Massive Fluid-Suspension Cultures of Certain Mammalian Tissue Cells. II. Glucose Utilization and Cell Proliferation23

Abstract

Utilization of glucose by several established strains of mammalian cells in large, agitated, fluid-suspension cultures under conditions of continuous aeration and agitation has been studied, particularly during the logarithmic phase of growth. The rate of glucose utilization per million nuclei per day ranged from a maximum of 1.51 mg. to a minimum of 0.13 mg. Average rates of glucose utilization by cultures of established cell strains were: 0.86 mg. by human skin epithelial NCTC strain 1769, 0.56 mg. by mouse liver NCTC clone 1469, and 0.38 mg. by mouse fibroblast NCTC clone 929 (strain L). Comparable rates of use during slow growth were 0.71 mg. by 1 culture of high sarcoma-producing NCTC strain 1742, and 0.26 mg. by 1 culture of low sarcoma-producing NCTC strain 2049. The glucose utilization rate appeared to be a fairly constant characteristic of established cell strains when other conditions were uniform. Glucose was generally used at a higher rate during the initial lag phase than during the logarithmic phase; the rate was higher during the early stages of the logarithmic phase than during the later stages of that phase. These trends and the frequently observed simultaneous trend toward lower pH suggest that considerable utilization of lactic or keto acids occurs in the later stages of the logarithmic phase. In cultures of clone 929 cells receiving fresh fluid in thrice-weekly increments without removal of old fluid, a rapid decrease of glucose to exhaustion, in the medium, immediately preceded a sharp population decrease.