Influence of enteral diets supplemented with key nutrients on lymphocyte subpopulations in Peyer's patches of endotoxin-boostered mice

Background and aims: This study was undertaken to compare the effect of different key nutrients on lymphocyte subsets of Peyer's patches (PP) and spleen in endotoxemic mice. Methods: Female Balb/c mice were fed over a period of 10 days either with an isocaloric and isonitrogenous control diet (Control), a glutamine enriched diet (Diet I) or a diet containing glutamine, arginine, glycine, and n-3 fatty acids (Diet II). On day 7 the mice were challenged intraperitoneally with 25 mu g LPS. The lymphocyte subpopulations (B cells, T cells, CD4+ and CD8+) of PP and spleen were analysed by flow cytometry. Glutathione content of small intestinal mucosa and spleen was determined by HPLC and luminal small intestinal IgA by ELISA. Results: Both experimental diets increased the number of B and T cells in the PP and that of T cells in the spleen (P < 0.01). Glutathione content in PP and spleen was higher under administration of key nutrients (P < 0.05). Diet II reduced luminal small intestinal IgA content in comparison to the two other groups. Conclusion: The addition of arginine, glycine and n-3 fatty acids to a glutamine supplemented diet does not enhance lymphocyte numbers in PP and spleen, but reduces intestinal IgA content. (C) 2000 Harcourt Publishers Ltd.