Immune Responses to Ethanol Metabolites and Cytokine Profiles Differentiate Alcoholics with or without Liver Disease

Excessive alcohol consumption is associated with the generation of antibodies against neoantigens induced by ethanol metabolism. However, the associations between such immune responses, ethanol consumption, and liver injury remain unclear.

Eight-six male alcoholics with (n=54) or without (n=32) liver disease, and 20 male volunteers (6 abstainers, 14 moderate drinkers) underwent clinical, morphological, and biochemical assessments of liver status and ethanol consumption.

Antiacetaldehyde adduct IgAs in both groups of alcoholics were significantly higher than those in the controls. Elevated IgGs occurred in patients with liver disease, whereas IgMs were high in the heavy drinkers without apparent liver disease. Liver disease patients had high levels of both proinflammatory (IL-2, IL-6, IL-8, TNF-alpha) and antiinflammatory (IL-10) cytokines, whereas those without liver disease showed elevated IL-6, IL-8, and IL-10 only. Ethanol consumption correlated significantly with antiadduct IgA and IL-6 levels, which also showed parallel changes upon abstinence.

Alcoholic liver disease is associated with the generation of IgAs and IgGs against acetaldehyde-derived antigens and enhanced levels of both pro- and antiinflammatory cytokines, whereas elevated IgA, IL-6, and IL-10 characterize alcoholics without liver disease. These data suggest that immunological mechanisms may play a role in the sequence of events leading to liver disease in some patients with excessive drinking.