Role of P-selectin and leukocyte activation in polymorphonuclear cell adhesion to surface adherent activated platelets under physiologic shear conditions (an injury vessel wall model)

摘要: Carbohydrate moieties on leukocytes adhere to activated platelets via P- selectin under static binding condition studies. We characterize polymorphonuclear cell (PMN) surface interactions with adherent and the PMNs response, physiologic flow conditions corresponding a shear of 100 s-1, in an vitro chamber. Fluorescent labeled red blood cells were drawn through transparent channel visually quantitated over 30 minutes, interacting confluent monolayer activated, shear-spread expressing P-selectin. PMN adhesion was saturable (2,250 +/- 350/mm2), time cation (Ca2+, Mg2+) dependent, did not bind experimental absence platelet monolayer. P-selectin antibodies completely abolished concentration-dependent manner half inhibition at 70 micrograms/mL. Antibodies putative receptor CD15 (80H5 MMA) maximally inhibited by 73% 10%, respectively. Adherent appeared morphologically cytometric analysis confirmed activation because CD11b CD18 expression upregulated (100% 27%, respectively), whereas L-selectin downregulated (55%) compared control nonadherent PMNs. In presence metabolic inhibitor sodium azide (0.02% 0.1%) there 23% 9% 51% 3% decrease, respectively, s-1. Thus, is required for pathophysiologic rates. Furthermore, secondary step involving after appears necessary complete (irreversible) occur. This unique provides model explore, controlled conditions, biologic mechanisms ligands involved leukocyte-platelet that play important roles localization sites thrombosis vascular injury.