The selective effect of dietary n-3 polyunsaturated fatty acids on murine Th1 and Th2 cell development
Abstract
To examine how dietary n-3 polyunsaturated fatty acids affect Th2 cell development, female C57BL/6 mice were fed a washout corn oil (CO) diet for 1 wk followed by 2 wk of either the same CO diet or a fish oil (FO) diet. CD4+ T cells were isolated from spleens and cultured under both neutral (anti-CD3 and phorbol myristate acetate (PMA)) and Th2 polarizing conditions (anti-CD3 and PMA, in presence of rIL-4, rIL-2, and anti-IFN-ó) in the presence of homologous mouse serum (HMS) or fetal bovine serum (FBS) for 2 d. Dietary n-3 PUFA significantly enhanced Th2 cell development and suppressed Th1 development under neutral conditions as assessed by intracellular cytokine staining for IL-4 and IFN-ó as the two prototypic Th2 and Th1 cytokines, respectively. However, under Th2 polarizing conditions, while the suppression of Th1 cells was maintained in FO-fed mice, no dietary effect was observed in Th2 cells. Dietary FO increased the Th2/Th1 ratio under both neutral and Th2 polarizing conditions with HMS in the cultures. To examine the effect of dietary n-3 PUFA on Th1 development, DO11.10 Rag2-/- mice expressing transgenic T cell receptor specific for ovalbumin (OVA) peptide were used. CD4+ T cells were isolated from spleens and lymph nodes and stimulated with ovalbumin (OVA) peptide and irradiated BALB/c splenocytes in the presence of rIL-12, anti-IL-4, and rIL-2 in HMS for 2d. Cells were expanded for another 3 d in the presence of rIL-2 and rIL-12. Dietary n-3 PUFA did not affect Th1 differentiation as assessed by the proportion of IFN-ó+, IL-4- T cells in the cultures, but suppressed rIL-2 induced expansion. The suppressed expansion was due to suppressed proliferation (p<0.05). In vivo expansion of antigen-specific T cells was visualized by flow cytometric analysis of CFSE-positive transgenic T cells. Dietary n-3 PUFA did not appear to affect antigen-induced CD4+ T cell cycle progression in vivo. Overall, these results suggest dietary n-3 PUFA have no direct effect on Th2 cell development but do directly suppress Th1 cell development following both mitogenic and antigenic stimulation in vitro.
Citation
Zhang, Ping (2005). The selective effect of dietary n-3 polyunsaturated fatty acids on murine Th1 and Th2 cell development. Doctoral dissertation, Texas A&M University. Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /4148.