Association between HLA-B antigens and acute graft-versus-host disease.

130 patients with severe aplastic anaemia, conditioned with high-dose cyclophosphamide, showed sustained engraftment of marrow from HLA-identical siblings. Most patients (55%) had no acute graft-versus-host disease (GVHD), 11% had transient grade I, and 34% had moderate to severe (grades II-IV) acute GVHD. The relation between the donors' (and the patients') HLA antigens and the incidence of grades I-IV acute GVHD was explored. There was no association with HLA-A antigens, but a significant correlation with HLA-B antigens. Patients with HLA-B18 had an estimated acute GVHD incidence nearly three times that of other patients, whereas the incidence in the presence of HLA-B8 or HLA-Bw35 was estimated to be about half that in the absence of these alleles.