06/2014] [Indexed: 12/13/2022] Open
Abstract
Regulatory T cells (Tregs), which express CD4 and FOXP3, are critical for modulating the immune response and promoting immune tolerance. Consequently, methods to expand Tregs for therapeutic use are of great interest. While transfer of Tregs after massive ex vivo expansion can be achieved, in vivo expansion of Tregs would be more practical. Here, we demonstrate that targeting the CD45 tyrosine phosphatase with a tolerogenic anti-CD45RB mAb acutely increases Treg numbers in WT mice, even in absence of exogenous antigen. Treg expansion occurred through substantial augmentation of homeostatic proliferation in the preexisting Treg population. Moreover, anti-CD45RB specifically increased Treg proliferation in response to cognate antigen. Compared with conventional T cells, Tregs differentially regulate their conjugation with DCs. Therefore, we determined whether CD45 ligation could alter interactions between Tregs and DCs. Live imaging showed that CD45 ligation specifically reduced Treg motility in an integrin-dependent manner, resulting in enhanced interactions between Tregs and DCs in vivo. Increased conjugate formation, in turn, augmented nuclear translocation of nuclear factor of activated T cells (NFAT) and Treg proliferation. Together, these results demonstrate that Treg peripheral homeostasis can be specifically modulated in vivo to promote Treg expansion and tolerance by increasing conjugation between Tregs and DCs.
Collapse
|
11
|
Wang H, Yang Y, Wang G, Wang S, Yeap BY, Sykes M, Yang YG. Donor bone marrow-derived T cells inhibit GVHD induced by donor lymphocyte infusion in established mixed allogeneic hematopoietic chimeras. PLoS One 2012; 7:e47120. [PMID: 23077554 PMCID: PMC3471915 DOI: 10.1371/journal.pone.0047120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 09/10/2012] [Indexed: 11/18/2022] Open
Abstract
Delayed administration of donor lymphocyte infusion (DLI) to established mixed chimeras has been shown to achieve anti-tumor responses without graft-vs.-host disease (GVHD). Herein we show that de novo donor BM-derived T cells that are tolerant of the recipients are important in preventing GVHD in mixed chimeras receiving delayed DLI. Mixed chimeras lacking donor BM-derived T cells developed significantly more severe GVHD than those with donor BM-derived T cells after DLI, even though both groups had comparable levels of total T cells at the time of DLI. Post-DLI depletion of donor BM-derived T cells in mixed chimeras, as late as 20 days after DLI, also provoked severe GVHD. Although both CD4 and CD8 T cells contributed to the protection, the latter were significantly more effective, suggesting that inhibition of GVHD was not mainly mediated by CD4 regulatory T cells. The lack of donor BM-derived T cells was associated with markedly increased accumulation of DLI-derived alloreactive T cells in parenchymal GVHD target tissues. Thus, donor BM-derived T cells are an important factor in determining the risk of GVHD and therefore, offer a potential therapeutic target for preventing and ameliorating GVHD in the setting of delayed DLI in established mixed chimeras.
