An important method to comment on DNA damage and DNA repair ability:Comet assay

Objective To introduce comet assay and to analyze the DNA damage and repair ability of human fetal lung diploid fibroblasts (2BS) as well as lymphocytes. Methods The mixture of 2BS cells (or lymphocytes) and 1% LMA is put on the gel of 0. 5% NMA. After breakage, electrophoresis and stain, the comet tail distance and comet tail area of 100 cells (per sample) are analyzed with Leica image analysis system. Results There are no obvious comet tail for most of young and senescent 2BS cells as well as lymphocytes from young and senescent donors. The comet tails of 28PD 2BS cells treated with H2O2 are obvious. Moreover, the comet tail distances and tail areas of the cells increase as the concentration of H2O2 increasing. The stastics data of the 28PD 2BS cells exposed to H2O2 are as following. Comet tail distance: s = 1.7 ~3. 5 (μm)、CV = 1. 6% ~ 2. 8% . Comet tail area: s = 1. 5% ~ 2. 3%、CV = 1. 8% ~ 2. 5% . Conclusions The DNA breakage level is low both for young and senescent cell. H2O2 can damage DNA obviously. Comet assay is one of important methods used to comment on DNA damage and DNA repair ability.