Bu1 Products

Chicken Bu-1, a product of the Bu-1a and Bu-1b alleles, is a type I transmembrane glycosylated, disulfide-linked homodimer. MAb AV20 recognizes a monomorphic determinant on the Bu-1 B cellassociated alloantigens of both RPL 6(3) (Bu-1a) and 7(2) (Bu-1b) lines of inbred chickens. The antibody also identifies B cells in partially inbred birds. Bu-1 is found on 85-90% of bursal cells, 2-8% of thymocytes, 15-27% of spleen cells, and 2-18% of peripheral blood cells. It is also expressed on subsets of macrophages and monocytes, but not on granulocytes, erythrocytes or thrombocytes. (1-2) MAb AV20 does not cross react with turkey cells when analyzed by immunofluorescent staining and flow cytometry. (3)