Abstract
Protease-activated receptors (PARs) are a subfamily of four G-protein-coupled receptors mediating multiple functions. PARs expression was studied in subpopulations of human lymphocytes. Our results indicate that natural killer cells expressed mRNA for PAR&sub1;, PAR&sub2; and PAR&sub3;, CD4+ T cells expressed PAR&sub1; and PAR&sub2;, while γδ and CD8+ T cells only expressed PAR&sub1;. PAR&sub4; was absent at mRNA level and B cells did not express any PAR. Analyses of the cell surface PARs expression by flow cytometry were consistent with the mRNA data and also between different donors. PAR&sub1; is the most abundant member of the PAR family present in lymphocytes.