ABSTRACT: We investigated the transcriptome response of porcine intestinal epitheliocyte cell line (PIE cells) to the challenge with the Toll-like receptor 3 (TLR3) agonist poly(I:C) and, the changes induced by immunobiotic Lactobacillus rhamnosus CRL1505 (Lr1505) or Lactobacillus plantarum CRL1505 (Lp1506) in that response. The transcriptome approach allowed us to obtain a global overview of the immune and immune related genes involved in response of PIE cells to the viral pathogen-associated molecular pattern poly(I:C). The most remarkable changes in PIE cells after Poly(:IC) challenge were observed in type I interferons and, interferon-induced genes, cytokines and chemokines expressions, followed by cell adhesion molecules and, prostaglandins. Previous work demonstrated in vitro and in vivo the capacity of both Lr1505 and Lp1506 to improve antiviral immunity. Here, we also confirmed that both immunobiotic lactobacilli differently modulates gene expression in poly(I:C)-challenged PIE cells. The microarray gene expression profiles demonstrated that Lr1505 and Lp1506 increased the expression of type I interferons as well as the antiviral factors MX1, MX2, OAS1, OASL, RNASE4 and RNASEL. In addition, lactobacilli were able to significantly improve the expression of cytokines (IL-1β, IL-6), chemokines (AMCF-II, CCL20, CCL28, CCL4, CXCL10, CXCL11) and, adhesion molecules (SEL-E, SEL-L, EPCAM, ICAM-1). Of interest, both Lr1505 and Lp1506 differentially modulated the expression of several genes related to prostaglandins including PTGS2, PTGIR, PTGES and, PTGFRN. The results show the ability of Lr1505 and Lp1506 to increase cellular factors involved in innate antiviral immunity that would explain their capacity to increase resistance to viral challenges observed in animal models. In addition, Lr1505 and Lp1506 may potentiate antiviral immunity by promoting the recruitment and activation of immune cells via the factors produced by the epithelial cells. The comprehensive analysis of gene expression in PIE cells by microarray allowed an important advance in the understanding of the mechanisms of action involved in the antiviral effect of immunobiotic lactobacilli.
