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Ghorpade DS, Holla S, Sinha AY, Alagesan SK, Balaji KN. Nitric oxide and KLF4 protein epigenetically modify class II transactivator to repress major histocompatibility complex II expression during Mycobacterium bovis bacillus Calmette-Guerin infection. J Biol Chem 2013; 288:20592-606. [PMID: 23733190 DOI: 10.1074/jbc.m113.472183] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Pathogenic mycobacteria employ several immune evasion strategies such as inhibition of class II transactivator (CIITA) and MHC-II expression, to survive and persist in host macrophages. However, precise roles for specific signaling components executing down-regulation of CIITA/MHC-II have not been adequately addressed. Here, we demonstrate that Mycobacterium bovis bacillus Calmette-Guérin (BCG)-mediated TLR2 signaling-induced iNOS/NO expression is obligatory for the suppression of IFN-γ-induced CIITA/MHC-II functions. Significantly, NOTCH/PKC/MAPK-triggered signaling cross-talk was found critical for iNOS/NO production. NO responsive recruitment of a bifunctional transcription factor, KLF4, to the promoter of CIITA during M. bovis BCG infection of macrophages was essential to orchestrate the epigenetic modifications mediated by histone methyltransferase EZH2 or miR-150 and thus calibrate CIITA/MHC-II expression. NO-dependent KLF4 regulated the processing and presentation of ovalbumin by infected macrophages to reactive T cells. Altogether, our study delineates a novel role for iNOS/NO/KLF4 in dictating the mycobacterial capacity to inhibit CIITA/MHC-II-mediated antigen presentation by infected macrophages and thereby elude immune surveillance.
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Affiliation(s)
- Devram Sampat Ghorpade
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
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Sagoo P, Lombardi G, Lechler RI. Relevance of regulatory T cell promotion of donor-specific tolerance in solid organ transplantation. Front Immunol 2012; 3:184. [PMID: 22811678 PMCID: PMC3395995 DOI: 10.3389/fimmu.2012.00184] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 06/14/2012] [Indexed: 01/29/2023] Open
Abstract
Current clinical strategies to control the alloimmune response after transplantation do not fully prevent induction of the immunological processes which lead to acute and chronic immune-mediated graft rejection, and as such the survival of a solid organ allograft is limited. Experimental research on naturally occurring CD4+CD25highFoxP3+ Regulatory T cells (Tregs) has indicated their potential to establish stable long-term graft acceptance, with the promise of providing a more effective therapy for transplant recipients. Current approaches for clinical use are based on the infusion of freshly isolated or ex vivo polyclonally expanded Tregs into graft recipients with an aim to redress the in vivo balance of T effector cells to Tregs. However mounting evidence suggests that regulation of donor-specific immunity may be central to achieving immunological tolerance. Therefore, the next stages in optimizing translation of Tregs to organ transplantation will be through the refinement and development of donor alloantigen-specific Treg therapy. The altering kinetics and intensity of alloantigen presentation pathways and alloimmune priming following transplantation may indeed influence the specificity of the Treg required and the timing or frequency at which it needs to be administered. Here we review and discuss the relevance of antigen-specific regulation of alloreactivity by Tregs in experimental and clinical studies of tolerance and explore the concept of delivering an optimal Treg for the induction and maintenance phases of achieving transplantation tolerance.
