Articles tagged "B cells"

2020 American Transplant Congress
Thymic B Cells: A Means to Control Regulatory Tolerance
C. LeGuern¹, S. Germana¹, N. Feeney¹, Z. Wang², N. Tanimine¹, C. Huang³, C. Rickert¹, J. Markmann¹
¹Surgery, Center for Transplantation Sciences, Massachusetts General Hospital, Charlestown, MA, ²University of Colorado Denver, Aurora, CO, ³Surgery, University of Colorado Denver, Aurora, CO
*Purpose: Therapies involving CD4 regulatory T cells (Tregs) are promising approaches to mitigate graft rejection and autoimmunity. Understanding of the activation mechanisms that initiate Treg…
2020 American Transplant Congress
Characterization of Non HLA Antibodies in Kidney Transplant Recipients
S. Rodriguez Ramirez¹, S. Clotet-Freixas¹, C. Mcevoy¹, M. Kotlyar², I. Jurisica², A. Chruscinski¹, A. Konvalinka³
¹Kidney Transplant, Toronto General Hospital Research Institute, Multi-Organ Transplant Program, University Health Network, Toronto, ON, Canada, ²Kidney Transplant, Krembil Research Institute, University Health Network, Toronto, ON, Canada, ³Kidney Transplant, Department of Medicine, Division of Nephrology, University Health Network, Toronto, ON, Canada
*Purpose: Antibody mediated rejection (AMR) causes more than 60 percent of late graft failures in kidney transplants (KT). Although antiHLA donor specific antibodies are the…
2020 American Transplant Congress
Allograft Repopulating Recipient B Cells after Human Intestinal Transplantation and Their Association with Donor Specific Antibody Secretion and Rejection
E. Waffarn¹, J. Fu¹, K. Frangaj¹, W. Meng², A. M. Rosenfeld², M. Li³, K. Rodgers¹, R. Vasilescu³, E. T. Luning Prak², A. Griesemer¹, T. Kato⁴, M. Martinez⁵, M. Sykes¹
¹Columbia Center for Translational Immunology, Department of Medicine, Columbia University, New York, NY, ²Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, ³Department of Pathology, Columbia University, New York, NY, ⁴Department of Surgery, Columbia University, New York, NY, ⁵Department of Pediatrics, Columbia University, New York, NY
*Purpose: Alloantibodies produced by recipient B cells are associated with rejection after intestinal transplantation (ITx) and negatively impact patient and graft survival. However, the dynamics…
2020 American Transplant Congress
Novel Treatment of Acute Antibody-Mediated Rejection in a Nonhuman Primate Model of Kidney Allotransplantation
R. Schmitz¹, Z. W. Fitch¹, A. Y. Choi¹, M. Manook¹, J. Yoon¹, J. D. Lambris², J. Kwun¹, S. J. Knechtle¹
¹Department of Surgery, Duke University Medical Center, Durham, NC, ²Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA
*Purpose: One third of sensitized, HLA-incompatible transplant recipients experience acute antibody mediated rejection (AMR) with limited treatment options. We tested a novel treatment strategy for…
2020 American Transplant Congress
The Effect of B Cell Depletion Therapies on Preformed Xenoantibodies in Transplant Recipient
S. Yeh¹, N. A. Wilson², A. Djamali², R. Redfield³
¹Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, WI, ²Medicine/Nephrology, University of Wisconsin-Madison, Madison, WI, ³Surgery, University of Wisconsin-Madison, Madison, WI
*Purpose: To assess the effect of B cell depletion therapies on preformed xenoantibodies in transplant recipient. Preformed xenoantibodies are a significant barrier to successful xenotransplantation.…
2020 American Transplant Congress
Ex Vivo Generated Regulatory B Cells Can Suppress Donor-Specific CD4 T Cells Proliferation In Vivo
G. Huai¹, K. M. Lee¹, Q. Fu¹, K. Deng¹, N. J. Feeney¹, C. Leguern¹, N. Tanimine¹, C. G. Rickert¹, S. Deng², J. F. Markmann¹
¹Center for Transplantation Sciences, Massachusetts General Hospital, Harvard Medical School, Boston, MA, ²Organ Transplantation Center, Sichuan Provincial People's Hospital and School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
*Purpose: B cells expanded in vitro via TLR9 agonist CpG and activated by LPS, PMA and ionomycin have been previously denoted “TLR-Bregs” by our team.…
2020 American Transplant Congress
Transient Cd4+ T Cell and Cd20+ B Cell Depletion Leads to Prolonged Pig-To-Primate Kidney Xenograft Survival
B. P. Lovasik¹, A. J. Matar¹, D. A. Faber¹, D. V. Mathews¹, C. Breeden¹, S. C. Kim¹, A. J. Tector², A. B. Adams¹
¹Emory University School of Medicine, Atlanta, GA, ²University of Miami, Miami, FL
*Purpose: “Delayed” antibody-mediated xenograft rejection is the one of the most important obstacle to clinical application of pig organ xenografts. The aim of this study…
2020 American Transplant Congress
Splenectomy Impedes B Cell Infiltration Associated with Rejection of Neonatal Porcine Islet Xenografts
Z. W. Fitch, M. Song, R. Schmitz, F. Leopardi, M. Ribeiro, A. Miller, G. Devi, B. Collins, X. Luo, A. D. Kirk
Duke University, Durham, NC
*Purpose: Xenotransplantation has historically been frustrated by antibody-mediated rejection. Splenectomy has shown efficacy in mediating humoral immunity. We hypothesized that adding splenectomy to a clinically…
2020 American Transplant Congress
Characterization of a Novel CD8⁺ B Cell Subset in Monkeys Tolerant of Heart Allografts
J. A. Morrissette¹, K. Pruner¹, S. Lee¹, J. Paster¹, W. Sommer¹, J. O¹, I. Hanekamp¹, P. Sage², G. Benichou¹, J. C. Madsen³
¹Center for Transplantation Sciences, Department of Surgery, Massachusetts General Hospital, Boston, MA, ²Transplantation Research Center, Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, ³Center for Transplantation Sciences, Division of Cardiac Surgery, Department of Surgery, Massachusetts General Hospital, Boston, MA
*Purpose: We have previously reported that transient mixed hematopoietic chimerism induced via donor bone marrow transplantation can achieve tolerance to cardiac allografts in non-human primates…
2020 American Transplant Congress
Early Prediction of Human Renal Allograft Rejection (AR) by Inflammatory Transitional B Cells
A. Cherukuri¹, A. Sharma¹, R. Mehta¹, H. Sundaram¹, A. Salama², D. Rothstein¹
¹Starzl Transplantation Institute, UPMC, Pittsburgh, PA, ²UCL, London, United Kingdom
*Purpose: Early prediction of AR within the 1st post-transplant year could identify at-risk patients for targeted therapeutic interventions to mitigate risk and improve outcomes.*Methods: In…