A Simplified Chemostat for the Growth of Mammalian Cells: Characteristics of Cell Growth in Continuous Culture

A simplified technique has been described for the continuous growth of mammalian cells in suspension culture. The cell population density increased as the rate of input of fresh medium was decreased, and the average generation time was concommittantly prolonged. At relatively high input rates, the population remained stabilized for an indefinite period, but at low flow rates, there was sometimes a cyclical variation in population density. The factor limiting growth rate at input rates of approximately 0.2 volumes per day was not the exhaustion of the medium; but in some experiments a non-dialyzable material appeared which inhibited cell growth.