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Affiliation(s)
- Pervinder Sagoo
- Department Transplantation, Immunoregulation and Mucosal Biology, MRC Centre for Transplantation, King's College London London, UK
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Ladhoff J, Fleischer B, Hara Y, Volk HD, Seifert M. Immune privilege of endothelial cells differentiated from endothelial progenitor cells. Cardiovasc Res 2010; 88:121-9. [PMID: 20388638 DOI: 10.1093/cvr/cvq109] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
AIMS The application of autologous endothelial progenitor cells (EPC) is a promising approach in cardiovascular regeneration, but the availability of cells in appropriate numbers is the limiting factor. Allogeneic EPC would be an alternative, and we therefore analysed the immunogenicity of EPC-derived endothelial cells (EC) to evaluate their potential usefulness. METHODS AND RESULTS Circulating EPC from rat were differentiated into EC and characterized phenotypically and functionally. Major histocompatibility complex (MHC) expression in response to interferon-gamma was determined compared with rat aortic EC, and in vitro humoral and cellular allogeneic responses were analysed. To determine the in vivo effects, acellular aortic grafts were endothelialized in vitro with EPC-derived EC and transplanted in a complete allogeneic mismatch rat aortic interposition model. EPC-derived EC expressed endothelial-specific markers and low levels of MHC class I (MHC I), but no constitutive MHC class II (MHC II). When stimulated with interferon-gamma, they upregulated MHC I and moderately upregulated MHC II. They were protected against alloantibody/complement-mediated lysis and allospecific cytotoxic T lymphocyte activity. They were less potent in allogeneic stimulation of CD4 T cells than aortic EC. Seeding of EPC-derived EC into acellular grafts led to excellent endothelialization, and allogeneic aortic transplantation induced only mild inflammatory responses without signs of rejection. CONCLUSION EPC-derived EC are protected against allospecific cellular immune responses and humoral-mediated attacks in vitro. When transplanted in vivo as a component of vascular grafts, these cells are not rejected, which makes them useful in therapeutic applications, especially vascular reconstruction.
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Affiliation(s)
- Juliane Ladhoff
- Institute of Medical Immunology, Charité Universitätsmedizin Berlin, Berlin, Germany
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Low immunogenicity of endothelial derivatives from rat embryonic stem cell-like cells. Cell Res 2009; 19:507-18. [PMID: 19238174 DOI: 10.1038/cr.2009.21] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Embryonic stem cells (ESC) are suggested to be immune-privileged, but they carry the risk of uncontrolled expansion and malignancy. Upon differentiation they lose their tumor-forming capacity, but they become immunogenic by the expression of a normal set of MHC molecules. This immunogenicity might trigger rejection after application in regenerative therapies. In this study MHC expression of and immune responses to endothelial derivatives of rat embryonic stem cell-like cells (RESC) under inflammatory conditions were determined in comparison to primary rat aortic endothelial cells (ECs). Cellular as well as humoral allo-recognition was analyzed in vitro. In addition, immune reactions in vivo were assessed by allo-antibody production and determination of interferon-gamma (IFNgamma)-secreting allo-reactive T cells. RESC derivatives expressed low but significant levels of MHC class I, and no MHC class II. In response to IFNgamma MHC class I expression was enhanced, while class II transactivator induction failed completely in these cells; MHC class II expression remained consistently absent. Functionally, the RESC derivatives showed a reduced allo-stimulatory capacity, protection against humoral allo-recognition in vitro and a slightly diminished susceptibility to cytotoxic T cell lysis. Furthermore, in vivo experiments demonstrated that these cells do not trigger host immune reactions, characterized by no allo-antibody production and no induction of allo-reactive memory T cells. Our results show that endothelial derivatives of RESC have a distinctive reduced immunogenic potency even under inflammatory conditions.
