The Experts below are selected from a list of 402 Experts worldwide ranked by ideXlab platform
David H Sachs - One of the best experts on this subject based on the ideXlab platform.
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effects of lung cotransplantation on cardiac allograft tolerance across a full major histocompatibility complex barrier in miniature swine
American Journal of Transplantation, 2016Co-Authors: Maria Lucia Madariaga, Philip J Spencer, Sebastian Michel, G M La Muraglia, M J Oneil, E C Mannon, C Leblang, Ivy A Rosales, Robert B Colvin, David H SachsAbstract:A 12-day course of high-dose tacrolimus induces tolerance of major histocompatibility complex-mismatched lung allografts in miniature swine but does not induce tolerance of heart allografts unless a kidney is cotransplanted. To determine whether lungs share with kidneys the ability to induce cardiac allograft tolerance, we investigated heart-lung cotransplantation using the same induction protocol. Hearts (n = 3), heart-kidneys (n = 3), lungs (n = 6), and hearts-lungs (n = 3) were transplanted into fully major histocompatibility complex-mismatched recipients treated with high-dose tacrolimus for 12 days. Serial biopsy samples were used to evaluate rejection, and in vitro assays were used to detect donor responsiveness. All heart-kidney recipients and five of six lung recipients demonstrated long-term graft survival for longer than 272 days, while all heart recipients rejected their allografts within 35 days. Tolerant recipients remained free of alloantibody and showed persistent donor-specific unresponsiveness by Cell-Mediated Lympholysis/mixed-lymphocyte reaction. In contrast, heart-lung recipients demonstrated rejection of both allografts (days 47, 55, and 202) and antidonor responsiveness in vitro. In contrast to kidneys, lung cotransplantation leads to rejection of both heart and lung allografts, indicating that lungs do not have the same tolerogenic capacity as kidneys. We conclude that Cells or Cell products present in kidney, but not heart or lung allografts, have a unique capacity to confer unresponsiveness on cotransplanted organs, most likely by amplifying host regulatory mechanisms.
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Brief Definitive Report Cell-Mediated Lympholysis OF TRINITROPHENYL-MODIFIED AUTOLOGOUS LYMPHOCYTES Confirmation of Genetic Control of Response to Trinitrophenyl-Modified H-2 Antigens by the Use of Anti-H-2 and Anti-Ia Antibodies
2013Co-Authors: Anne-marie Schmitr-verhulst, David H Sachs, M. ShearerAbstract:The in vitro induction of T-Cell-Mediated Lympholysis (CML) to trinitrophenyl (TNP)modified autologous spleen Cells has been demonstrated in the mouse (1). Lysis of modified splenic target Cells was obtained when there was K or D serological region homology between the target Cells and the Cells used in the sensitizing phase (2, 3). Experiments using F ~ responding lymphocytes sensitized and assayed with TNP-modified parental Cells indicated that homology between effector and target Cells was not sufficient to obtain lysis, but that the homology required was either between modified stimulating and modified target Cells, or among responding, modified stimulating and modified target Cells (2). These findings are compatible with the hypothesis that TNP is modifying Cell surface components controlled by the K and D serological regions of the major histocompatibility complex, and that the responding lymphocytes are reacting against these new antigenic specificities. Earlier studies have shown that sensitization of B10.A responding lymphocytes with TNP-modified autologous spleen Cells generated effector Cells which lysed TNP-modified K-end-matched target Cells, but not TNP-modified D-end-matched targets (2, 4). Thi
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linked suppression across an mhc mismatched barrier in a miniature swine kidney transplantation model
Journal of Immunology, 2008Co-Authors: Adam Griesemer, David H Sachs, John C Lamattina, Masayoshi Okumi, Justin Etter, Akira Shimizu, Kazuhiko YamadaAbstract:We have demonstrated previously that a 12-day course of FK506 permits the induction of tolerance to fully MHC-mismatched renal transplants in miniature swine. In the present study, we examined the mechanism of this tolerance by assessing the possibility that the survival of one-haplotype mismatched third-party kidneys might be prolonged via linked suppression. Ten SLA(d/d) miniature swine received fully MHC-mismatched renal allografts from SLA(c/c) donors with 12 days of FK506. Six animals received second SLA(c/c) kidneys without immunosuppression to confirm tolerance. Regulatory mechanisms were assessed by mixed lymphocyte reaction (MLR) and Cell-Mediated Lympholysis coculture assays and ELISA for regulatory cytokines. Linked suppression was investigated by transplanting SLA(a/c) or SLA(a/d) allografts into long-term tolerant recipients without immunosuppression. All recipients showed donor-specific unresponsiveness in standard Cell-Mediated Lympholysis and MLR assays. Tolerant Cells prestimulated with donor Ag and then cocultured with naive recipient MHC-matched Cells inhibited antidonor responses, confirming the presence of regulatory Cells. ELISA and MLR assays showed that TGF-beta2 was involved in mediating the suppression in vitro. SLA(a/d) renal allografts transplanted into tolerant recipients were rejected by postoperative day 8 (median, 7 days; range, 6-8). In contrast, SLA(a/c) allografts showed markedly prolonged survival (median, 52 days; range, 28-78; p = 0.0246), suggesting linked suppression. Animals not challenged with a second donor-matched graft did not manifest linked suppression consistent with in vitro data showing that re-exposure to tolerated Ags is important for generation of regulatory Cells. To our knowledge, these data represent the first evidence of linked suppression across fully MHC-mismatched barriers in a large animal model.
