HUMAN HELPER AND MEMORY LYMPHOCYTES EXHIBIT AN INDUCIBLE ELASTIN-LAMININ RECEPTOR

We showed recently that human activated lymphocytes express the elasti n-laminin receptor. In this study, we were interested in the kinetics of the induction of this receptor on human activated lymphocytes in vi tro and in the quantification of its expression on different human lym phocyte subsets. It appears that the expression of the elastin-laminin receptor is a general property of most activated human lymphocytes bu t strongly dependent on the lymphocyte subsets. It appeared that the h elper (CD4+) and memory (CD45RO+) lymphocytes exhibited the strongest increase of elastin-laminin receptor expression when cultured for 72 h in the presence of 2 mu g/ml elastin peptides (2.7 x 10(-8) M) as com pared to control cells. Activation of this receptor by elastin peptide s triggers the stimulation of biosynthesis and release of a PMN-like e lastase. Activated T lymphocytes (mostly helper and memory T cells) ar e present from early stages of the atherosclerotic process and this re lease could contribute to the progression of the lesion by engaging a vicious circle with more elastin peptides released attracting more mon onuclear cells and increasing their elastase production.