抄録
The effect of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on natural killer (NK) cell activity in human peripheral blood lymphocytes (PBL) was studied. The direct addition of trieicosa-pentaenoyl-glycerol (EPA-TG) or tridocosahexaenoil-glycerol (DHA-TG) emulsion to a cytotoxicity assay system significantly suppressed NK cell activity. The addition of a lipoxygenase inhibitor AA861 also inhibited NK cell activity. The inhibition was proportional to the concentraton of EPA-TG emulsion, DHA-TG emulsion or AA861. The inhibitory effect caused by these lipids or lipoxygenase blockade could not be reversed by adding back exogenous leukotrienes to the assay system. Preincubation of reflector cells with EPA-TG or DHA-TG emulsion resulted in a significant inhibition of their NK cell activity. NK cell activity of human lymphocytes was markedly decreased after the EPA-TG emulsion infusion in healthy volunteers. Thus, in vivo use of EPA-TG or DHA-TG emulsion may influence immune reactivity of the host, although the mechanism has not yet been elucidated.