title: Molecular analysis of the HLA-DR5 haplotype.
abstract: A panel of eleven HLA-DR5 homozygous lymphoblastoid cell lines was investigated for structural heterogeneity on the product level. HLA class II antigens were isolated by immunoprecipitation with different anti-class II monoclonal antibodies and separated by two-dimensional (2-D) gel electrophoresis. As a result, three distinct DRB1, one commonly expressed DRB3, and two distinct DQ gene products could be identified that combined to four different haplotypes associated with HLA-DR5. A hitherto serologically undetected split of HLA-DRw11 was presented by three cell lines. HLA-DRw11 and HLA-DRw12 were found to be related allospecifities that differ only in their DRB1 locus products, but are closely associated with the supertypic DRB3 allele HLA-DRw52b and with HLA-DQw7. The DRB3 alleles HLA-DRw52a and DRw52c were not detected in our cell line panel, indicating that these supertypic determinants are in negative linkage disequilibrium with HLA-DR5. Our data suggest that intra HLA-DR/DQ crossing-over events contribute to the development of the HLA class II polymorphism. Evidence is presented that the T cell defined HLA-D allospecifities are commonly determined by DRB1 and DQ gene products.
authors.affiliation: Department of Transfusion Medicine, University of Ulm, FRG.
authors.forename: M
authors.initials: M
authors.lastname: Ballas
authors.forename: A
authors.initials: A
authors.lastname: Madrigal
authors.forename: R
authors.initials: R
authors.lastname: Bontrop
authors.forename: M J
authors.initials: MJ
authors.lastname: Giphart
authors.forename: J
authors.initials: J
authors.lastname: Bodmer
authors.forename: S F
authors.initials: SF
authors.lastname: Goldmann
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000911:Antibodies, Monoclonal; D001402:B-Lymphocytes / Q000032:analysis; D001483:Base Sequence; D002460:Cell Line; D015180:Electrophoresis, Gel, Two-Dimensional; D006681:HLA-D Antigens / Q000032:analysis; D015805:HLA-DR5 Antigen / Q000235:genetics*; D006239:Haplotypes; D006801:Humans; D011233:Precipitin Tests
chemical_list: D000596:Amino Acids; D000911:Antibodies, Monoclonal; D006681:HLA-D Antigens; D015805:HLA-DR5 Antigen