Use of a monoclonal antibody (W6/32) in structural studies of HLA-A,B,C, antigens.

The isolated HLA-A chain from intact 125I-HLA-A2 antigens weakly bound to W6/32 antibody in contrast to 125I-β2-microglobulin (β2m) isolated from the same preparation of HLA-A2 antigens that showed no demonstrable binding. when an excess of cold β2m was added to the isolated 125I-HLA-A2 chain, the binding to W6/32 antibody was considerably enhanced. These results suggest that the W6/32 antigenic determinant involves only amino acids of the HLA-A,B,C chain and is a product of their three dimensional configuration. Stable maintenance of this configuration appears to be dependent on the association of the HLA-A,B,C chain with β2m.