Alteration of in vitro human lymphocyte function by ethanol, acetaldehyde and acetate

Infection is a major cause of morbidity and mortality in chronic alcoholics and may be attributable to altered lymphocyte function. To evaluate this possibility, the effects of physiologic concentrations of ethanol (ETH) and its metabolites, acetaldehyde (ACH) and acetate (ACT), were studied using in vitro mononuclear cell cultures prepared from normal human donors. ETH depressed DNA synthesis induced by both phytohemagglutinin-M(PHA) and Concanavalin A (Con A). ACH significantly impaired Con A and PHA stimulated lymphocyte DNA synthesis. Con A and PHA induced blastogenesis was also significantly reduced by the in vitro addition of ACT. Spontaneous lymphocyte transformation in these three-day cultures was not affected by ethanol but was decreased by the addition of high dose acetate and acetaldehyde. Lymphocyte response to candida and trichophyton antigens was significantly depressed by ETH and its metabolites. Monocyte depletion by adherence had no effect on these results. Treatment of lymphocytes with ETH, ACH or ACT did not change T cell binding of sheep erythrocytes or B cell expression of surface immunoglobulin or receptor sites for complement. It is concluded that both ethanol and its metabolites in physiologic concentrations significantly inhibited lymphocyte function without altering surface markers.