J. H. Quisenberry

RELATION OF BLOOD GROUP GENOTYPES TO THERAPEUTIC EFFECTIVENESS OF BONE MARROW TRANSPLANTS FOLLOWING X-IRRADIATION.

Summary Chicks of known blood group genotype and parentage produced from a partially inbred line of Single Comb White Leghorns were subjected to 1800 r of discontinuous X-irradiation when approximately 21 days of age. Irradiation was administered at the rate of 16.5 r/minute in increments of 300 r interspersed with 40-minute intervals without irradiation. Immediately following irradiation hosts received intravenous injections of bone marrow homogenate obtained from sacrificed donors having various degrees of blood group genotype relationship with the respective hosts. Thirty-day post-irradiation mortality of hosts receiving transplants from donors of a different breed or of the same breed but of incompatible A, B, C and D blood group genotype was essentially the same as the irradiated controls receiving no bone marrow transplants. These groups averaged 7.3% survival as opposed to 66.3% survival for hosts receiving transplants from donors of identical blood type. When donor and host were full-sibs in addition to having compatible blood type the survival rate increased to 83.8%. Incompatibility of donor and host at the A, C and D blood group loci resulted in essentially the same levels of mortality; the average being 42.42%. This is in contrast to 86.67% mortality of hosts having donors of incompatible B system genotype. Hemagglutination tests showed the majority of the hosts to be circulating red cells of the host-type by 10 days post-irradiation, a mixture of donor and host types from 15 days through 60 days post-irradiation and host-type by 70 days post-irradiation. These tests also showed 38.5% of the hosts to be circulating only donor-type cells by 40 days post-irradiation and one individual still exhibited only donor-type cells at 80 days. Donor-type cells were detected in 100% of the hosts having donors of incompatible A, C or D blood type. Where incompatibility at the B locus was involved, only one host was found to be circulating donor-type cells during the post-irradiation period.