RESUMO
We investigated the effect of plasma ceruloplasmin (Cp) on the different types of lymphocyte rosetting, and phagocytosis of polystyrene particles and culture Candida albicans by peripheral blood neutrophils and monocytes. Lymphocytes, neutrophils, and monocytes were isolated from the blood of patients with elevated immuno-status (n = 9), healthy donors (n = 21), and patients with reduced immuno-status (n = 21). The ability of Cp to decrease the number of lymphocytes forming E- and EAC-rosettes and rosettes with auto-erythrocytes was shown for both patients and healthy donors. The maximal decrease of the number of E-rosettes (by 35%) and EAC-rosettes (by 57%) was shown for lymphocytes of the patients with elevated immuno-status. Cp had an effect on rosetting only when lymphocytes were preincubated with it, suggesting that Cp binding to lymphocytes was responsible for these effects. The decrease in all types of rosetting caused by Cp was dose-related, with a maximum effect at physiological concentration of Cp (300 micrograms/ml). We demonstrated an enhancing effect of Cp on phagocytosis of Candida albicans and polystyrene particles by neutrophils (with a maximum enhancement by 180% for neutrophils of the patients with decreased immuno-status) and monocytes (with a maximum of 89% for monocytes of healthy donors). Cp enhances phagocytosis of neutrophils and monocytes by binding these cells, not by opsonizing ingested particles as a conventional opsonin (ie. lipopolysaccharide from E.coli). The stimulating effect of Cp on phagocytosis was three times higher than that of LPS from E.coli.