Collapse
Affiliation(s)
- Hui Wang
- Columbia Center for Translational Immunology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Yanping Yang
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- First Bethune Hospital of Jilin University, Changchun, Jilin, China
| | - Guanjun Wang
- First Bethune Hospital of Jilin University, Changchun, Jilin, China
| | - Shumei Wang
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Beow Yong Yeap
- Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Megan Sykes
- Columbia Center for Translational Immunology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
| | - Yong-Guang Yang
- Columbia Center for Translational Immunology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
- First Bethune Hospital of Jilin University, Changchun, Jilin, China
- * E-mail:
| |
Collapse
|
12
|
Kim YH, Kim HJ, Kim JS, Park CG. Application of Regulatory T Cells in Transplantation Field. KOREAN JOURNAL OF TRANSPLANTATION 2012. [DOI: 10.4285/jkstn.2012.26.2.74] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Yong-Hee Kim
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Korea
- Transplantation Research Institute SNUMRC, Seoul National University College of Medicine, Seoul, Korea
- Cancer Research Institute and TIMRC, Seoul National University College of Medicine, Seoul, Korea
| | - Hyun-Je Kim
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Korea
- Transplantation Research Institute SNUMRC, Seoul National University College of Medicine, Seoul, Korea
- Cancer Research Institute and TIMRC, Seoul National University College of Medicine, Seoul, Korea
| | - Jung-Sik Kim
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Korea
- Transplantation Research Institute SNUMRC, Seoul National University College of Medicine, Seoul, Korea
- Cancer Research Institute and TIMRC, Seoul National University College of Medicine, Seoul, Korea
| | - Chung-Gyu Park
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Korea
- Xenotransplantation Research Center, Seoul National University College of Medicine, Seoul, Korea
- Transplantation Research Institute SNUMRC, Seoul National University College of Medicine, Seoul, Korea
- Cancer Research Institute and TIMRC, Seoul National University College of Medicine, Seoul, Korea
| |
Collapse
|
13
|
Abstract
Regulatory T cells (Tregs) are long-lived cells that suppress immune responses in vivo in a dominant and antigen-specific manner. Therefore, therapeutic application of Tregs to control unwanted immune responses is an active area of investigation. Tregs can confer long-term protection against auto-inflammatory diseases in mouse models. They have also been shown to be effective in suppressing alloimmunity in models of graft-versus-host disease and organ transplantation. Building on extensive research in Treg biology and preclinical testing of therapeutic efficacy over the past decade, we are now at the point of evaluating the safety and efficacy of Treg therapy in humans. This review focuses on developing therapy for transplantation using CD4(+)Foxp3(+) Tregs, with an emphasis on the studies that have informed clinical approaches that aim to maximize the benefits while overcoming the challenges and risks of Treg cell therapy.
Collapse
Affiliation(s)
- Qizhi Tang
- Division of Transplantation, Department of Surgery, University of California San Francisco, San Francisco, CA 94143-0780, USA.
| | | | | |
Collapse
|
14
|
Distinct strategies are required to suppress antigen-specific responses to genetically modified keratinocytes and fibroblasts. Mol Ther 2011; 20:196-203. [PMID: 21988876 DOI: 10.1038/mt.2011.205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Keratinocytes and fibroblasts are potential targets of gene/cell therapy for genodermatoses. Immune elimination of genetically modified cells, however, presents a major impediment to effective therapy. Using ex vivo approaches to gene transfer, we have previously shown that expression of an antigen by either cell type in skin induces immune rejection of transplanted cells, although the nature of immune responses induced by these two cell types are distinct. In this study, we explore the efficacy of local immunosuppressive strategies to divert destructive immune responses from genetically modified fibroblast and keratinocytes. Expression of CTLA4Ig and, to a lesser extent, PDL1, by antigenic fibroblasts protected them from immune rejection resulting in long-term graft survival (>18 weeks). Similar treatment was not effective for antigenic keratinocytes. Long-term protection of transgenic keratinocytes was achieved through transient blockade of CD40/CD154 interactions during the first 2 weeks of cell transplantation. Although neither of these strategies induced antigen-specific tolerance, they were sufficient to prevent rejection of genetically modified cells. These results indicate that different strategies are required to protect antigenic cell types even within the same tissue. Moreover, induction of antigen-specific tolerance is not a necessary requirement for long-term survival of genetically modified skin cells.
Collapse
|
15
|
Du W, Shen H, Galan A, Goldstein DR. An age-specific CD8+ T cell pathway that impairs the effectiveness of strategies to prolong allograft survival. THE JOURNAL OF IMMUNOLOGY 2011; 187:3631-40. [PMID: 21873523 DOI: 10.4049/jimmunol.1100441] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Age-related decline in immunity can impair cell-mediated responses during an infection, malignancy, and acute allograft rejection. Although much research has been allocated to understand the immune responses that impact the former two conditions, the cellular mechanisms by which aging impacts the immune acceptance of organ allografts are not completely clear. In this study, we examined how recipient age impacts the efficacy of therapies that modulate immune recognition of allografts using an immunogenic murine skin transplant model. We found that costimulatory blockade-based treatment failed to extend allograft survival in older recipients to the same extent as that observed in younger recipients. CD8(+) T cells were critical for the inability of aged recipients to achieve maximal allograft survival. Although aged mice displayed a larger number of effector memory T cells prior to transplantation, these cells did not exhibit enhanced alloreactivity compared with young memory T cells. In contrast, naive aged CD8(+) T cells exhibited enhanced IFN-γ production to allostimulation compared with young naive T cells. Our results provide evidence that aging enhances CD8(+) T cell alloreactivity. This could impair the ability of costimulatory blockade-based therapies to prolong allograft survival. Thus, targeting CD8(+) T cells in humans may be a way to improve outcomes in older patients requiring immune modulatory therapy.
