ABO-incompatible marrow transplants.

We analyzed data from 81 ABO-incompatible marrow transplants performed between 1972 and 1980. Patients with high anti-red blood cell antibody levels pretransplant had a significantly increased probability of antibody return post-transplant. This was true for IgG and for IgM as independent variables. However, the return of antibody post-transplant had no effect on engraftment, survival, or blood product requirements posttransplant. Patients who received ABO-incompatible marrow had a similar time to engraftment, survival, and incidence of rejection and graft-versus-host disease as patients receiving ABo-compatible transplants. Neither pretransplant treatment regimen nor the development of graft-versus-host disease had an effect on post-transplant antibody levels. ABO-incompatible marrow transplants can be performed with no greater morbidity or mortality than ABO-compatible grafts. The procedures for antibody removal may be useful in other organ transplant settings.