Assessment of γH2AX nuclear foci number and size in normal and repair-deficient cells irradiated with low and high linear energy transfer radiation

BRACALENTE C; IBAÑEZ IL; MOLINARI B; PALMIERI M; MAGLIOCO A; POLICASTRO L; KREINER A; BURLON A; VALDA A; DAVIDSON J; DAVIDSON M; DURAN H

International Journal of low radiation

INDERSCIENCE

Año: 2010 p. 393 - 408

1477-6545

The aim of this study was to evaluate the DNA damage induced bylow and high linear energy transfer radiation in two related cell lines withdifferent radiation sensitivity, CHO10B2 and irs-20 cells (defective in DNAPKcs).Double-strand breaks were assessed by the detection of phosphorylatedhistone H2AX foci (γH2AX). The number of foci increased as a function ofdose for both cell lines and types of radiation. However, irs-20 cells showeda higher number of foci than the parental CHO10B2. An increase in the focisize was observed for both cell lines after lithium irradiation. This could beattributed to clusters of DNA damage. Moreover, the number of lithiuminducedlarger foci per nuclei increased with dose and fitted with the expectednumber of hits per nucleus. Concluding, γH2AX foci size provides a potentialtool to characterise the intrinsic radiosensitivity of cells related to DNAdamage and to compare the effects of different quality radiations.