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Toyokawa H, Nakao A, Bailey RJ, Nalesnik MA, Kaizu T, Lemoine JL, Ikeda A, Tomiyama K, Papworth GD, Huang L, Demetris AJ, Starzl TE, Murase N. Relative contribution of direct and indirect allorecognition in developing tolerance after liver transplantation. Liver Transpl 2008; 14:346-57. [PMID: 18306376 PMCID: PMC3022430 DOI: 10.1002/lt.21378] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The interaction of donor passenger leukocytes and host leukocytes in recipient secondary lymphoid tissues during the early posttransplantation period is crucial in directing host immune reactions toward allograft rejection or acceptance. Responsible T cell clones could be activated through the direct and indirect pathways of allorecognition. We examined the role of the indirect pathway in liver transplantation (LT) tolerance by depleting host antigen-presenting cells (APC) with phagocytic activity [e.g., cluster domain (CD)68+/CD163+ macrophages, CD11c+ dendritic cells (DC)] using liposome-encapsulating clodronate (LP-CL). After Lewis rat cell or liver graft transplantation, Brown Norway (BN) rat recipients pretreated with LP-CL showed a significantly reduced type 1 helper T cell cytokine up-regulation than control-LP-treated recipients. In the LT model, LP-CL treatment and host APC depletion abrogated hepatic tolerance; Lewis liver grafts in LP-CL-treated-BN recipients developed mild allograft rejection, failed to maintain donor major histocompatibility complex (MHC) class II+ leukocytes, and developed chronic rejection in challenged donor heart allografts, while control-LP-treated BN recipients maintained tolerance status and donor MHC class II+ hepatic leukocytes. Furthermore, in the BN to Lewis LT model, LP-CL recipient treatment abrogated spontaneous hepatic allograft acceptance, and graft survival rate was reduced to 43% from 100% in the control-LP group. In conclusion, the study suggests that host cells with phagocytic activity could play significant roles in developing LT tolerance.
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Affiliation(s)
- Hideyoshi Toyokawa
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Atsunori Nakao
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Robert J. Bailey
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Michael A. Nalesnik
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Takashi Kaizu
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Jerome L. Lemoine
- Center for Pharmacogenetics, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Atsushi Ikeda
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Koji Tomiyama
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Glenn D. Papworth
- Center for Biologic Imaging, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Leaf Huang
- Center for Pharmacogenetics, University of Pittsburgh Medical Center, Pittsburgh, PA
- Division of Molecular Pharmaceutics, School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Anthony J. Demetris
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Thomas E. Starzl
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Noriko Murase
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA
- Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
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Famulski KS, Broderick G, Einecke G, Hay K, Cruz J, Sis B, Mengel M, Halloran PF. Transcriptome analysis reveals heterogeneity in the injury response of kidney transplants. Am J Transplant 2007; 7:2483-95. [PMID: 17908279 DOI: 10.1111/j.1600-6143.2007.01980.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We studied the transcripts that are increased by stress and injury in mouse kidney transplants, focusing on transcripts increased in parenchymal cells-injury and repair-induced transcripts (IRITs). We compared four types of stressed kidneys: isografts, allografts, host kidneys of mice with isografts and nontransplant kidneys with ischemic acute tubular necrosis (ATN). After excluding transcripts associated with infiltrating cells and interferon-gamma-induced transcripts, we defined 790 IRITs in isografts. IRITs were remarkably heterogeneous in timing and mechanisms. Some were increased in host as well as donor kidneys, reflecting systemic influences (wounding, anesthetic). Most reflected local stress, resembling changes in ATN despite the lack of ATN histopathology. Mathematical decomposition of IRIT expression patterns confirmed heterogeneity, separating IRIT changes into component subsets, with an early peak (day 1) showing systemic effects and late peaks that resembled ATN, manifested Tgf-ss1 effects and recapitulated embryonic development. In allografts IRITs were initially similar to isografts but diverged due to allogeneic injury. The allospecific induction of IRITs was T-cell-dependent but perforin-granzyme-independent, compatible with delayed type hypersensitivity. The alloresponse strikingly and selectively increased the late IRITs but not the IRITs that peak early, indicating that rejection triggers parenchymal responses similar to those in ATN.
