[Primary culture of endothelial cells from the human umbilical vein: identification and characteristics of a growing and confluent culture].

Endothelial cells (EC) were derived selectively from the intimal surface of human umbilical veins with a 0.1% collagenase solution, after Gimbrone et al. (1974) with some modifications. The plating efficiency to plastic was 70-75% for 24 hours in collagenase dispersed cells. A confluent monolayer with cell density 10(5) cells/cm2 as formed by 5-8 days. The optimal cell growth was obtained with seed density 5-8 X 10(4) cells/cm2. The EC were identified in culture using the following hallmarks: a) the presence of the Weibel-Palade bodies in the cytoplasm, b) VIII coagulation factor, c) silver staining of EC borders in monolayer. The EC doubling time in the log phase of growth was shown to be 48-56 hours. The contact DNA inhibition was demonstrated in confluent culture with 3H-thymidine incorporation and by means of a cell flow-cytofluorometry method. The same methods were used for evaluating the homogeneity of EC in culture.