Social drinking and the immune response: impairment of lymphokine-activated killer activity

The effect of limited and intermittent alcohol ingestion on the immune response in humans has not been extensively studied. The authors, in this study, evaluate peripheral blood mononuclear cell cytotoxicity before and after alcohol ingestion in a setting designed to mimic social drinking. Eleven healthy volunteers consumed two 12 oz (355 mL) cans of beer in 30 minutes while eating pizza. Five control individuals ingested non-alcoholic beverages. Natural killer and lymphokine-activated killer activity were determined for peripheral blood mononuclear cells obtained before and 30 minutes after alcohol ingestion. Interleukin 2-induced lymphokine-activated killer activity was significantly reduced in blood samples obtained after alcohol ingestion when compared with pre-alcohol samples (p < 0.01). Natural killer activity (unstimulated) was not affected by alcohol ingestion. The authors demonstrate that ingestion of a small amount of alcohol impairs the cytotoxic capacity of peripheral blood mononuclear cells. Alcohol in the context of social drinking may have deleterious effects on the immune system's ability to clear virus-infected cells or cells that have undergone neoplastic transformation, especially for individuals with pre-existing immunosuppression.