ACTIVATION OF HUMAN T-HELPER-1 AND DNAASE EXPRESSION IN CD4(-CELLS INDUCED BY SHORT IMMUNOMODULATING PEPTIDES() T)

Activation of human T helper 1 cells took place when lymphomononuclear cells from healthy donors were incubated in the presence of short syn thetic peptides encompassing sequences present in extracellular matrix proteins. Active peptides conformed to a common structural pattern (' '2-6-11 motif'') [N.Lopez-Moratalla et al., Biochem. Biophys. Acta (19 94) 1221, 153-158] conferring immnunomodulating properties. The releas e of IL-2 and IFN gamma, as well as LAK and NK-dependent cytotoxicity induced by these peptides, could be blocked by anti-HLA-DR antibody. A ctivated CD4(+) cells isolated from the mixed incubated population con tained secretion granules with DNAase activity. These results suggest that these immunomodulating peptides presented by HLA-II play a key ro le in the differentiation of CD4(+) T cells towards a Th1 functional p henotype. (C) 1994 Academic Press, Inc.