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role of the thymus and kidney graft in the maintenance of tolerance to heart grafts in miniature swine
Transplantation, 2005Co-Authors: J D Mezrich, David H Sachs, Parsia A Vagefi, Joren C Madsen, Louis C Benjamin, Jessica Sachs, Stuart L Houser, Kazuhiko YamadaAbstract:Background. The authors have examined the mechanism whereby co-transplantation of a kidney and heart from the same donor induces and maintains tolerance to both organs in miniature swine. Methods. Transplants were performed across a major histocompatibility complex class I mismatch, and recipients received cyclosporine for 12 days. Group 1 animals received heart transplants alone (n=5), and all other groups received both heart and kidney allografts. Group 2 animals received no further intervention (n=2). Group 3 animals underwent transplant nephrectomy 8 days after heart and kidney co-transplantation (n=2). Group 4 animals underwent transplant nephrectomy 100 days after co-transplantation (n=2). Skin grafts were placed on group 4 animals, on one group 3 animal, and on two animals from group 2. Group 5 animals underwent thymectomy 100 days after co-transplantation (n=4). Results. Group 1 animals developed cardiac allograft vasculopathy (CAV) and rejection. Group 2 animals never developed CAV and demonstrated in vitro donor-specific unresponsiveness. Group 3 animals suffered CAV and rejection. Group 4 animals developed CAV without concomitant donor-specific Cell-Mediated Lympholysis reactivity, interstitial rejection, or cessation of graft function. Skin grafts on group 3 and group 4 animals led to fulminant rejection of heart and skin grafts, in contrast to grafts on group 2 animals that had no in vivo effect. Group 5 animals developed CAV but no significant increase in interstitial infiltrates. Conclusions. Both the kidney and thymus were necessary for maintenance of tolerance to heart allografts.
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1 3 galactosyltransferase gene knockout miniature swine produce natural cytotoxic anti gal antibodies
Transplantation, 2004Co-Authors: F J M F Dor, Kazuhiko Yamada, Akira Shimizu, Yau Lin Tseng, Jane Cheng, K Moran, T M Sanderson, Courtney J Lancos, M Awwad, David H SachsAbstract:Background. The expression of galactoseal,3galactose (Gal) in pigs has proved a barrier to xenotransplantation Miniature swine lacking Gal (Gal -/- pigs) have been produced by nuclear transfer/embryo transfer. Methods. The tissues of five Gal -/- pigs of SLA dd haplotype (SLA dd ) were tested for the presence of Gal epitopes by staining with the Griffonia simplicifolia IB4 lectin. Their sera were tested by flow cytometry for binding of IgM and IgC to peripheral blood mononuclear Cells (PBMC) from wild-type (Gal +/+ ) SLA-matched pigs; serum cytotoxicity was also assessed. The Cellular responses of PBMC from Gal -/- swine toward Gal +/+ SLA-matched PBMC were tested by mixed leukocyte reaction and Cell-Mediated Lympholysis assays. Results. None of the tissues tested showed Gal expression. Sera from all five Gal -/- pigs manifested IgM binding tc Gal +/+ pig PBMC, and sera from three showed IgG binding. In all five cases, cytotoxicity to Gal +/+ Cells could b< demonstrated, which was lost after treatment of the sera with dithiothreitol, indicating IgM antibody-Mediated cytotoxicity. PBMC from Gal -/- swine had no proliferative or cytolytic T-Cell response toward Gal +/+ SLA-matchec PBMC. Conclusions. Gal -/- pigs do not express Gal epitopes and develop anti-Gal antibodies that are cytotoxic to Gal +/+ pig Cells. The absence of an in vitro Cellular immune response between Gal -/- and Gal +/+ pigs is related to their identica SLA haplotype and indicates the absence of immunogenicity of Gal in T-Cell responses. The model of Gal +/+ orgar transplantation into a Gal -/- SLA-matched recipient would be a valuable large animal model in the study of accommodation or B-Cell tolerance.
Kazuhiko Yamada - One of the best experts on this subject based on the ideXlab platform.
