Biology of blood and marrow transplantation : journal of the American Society for Blood and Marrow Transplantation
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Biol. Blood Marrow Transplant. · Aug 2005
Clinical TrialBusulfan/melphalan/antithymocyte globulin followed by unrelated donor cord blood transplantation for treatment of infant leukemia and leukemia in young children: the Cord Blood Transplantation study (COBLT) experience.
A non-total body irradiation-containing preparative regimen was studied in young children (<4 years old) undergoing unrelated donor cord blood transplantation as part of the Cord Blood Transplantation trial for the treatment of acute lymphoblastic leukemia (n = 14), acute myeloid leukemia (n = 13), undifferentiated leukemia (n = 1), juvenile myelomonocytic leukemia (n = 2), and myelodysplastic syndromes (n = 2). Donor/recipient HLA matching based on low-/intermediate-resolution molecular typing for HLA-A and -B and high-resolution HLA-DRB1 typing was 5/6 or 6/6 (n = 21) or 4/6 (n = 11). The preparative therapy consisted of busulfan, melphalan, and antithymocyte globulin, with cyclosporine and corticosteroids for graft-versus-host disease (GVHD) prophylaxis. ⋯ The CINC estimate of relapse was 0.31 (95% CI, 0.16-0.47) at 2 years. With a median follow-up of 27.8 months (range, 23.4-46.7 months), the probability of survival at 1 year was 0.47 (95% CI, 0.30-0.64). A preparative regimen containing a busulfan/melphalan/antithymocyte globulin preparative regimen is well tolerated in the setting of unrelated donor cord blood transplantation for childhood leukemia and can serve as a platform preparative regimen for intensifying host immunosuppression and antileukemic therapy to allow for improved engraftment and improved relapse-free survival.
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Biol. Blood Marrow Transplant. · Aug 2005
Effector cells derived from host CD8 memory T cells mediate rapid resistance against minor histocompatibility antigen-mismatched allogeneic marrow grafts without participation of perforin, Fas ligand, and the simultaneous inhibition of 3 tumor necrosis factor family effector pathways.
Reduced-intensity conditioning regimens for transplant recipients have heightened awareness of immunologic resistance to allogeneic bone marrow transplants (BMT). Although T cell-mediated cytotoxicity has been assumed to play a role in the resistance against donor allogeneic hematopoietic stem and progenitor cell grafts, several studies have reported relatively unimpaired resistance by recipients who lack perforin, Fas ligand (FasL), and other cytotoxic mediators. This study compared the early kinetics of T cell-mediated resistance in B6 (H2b) cytotoxically normal versus deficient recipients after transplantation with major histocompatibility complex-matched, minor histocompatibility antigen (MiHA)-mismatched allogeneic marrow grafts. ⋯ In contrast, low or absent colony-forming unit levels were detected in allogeneic recipients, including those that lacked perforin and FasL and that received anti-TWEAK, anti-tumor necrosis factor-related apoptosis-inducing ligand, and anti-TL1A monoclonal antibodies. These findings extend previous observations by demonstrating the existence of a rapidly effected resistance pathway mediated by memory CD8 effector T cells independent of the 2 major pathways of cytotoxicity. Together with previous findings, these results support the notion that effector cells derived from memory CD8 T-cell populations can mediate strong resistance against donor allogeneic MiHA-disparate hematopoietic engraftment by using a mechanism that is independent of the contribution of perforin, FasL, and the known death ligand receptor pathways.