Phosphorylation of nuclear proteins of peripheral blood T lymphocytes activated by nickel sulfate and mercuric chloride.

The phosphorylation of nuclear proteins of peripheral blood T lymphocytes activated by nickel sulfate or mercuric chloride, and from nickel-allergic subjects, was studied in polyacrylamide gel separations of 32P-labeled proteins. With a preincubation period of the metal salts for 48 h, a marked increase of 32P label into nonhistone proteins, especially the 30- to 40-kilodalton region, was found compared to the control cultures. This increase was most pronounced in mercuric-chloride-treated cultures, which also showed an increase in labeling of histone H4. The increase in nuclear protein phosphorylation probably reflects an activation of the lymphocytes. Moreover, the difference in phosphorylation pattern between mercuric-chloride- and nickel-sulfate-activated lymphocytes might be due to different mechanisms of action for polyclonal and monoclonal activators, respectively.