Enzyme-linked immunoabsorbent assay studies of antibody binding to recombinant glycoprotein (GP)Ib.

(A) Binding of anti-human platelet antigen (HPA)-2a and -2b to Thr-145 and Met-145 forms. (B) Binding of three examples of anti-HPA-2b and a negative control serum to glycosylated and nonglycosylated (NG) Met-145.