Collapse
Affiliation(s)
- Wei Du
- Department of Internal Medicine and Immunobiology, Yale University School of Medicine, New Haven, CT 06525, USA
| | | | | | | |
Collapse
|
16
|
Wang Y, Camirand G, Lin Y, Froicu M, Deng S, Shlomchik WD, Lakkis FG, Rothstein DM. Regulatory T cells require mammalian target of rapamycin signaling to maintain both homeostasis and alloantigen-driven proliferation in lymphocyte-replete mice. THE JOURNAL OF IMMUNOLOGY 2011; 186:2809-18. [PMID: 21270412 DOI: 10.4049/jimmunol.0903805] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Rapamycin (Rapa), an immunosuppressive drug that acts through mammalian target of Rapa inhibition, broadly synergizes with tolerogenic agents in animal models of transplantation and autoimmunity. Rapa preferentially inhibits conventional CD4(+) Foxp3(-) T cells (Tconv) and promotes outgrowth of CD4(+)Foxp3(+) regulatory T cells (Treg) during in vitro expansion. Moreover, Rapa is widely perceived as augmenting both expansion and conversion of Treg in vivo. However, most quantitative studies were performed in lymphopenic hosts or in graft-versus-host disease models. We show in this study that in replete wild-type mice, Rapa significantly inhibits both homeostatic and alloantigen-induced proliferation of Treg, and promotes their apoptosis. Together, these lead to significant Treg depletion. Tconv undergo depletion to a similar degree, resulting in no change in the percent of Treg among CD4 cells. Moreover, in this setting, there was no evidence of conversion of Tconv into Treg. However, after withdrawal of Rapa, Treg recover Ag-induced proliferation more quickly than Tconv, leading to recovery to baseline numbers and an increase in the percent of Treg compared with Tconv. These findings suggest that the effects of Rapa on Treg survival, homeostasis, and induction, depend heavily on the cellular milieu and degree of activation. In vivo, the resistance of Treg to mammalian target of Rapa inhibition is relative and results from lymphopenic and graft-versus-host disease models cannot be directly extrapolated to settings more typical of solid organ transplantation or autoimmunity. Moreover, these results have important implications for the timing of Rapa therapy with tolerogenic agents designed to increase the number of Treg in vivo.
Collapse
Affiliation(s)
- Ying Wang
- Thomas E Starzl Transplantation Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Abstract
The thymus serves as the central organ of immunologic self-nonself discrimination. Thymocytes undergo both positive and negative selection, resulting in T cells with a broad range of reactivity to foreign antigens but with a lack of reactivity to self-antigens. The thymus is also the source of a subset of regulatory T cells that inhibit autoreactivity of T-cell clones that may escape negative selection. As a result of these functions, the thymus has been shown to be essential for the induction of tolerance in many rodent and large animal models. Proper donor antigen presentation in the thymus after bone marrow, dendritic cell, or solid organ transplantation has been shown to induce tolerance to allografts. The molecular mechanisms of positive and negative selection and regulatory T-cell development must be understood if a tolerance-inducing therapeutic intervention is to be designed effectively. In this brief and selective review, we present some of the known information on T-cell development and on the role of the thymus in experimental models of transplant tolerance. We also cite some clinical attempts to induce tolerance to allografts using pharmacologic or biologic interventions.
