Induction of the bystander effect in human somatic cells by X-ray irradiation in vitro at low and high doses

The results of the cytogenetic investigation of the radioinduced bystander effect with the help of a mixed culture of irradiated by X-rays and unirradiated human blood lymphocytes are presented. It is shown that the level of chromosome aberrations in unexposed human lymphocytes cultivated with lymphocytes irradiated in vitro in doses of 0.25 and 1.0 Gy is significantly higher than the frequency of aberrations in control mixed cultures of unirradiated lymphocytes. The frequency of chromosome aberrations in the bystander cells elevated with increasing doses of neighboring populations of lymphocytes due to the increased induction of chromatid breaks.