Macrophage function in chronic experimental alcoholism. I. Modulation of surface receptors and phagocytosis

In the present study, we have assessed peritoneal, alveolar and splenic macrophages for expression of Fc and C3b surface receptors and their ability to function in immunophagocytosis. We have also measured their oxidative burst response by the nitroblue tetrazolium dye (NBT) reduction method. Our studies revealed that macrophages harvested from chronic alcoholic rats expressed surface C3b and Fc receptors, with significantly higher surface density than macrophages of litter-mate controls (matched for sex and nutritional calories). However, the ability of macrophages from alcoholic rats to phagocytize through C3b and Fc receptors was significantly impaired. In addition, the ability of peritoneal macrophages from alcoholic animals to ingest non-opsonized Candida albicans and to reduce NBT dye was markedly compromised. Abnormalities of macrophage function may, at least in part, account for an increased susceptibility of alcoholic patients to infection.