Steady-State Effects of Vitronectin and Fibronectin on the Binding, Uptake, and Degradation of Pneumocystis Carinii by Rat Alveolar Macrophages

摘要: Pneumocystis carinii pneumonia remains a serious complication of immunodeficiency. Vitronectin (VN) and fibronectin (FN) accumulate in the lung during P. infection bind to organism, thereby enhancing macrophage release TNFα. It is not known whether VN FN also regulate uptake degradation by macrophages when present concentrations similar those pneumonia. To address this, were cultured with 35S-radiolabeled organism binding, phagocytosis, determined media alone (control), or presence (100 μg/ml each). Soluble FN, host, did significantly affect alveolar macrophages. Thus, although enhance activation pneumonia, phagocytosis increased these host glycoproteins under steady-state conditions.