Prediction by a modified mixed leukocyte reaction assay of graft-versus-host disease and graft rejection after allogeneic bone marrow transplantation

In this report we describe a modified, sensitive MLR test that appears to detect fine antigenic disparities between HLA-identical siblings confirmed as such by serology and the standard MLR test. In a group of 40 consecutive allogeneic bone marrow transplants, reactivity detected by the modified MLR test correlated with the development of rejection of matched marrow grafts and onset of acute graft vs. host disease (aGVHD). Thus, 13/15 positively reacting patient/donor pairs developed one of these complications (P<0.001), while only 2/25 developed aGVHD in the negatively reacting group. This test may be useful for selecting the most compatible donor when several potential donors are available.