Selectin P (PADGEM GMP-140)—Mediated Adhesion of Human Platelets to Neutrophils in Vitro and the Immune Complex-induced Peritoneitis in Rats is Influenced by Interleukin-8

The expression of Selectin-P was measured in terms of formation of “rosettes” by human gell-filtrated, thrombin (30-50 mU)—stimulated platelets on the surface of isolated homologous neutrophilic leukocytes (PMNs) according to Jungi (1986). The monoclonal anti-Selectin P-antibody completely prevented formation of “rosettes” proving the specificity of Selectin-P mediation of adhesion. IL-8 (50–200 ng/ml) concentration-dependently inhibited the adhesion of platelets to PMNs. Neither Aspirin nor L-NO2Arg, modified the inhibitory activity of IL-8. The Ova-antyOva-complex-induced peritoneitis in rats was associated with the accumulation of PMNs and protein in abdominal cavity as soon as after 2 hours after i.p. injection of complexes. The pretreatment of rats with IL-8 (1 μg/300g) decreased the number of PMNs migrating to abdominal cavity, and tended to decrease their ability to synthetise NO. The suggested by Gimbrone et al. (1989) anti-inflammatory properties of a circulating form of IL-8 seems to be related ...