Oxidant-induced stress response in lymphoid cells.

The stress response to reactive oxygen species is an important defence system which can reduce their potential to induce biomolecule damage. In this investigation the effect of exposing Molt-3 lymphoblastoid cells or peripheral blood lymphocytes to a non-toxic dose of hydrogen peroxide (10 microM) was studied. Cellular response to a subsequent high dose of hydrogen peroxide (100-200 microM) was assessed by measurement of growth, viability, proliferation and DNA damage (lymphocytes only) and intracellular activities of the enzymes, superoxide dismutase, glutathione peroxidase and catalase (Molt-3 only). The results indicate that pretreatment of lymphocytes with 10 microM hydrogen peroxide can elicit a response which is protective against DNA damage normally inducible in these cells by subsequent exposure to toxic doses of hydrogen peroxide. It appears from the results with Molt-3 cells that altered activities of glutathione peroxidase may contribute to this enhanced resistance to hydrogen peroxide.