Effects of eicosapentaenoic acid and docosahexaenoic acid on responses of LPS-stimulated intestinal B lymphocytes from broiler chickens studied in vitro

摘要

Effects of different ratios and concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on intestinal B lymphocyte proliferation, IgA secretion and expression of CD5 + CD79a were studied in vitro using cells isolated from broilers. Proliferation was determined by the 3-(4,5- dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide (MTT) assay, and those groups with significant difference were selected to detect the IgA using ELISA kit. According to the significant difference of IgA secretion, the expression of CD5 and CD79a was analyzed by fluorescent antibody staining and flow cytometry. The results showed that EPA and DHA inhibited the in vitro proliferation of lipopolysaccharide (LPS)-stimulated B lymphocytes. EPA and DHA significantly suppressed the ability of LPS-stimulated B cells to secrete IgA with ratios of 1:1 at 20 μg/mL and 2:1 at 20 and 40 μg/mL (P 0.05). In addition, CD5 and CD79a were maximally expressed on LPS-stimulated B cells when the EPA/DHA ratio was 2:1 at 20 μg/mL (P 0.01), suggesting that the inflammatory reaction may be downregulated by the increasing expression of CD5 and CD79a and inhibitive secretion of IgA by B cell.