Structural analyses define an additional H-2D region class I antigen that is expressed by a variant mouse strain.
The genetic complexity of the H-2D region includes haplotype disparities in apparent gene and product number. To probe the genetic basis of this complexity, the products of two independently derived mouse strains (STU and B10.SAA48) that express Dw3 antigens were compared. Serologic, fluorometric and peptide map comparisons were made using monoclonal antibodies. Although both STU and B10.SAA48 mice were found to express indistinguishable Dw3 molecules, only B10.SAA48 mice were found to express an additional antigen designated Lw3. Several lines of evidence are presented that suggest the gene encoding Lw3 maps to the D region. Furthermore peptide map comparisons of Dw3 with Lw3 molecules implied that they are products of separate genes; but Dw3 and Lw3 molecules were found to be more homologous to each other than Dd and Ld molecules are to each other. Inter-haplotype comparisons of Dw3 and Lw3 molecules with other D region molecules showed no striking homologies to Dd, Ld or eight other molecules compared. However, both Dw3 and Lw3 molecules were found to be unexpectedly homologous to the Ddx and Dw25 molecules, thus defining another family of structurally related D region antigens. This so called Dw3-family was found to be quite distinct from the previously defined Ld-family of molecules, since no joint members were found. The results of these studies of Dw3 encoded antigens are discussed as evidence for intra-D region recombination or mutation.
D000818:Animals; D000911:Antibodies, Monoclonal; D011232:Chemical Precipitation; D006183:H-2 Antigens / Q000032:analysis* / Q000235:genetics* / Q000276:immunology; D006239:Haplotypes; D064532:Histocompatibility Antigen H-2D; D051379:Mice; D008815:Mice, Inbred Strains; D010449:Peptide Mapping; D013050:Spectrometry, Fluorescence
D000911:Antibodies, Monoclonal; D006183:H-2 Antigens; D064532:Histocompatibility Antigen H-2D