An erythrocyte glycoprotein of apparent Mr 60,000 expresses the Sc1 and Sc2 antigens.

Immunoblotting with human anti-Sc1 and anti-Sc2 locates the Sc1 and Sc2 antigens to an erythrocyte membrane glycoprotein of apparent Mr 60,000. The antigens are destroyed by pronase, and require intact disulphide bonds for expression. A proportion of the molecules carrying the Sc1 and Sc2 antigens are associated with red cell cytoskeleton preparations. Treatment of intact cells with an Endo F preparation resulted in the loss of the Sc2 antigen but not the Sc1 antigen, suggesting that the Sc2 antigen is dependent on the presence of one or more complex N-glycans for its expression.