ABSTRACT
OBJECTIVE: To explore the effect of~(56)Fe~(17+)heavy ion on the expression of phosphorylated histone H2AX( γH2AX) of human lymphccytes. METHODS: The Epstein-Barr virus transformed human B lymphocyte cell lines( PengEBV) were selected and exposed to~(56)Fe~(17+)heavy ion at irradiation dose of 0. 0( control group),0. 1,0. 3,0. 5,0. 7,1. 0 and 2. 0 Gy,respectively,with the dosing rate of 0. 23-0. 55 Gy / min. Flow-cytometry was used to detect the changes of expression of γH2AX at time points of 0,2,4,8,48 and 72 hours after irradiation. RESULTS: The expression of γH2AX showed interaction existed between radiation dose and the treatment time after radiation( P < 0. 01). Compared with the control at the same time points,the expression of γH2AX increased at the dose of 0. 3-2. 0 Gy and the time points of 2-72hours( P < 0. 05). The expression of γH2AX at the dose of 0. 3-2. 0 Gy and time points of 8-72 hours was lower than those at the same dose and time points of 2 and 4 hours( P < 0. 05). When the dose was at 0. 5,1. 0 or 2. 0 Gy,the expression of γH2AX decreased with the increasing time of exposure in 72 hours( P < 0. 05). At the dose of 0. 0-1. 0 Gy and the time points of 2-4 hours,the expression of γH2AX increased with the increasing dose of irradiation( P < 0. 01). CONCLUSION: The expression of γH2AX in Peng-EBV cells shows a dose-response relationship within 2-4 hours after 0. 0-1. 0 Gy irradiation of~(56)Fe~(17+).