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tolerance and long lasting peripheral chimerism after allogeneic intestinal transplantation in mgh miniature swine
Transplantation, 2010Co-Authors: Yoshinori Ishikawa, Atsushi Hirakata, Adam Griesemer, Justin Etter, S Moran, Joshua Weiner, Akira Shimizu, Kazuhiko YamadaAbstract:Background and Objective. Clinical intestinal transplantation (Int-Tx) is limited by high rates of rejection, infection, and graft versus host disease. To improve clinical outcomes and eliminate the comorbidities associated with chronic immunosuppression, the induction of donor-specific tolerance to intestinal grafts is desirable, especially in the pediatric population. This study determined the ability of intestinal grafts to facilitate tolerance induction in major histo-compatibility complex (MHC)-inbred miniature swine. Methods. Seven MGH-miniature swine received heterotopic intestinal grafts, two across MHC-matched, minor-antigen disparities, three across a class I MHC disparity with 12 days of cyclosporine A, and two across a class I MHC disparity without an immunosuppressant. Chimerism was assessed by FACS analysis and immunohistochemistry. Cell-Mediated Lympholysis assays were used to assess antidonor responses. Results. Two animals receiving intestinal grafts without an immunosuppressant developed antidonor IgG in 14 days and rejected these completely. All other grafts were accepted with 12 days of cyclosporine A across both MHC-matched and MHC class I barriers. Cell-Mediated Lympholysis assays showed donor-specific unresponsiveness by day 30 across MHC class I barriers. Greater than 15% peripheral donor Cell chimerism persisted for more than 60 days after MHC-matched Int-Tx. Although less than 1.5% peripheral donor Cell chimerism was seen during the maintenance period after class I-mismatched Int-Tx, 5% to 10% myeloid chimerism was found in the peripheral blood 14 to 90 days after Int-Tx. FACS analysis demonstrated that 1% to 2% of lymphocytes in the graft mesenteric lymph nodes were CD4 + /CD25 high+ /Foxp3 + Cells. Conclusion. To our knowledge, this is the first demonstration of tolerance induction and persistence of chimerism in a large animal intestinal transplant model.
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porcine cfse mixed lymphocyte reaction and pkh 26 Cell Mediated Lympholysis assays
Transplant Immunology, 2008Co-Authors: Masayoshi Okumi, Kazuhiko Yamada, H Sahara, Atsushi Hirakata, Takashi Onoe, Adam GriesemerAbstract:Abstract Mixed lymphocyte reaction (MLR) and Cell-Mediated Lympholysis (CML) are widely used to assess T Cell responses. A major limitation of the traditional MLR and CML assays is that they require radioisotope labeling with 3 H for MLR and 51 Cr for CML, thereby limiting their use to laboratories with the capabilities to deal safely with these materials. Recently, flow cytometry with CFSE labeling has been used to detect Cell division in rodent and human assays, and flow cytometry with PKH-26 labeling has been used to study cytotoxicity in murine models. Partially inbred miniature swine provide a unique large animal preclinical model for experimental transplantation, helping to bridge the gap between rodent and clinical studies. In this study, we modified the reported CFSE and PKH-26 labeling procedures for use with porcine Cells, and established that these radioactive-free MLR and CML assays are comparable to traditional radioactive CML and MLR assays for assessing immunologic responses in miniature swine. To our knowledge, this is the first report that has directly compared the traditional CML/MLR with radiation-free CML/MLR in MHC-defined swine models. Objective The aim of this study is to establish non-radiolabeled CSFE and PKH-26 labeling procedures for flow cytometry based CML/MLR assays that are comparable to radioactive CML/MLR assays in preclinical large animals.
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linked suppression across an mhc mismatched barrier in a miniature swine kidney transplantation model
Journal of Immunology, 2008Co-Authors: Adam Griesemer, David H Sachs, John C Lamattina, Masayoshi Okumi, Justin Etter, Akira Shimizu, Kazuhiko YamadaAbstract:We have demonstrated previously that a 12-day course of FK506 permits the induction of tolerance to fully MHC-mismatched renal transplants in miniature swine. In the present study, we examined the mechanism of this tolerance by assessing the possibility that the survival of one-haplotype mismatched third-party kidneys might be prolonged via linked suppression. Ten SLA(d/d) miniature swine received fully MHC-mismatched renal allografts from SLA(c/c) donors with 12 days of FK506. Six animals received second SLA(c/c) kidneys without immunosuppression to confirm tolerance. Regulatory mechanisms were assessed by mixed lymphocyte reaction (MLR) and Cell-Mediated Lympholysis coculture assays and ELISA for regulatory cytokines. Linked suppression was investigated by transplanting SLA(a/c) or SLA(a/d) allografts into long-term tolerant recipients without immunosuppression. All recipients showed donor-specific unresponsiveness in standard Cell-Mediated Lympholysis and MLR assays. Tolerant Cells prestimulated with donor Ag and then cocultured with naive recipient MHC-matched Cells inhibited antidonor responses, confirming the presence of regulatory Cells. ELISA and MLR assays showed that TGF-beta2 was involved in mediating the suppression in vitro. SLA(a/d) renal allografts transplanted into tolerant recipients were rejected by postoperative day 8 (median, 7 days; range, 6-8). In contrast, SLA(a/c) allografts showed markedly prolonged survival (median, 52 days; range, 28-78; p = 0.0246), suggesting linked suppression. Animals not challenged with a second donor-matched graft did not manifest linked suppression consistent with in vitro data showing that re-exposure to tolerated Ags is important for generation of regulatory Cells. To our knowledge, these data represent the first evidence of linked suppression across fully MHC-mismatched barriers in a large animal model.