Collapse
|
18
|
|
19
|
Tian C, Yuan X, Jindra PT, Bagley J, Sayegh MH, Iacomini J. Induction of transplantation tolerance to fully mismatched cardiac allografts by T cell mediated delivery of alloantigen. Clin Immunol 2010; 136:174-87. [PMID: 20452826 DOI: 10.1016/j.clim.2010.04.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 04/14/2010] [Accepted: 04/14/2010] [Indexed: 01/11/2023]
Abstract
Induction of transplantation tolerance has the potential to allow for allograft acceptance without the need for life-long immunosuppression. Here we describe a novel approach that uses delivery of alloantigen by mature T cells to induce tolerance to fully allogeneic cardiac grafts. Adoptive transfer of mature alloantigen-expressing T cells into myeloablatively conditioned mice results in long-term acceptance of fully allogeneic heart transplants without evidence of chronic rejection. Since myeloablative conditioning is clinically undesirable we further demonstrated that adoptive transfer of mature alloantigen-expressing T cells alone into mice receiving non-myeloablative conditioning resulted in long-term acceptance of fully allogeneic heart allografts with minimal evidence of chronic rejection. Mechanistically, tolerance induction involved both deletion of donor-reactive host T cells and the development of regulatory T cells. Thus, delivery of alloantigen by mature T cells induces tolerance to fully allogeneic organ allografts in non-myeloablatively conditioned recipients, representing a novel approach for tolerance induction in transplantation.
Collapse
Affiliation(s)
- Chaorui Tian
- Brigham and Women's Hospital and Children's Hospital Boston, Harvard Medical School, Boston, MA, USA
| | | | | | | | | | | |
Collapse
|
20
|
Kim JI, Sonawane SB, Lee MK, Lee SH, Duff PE, Moore DJ, O’Connor MR, Lian MM, Deng S, Choi Y, Yeh H, Caton AJ, Markmann JF. Blockade of GITR-GITRL interaction maintains Treg function to prolong allograft survival. Eur J Immunol 2010; 40:1369-74. [PMID: 20148423 PMCID: PMC2935584 DOI: 10.1002/eji.200940046] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Involvement of Treg in transplant tolerance has been demonstrated in multiple models. During the active process of graft rejection, these regulatory cells are themselves regulated and inactivated, a process termed counter-regulation. We hypothesize that ligation of the costimulatory molecule glucocorticoid-induced TNF receptor-related protein (GITR) on Treg inhibits their ability to promote graft survival, and by blocking GITR ligation graft survival can be prolonged. To this aim, we have designed a soluble GITR fusion protein (GITR-Fc), which binds GITR ligand and inhibits activation of GITR. Here, we show that GITR-Fc prolonged mouse skin graft survival, and this prolongation is dependent on Treg. In a full MHC-mismatched skin graft setting, GITR-Fc significantly improved graft survival when used in combination with MR1, anti-CD40L, while GITR-Fc alone did not demonstrate graft prolongation. These results demonstrate that disruption of binding of GITR with GITR ligand may be an important strategy in prolonging allograft survival.
Collapse
MESH Headings
- Adoptive Transfer
- Animals
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal/therapeutic use
- Antigen-Presenting Cells/drug effects
- Antigen-Presenting Cells/immunology
- Binding, Competitive
- CD40 Ligand
- Glucocorticoid-Induced TNFR-Related Protein
- Graft Survival/drug effects
- Histocompatibility Antigens Class I
- Humans
- Immune Tolerance/drug effects
- Immunosuppressive Agents/administration & dosage
- Immunosuppressive Agents/pharmacology
- Immunosuppressive Agents/therapeutic use
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Transgenic
- Minor Histocompatibility Antigens
- Receptors, Nerve Growth Factor/genetics
- Receptors, Nerve Growth Factor/immunology
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor/immunology
- Recombinant Fusion Proteins/administration & dosage
- Recombinant Fusion Proteins/pharmacology
- Recombinant Fusion Proteins/therapeutic use
- Skin Transplantation/immunology
- T-Lymphocytes, Regulatory/immunology
- Transplantation, Homologous/immunology
- Tumor Necrosis Factor Inhibitors
- Tumor Necrosis Factors/immunology
Collapse
Affiliation(s)
- James I. Kim
- Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Samsher B. Sonawane
- Harrison Department of Surgical Research, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Major K. Lee
- Harrison Department of Surgical Research, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Seoung-Hoon Lee
- Abramson Family Cancer Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Patrick E. Duff
- Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Daniel J. Moore
- Department of Pediatrics, Vanderbilt Children’s Hospital, Nashville, TN, USA
| | | | - Moh-Moh Lian
- Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Shaoping Deng
- Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Yongwon Choi
- Abramson Family Cancer Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Heidi Yeh
- Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | | | - James F. Markmann
- Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| |
Collapse
|
21
|
|
22
|
Gorczynski RM, Chen Z, He W, Khatri I, Sun Y, Yu K, Boudakov I. Expression of a CD200 transgene is necessary for induction but not maintenance of tolerance to cardiac and skin allografts. THE JOURNAL OF IMMUNOLOGY 2009; 183:1560-8. [PMID: 19592654 DOI: 10.4049/jimmunol.0900200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CD200, a type 2 transmembrane molecule of the Ig supergene family, can induce immunosuppression in a number of biological systems, as well as promote increased graft acceptance, following binding to its receptors (CD200Rs). Skin and cardiac allograft acceptance are readily induced in transgenic mice overexpressing CD200 under control of a doxycycline-inducible promoter, both of which are associated with increased intragraft expression of mRNAs for a number of genes associated with altered T cell subset differentiation, including GATA-3, type 2 cytokines (IL-4, IL-13), GITR, and Foxp3. Interestingly, some 12-15 days after grafting, induction of transgenic CD200 expression can be stopped (by doxycycline withdrawal), without obvious significant effect on graft survival. However, neutralization of all CD200 expression (including endogenous CD200 expression) by anti-CD200 mAb caused graft loss, as did introduction of an acute inflammatory stimulus (LPS, 10 microg/mouse, delivered by i.p. injection). We conclude that even with apparently stably accepted tissue allografts, disruption of the immunoregulatory balance by an intense inflammatory stimulus can cause graft loss.
Collapse
|
23
|
Li XC, Rothstein DM, Sayegh MH. Costimulatory pathways in transplantation: challenges and new developments. Immunol Rev 2009; 229:271-93. [DOI: 10.1111/j.1600-065x.2009.00781.x] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
24
|
Shen H, Goldstein DR. IL-6 and TNF-alpha synergistically inhibit allograft acceptance. J Am Soc Nephrol 2009; 20:1032-40. [PMID: 19357252 DOI: 10.1681/asn.2008070778] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Previous studies suggested that activation of the innate immune system impairs the induction of transplantation tolerance, but the responsible inflammatory mediators have not been identified. In this study, we examined whether IL-6 and TNF-alpha promote resistance to transplantation tolerance. Using a highly immunogenic murine skin allograft model, we found that the absence of both IL-6 and TNF-alpha in the graft recipient synergized with co-stimulatory blockade to induce tolerance. Furthermore, IL-6 and TNF-alpha acted together to promote T cell alloimmune responses both in vitro and in vivo and to impair the ability of regulatory T cells to suppress effector T cell alloimmunity. In addition, deficiency of recipient IRAK-M, a negative regulator of certain innate immune pathways, augmented cellular IL-6 and TNF-alpha responses and impaired the ability of co-stimulatory blockade to extend allograft survival. In summary, IL-6 and TNF-alpha synergistically impair the efficacy of therapies that promote allograft acceptance.
Collapse
Affiliation(s)
- Hua Shen
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | | |
Collapse
|
25
|
Greenlaw RE, Gardner NJ, Farrar CA, Shariff H, Sacks SH, Yagita H, Simpson E, Jurcevic S. An antibody combination that targets activated T cells extends graft survival in sensitized recipients. Am J Transplant 2008; 8:2272-82. [PMID: 18785958 DOI: 10.1111/j.1600-6143.2008.02393.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Memory T cells are the very essence of adaptive immunity with their rapid and efficient response to antigen rechallenge and long-term persistence. However, it is becoming increasingly evident that when primed with self or transplanted tissue, these cells play a key role in causing and perpetuating tissue damage. Furthermore, current treatments, which efficiently control the naive response, have limited effects on primed T cells. We have used a treatment based on a combination of antibodies specific for molecules expressed by activated T lymphocytes to selectively remove these cells. This approach, which we termed multi-hit therapy, leads to cumulative binding of antibodies to the target T cells and a striking prolongation of skin graft survival in presensitized recipients in a stringent skin transplant model. The findings are consistent with the depletion of graft-specific CD4+ and CD8+ T cells, although other modes of action, such as T-cell regulation and altered migration could play a role. In conclusion, our therapeutic strategy controls primed T cells which are a major driving force in the pathology of many autoimmune diseases and in transplant rejection.
