Sprengers E D, Princen H M, Kooistra T, van Hinsbergh V W
J Lab Clin Med. 1985 Jun;105(6):751-8.
Primary cultures of human hepatocytes and the human hepatocellular cell line Hep G2 are shown to produce fast-acting inhibitors of tissue-type plasminogen activator (tPA) and urokinase. The tPA inhibitory activities in conditioned medium of these liver cell types are very similar to those present in human endothelial cell conditioned medium. They are stable at pH 2.5, have similar dissociation constants with tPA (1.5 to 5 pmol/L), and are similar in thermostability. Addition of tPA to conditioned medium of Hep G2 and endothelial cells that has been depleted of tPA and urokinase reveals a 100 kilodalton tPA-inhibitor complex. The fast-acting tPA inhibitory activity in human plasma has comparable properties, and may originate from the liver or the vascular endothelium or both. After sodium dodecyl sulfate-polyacrylamide gel electrophoresis of conditioned medium from hepatocytes, Hep G2, and endothelial cells, additional fibrinolytic inhibition at 52 kilodaltons was visualized. This was not found with human plasma.
人肝细胞原代培养物和人肝癌细胞系Hep G2可产生组织型纤溶酶原激活物（tPA）和尿激酶的快速作用抑制剂。这些肝细胞类型的条件培养基中的tPA抑制活性与人类内皮细胞条件培养基中的非常相似。它们在pH 2.5时稳定，与tPA的解离常数相似（1.5至5 pmol/L），热稳定性也相似。向已去除tPA和尿激酶的Hep G2和内皮细胞条件培养基中添加tPA，可形成100千道尔顿的tPA-抑制剂复合物。人血浆中的快速作用tPA抑制活性具有类似特性，可能源自肝脏或血管内皮或两者。对肝细胞、Hep G2和内皮细胞的条件培养基进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳后，在52千道尔顿处可见额外的纤维蛋白溶解抑制作用。人血浆中未发现此现象。
