Differential binding of human blood group Sd(a+) and Sd(a−) Tamm-Horsfall glycoproteins with Dolichos biflorus and Vicia villosa-B 4 agglutinins

Abstract

The binding patterns of human blood group Sd(a+) and Sd(a−) Tamm-Horsfall glycoproteins (THGPs) with respect to four GalNAc specific agglutinins were studied by quantitative precipitin assay (QPA) and enzyme linked lectinosorbent assay (ELLSA). Of the native and asialo Sd(a+) and Sd(a−) THGP tested by QPA and ELLSA, only native and asialo Sd(a+) bound well with Dolichos biflorus (DBA) and Vicia villosa-B 4 (VVA-B 4), while Sd(a−) THGP reacted poorly with these two lectins. Neither Sd(a+) nor Sd(a−) THGPs reacted with two other GalNAc α-anomer specific lectins: Codium fragile subspecies tomentosoides and Artocarpus integrifolia. Furthermore, the binding of asialo Sd(a+)THGP-VVA-B 4 and native Sd(a+)THGP-DBA through GalNAcβ→ was confirmed by inhibition assay. These results demonstrate that DBA and VVA-B 4 are useful reagents to differentiate between Sd(a+) and Sd(a−) THGP.