Levinovitz A, Mühlhoff J, Isenmann S, Vestweber D
Hans Spemann Laboratory, Max-Planck-Institute of Immunology, Freiburg, FRG.
J Cell Biol. 1993 Apr;121(2):449-59. doi: 10.1083/jcb.121.2.449.
E-selectin is an inducible endothelial cell adhesion molecule for neutrophils which functions as a Ca(2+)-dependent lectin. Using a recombinant, antibody-like form of mouse E-selectin, we have searched for glycoprotein ligands on mouse neutrophils and the neutrophil progenitor cell line 32D cl 3. We have identified a 150-kD glycoprotein as the only protein which could be affinity-isolated with soluble E-selectin from [35S]methionine/[35S]cysteine-labeled 32D cl 3 cells. Binding of this protein was strictly Ca(2+)-dependent, was blocked by a cell adhesion-blocking mAb against mouse E-selectin, and required the presence of sialic acid on the 150-kD ligand. This glycoprotein was also affinity-isolated from mature neutrophils, in addition to a minor component at 250 kD, but could not be isolated from several other non-myeloid cell lines. The 150-kD glycoprotein was the only protein from 32D cl 3 cells, which was detectable by silver-staining after a one-step affinity-isolation.
E选择素是一种可诱导的、对中性粒细胞起作用的内皮细胞粘附分子，其功能为一种依赖钙离子的凝集素。利用重组的、抗体样形式的小鼠E选择素，我们在小鼠中性粒细胞和中性粒细胞祖细胞系32D cl 3上寻找糖蛋白配体。我们已鉴定出一种150-kD糖蛋白，它是唯一一种能与可溶性E选择素从[35S]甲硫氨酸/[35S]半胱氨酸标记的32D cl 3细胞中进行亲和分离的蛋白质。该蛋白的结合严格依赖钙离子，被抗小鼠E选择素的细胞粘附阻断单克隆抗体所阻断，并且在150-kD配体上需要唾液酸的存在。除了250 kD的次要成分外，这种糖蛋白也能从成熟中性粒细胞中进行亲和分离，但不能从其他几种非髓系细胞系中分离出来。150-kD糖蛋白是32D cl 3细胞中唯一一种在一步亲和分离后能用银染检测到的蛋白质。
