Wallick S C, Kabat E A, Morrison S L
Department of Microbiology, Columbia University College of Physicians and Surgeons, New York, New York 10032.
J Exp Med. 1988 Sep 1;168(3):1099-109. doi: 10.1084/jem.168.3.1099.
We have observed that antidextran hybridomas with potential N-linked glycosylation sites in VH have higher affinity for polymeric dextran and for isomaltoheptaose than those lacking potential glycosylation sites. In these studies we have used gene transfection and expression techniques to verify that the carbohydrate addition sites in VH were used. The carbohydrate of the VH region was accessible for binding by the lectin Con A. By ELISA analysis it was demonstrated that the aKa of the antibody for dextran was influenced by the presence of carbohydrate in VH, with the aglycosylated antibody having an aKa 15-fold lower than its untreated counterpart. The aKa for antigen of antibodies that contain carbohydrate only in their constant region was unaffected by lack of carbohydrate. Thus, not only the amino acid sequence of the variable region but also its carbohydrate moieties can determine the magnitude of the antigen-antibody interaction.
我们观察到，VH中具有潜在N-连接糖基化位点的抗右旋糖酐杂交瘤对聚合右旋糖酐和异麦芽七糖的亲和力高于那些缺乏潜在糖基化位点的杂交瘤。在这些研究中，我们使用基因转染和表达技术来验证VH中的碳水化合物添加位点是否被利用。VH区域的碳水化合物可被凝集素Con A结合。通过ELISA分析表明，抗体对右旋糖酐的亲和力常数（Ka）受VH中碳水化合物的影响，无糖基化抗体的Ka比未处理的对应抗体低15倍。仅在恒定区含有碳水化合物的抗体对抗原的Ka不受碳水化合物缺乏的影响。因此，不仅可变区的氨基酸序列，而且其碳水化合物部分都可以决定抗原-抗体相互作用的强度。