Collapse
Affiliation(s)
- R E Greenlaw
- Department of Nephrology and Transplantation, King's College London, Guy's Hospital, London, UK
| | | | | | | | | | | | | | | |
Collapse
|
26
|
del Rio ML, Buhler L, Gibbons C, Tian J, Rodriguez-Barbosa JI. PD-1/PD-L1, PD-1/PD-L2, and other co-inhibitory signaling pathways in transplantation. Transpl Int 2008; 21:1015-28. [PMID: 18662368 DOI: 10.1111/j.1432-2277.2008.00726.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Transplantation of cells, tissues and vascularized solid organs is a successful therapeutic intervention for many end-stage chronic diseases. The combination of co-stimulatory blockade with the delivery of negative signals to T cells through co-inhibitory receptors would provide a robust approach to modulating T-cell receptor signaling and improving alloantigen-specific control of transplant rejection. This approach based on fundamental knowledge of APC/T-cell interactions may complement conventional therapies in the near future to reinforce long-term allograft survival, and permit minimal immunosuppression. The focus of this review was primarily on two major co-inhibitory signaling pathways, namely PD-1/PD-L1/PD-L2 and BTLA/CD160/HVEM/LIGHT that have been thoroughly characterized in murine models of transplantation using genetically modified mice, specific monoclonal antibodies and fusion proteins.
Collapse
Affiliation(s)
- Maria-Luisa del Rio
- Laboratory of Immunobiology, School of Biotechnology and Institute of Biomedicine, University of Leon, Leon, Spain
| | | | | | | | | |
Collapse
|
27
|
Snanoudj R, Frangié C, Deroure B, François H, Créput C, Beaudreuil S, Dürrbach A, Charpentier B. The blockade of T-cell co-stimulation as a therapeutic stratagem for immunosuppression: Focus on belatacept. Biologics 2007; 1:203-13. [PMID: 19707331 PMCID: PMC2721321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The development of immunosuppressive drugs has in recent years been focused on prevention of acute rejection. This has led to an increase in one-year allograft survival. However, these drugs have non-immune effects which contribute to the high incidence of late graft loss, as a consequence of chronic allograft nephropathy, and the death of patients. As an immune-specific alternative to conventional immunosuppressants, new biotechnology tools have been developed; they target the costimulation signal of T-cell activation, particularly by the "classical" B7/CD28 and CD40/CD40L pathways. Here, we review the limitations of current immunosuppressive protocols, the benefits of classical B7/CD28 costimulation blockade, and the first large-scale clinical application of this strategy to human transplantation with belatacept. We will also consider novel costimulatory molecules of the B7/CD28 and TNF/TNF-R families, which appear to be important for the functions of memory and effector T-cells.
Collapse
Affiliation(s)
- Renaud Snanoudj
- Service de Néphrologie et Transplantation Rénale, Hôpital du Kremlin Bicêtre, Assistance Publique Hôpitaux de Paris; Le Kremlin-Bicêtre; France
- INSERM UMR542, Université Paris-Sud, Villejuif, France
| | - Carlos Frangié
- Service de Néphrologie et Transplantation Rénale, Hôpital du Kremlin Bicêtre, Assistance Publique Hôpitaux de Paris; Le Kremlin-Bicêtre; France
- INSERM UMR542, Université Paris-Sud, Villejuif, France
| | - Benjamin Deroure
- Service de Néphrologie et Transplantation Rénale, Hôpital du Kremlin Bicêtre, Assistance Publique Hôpitaux de Paris; Le Kremlin-Bicêtre; France
| | - Hélène François
- Service de Néphrologie et Transplantation Rénale, Hôpital du Kremlin Bicêtre, Assistance Publique Hôpitaux de Paris; Le Kremlin-Bicêtre; France
- INSERM UMR542, Université Paris-Sud, Villejuif, France
| | - Caroline Créput
- Service de Néphrologie et Transplantation Rénale, Hôpital du Kremlin Bicêtre, Assistance Publique Hôpitaux de Paris; Le Kremlin-Bicêtre; France
- INSERM UMR542, Université Paris-Sud, Villejuif, France
| | - Séverine Beaudreuil
- Service de Néphrologie et Transplantation Rénale, Hôpital du Kremlin Bicêtre, Assistance Publique Hôpitaux de Paris; Le Kremlin-Bicêtre; France
