Effects of Antibiotics on Multiplication of L Cells in Suspension Culture

Abstract

Inhibition of multiplication of L cells in suspension culture was used in a screen for cytotoxic agents. A study of the effects of 38 antibiotics on multiplication of this cell line of mouse fibroblasts showed that the following inhibited cell multiplication at concentrations less than 1 [mu]/ml: actinomycins B, BV and DIV; cycloheximide; gliotoxin; mitomycin C; patulin; theostrepton; and Xanthomycin. Actinomycin By was the most cytotoxic; 1.5 [mu]/ml was sufficient to cause a 50% reduction of multiplication of the L cells. While the shape of the dose-response curves varied with the different inhibitors, it was possible to use the linear position in a quantitative estimation of concentration of inhibitors present. This has been useful in determining the potency of cytotoxic agents formed in microbial fermentations.