Interaction of TGF-β4 and IL-17 with IgA secretion in the intestine of chickens fed with E. faecium AL41 and challenged with S. Enteritidis.

The relative mRNA expression of IgA, TGF-β4, IL-17, and concentration of secretory IgA (sIgA) in small intestine of chickens pretreated with Enterococcus faecium AL41 and challenged with Salmonella Enteritidis PT4 were studied. Salmonella-free day-old chicks (40) Cobb 500 breed, were divided into four groups of 10 chicks each (n = 10): control (C), treated with E. faecium AL41 strain (EFAL41), challenged with Salmonella Enteritidis PT4 (SE), and combined (EFAL41+SE). Expression of IgA and sIgA concentration was upregulated in EFAL41 group in jejunum and ileum on 4 days post-Salmonella infection (dpi). Chicks in combined group demonstrated upregulation of cytokines and IgA expression, and increased sIgA concentration in the intestine flush on 7 dpi. The experiment demonstrated beneficial effect of E. faecium AL41 on IgA production and secretion in intestine. Findings also indicated that IgA played important role in decrease of S. Enteritidis in the intestine, and cytokines TGF-β4 and IL-17 contributed to the increased IgA secretion.