Effect of Mupirocin on the Growth and Lifespan of Human Fibroblasts

We have examined the effect of the antibiotic mupirocin on the growth and proliferative lifespan of human fibroblasts. Human embryonic lung fibroblasts were grown in Dulbecco's minimal essential medium, containing 10% fetal bovine serum and various concentrations of mupirocin ranging from 0.5–756 μg/ml. There is little difference in the rate of exponential growth and the final saturation density reached between control cultures and those grown in 0.5 μg, 72 μg, or 76 μg/ml mupirocin. Growth was retarded or inhibited in cultures containing 650–750 μg/ml mupirocin. The proliferative lifespan of adult skin fibroblasts was examined in cultures serially subcultivated in medium containing either 7 μg/ml or 100 μg/mi mupirocin. Cultures incubated in these concentrations of mupirocin were capable of reaching their full proliferative potential. This study shows that the growth and proliferative lifespan of human fibroblasts is unaltered in the presence of at least 100 μg/ml mupirocin although growth of human fibroblasts is inhibited by 700 μg/ml mupirocin. These observations suggest that long-term use of low but bactericidal concentrations of mupirocin will not impair growth of fibroblasts in healing wounds.