The Bulk Growth of Animal Cells in Continuous Suspension Culture

Abstract

SUMMARY: Several methods for growing animal cells in suspension culture were examined, to find the most efficient in terms of cells produced in a given time for the minimum of medium and attention. Continuous medium flow was more efficient than batch-culture, and the preferred system was to add medium to a culture vessel regularly in small doses via a time-switch-controlled solenoid closure at a rate similar to the growth rate; a turbidimetric safety device ensured that cell density did not drop below levels permitting growth. A mixture of galactose or fructose (6 g./1.) and glucose (2 g./1.) allowed better pH control than glucose alone (6 g./1.). Doubling times of 14r–16 hr. were obtained on occasion; the gas-phase oxygen concentration for fastest growth depended on cell density and was frequently less than atmospheric, suggesting that these cells can behave as microaerophils.702