Inhibition of DRw antisera reactivity by mono and oligosaccharides

Mono and oligosaccharides were used to inhibit the cytotoxicity of antisera detecting HLA-DRw antigens on monocytes isolated from peripheral blood. Certain sugars preferentially inhibited antisera detecting some DRw antigens and not others. Sera detecting HLA-A and B antigens were not inhibited with the sugars used. Anti-DRw sera blocked the attachment of radiolabeled sugars to monocytes with the same patterns as the reciprocal blocking of cytotoxicity by the sugars. The results were not consistent with the intrepretation that carbohydrates are an antigenic "component" of DRw specificity, but rather that the surface structures, possibly those bearing the DRw antigens, are receptors for mono and oligo saccharides.