Polymorphisms within the HLA-DRw6 haplotype. III. DQα and DQβ polymorphism associated with HLA-D

Abstract

We have studied HLA-DQ encoded antigens from HLA-DRw6 homozygous cells and analyzed the DQ region at the DNA level. HLA-DQ molecules were isolated from EBV transformed B-cell lines and analyzed for DQα and DQβ polymorphisms. From the same set of cells, DNA was isolated and analyzed for RFLP. Polymorphism could be detected by both techniques, i.e., on the protein level and on the DNA. The variation in pI of the DQα and β chains correlated with the polymorphism as detected by HTC typing, as did the variation in molecular weight of the bands hybridizing to DQ specific cDNA probes; identical patterns were detected for cells of one HLA-D specificity and different patterns for different HLA-D types. Additionally, DQ reactive PLT reagents were raised against DRw6 positive cells. Panel studies revealed that these DQ reactive proliferative T cells can discriminate between the polymorphic DQ antigens on cells with different HLA-D specificities.