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role of the thymus and kidney graft in the maintenance of tolerance to heart grafts in miniature swine
Transplantation, 2005Co-Authors: J D Mezrich, David H Sachs, Parsia A Vagefi, Joren C Madsen, Louis C Benjamin, Jessica Sachs, Stuart L Houser, Kazuhiko YamadaAbstract:Background. The authors have examined the mechanism whereby co-transplantation of a kidney and heart from the same donor induces and maintains tolerance to both organs in miniature swine. Methods. Transplants were performed across a major histocompatibility complex class I mismatch, and recipients received cyclosporine for 12 days. Group 1 animals received heart transplants alone (n=5), and all other groups received both heart and kidney allografts. Group 2 animals received no further intervention (n=2). Group 3 animals underwent transplant nephrectomy 8 days after heart and kidney co-transplantation (n=2). Group 4 animals underwent transplant nephrectomy 100 days after co-transplantation (n=2). Skin grafts were placed on group 4 animals, on one group 3 animal, and on two animals from group 2. Group 5 animals underwent thymectomy 100 days after co-transplantation (n=4). Results. Group 1 animals developed cardiac allograft vasculopathy (CAV) and rejection. Group 2 animals never developed CAV and demonstrated in vitro donor-specific unresponsiveness. Group 3 animals suffered CAV and rejection. Group 4 animals developed CAV without concomitant donor-specific Cell-Mediated Lympholysis reactivity, interstitial rejection, or cessation of graft function. Skin grafts on group 3 and group 4 animals led to fulminant rejection of heart and skin grafts, in contrast to grafts on group 2 animals that had no in vivo effect. Group 5 animals developed CAV but no significant increase in interstitial infiltrates. Conclusions. Both the kidney and thymus were necessary for maintenance of tolerance to heart allografts.
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1 3 galactosyltransferase gene knockout miniature swine produce natural cytotoxic anti gal antibodies
Transplantation, 2004Co-Authors: F J M F Dor, Kazuhiko Yamada, Akira Shimizu, Yau Lin Tseng, Jane Cheng, K Moran, T M Sanderson, Courtney J Lancos, M Awwad, David H SachsAbstract:Background. The expression of galactoseal,3galactose (Gal) in pigs has proved a barrier to xenotransplantation Miniature swine lacking Gal (Gal -/- pigs) have been produced by nuclear transfer/embryo transfer. Methods. The tissues of five Gal -/- pigs of SLA dd haplotype (SLA dd ) were tested for the presence of Gal epitopes by staining with the Griffonia simplicifolia IB4 lectin. Their sera were tested by flow cytometry for binding of IgM and IgC to peripheral blood mononuclear Cells (PBMC) from wild-type (Gal +/+ ) SLA-matched pigs; serum cytotoxicity was also assessed. The Cellular responses of PBMC from Gal -/- swine toward Gal +/+ SLA-matched PBMC were tested by mixed leukocyte reaction and Cell-Mediated Lympholysis assays. Results. None of the tissues tested showed Gal expression. Sera from all five Gal -/- pigs manifested IgM binding tc Gal +/+ pig PBMC, and sera from three showed IgG binding. In all five cases, cytotoxicity to Gal +/+ Cells could b< demonstrated, which was lost after treatment of the sera with dithiothreitol, indicating IgM antibody-Mediated cytotoxicity. PBMC from Gal -/- swine had no proliferative or cytolytic T-Cell response toward Gal +/+ SLA-matchec PBMC. Conclusions. Gal -/- pigs do not express Gal epitopes and develop anti-Gal antibodies that are cytotoxic to Gal +/+ pig Cells. The absence of an in vitro Cellular immune response between Gal -/- and Gal +/+ pigs is related to their identica SLA haplotype and indicates the absence of immunogenicity of Gal in T-Cell responses. The model of Gal +/+ orgar transplantation into a Gal -/- SLA-matched recipient would be a valuable large animal model in the study of accommodation or B-Cell tolerance.
Akira Shimizu - One of the best experts on this subject based on the ideXlab platform.
