Chinese hamster ovary cell adhesion to human platelet thrombospondin is dependent on cell surface heparan sulfate proteoglycan.
Chinese hamster ovary cell adhesion to human platelet thrombospondin is dependent on cell surface heparan sulfate proteoglycan.
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中国仓鼠卵巢细胞对人血小板血小板反应蛋白的粘附依赖于细胞表面硫酸乙酰肝素蛋白多糖。
DOI：
10.1172/jci113986
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Mosher,DF
中科院分区：
文献类型：
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作者：
Kaesberg,PR;Ershler,WB;Esko,JD;Mosher,DF
血小板反应蛋白是一种420-kD的血小板α颗粒糖蛋白，与肝素特异性结合。我们检测了CHO K1细胞和三种不同糖胺聚糖（GAG）合成缺陷的突变CHO细胞系对血栓反应蛋白的粘附性。在一项实验中，亲本系（K1）对吸附在组织培养塑料上的血栓反应蛋白有78%的粘附性，CHO S745细胞，正常GAG合成低于6%，有11%的粘附性。CHO S677细胞中，硫酸肝素蛋白聚糖减少，硫酸软骨素蛋白聚糖增加，粘附率为42%。CHO S803细胞中，硫酸肝素蛋白聚糖减少，硫酸软骨素蛋白聚糖正常，粘附率为31%。肝素以浓度依赖性的方式抑制K1细胞对血栓反应蛋白的粘附，但不抑制纤维连接蛋白。硫酸皮炎也有抑制作用，硫酸软骨素没有。K1细胞对缺乏肝素结合nh2末端结构域的血栓反应蛋白核心片段的粘附明显降低。纯化的肝素结合结构域，虽然当被吸附到底物时粘附性差，但抑制了细胞对完整血栓反应蛋白的粘附。当pH值为4.0时，血小板反应蛋白的粘附性比pH值为7.4时更好，包括三种人类肿瘤细胞系。当血小板反应蛋白在pH 7.4下吸附时，与0.1 mM钙或EDTA相比，当血小板反应蛋白在大于或等于0.6 mM钙的存在下吸附时，细胞粘附性更好。这些发现表明，血栓反应蛋白可以吸附到塑料不同程度的暴露于细胞粘附结构域。我们得出结论，CHO细胞上的血栓反应蛋白粘附受体是一种硫酸肝素蛋白多糖，细胞对血栓反应蛋白的粘附取决于吸附的血栓反应蛋白的构象。图片
Thrombospondin is a 420-kD platelet alpha-granule glycoprotein that binds specifically to heparin. We examined adhesion to thrombospondin of CHO K1 cells and three mutant CHO lines with varying deficiencies in glycosaminoglycan (GAG) synthesis. In an experiment in which the parent line (K1) had 78% adherence to thrombospondin adsorbed to tissue culture plastic, CHO S745 cells, with less than 6% normal GAG synthesis had 11% adherence. CHO S677 cells, with decreased heparan sulfate proteoglycan but increased chondroitin sulfate proteoglycan, had 42% adherence. CHO S803 cells, with decreased heparan sulfate proteoglycan and normal chondroitin sulfate proteoglycan, had 31% adherence. Heparin inhibited K1 cell adhesion to thrombospondin, but not fibronectin, in a concentration-dependent manner. Dermatan sulfate but not chondroitin sulfate was also inhibitory. There was markedly decreased K1 cell adhesion to a thrombospondin core fragment that lacked the heparin binding NH2-terminal domain. Purified heparin binding domain, although poorly adhesive when adsorbed to substratum, inhibited cell adhesion to intact thrombospondin. Adhesion was better for all cell lines tested, including three human tumor cell lines, when thrombospondin was adsorbed at pH 4.0 compared with pH 7.4. When adsorption of thrombospondin was done at pH 7.4, cell adhesion was better when thrombospondin was adsorbed in the presence of greater than or equal to 0.6 mM calcium, compared to 0.1 mM calcium or EDTA. These findings suggest that thrombospondin can adsorb to plastic with varying degrees of exposure of a cell adhesion domain. We conclude that the thrombospondin cell adhesion receptor on CHO cells is a heparan sulfate proteoglycan, and that cell adhesion to thrombospondin depends on conformation of adsorbed thrombospondin.Images