BACTERIA BLOOD MATERIAL INTERACTIONS .1. INJECTED AND PRESEEDED SLIME-FORMING STAPHYLOCOCCUS-EPIDERMIDIS IN FLOWING BLOOD WITH BIOMATERIALS

Blood-material interactions were studied using in vitro recirculation with human blood, slime-forming Staphylococcus epidermidis, and cardio vascular materials. Staphylococcus epidermidis, under preseeded or inj ected conditions, adhered to nonsmooth materials and elevated plasma l evels of fibrinopeptide A (FpA) and C3a in the presence of all materia ls. Increased white blood cell (WBC) and platelet adhesion and thrombo spondin and platelet factor 4 (PF4) release were noted for respective materials in the presence of injected bacteria. Materials that adhered significant quantities of injected S. epidermidis exhibited low level s of adsorbed proteins. Materials with high levels of preseeded S. epi dermidis showed high levels of adsorbed proteins. Adhesion of preseede d bacteria and blood plasma elevations of C3a and FpA were lowest on s emicrystalline polymer substrates, intermediate on halogenated substra tes, and highest on amorphous substrates. In the presence of injected bacteria, WBCs and platelets adhered at earlier recirculation times to amorphous substrates than to semicrystalline substrates. (C) 1995 Joh n Wiley & Sons, Inc.