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induction of cardiac allograft tolerance across a full mhc barrier in miniature swine by donor kidney cotransplantation
American Journal of Transplantation, 2013Co-Authors: Maria Lucia Madariaga, Sebastian Michel, G M La Muraglia, Masayuki Tasaki, Vincenzo Villani, Smita Sihag, James Gottschall, Evan A Farkash, Akira ShimizuAbstract:We have previously shown that tolerance of kidney allografts across a full major histocompatibility complex (MHC) barrier can be induced in miniature swine by a 12-day course of high-dose tacrolimus. However, that treatment did not prolong survival of heart allografts across the same barrier. We have now tested the effect of cotransplanting an allogeneic heart and kidney from the same MHC-mismatched donor using the same treatment regimen. Heart allografts (n = 3) or heart plus kidney allografts (n = 5) were transplanted into MHC-mismatched recipients treated with high-dose tacrolimus for 12 days. As expected, all isolated heart allografts rejected by postoperative day 40. In contrast, heart and kidney allografts survived for >200 days with no evidence of rejection on serial cardiac biopsies. Heart/kidney recipients lost donor-specific responsiveness in Cell-Mediated Lympholysis and mixed-lymphocyte reaction assays, were free of alloantibody and exhibited prolonged survival of donor, but not third-party skin grafts. Late (>100 days) removal of the kidney allografts did not cause acute rejection of the heart allografts (n = 2) and did not abrogate donor-specific unresponsiveness in vitro. While kidney-induced cardiac allograft tolerance (KICAT) has previously been demonstrated across a Class I disparity, these data demonstrate that this phenomenon can also be observed across the more clinically relevant full MHC mismatch. Elucidating the renal element(s) responsible for KICAT could provide mechanistic information relevant to the induction of tolerance in recipients of isolated heart allografts as well as other tolerance-resistant organs.
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tolerance and long lasting peripheral chimerism after allogeneic intestinal transplantation in mgh miniature swine
Transplantation, 2010Co-Authors: Yoshinori Ishikawa, Atsushi Hirakata, Adam Griesemer, Justin Etter, S Moran, Joshua Weiner, Akira Shimizu, Kazuhiko YamadaAbstract:Background and Objective. Clinical intestinal transplantation (Int-Tx) is limited by high rates of rejection, infection, and graft versus host disease. To improve clinical outcomes and eliminate the comorbidities associated with chronic immunosuppression, the induction of donor-specific tolerance to intestinal grafts is desirable, especially in the pediatric population. This study determined the ability of intestinal grafts to facilitate tolerance induction in major histo-compatibility complex (MHC)-inbred miniature swine. Methods. Seven MGH-miniature swine received heterotopic intestinal grafts, two across MHC-matched, minor-antigen disparities, three across a class I MHC disparity with 12 days of cyclosporine A, and two across a class I MHC disparity without an immunosuppressant. Chimerism was assessed by FACS analysis and immunohistochemistry. Cell-Mediated Lympholysis assays were used to assess antidonor responses. Results. Two animals receiving intestinal grafts without an immunosuppressant developed antidonor IgG in 14 days and rejected these completely. All other grafts were accepted with 12 days of cyclosporine A across both MHC-matched and MHC class I barriers. Cell-Mediated Lympholysis assays showed donor-specific unresponsiveness by day 30 across MHC class I barriers. Greater than 15% peripheral donor Cell chimerism persisted for more than 60 days after MHC-matched Int-Tx. Although less than 1.5% peripheral donor Cell chimerism was seen during the maintenance period after class I-mismatched Int-Tx, 5% to 10% myeloid chimerism was found in the peripheral blood 14 to 90 days after Int-Tx. FACS analysis demonstrated that 1% to 2% of lymphocytes in the graft mesenteric lymph nodes were CD4 + /CD25 high+ /Foxp3 + Cells. Conclusion. To our knowledge, this is the first demonstration of tolerance induction and persistence of chimerism in a large animal intestinal transplant model.
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linked suppression across an mhc mismatched barrier in a miniature swine kidney transplantation model
Journal of Immunology, 2008Co-Authors: Adam Griesemer, David H Sachs, John C Lamattina, Masayoshi Okumi, Justin Etter, Akira Shimizu, Kazuhiko YamadaAbstract:We have demonstrated previously that a 12-day course of FK506 permits the induction of tolerance to fully MHC-mismatched renal transplants in miniature swine. In the present study, we examined the mechanism of this tolerance by assessing the possibility that the survival of one-haplotype mismatched third-party kidneys might be prolonged via linked suppression. Ten SLA(d/d) miniature swine received fully MHC-mismatched renal allografts from SLA(c/c) donors with 12 days of FK506. Six animals received second SLA(c/c) kidneys without immunosuppression to confirm tolerance. Regulatory mechanisms were assessed by mixed lymphocyte reaction (MLR) and Cell-Mediated Lympholysis coculture assays and ELISA for regulatory cytokines. Linked suppression was investigated by transplanting SLA(a/c) or SLA(a/d) allografts into long-term tolerant recipients without immunosuppression. All recipients showed donor-specific unresponsiveness in standard Cell-Mediated Lympholysis and MLR assays. Tolerant Cells prestimulated with donor Ag and then cocultured with naive recipient MHC-matched Cells inhibited antidonor responses, confirming the presence of regulatory Cells. ELISA and MLR assays showed that TGF-beta2 was involved in mediating the suppression in vitro. SLA(a/d) renal allografts transplanted into tolerant recipients were rejected by postoperative day 8 (median, 7 days; range, 6-8). In contrast, SLA(a/c) allografts showed markedly prolonged survival (median, 52 days; range, 28-78; p = 0.0246), suggesting linked suppression. Animals not challenged with a second donor-matched graft did not manifest linked suppression consistent with in vitro data showing that re-exposure to tolerated Ags is important for generation of regulatory Cells. To our knowledge, these data represent the first evidence of linked suppression across fully MHC-mismatched barriers in a large animal model.
