OxyFile #238

Hydrogen peroxide as a potent activator of T lymphocyte 
functions.


Author:  Los M; Dröge W; Stricker K; Baeuerle PA; 
         Schulze-Osthoff K

Source:  Eur J Immunol 1995 Jan; 25(1):159-65

Abstract:

During inflammatory processes infiltrating cells produce 
large amounts of reactive oxygen intermediates (ROI). Increasing 
evidence suggests that ROI besides being cytotoxic may 
act as important mediators influencing various cellular 
and immunological processes. In this study, we have investigated 
the effects of hydrogen peroxide on several aspects of 
lymphocyte activation. In ESb-L T lymphoma cells, micromolar 
concentrations of hydrogen peroxide rapidly induced activation 
of the transcription factor NF-kappa B, whereas DNA-binding 
activity of the transcription factor AP-1 was virtually 
not affected. In addition, hydrogen peroxide induced early 
gene expression of interleukin-2 (IL-2) and the IL-2 receptor 
alpha chain. The stimulation of IL-2 expression was found 
to be conferred by a kappa B-like cis-regulatory region 
within the IL-2 gene promoter. In contrast to these activating 
effects, addition of hydrogen peroxide was largely inhibitory 
on cell proliferation which is consistent with a general 
requirement of thiol compounds for lymphocyte proliferation. 
However, hydrogen peroxide significantly increased T cell 
proliferation when applied for a short period under reducing 
conditions. These data indicate that ROI may act as an 
important competence signal in T lymphocytes inducing early 
gene expression as well as cell proliferation.