Patanjali S R, Sajjan S U, Surolia A
UGC Centre for Advanced Studies, Indian Institute of Science, Bangalore.
Biochem J. 1988 Jun 15;252(3):625-31. doi: 10.1042/bj2520625.
An acidic lectin (WBA II) was isolated to homogeneity from the crude seed extract of the winged bean (Psophocarpus tetragonolobus) by affinity chromatography on lactosylaminoethyl-Bio-Gel. Binding of WBA II to human erythrocytes of type-A, -B and -O blood groups showed the presence of 10(5) receptors/cell, with high association constants (10(6)-10(8) M-1). Competitive binding studies with blood-group-specific lectins reveal that WBA II binds to H- and T-antigenic determinants on human erythrocytes. Affinity-chromatographic studies using A-, B-, H- and T-antigenic determinants coupled to an insoluble matrix confirm the specificity of WBA II towards H- and T-antigenic determinants. Inhibition of the binding of WBA II by various sugars show that N-acetylgalactosamine and T-antigenic disaccharide (Thomsen-Friedenreich antigen, Gal beta 1-3GalNAc) are the most potent mono- and di-saccharide inhibitors respectively. In addition, inhibition of the binding of WBA II to erythrocytes by dog intestine H-fucolipid prove that the lectin binds to H-antigenic determinant.
通过乳糖基氨乙基-生物凝胶亲和层析，从四棱豆（Psophocarpus tetragonolobus）种子粗提物中分离出一种酸性凝集素（WBA II）并达到均一。WBA II与A、B、O血型人红细胞的结合显示每个细胞存在10⁵个受体，具有高缔合常数（10⁶ - 10⁸ M⁻¹）。用血型特异性凝集素进行的竞争性结合研究表明，WBA II与人红细胞上的H和T抗原决定簇结合。使用与不溶性基质偶联的A、B、H和T抗原决定簇进行的亲和层析研究证实了WBA II对H和T抗原决定簇的特异性。各种糖类对WBA II结合的抑制表明，N-乙酰半乳糖胺和T抗原二糖（汤姆森-弗里德赖希抗原，Galβ1-3GalNAc）分别是最有效的单糖和二糖抑制剂。此外，犬肠H-岩藻糖脂对WBA II与红细胞结合的抑制证明该凝集素与H抗原决定簇结合。