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1 3 galactosyltransferase gene knockout miniature swine produce natural cytotoxic anti gal antibodies
Transplantation, 2004Co-Authors: F J M F Dor, Kazuhiko Yamada, Akira Shimizu, Yau Lin Tseng, Jane Cheng, K Moran, T M Sanderson, Courtney J Lancos, M Awwad, David H SachsAbstract:Background. The expression of galactoseal,3galactose (Gal) in pigs has proved a barrier to xenotransplantation Miniature swine lacking Gal (Gal -/- pigs) have been produced by nuclear transfer/embryo transfer. Methods. The tissues of five Gal -/- pigs of SLA dd haplotype (SLA dd ) were tested for the presence of Gal epitopes by staining with the Griffonia simplicifolia IB4 lectin. Their sera were tested by flow cytometry for binding of IgM and IgC to peripheral blood mononuclear Cells (PBMC) from wild-type (Gal +/+ ) SLA-matched pigs; serum cytotoxicity was also assessed. The Cellular responses of PBMC from Gal -/- swine toward Gal +/+ SLA-matched PBMC were tested by mixed leukocyte reaction and Cell-Mediated Lympholysis assays. Results. None of the tissues tested showed Gal expression. Sera from all five Gal -/- pigs manifested IgM binding tc Gal +/+ pig PBMC, and sera from three showed IgG binding. In all five cases, cytotoxicity to Gal +/+ Cells could b< demonstrated, which was lost after treatment of the sera with dithiothreitol, indicating IgM antibody-Mediated cytotoxicity. PBMC from Gal -/- swine had no proliferative or cytolytic T-Cell response toward Gal +/+ SLA-matchec PBMC. Conclusions. Gal -/- pigs do not express Gal epitopes and develop anti-Gal antibodies that are cytotoxic to Gal +/+ pig Cells. The absence of an in vitro Cellular immune response between Gal -/- and Gal +/+ pigs is related to their identica SLA haplotype and indicates the absence of immunogenicity of Gal in T-Cell responses. The model of Gal +/+ orgar transplantation into a Gal -/- SLA-matched recipient would be a valuable large animal model in the study of accommodation or B-Cell tolerance.
M. Shearer - One of the best experts on this subject based on the ideXlab platform.
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Brief Definitive Report REGULATION OF T-Cell-Mediated Lympholysis BY THE MURINE MAJOR HISTOCOMPATIBILITY COMPLEX II. Controi of Cytotoxic Responses to Trinitrophenyl-K and-D Self Products by H-2K- and H-2D-Region Genes
2013Co-Authors: B. Levy, Ann Gene, M. ShearerAbstract:Genetic regulation of Cell-Mediated Lympholysis (CML) responses to antigenic determinants that are recognized in association with H-2K- and H-2D-coded self structures have been reported for trinitrophenyl (TNP)-modified Cells (TNP-self) (1) and viral-infected (2) Cells, as well as to Cells expressing the sex-linked H-Y antigen (3). Multi-gene (Ir gene) control of CML to the H-Y antigen has been demonstrated to map within the /-region of H-2 (4, 5). Other /r-like genetic effects have been reported in which preferential CML responses have been observed against TNP-self Cells and viral-infected Cells. In this type of immune regulation, the haptenic or viral determinants are recognized predominantly in association with either the K- or the D-region products (6). Similar findings have been recently observed in the CML response against influenza virus-infected human leukocytes (7). Recent investigations involving the generation of cytotoxic responses to TNP-self syngeneic Cells have demonstrated the uniqueness of K k products in this system. First, preferential cytotoxic responses against Kk-TNP antigens were observed, regardless of the accompanying D-region allele present on the stimulating population (6, 8, 9)
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Brief Definitive Report MIXED LYMPHOCYTE REACTIVITY AND Cell-Mediated Lympholysis TO TRINITROPHENYL-MODIFIED AUTOLOGOUS LYMPHOCYTES IN C57BL/10 CONGENIC AND B10.A RECOMBINANT MOUSE STRAINS
2013Co-Authors: M. Shearer, Eugene C Lozner, Terry G RehnAbstract:Cell-Mediated Lympholysis (CML) to trinitrophenyl (TNP)-modified autologous splenic lymphocytes has been recently reported in the mouse (1). Both the sensitization and effector phases of this phenomenon were shown to be T-Cell Mediated. Effector Cell specificity studies indicated that modification of the target Cells is a necessary but insufficient requirement for cytolysis, and suggested that altered Cell surface components controlled by genes mapping in the mouse major histocompatibility H-2 complex (MHC) are important in the specificity of the cytotoxic reaction (1). In allogeneic models the generation of cytotoxic effector Cells has been shown to be preceded or accompanied by immunogen-induced proliferation of responding lymphocytes, i.e. a mixed lymphocyte reaction (MLR) (2-5), although the generation of effectors may not necessarily always be the consequence of extensive Cell proliferation (5). If the induction of cytotoxic effector lymphocytes by modified syngeneic spleen Cells is characteristic of sensitization with Cellular alloantigens, one would expect to find that sensitization with TNP-modified autologous Cells would also induc
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Brief Definitive Report Cell-Mediated Lympholysis TO H-2-MATCHED TARGET CellS MODIFIED WITH A SERIES OF NITROPHENYL COMPOUNDS
