Study of the population dynamics of human diploid cell strain WI-38: III. Serial cultivation of the cells

Abstract

When a 1 : 2 passage system was used the lifespan of WI-38 cells was the same in Basal Medium Eagle (BME) containing glucose and in BME containing galactose and sodium pyruvate; in both cases 33 population doublings were reached before the final ‘Phase III’ occurred. In both cases also the maximum cell yields decreased continuously during serial cultivation. In BME containing glucose the decrease was 0·011 log 10 per generation and using BME containing galactose and sodium pyruvate substituted for glucose it was 0·015 log 10. On the other hand, if a constant and reduced inoculum of 10 4·2 cells/cm 2 was used at each transfer the lifespan of WI-38 cells was about the same (i.e. 34 population doublings) in BME containing galactose and sodium pyruvate substituted for glucose, but in BME containing glucose it was longer by about seven population doublings. The maximum cell yields in the medium with galactose and sodium pyruvate present decreased by 0·062 log 10 and in the medium containing glucose by 0·015 log 10 per population generation.