SELECTIVE EFFECT OF ALCOHOL ON CELLULAR IMMUNE-RESPONSES OF LYMPHOCYTES FROM AIDS PATIENTS

In this study we examined the in vitro effects of alcohol on the proliferative responses of lymphocytes from healthy donors and AIDS patients to a recombinant fusion peptide, env-gag, corresponding to portions of the gp 41 envelope (env) and internal core (gag) proteins of HIV. The effects of alcohol (ETOH) on the natural killer (NK) cell activities of lymphocytes from healthy donors and patients with AIDS were also investigated. Peripheral blood mononuclear cells from both normal donors and AIDS patients produced significant levels of lymphocyte proliferative responses to the HIV env-gag peptide; however, these responses were significantly higher in patients with AIDS, showing the specificity of the response. The env-gag-induced proliferative responses of lymphocytes from normal subjects were significantly suppressed when cultures contained only higher levels of ETOH (0.2% and 0.3%), whereas ETOH even at a lower level (0.1%) produced significant suppression of the env-gag-induced proliferation of lymphocytes only from AIDS patients. Direct addition of ETOH at concentrations of 0.1%, 0.2%, and 0.3% to cultures of lymphocytes from normal donors and NK target cells did not produce significant suppression of NK cell activities. However, ETOH at concentrations of 0.2% and 0.3% significantly suppressed the NK activities of lymphocytes from AIDS patients, and the suppressive effect was observed at all E:T cell ratios examined. Control peptide from the Escherichia coli expression vector did not produce any significant effect on lymphocyte proliferative responses or NK activity of both normal donors and AIDS patients. ETOH at various concentrations (0.1%, 0.2%, and 0.3%) or env-gag (10 ng/ml), when individually added to cultures of NK effector and target cells and allowed to remain throughout the 4-h assay period, produced no significant suppression of the NK activity of normal lymphocytes. This suggests a selective inhibitory effect of ETOH on lymphocyte proliferative responses and NK activity of lymphocytes from AIDS patients. Thus ETOH at intoxicating levels may have immunomodulatory effects on the host's immune responses to HIV infection.