Essential fatty acid deficiency, prostaglandin synthesis and humoral immunity in Lewis rats.

Essential fatty acid (EFA) deficiency is known to alter the immune response in several experimental systems. To further evaluate the effects of EFAs on immunity Lewis rats were fed diets either adequate or deficient in EFAs for 70-80 days. EFA-adequate rats responded to an i.v. injection of 5 X 10(8) sheep erythrocytes with a sharp, short-lived rise in splenic levels of PGE and PGF within 2 minutes after injection. EFA deficiency resulted in a diminution of this PG response. PG production in liver homogenates was also depressed in EFA-deficient liver. An i.v. injection of sheep erythrocytes resulted in a humoral response against this antigen, measured as hemolytic plaque-forming cells in the spleen. EFA deficiency, as well as pretreatment of EFA-adequate rats with indomethacin, an inhibitor of PG synthesis, resulted in a stimulation of the plaque-forming cell response over that observed in control, EFA-adequate rats. The alterations in immune response resulting from changes in PG synthetic capacity may be important in the etiology of certain immunodeficiency syndromes such as the lupus-erythematosus-like autoimmune disease in NZB/W mice.