Correction of genetic instability of the genome by fractional irradiation of MDBK cells

Abstract

With respect to given contradictory data in radiobiology, that according to some authors, irradiation of cells of plant and animal origin initiates DNA changes and according to others, repeated irradiation of cells in small doses has a stimulating effect on metabolism without increasing the purity of mutations, we conducted the present study, with the aim to study the stability of the genome of MDBK cell line against a background of single and double (fractional) irradiation. The object of the study was a continuous MDBK cell line (Madin-Darby Bovire Kidney Cell, cattle, kidney), which was grown in medium 199, manufactured by Federal State Budget Institution FCTRB-ARRVI (Kazan) with 10% bovine serum and the addition of antibiotics (benzylpenicillin sodium salt, kanamycin at 100 units/ml) (streptomycin sulfate at 100 μg/ml) according to standard procedure. A monolayer culture of MDBK cells in the logarithmic growth phase (3-4 days after culture) served as contacting cells. As a result, a radio-modified cell line, called MDBK-2, was obtained. Moreover, in an unirradiated MDBK cell culture, the level of chromosomal breakdowns was in the range of 1.03-3.1% with respect to the total number of studied anaphases. Based on the obtained data, it can be concluded, that during prolonged cultivation of MDBK cells, irradiated in a small (adaptive) dose and re-irradiated in 3-minute higher dose (5.95 Gy), there is a significant decrease in the yield of aberrant cells, induced by a test dose of γ-rays.