Department of Pathology, College of Physicians and Surgeons, Columbia University, New York.
J Gen Physiol. 1937 Mar 20;20(4):603-19. doi: 10.1085/jgp.20.4.603.
Adult tissue is characterized by a lag period of several days preceding the onset of growth in vitro. Treatment of fresh adult tissues with trypsin before planting them in culture flasks stimulated the tissues to grow sooner and more rapidly. Best stimulation was obtained by slow digestion at low temperature. The tissues lost nitrogen during the digestion. Lowering the temperature from 22 degrees C. to 5 degrees C. reduced the digestion of aorta tissue much less than it reduced the digestion of casein. Washing the tissue after trypsin treatment resulted in better stimulation. Trypsin solutions of different degrees of purity, when diluted to equal activity toward casein, gave equal stimulation to the tissue growth. These included solutions of Northrop's crystalline trypsin and chymo-trypsin. Papain also stimulated growth in a similar manner. The results indicate that this stimulation of tissue growth is due entirely to proteolytic action. Cultures of adult fibroblasts (and some tumor cultures) having reached a state of retarded growth have been treated with trypsin to digest away most of the plasma clot (used as a medium). Fresh plasma has been added to renew the clot. This treatment has resulted in an immediate renewal of growth. Reasons are given for supposing that the cells produce an inhibitor in vitro which they deposit in the surrounding clot, and which is removed by the action of trypsin.
成体组织的特点是在体外生长开始之前有几天的潜伏期。在将新鲜的成体组织种植到培养瓶中之前，用胰蛋白酶处理可以刺激组织更快地生长。最佳的刺激效果是在低温下缓慢消化。组织在消化过程中会损失氮。将温度从 22°C 降低到 5°C 会使主动脉组织的消化减少，但比使酪蛋白的消化减少得少。胰蛋白酶处理后清洗组织可获得更好的刺激效果。当稀释到对酪蛋白具有同等活性时，不同纯度的胰蛋白酶溶液对组织生长的刺激作用相同，其中包括 Northrop 结晶胰蛋白酶和 chymo-trypsin 溶液。木瓜蛋白酶也以类似的方式刺激生长。结果表明，这种组织生长的刺激完全是由于蛋白水解作用。已经用胰蛋白酶处理达到生长迟缓状态的成体成纤维细胞（和一些肿瘤培养物）的培养物，以消化掉大部分用作培养基的血浆凝块。已经添加新鲜血浆以更新凝块。这一处理立即导致了生长的恢复。有理由假设细胞在体外产生一种抑制剂，它沉积在周围的凝块中，并被胰蛋白酶的作用所去除。
