A safe and efficient method for elimination of cell culture mycoplasmas using ciprofloxacin.

The antibacterial activity of ciprofloxacin, a 4-fluoroquinolone antibiotic, in the control of mycoplasma contamination in experimentally infected cell lines has been investigated. Seven mycoplasma species, including M. hyorhinis, M. gallisepticum, M. orale, M. salivarium, M. hominis, M. fermentans, and M. arginini, which had chronically infected the murine plasmocytoma line X63-Ag8 653, were eradicated with 10 micrograms/ml ciprofloxacin. Wild type laboratory infections of two human cell lines, HL-60 and U-937, were eliminated by 12 days of such treatment. Mycoplasma decontamination of cell cultures was monitored by the cultivation method 4 weeks after treatment. No side effects were seen in cell cultures and complex proliferation assays with cells of human and murine origin, using ciprofloxacin in doses up to 2.5 times the usual bactericidal concentration.