Differential DNA damage induced by H 2O 2 and bleomycin in subpopulations of human white blood cells

• Published in: Mutation research. Genetic toxicology and environmental mutagenesis Vol. 652; no. 1; pp. 46 - 53
• Main Authors: Weng, Huachun, Lu, Yuquan, Weng, Zuquan, Morimoto, Kanehisa
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2008
• Subjects: Bleomycin; H 2O 2; Leukocyte subpopulations; SCGE; H 2O 2; Bleomycin; Leukocyte subpopulations; SCGE
• ISSN: 1383-5718; 1879-3592
• DOI: 10.1016/j.mrgentox.2007.12.005

The purpose of this study was to characterize the differential sensitivities of various subpopulations of human white blood cells after exposure to H 2O 2 (an oxidant agent) and bleomycin (a radiomimetic glycopeptide), in vitro, using single-cell gel electrophoresis (SCGE). Human peripheral blood was fractionated into mononuclear cells, which were further separated into monocytes, CD4+ T-cells, CD8+ T-cells, B-cells and natural killer cells (NK cells). The separated fractions were exposed to different doses of H 2O 2 and bleomycin, and then used to measure levels of induced and basal DNA damage. There was a significant increase in the amount of DNA damage in CD4+ T-cells, CD8+ T-cells, NK cells and B-cells when treated with H 2O 2 and bleomycin, whereas monocytes had the lowest sensitivity to H 2O 2 compared with the other cell fractions, but no lower sensitivity to bleomycin. Furthermore, CD4+ T-cells and CD8+ T-cells had the highest levels of basal DNA damage. When basal DNA damage was taken into account, NK cells tended to show a higher sensitivity to H 2O 2 than CD4+ T-cells, CD8+ T-cells and monocytes. In addition, B-cells, which showed lower sensitivity to H 2O 2 than CD4+ T-cells, CD8+ T-cells and NK cells when exposed to lower doses of H 2O 2 (<10 μM), showed higher sensitivity to H 2O 2 at higher doses (>20 μM). On the other hand, B-cells showed the highest sensitivity to bleomycin.