Effectiveness of a regional bone marrow donor program.

Because many potential bone marrow transplant patients lack HLA-matched siblings, there is growing interest in carrying out transplantations using matched, unrelated volunteer donors. We developed a local registry of 2147 informed donors who consented to be listed in the Bone Marrow Donor Registry. This registry was used to carry out 420 donor searches for 351 patients. The initial computer search involved matching for HLA-A and HLA-B locus antigens only because most donors had not been typed for HLA-DR antigens. Depending on the degree of HLA-A and HLA-B antigen mismatching allowed, suitably matched (HLA-DR-identical, mixed lymphocyte culture nonreactive) donors were located for 6% to 16% of patients. This resulted in 13 bone marrow transplants. This study shows that a small, local bone marrow donor registry can locate donors for a few patients; however, a large network involving an expanded number of donors will be necessary to allow an extensive evaluation of unrelated bone marrow transplantation.