Human B cells alloantigens; separation from other membrane molecules by affinity chromatography.

Human Ia-like alloantigens have been solubilized from membranes of B lymphoblastoid cell lines using sodium deoxycholate (DOC). They have been purified by affinity chromatography using specific rabbit antibodies bound to an agarose column, eluting the antigens at pH 11.0 in the presence of 0.5% DOC. The isolated, purified, material contained two proteins of molecular weights 35 000 and 27 000 by sodium dodecyl sulfate gel electrophoresis, apparently noncovalently associated with each other. The molecules were completely separated from the soluble products of the HLA-A, B and C loci and retained serological activity as measured by their capacity to inhibit the lysis of B lymphoblastoid cell lines by B cell-specific alloantisera.