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Affiliation(s)
- K S Famulski
- Division of Nephrology & Transplantation Immunology, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
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Csencsits K, Wood SC, Lu G, Magee JC, Eichwald EJ, Chang CH, Bishop DK. Graft rejection mediated by CD4+ T cells via indirect recognition of alloantigen is associated with a dominant Th2 response. Eur J Immunol 2005; 35:843-51. [PMID: 15714582 DOI: 10.1002/eji.200425685] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
CD4(+) T cells that respond to indirectly presented alloantigen have been shown to mediate chronic rejection, however, the role of the indirect pathway in acute rejection has yet to be completely elucidated. To this end, BALB/c or C57BL/6 mice were depleted of CD8(+) T cells and transplanted with class II transactivator (CIITA)-deficient cardiac allografts, which cannot directly present class II alloantigens to CD4(+) T cells. In this manner, the rejection response by CD4(+) cells was forced to rely upon the indirect recognition pathway. When not depleted of CD8(+) cells, both BALB/c and C57BL/6 mice rejected CIITA-/- allografts and a polarized Th1 response was observed. In contrast, when BALB/c recipients of CIITA-/- allografts were depleted of CD8(+) T cells, the grafts were acutely rejected and a strong Th2 response characterized by eosinophil influx into the graft was observed. Interestingly, CD8-depleted C57BL/6 recipients of CIITA-/- allografts did not acutely reject their transplants and a Th2 response was not mounted. These findings indicate that CD4(+) T cells responding to indirectly presented alloantigens mediate graft rejection in a Th2-dominant manner, and provide further evidence for the role of Th2 responses in acute graft rejection.
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Affiliation(s)
- Keri Csencsits
- Department of Surgery, Section of General Surgery, University of Michigan School of Medicine, Ann Arbor, USA
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van der Woude FJ, Schnuelle P, Yard BA. Preconditioning Strategies to Limit Graft Immunogenicity and Cold Ischemic Organ Injury. J Investig Med 2004. [DOI: 10.1177/108155890405200532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
During the transplant process, the graft is exposed to numerous events, which may enhance its immunogenicity. In particular, factors related to brain death, such as hemodynamic instability and systemic release of cytokines, cold preservation on harvesting, and reperfusion injury, are known to accumulate in harm, conveying a proinflammatory state to the graft before transplant. Alloimmune reactivity is initiated when the host immune system detects non–self-antigens in the context of “danger signals.” Eliminating these danger signals by modifying the graft before transplant has the potential to attenuate the alloimmune response. The molecules, which mediate danger signals, have not yet been fully identified. Free oxygen radicals and interferon-γ are important candidates. One of the most important protective mechanisms against oxidative stress is the heme oxygenase 1 system. Up-regulation of heme oxygenase 1 in grafts has been shown to prevent ischemia-reperfusion damage and improve long-term graft survival in various transplant models. The benefit of blocking the action of interferon-γ in kidney transplants is less clear because the compound plays such a complex and pivotal role in the immune response, and experimental data with interferon-γ receptor knockout mice are conflicting. It has recently become clear that catecholamines are important graft-modifying agents. Dopamine is capable of stimulating the induction of protective enzymes like heme oxygenase-1 (HO-1) rendering the organ more resistant to the insult of ischemia/reperfusion and inflammation. Retrospective clinical data suggest that treatment of brain-dead organ donors with catecholamines is associated with less rejection and a better long-term graft survival of kidneys transplanted from these donors. Catecholamines can also modulate cytokine production and prevent cold-induced damage. Other substances, such as proteoglycans and phosphatidylethanolamine-bound hyaluronic acid, may interfere with the actions of interferon-γ. Further studies of these compounds in experimental animal models and in prospective randomized clinical trials will help establish their efficacy in donor pretreatment. It is important to underscore that donor pretreatment will have great advantages for the recipient because an improved long-term graft survival could thus be achieved cost-efficiently and without great effort or side effects.