2013Co-Authors: G. Rehn, John K. Inman, Any Gene, M. ShearerAbstract:At least four different assays have been used to investigate the fine specificity of lymphocytes considered to possess T-Cell characteristics. These methods include delayed hypersensitivity reactions in guinea pigs (1-4), in vitro proliferation of peritoneal lymphocytes in guinea pigs (3, 4) and mice (5), macrophage migration inhibition by lymphocytes (4), and the generation of cytotoxic T lymphocytes to viral-infected (6-9) or chemically modified (10, 11) autologous Cells. In the latter system, two basic models for the cytotoxic T-Cell receptor have been proposed (12, 13): one involving a single receptor by which the lymphocyte recognizes the infectious or modifying agent and self-H-2 products as a single antigenic unit; and the other, in which the T lymphocyte expresses two distinct receptors, one for ~'hapten " and the second for autologous H-2 products. By challenging T lymphocytes from guinea pigs immunized with hapten coupled to mycobacteria with a series of related haptens and carriers, Janeway and coworkers found that T Cells recognized neither hapten nor carrier alone, but specificities involving both moieties (3, 4). An earlier report demonstrated that there was no detectable cross-reactivity within the same mouse strain between cytotoxic lymphocytes generated by sensitization with autologous Cells modified with either trinitrobenzene sulfonate (TNBS) or N-(3-nitro-4-hydroxy-5-iodophenylacetyl)-f~-alanylglycylglycyl (NIP-AGG) acyl azide (11). The present study further defines the fine specificity of Cell-Mediated Lympholysis (CML) reactions against chemically modified autologous Cells by comparing the specificity of effector Cells generated by sensitization with autologous lymphocytes from C57BL/10 mice modified with the acyl azides of NIP-AGG, NP-AGG, NIP, TNP-AGG, and with TNBS (see Materials and Methods for explanation of abbreviations)
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Brief Definitive Report Cell-Mediated Lympholysis OF TRINITROPHENYL-MODIFIED AUTOLOGOUS LYMPHOCYTES Confirmation of Genetic Control of Response to Trinitrophenyl-Modified H-2 Antigens by the Use of Anti-H-2 and Anti-Ia Antibodies
2013Co-Authors: Anne-marie Schmitr-verhulst, David H Sachs, M. ShearerAbstract:The in vitro induction of T-Cell-Mediated Lympholysis (CML) to trinitrophenyl (TNP)modified autologous spleen Cells has been demonstrated in the mouse (1). Lysis of modified splenic target Cells was obtained when there was K or D serological region homology between the target Cells and the Cells used in the sensitizing phase (2, 3). Experiments using F ~ responding lymphocytes sensitized and assayed with TNP-modified parental Cells indicated that homology between effector and target Cells was not sufficient to obtain lysis, but that the homology required was either between modified stimulating and modified target Cells, or among responding, modified stimulating and modified target Cells (2). These findings are compatible with the hypothesis that TNP is modifying Cell surface components controlled by the K and D serological regions of the major histocompatibility complex, and that the responding lymphocytes are reacting against these new antigenic specificities. Earlier studies have shown that sensitization of B10.A responding lymphocytes with TNP-modified autologous spleen Cells generated effector Cells which lysed TNP-modified K-end-matched target Cells, but not TNP-modified D-end-matched targets (2, 4). Thi
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Failure to Recognize
2013Co-Authors: Sulfonate-modified Syngeneic Cells, Cell Surface-bound, Trinitrophenyl Dextran, A. Henkart, Anne-marie Schmitt-verhulst, M. ShearerAbstract:Cell-Mediated Lympholysis (CML) 1 has been generated in vitro against trinitrophenyl (TNP)-modified syngeneic murine spleen Cells (1). The specificity of the effectors generated is such that the stimulater and target Cells must beth be modified by the same agent (2, 3)1 and must also express the same H-2K and/or H-2D haplotypes (4, 5). In previous studies of the specificity of the CML effecters directed against TNP self, the modifying agents were coupled to Cell surface proteins via covalent linkage, primarily to the amino groups of lysines (6). The present report describes experiments in which TNP stearoyl dextran was inserted into the lipid bilayer of mouse spleen Cells (used as sensitizing Cells) and lymphoid tumor Cells (used as target Cells) for the generation of effectors directed against self-modified Cells. The results indicate that when quantitatively equivalent amounts of TNP are present on the Cell surface either in the form of TNP stearoyl dextran (TSD) or as a result of direct covalent modification of the Cell surface with trinitrobenzene sulfonate (TNBS), only the latter is immunogenic for the generation of a TNP self CML. Furthermore, the TSDmodified Cells do not serve either as lysable targets or as inhibiting Cells of effecters generated by sensitization with TNBS-modified syngeneic Cells. Materials and Methods Mice. The mice used in the experiments were males 6-9 wk of age. Both the B10.A and B10.BR, as well as the AKR/J, mice were purchased from The Jackson Laboratory, Bar Harbor
Maria Lucia Madariaga - One of the best experts on this subject based on the ideXlab platform.
