Dietary polyunsaturated fatty acid effects on immune cells of the porcine lung.

The effects of various dietary polyunsaturated fatty acids (PUFAs) on the function of immune cells of the porcine lung was studied. Groups of six pigs were fed diets containing 10.5% corn oil (CO; enriched in linoleic acid (18:2, n-6)), linseed oil (LO; enriched in a-linolenic acid (18:3, n-3)), menhaden oil (MO; enriched in ei- cosapentaenoic (20:5; n-3) and docosahexaenoic (22:6; n-3) acids), linseed -4- corn oil (1:1; LC), and menhaden + corn oil (1:1; MC) for 28-30 days. Basal levels of alveo- lar macrophage (m4) tumor necrosis factor-a (TNF-a) production were higher (P < .05) for LC- and MC-fed pigs than for CO- and LO-fed pigs. Lipopolysaccharide (LPS)-stimulated LC and MC ms produced more TNF than mgs from pigs fed CO, LO, and MO diets. Macro- phages from pigs receiving the CO and LC diets had higher (P < .05) levels of leucine aminopeptidase than mqs from the other dietary groups. Lipopolysaccharide did not increase mnitrite production over basal levels except in the MO diet group. However, LPS-stimulated mcbs from the CO, MO, and LC dietary groups produced more nitrite than mcbs from MC-fed pigs. Alveolar lym- phocytes from pigs receiving the MC diet produced more T cell growth factors than LO and MO m4s. Alveolar m4s from the different dietary groups did not differ in their capacity for non-immune-mediated phagocytosis of