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Affiliation(s)
- Fokko J. van der Woude
- Vth Medical University Clinic (Nephrology, Endocrinology, Rheumatology), Klinikum Mannheim, Ruprecht-Karls-Universitdt Heidelberg, Mannheim, Germany
| | - Peter Schnuelle
- Vth Medical University Clinic (Nephrology, Endocrinology, Rheumatology), Klinikum Mannheim, Ruprecht-Karls-Universitdt Heidelberg, Mannheim, Germany
| | - Benito A. Yard
- Vth Medical University Clinic (Nephrology, Endocrinology, Rheumatology), Klinikum Mannheim, Ruprecht-Karls-Universitdt Heidelberg, Mannheim, Germany
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Takeuchi O, Sims TN, Takei Y, Ramassar V, Famulski KS, Halloran PF. Differential Usage of Class II Transactivator Promoters PI and PIV during Inflammation and Injury in Kidney. J Am Soc Nephrol 2003; 14:2823-32. [PMID: 14569092 DOI: 10.1097/01.asn.0000094084.18567.cc] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
ABSTRACT. Expression of class II transactivator (CIITA), the transcriptional regulator that controls all class II expression, is controlled in cell linesin vitroby three promoters: the dendritic cell promoter PI, the B cell promoter PIII, and the interferon-γ (IFN-γ)–inducible promoter, PIV. The authors examined the promoter usagein vivoin mouse kidney in the basal state and in response to IFN-γ, endotoxin, allostimulation, and renal injury. Genetically modified mice were used to examine the dependency of each promoter on IFN-γ and on the transcription factor interferon regulatory factor 1 (IRF-1). Usage of distinct CIITA promoters was monitored by real-time reverse transcriptase polymerase chain reaction (RT-PCR) using the unique sequences in the 5′ end of the transcript from each promoter. Kidneys in both control mice and IFN-γ knockouts expressed chiefly PI- and PIV–related products. Administration of recombinant IFN-γ activated only promoter PIV. Endotoxin or allogeneic stimulation elevated the PIV-related mRNA, dependent on IFN-γ and on IRF-1. Ischemic renal injury, however, increased the PI- and PIV–driven mRNA expression in wild-type but also in IFN-γ–deficient mice. Thus thein vivocontrol of CIITA promoters in kidney is similar to that observedin vitro(i.e., basal-state usage of PI and IFN-γ–dependent usage of PIV during inflammation), but it also shows additional levels of control: IFN-γ–independent basal activity of PIV and IFN-γ–independent induction of PIV during tissue injury. E-mail: phil.halloran@ualberta.ca
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Affiliation(s)
- Oki Takeuchi
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
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van der Woude FJ, Schnuelle P, Yard BA. Graft immunogenicity and treatment of kidney donors. Transplant Rev (Orlando) 2003. [DOI: 10.1016/s0955-470x(03)00041-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Okuda T, Ishikawa T, Azhipa O, Ichikawa N, Demetris AJ, Starzl TE, Murase N. Early passenger leukocyte migration and acute immune reactions in the rat recipient spleen during liver engraftment: with particular emphasis on donor major histocompatibility complex class II+ cells. Transplantation 2002; 74:103-11. [PMID: 12134107 PMCID: PMC3154775 DOI: 10.1097/00007890-200207150-00018] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
After a short course of tacrolimus, Lewis rat liver allografts induce donor-specific nonreactivity in Brown Norway recipients that is immunosuppression-independent after 28 days. To clarify the role of donor major histocompatibility complex (MHC) class II+ cells, we investigated the migration to the recipient splenic T- and B-cell compartments of different subsets of Lewis MHC class II+ passenger leukocytes. The rise and decline of immune activation were monitored in the hepatic allograft and in the host spleen by analyses of BrdU+ (proliferating) leukocytes, TUNEL+ (apoptotic) cells, apoptosis-associated molecules, TH1/TH2 cytokine profiles, and histoimmunocytochemical examination of graft and splenic tissues. Serial flow cytometry studies during the 28-day period of drug-assisted "hepatic tolerogenesis" showed that migratory MHC class II+ cells accounted for less than half of the donor cells in the host spleen. The class II+ cells consisted mostly of B cells that homed to splenic B-cell follicles with only a sparse representation of dendritic cells that were exclusively found in the splenic periarteriolar lymphoid sheath. In parallel studies, transplantation of the less tolerogenic heart produced a diminutive version of the same events, but with far fewer donor cells in the host spleen, evidence of sustained immune activation, and the development of chronic rejection by 100 days. The data are consistent with the paradigm that migration of donor leukocytes is the prime determinant of variable tolerance induction induced by transplantation of the liver and other organs, but without regard for donor MHC class II+ expression.
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Affiliation(s)
- Toyokazu Okuda
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh Medical Center, Pennsylvania 15213, USA
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