Wu J H, Watkins W M, Chen C P, Song S C, Wu A M
Department of Microbiology and Immunology, Chang-Gung, Medical College, Kwei-san, Tao-yuan, Taiwan.
FEBS Lett. 1996 Apr 22;384(3):231-4. doi: 10.1016/0014-5793(96)00320-1.
Unlike the human blood group Sd(a+) Tamm-Horsfall glycoprotein (THGP), the Sd(a-) one lacks terminal GalNAcbeta1--> residues at the nonreducing ends. The binding properties of this glycoprotein and its asialo product with lectins were characterized by quantitative precipitin (QPA) and precipitin inhibition assays. Among 20 lectins tested by QPA, both native and asialo Sd(a-) THGP reacted best with Abrus precatorius and Ricinus communis and completely precipitated the lectin added. They also precipitated well Wistaria floribunda (WFA), Glycine max (SBA), Bauhinia purpurea alba, abrin-a and ricin, all of which recognize the Galbeta1--> 4GlcNAcbeta1--> sequence, although at different strength. The lectin-glycan interactions were inhibited by Galbeta1--> 4GlcNAc and Galbeta1--> 4Glc. When the precipitability of Sd(a-) THGP was compared with that of the Sd(a+) phenotype, the native Sd(a-) THGP exhibited a 40% lesser affinity for WFA, SBA, WGA and mistletoe lectin-I (ML-I). Mapping the precipitation and inhibition profiles of the present study and the results of THGP Sd(a+), it is concluded that Sd(a-) THGP showed a strongly diminished affinity for GalNAcbeta1--> active lectins (SBA and WFA) than the Sd(a+) phenotype.
与人类血型为Sd(a+)的Tamm-Horsfall糖蛋白（THGP）不同，Sd(a-)的Tamm-Horsfall糖蛋白在非还原端缺乏末端GalNAcbeta1-->残基。通过定量沉淀（QPA）和沉淀抑制试验对该糖蛋白及其去唾液酸产物与凝集素的结合特性进行了表征。在通过QPA测试的20种凝集素中，天然和去唾液酸的Sd(a-) THGP与相思豆和蓖麻的反应最佳，并使添加的凝集素完全沉淀。它们对紫藤（WFA）、大豆（SBA）、白花羊蹄甲、相思子毒素-a和蓖麻毒素也有良好的沉淀效果，所有这些凝集素都能识别Galbeta1--> 4GlcNAcbeta1-->序列，尽管强度不同。凝集素-聚糖相互作用受到Galbeta1--> 4GlcNAc和Galbeta1--> 4Glc的抑制。当将Sd(a-) THGP的沉淀性与Sd(a+)表型的沉淀性进行比较时，天然Sd(a-) THGP对WFA、SBA、WGA和槲寄生凝集素-I（ML-I）的亲和力低40%。根据本研究的沉淀和抑制图谱以及THGP Sd(a+)的结果，可以得出结论，与Sd(a+)表型相比，Sd(a-) THGP对GalNAcbeta1-->活性凝集素（SBA和WFA）的亲和力大大降低。
