Isolation and characterization of two new functional subtypes of HLA‐B35

Human minor histocompatibility antigen-specific, HLA-B*3501-restricted cytotoxic T-cell clones were assayed on a panel of 25 different target cells previously typed by serology as HLA-B35. Cells from 6 donors were not killed and cells from 2 of these were further studied by molecular cloning to characterize their HLA class I alleles. Two new HLA-B35 subtypes were identified. The sequence of one of them differs from B*3501 by one nucleotide change at codon 156, replacing a Leu for an Arg. The sequence of the other new subtype also shows a single nucleotide change compared to B*3501, with Gly-->Val substitution at residue 16. With these new variants, the allelic complexity of HLA-B35 extends now to eight subtypes.