[The effect of Mycoplasma contamination and decontamination with ciprofloxacin on the karyotypic structure of the Chinese hamster V-79 lung cell line].

Karyotypic variability was investigated for the Chinese hamster lung cell line V-79, infected (contaminated) with a mycoplasma Acholeplasma laidlawii A. The mycoplasmal contamination did not affect cell distribution for the chromosome number. However, 30-70 days following cell culture contamination the increase in chromosomal aberrations was observed in the contaminated cell line primarily at the expense of chromosomal breaks. The following cyprofloxacin treatment of the culture resulted in mycoplasmal elimination and decrease in the frequency of chromosomal aberrations up to the control level. The analysis of G-banded chromosomes showed no significant differences in karyotypes of originally non-infected cells and cells after decontamination. The karyotypic variability, induced by mycoplasmal infection in V-79 cell line, differed from that in the muntjac skin fibroblast cell line, the latter being described elsewhere. A predominant type of chromosomal variability in V-79 cell line are chromosomal breaks, whereas in the muntjac fibroblast cell line dicentrics (telomeric fusions) were primarily observed, possible explanations of these differences being discussed. This may be presumably due to differences in karyotypic structure of these two cell lines, and to their different adaptation to culture conditions.