| | - Antoine Dürrbach
- Service de Néphrologie et Transplantation Rénale, Hôpital du Kremlin Bicêtre, Assistance Publique Hôpitaux de Paris; Le Kremlin-Bicêtre; France
- INSERM UMR542, Université Paris-Sud, Villejuif, France
| | - Bernard Charpentier
- Service de Néphrologie et Transplantation Rénale, Hôpital du Kremlin Bicêtre, Assistance Publique Hôpitaux de Paris; Le Kremlin-Bicêtre; France
- INSERM UMR542, Université Paris-Sud, Villejuif, France
| |
Collapse
|
28
|
Snanoudj R, de Préneuf H, Créput C, Arzouk N, Deroure B, Beaudreuil S, Durrbach A, Charpentier B. Costimulation blockade and its possible future use in clinical transplantation. Transpl Int 2006; 19:693-704. [PMID: 16918529 DOI: 10.1111/j.1432-2277.2006.00332.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The nonimmune effects of currently used immunosuppressive drugs result in a high incidence of late graft loss due to nephrotoxicity and death of patients. As an immune-specific alternative to conventional immunosuppressants, new biotechnology tools can be used to block the costimulation signals of T-cell activation. Many experimental studies--particularly preclinical studies in nonhuman primates--have focused on blocking the 'classical' B7/CD28 and CD40/CD40L pathways, which are critical in primary T-cell activation. Here, we review the limitations, the recent advances and the first large-scale clinical application of the CTLA4-Ig fusion protein to block the B7/CD28 costimulation pathway. We also focus on new B7/CD28 and tumor necrosis factor (TNF)/TNF-R family costimulatory molecules that can deliver positive or negative costimulation signals regulating the alloimmune response. Strategies that use single agents to block costimulation have often proved to be insufficient. Given the diversity of the different costimulation molecules, future strategies for human transplantation may involve the simultaneous blockade of several selected pathways or the simultaneous use of conventional immunosuppressants.
Collapse
Affiliation(s)
- Renaud Snanoudj
- Service de Néphrologie et Transplantation Rénale, Hôpital du Kremlin Bicêtre, Le Kremlin-Bicêtre, INSERM U542, Villejuif, France.
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Walker WE, Nasr IW, Camirand G, Tesar BM, Booth CJ, Goldstein DR. Absence of Innate MyD88 Signaling Promotes Inducible Allograft Acceptance. THE JOURNAL OF IMMUNOLOGY 2006; 177:5307-16. [PMID: 17015716 DOI: 10.4049/jimmunol.177.8.5307] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Prior experimental strategies to induce transplantation tolerance have focused largely on modifying adaptive immunity. However, less is known concerning the role of innate immune signaling in the induction of transplantation tolerance. Using a highly immunogenic murine skin transplant model that resists transplantation tolerance induction when innate immunity is preserved, we show that absence of MyD88, a key innate Toll like receptor signal adaptor, abrogates this resistance and facilitates inducible allograft acceptance. In our model, absence of MyD88 impairs inflammatory dendritic cell responses that reduce T cell activation. This effect increases T cell susceptibility to suppression mediated by CD4+ CD25+ regulatory T cells. Therefore, this study provides evidence that absence of MyD88 promotes inducible allograft acceptance and implies that inhibiting innate immunity may be a potential, clinically relevant strategy to facilitate transplantation tolerance.
Collapse
Affiliation(s)
- Wendy E Walker
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | | | | | | | | | | |
Collapse
|
30
|
Pierson RN. Primate T-cell responses to porcine antigens: implications for clinical xenotransplantation. Xenotransplantation 2006; 13:14-8. [PMID: 16497208 DOI: 10.1111/j.1399-3089.2005.00268.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Richard N Pierson
- Department of Surgery, University of Maryland Medical System Staff Surgeon, Baltimore VAMC, Baltimore, MD, USA.
| |
Collapse
|