Effects of culturing technique on human peripheral blood lymphocytes response to proton and X-ray radiation.

The main aim of this study was to comparatively investigate the effects of culturing methods on the response of human peripheral blood lymphocytes to irradiation exposure. Whole blood and isolated lymphocytes were ex vivo exposed to two radiation sources (60 MeV proton or 250 kV X-ray radiation) with different doses (0.3, 0.5, 0.75, 1.0, 1.5, 2.0, 2.5, 3.0, and 4.0 Gy), and genotoxic markers were subsequently assayed. The observed effects were compared as dose-response relationships using two end points (CBMN and PCC tests) and different biomarkers (NDI, PCC index, MNi frequency and excess PCC fragments). The results showed different effects of the culturing techniques on the response of human peripheral blood lymphocytes to radiation. The MNi frequency and excess PCC fragments were significantly higher when lymphocytes were cultured after being isolated. After irradiation, no differences were seen in the NDI between the lymphocytes of the two culturing techniques; however, there were differences in the PPC index. When planning or performing cytogenetic studies, the possibility of such effects and their potential to impact the variability of the results of human biomonitoring studies should be considered important and taken into account.