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effects of lung cotransplantation on cardiac allograft tolerance across a full major histocompatibility complex barrier in miniature swine
American Journal of Transplantation, 2016Co-Authors: Maria Lucia Madariaga, Philip J Spencer, Sebastian Michel, G M La Muraglia, M J Oneil, E C Mannon, C Leblang, Ivy A Rosales, Robert B Colvin, David H SachsAbstract:A 12-day course of high-dose tacrolimus induces tolerance of major histocompatibility complex-mismatched lung allografts in miniature swine but does not induce tolerance of heart allografts unless a kidney is cotransplanted. To determine whether lungs share with kidneys the ability to induce cardiac allograft tolerance, we investigated heart-lung cotransplantation using the same induction protocol. Hearts (n = 3), heart-kidneys (n = 3), lungs (n = 6), and hearts-lungs (n = 3) were transplanted into fully major histocompatibility complex-mismatched recipients treated with high-dose tacrolimus for 12 days. Serial biopsy samples were used to evaluate rejection, and in vitro assays were used to detect donor responsiveness. All heart-kidney recipients and five of six lung recipients demonstrated long-term graft survival for longer than 272 days, while all heart recipients rejected their allografts within 35 days. Tolerant recipients remained free of alloantibody and showed persistent donor-specific unresponsiveness by Cell-Mediated Lympholysis/mixed-lymphocyte reaction. In contrast, heart-lung recipients demonstrated rejection of both allografts (days 47, 55, and 202) and antidonor responsiveness in vitro. In contrast to kidneys, lung cotransplantation leads to rejection of both heart and lung allografts, indicating that lungs do not have the same tolerogenic capacity as kidneys. We conclude that Cells or Cell products present in kidney, but not heart or lung allografts, have a unique capacity to confer unresponsiveness on cotransplanted organs, most likely by amplifying host regulatory mechanisms.
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induction of cardiac allograft tolerance across a full mhc barrier in miniature swine by donor kidney cotransplantation
American Journal of Transplantation, 2013Co-Authors: Maria Lucia Madariaga, Sebastian Michel, G M La Muraglia, Masayuki Tasaki, Vincenzo Villani, Smita Sihag, James Gottschall, Evan A Farkash, Akira ShimizuAbstract:We have previously shown that tolerance of kidney allografts across a full major histocompatibility complex (MHC) barrier can be induced in miniature swine by a 12-day course of high-dose tacrolimus. However, that treatment did not prolong survival of heart allografts across the same barrier. We have now tested the effect of cotransplanting an allogeneic heart and kidney from the same MHC-mismatched donor using the same treatment regimen. Heart allografts (n = 3) or heart plus kidney allografts (n = 5) were transplanted into MHC-mismatched recipients treated with high-dose tacrolimus for 12 days. As expected, all isolated heart allografts rejected by postoperative day 40. In contrast, heart and kidney allografts survived for >200 days with no evidence of rejection on serial cardiac biopsies. Heart/kidney recipients lost donor-specific responsiveness in Cell-Mediated Lympholysis and mixed-lymphocyte reaction assays, were free of alloantibody and exhibited prolonged survival of donor, but not third-party skin grafts. Late (>100 days) removal of the kidney allografts did not cause acute rejection of the heart allografts (n = 2) and did not abrogate donor-specific unresponsiveness in vitro. While kidney-induced cardiac allograft tolerance (KICAT) has previously been demonstrated across a Class I disparity, these data demonstrate that this phenomenon can also be observed across the more clinically relevant full MHC mismatch. Elucidating the renal element(s) responsible for KICAT could provide mechanistic information relevant to the induction of tolerance in recipients of isolated heart allografts as well as other tolerance-resistant organs.