Binding sites for elastase on cultured human fibroblasts that do not mediate internalization.
Binding sites for elastase on cultured human fibroblasts that do not mediate internalization.
复制标题
培养的人成纤维细胞上弹性蛋白酶的结合位点，不介导内化。
DOI：
10.1002/jcp.1041300120
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发表时间：
1987
影响因子：
5.6
通讯作者：
Cunningham,DD
中科院分区：
文献类型：
--
作者：
Campbell,CH;Cunningham,DD
弹性蛋白酶的蛋白水解作用与细胞外基质损伤有关，细胞外基质损伤是包括肺气肿和类风湿性关节炎在内的多种病理状况的特征。为了阐明弹性蛋白酶与结缔组织细胞相互作用所涉及的分子事件，本研究旨在研究4°C下弹性蛋白酶与人成纤维细胞的结合。弹性蛋白酶与这些细胞表面的结合位点饱和结合。通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析细胞结合弹性蛋白酶，发现存在一种高分子量复合物（Mr 54，000），该复合物不是与弹性蛋白酶形成的，其催化位点丝氨酸用磷酸二异丙酯基团衍生化。复合物不代表弹性蛋白酶结合蛋白酶连接蛋白或污染血清。与弹性蛋白酶形成复合物的细胞组分在细胞培养基中不能检测到。出乎意料的是，在4°C下预结合的弹性蛋白酶在细胞升温至37°C后未内化。因此，本报告中描述的弹性蛋白酶结合位点不同于参与受体介导的内吞作用和细胞内降解的高亲和力结合位点。
The proteolytic actions of elastases have been implicated in extracellular matrix damage, which is characteristic of a variety of pathological conditions including emphysema and rheumatoid arthritis. In order to elucidate the molecular events involved in elastase interaction with connective tissue cells, the present study was designed to investigate the association of elastase with human fibroblasts at 4°C. Elastase bound saturably to binding sites that were present on the surface of these cells. Analysis of cell‐bound elastase by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis revealed the presence of a high molecular weight complex (Mr54,000) that was not formed with elastase whose catalytic site serine was derivatized with a diisopropylphosphate group. The complex did not represent elastase bound to either protease nexin or contaminating serum. The cellular component with which elastase formed a complex could not be detected in the cell culture medium. Unexpectedly, elastase that had been pre‐bound at 4°C was not internalized after cells were warmed to 37°C. The elastase binding site described in this report is therefore distinct from high affinity binding sites involved in receptor‐mediated endocytosis and intracellular degradation.