Inhibition of CREB transcriptional activity in human T lymphocytes by oxidative stress.

Hydrogen peroxide (HP) induced the phosphorylation of cAMP response element binding protein (CREB) on Ser133 in Jurkat T lymphocytes via p38 and MSK1. Although CREB Ser133 was phosphorylated, increases in HP-stimulated CREB-mediated transcription were absent. T lymphocyte stimulation with anti-CD3 and anti-CD28 induced CREB Ser133 phosphorylation, as well as CREB-mediated transcriptional activity. When CD3/CD28-stimulated lymphocytes were treated with HP, Ser133 was phosphorylated, but TCR-induced CREB-mediated transcriptional activity was reduced. These data provide insight into a potential mechanism by which oxidative stress can alter T cell receptor-induced CREB activation and responsiveness.