Treatment of post transfusion graft-versus-host disease.

Background and Objectives: In Japan, so many cases of post-transfusion graft-versus-host disease (PT-GVHD) have been reported, and no effective treatment has been reported. Materials and Methods: Results: Totally 61 cases of PT-GVHD have been collected, and their background were analyzed. A serine protease inhibitor, nafamostat mesilate(N.M.) was examined as a drug for treatment of PT-GVHD using 4 patients. Results: N.M. was confirmed to inhibit cytotoxic activities of established cytotoxic T cell (CTL) clones in vitro. Simultaneously it was confirmed that fever and skin rash disappeared and liver function tests were normalized soon after the administration of N.M. in all four cases. Leukopenia and thrombocytopenia simultaneously improved. Conclusion: The effects of N.M. seem to be limited to inhibit cytotoxic activity of CTL. In addition to this drug, how to remove the CTL from the patients will be the essentially important theme for the future.