Therapeutic strategy for post-transfusion graft-vs.-host disease

An effective treatment for post-transfusion graft-vs.-host disease (PT-GVHD), a fatal complication of blood transfusion, has not yet been identified. In this review, we propose a treatment for PT-GVHD based on the mechanism of its onset. First, we briefly review the findings that PT-GVHD is induced by cytotoxic T-lymphocyte (CTL)-mediated tissue injuries through the Fas/Fas ligand system, the perforin/granzyme system, and alloantigen-specific antibodies, as well as through inflammatory cytokines. Secondly, we emphasize the usefulness of a serine protease inhibitor for the inhibition of CTL-mediated cytotoxicity in the earlier stages of onset. Subsequent administration of methylprednisolone and 2-chlordeoxyadenosine is recommended for elimination of the donor's lymphocytes. The usefulness of chloroquine for the suppression of CTL activity and the production of tumor necrosis factor as well as the efficiency of pentoxyfylline for the suppression of the production of tumor necrosis factor are also discussed. Therapeutic strategies for PT-GVHD should also be useful for treating acute GVHD secondary to allogeneic bone marrow transplantation, and to prevent the host's rejection of transplanted organs as well as tissue damage in autoimmune diseases.