Oral Supplementation With Selected Lactobacillus Acidophilus Triggers Antimicrobial Response, Activation of Innate Lymphoid Cells Type 3 And Improves Colitis

Abstract Live biotherapeutic products constitute an emerging therapeutic approach to prevent or treat inflammatory bowel diseases. Lactobacillus acidophilus is a constituent of the human microbiota with probiotic potential, that are illustrated by direct and indirect antimicrobial activity against several pathogens and improvement of intestinal inflammation. In this study, we evaluated the anti-inflammatory properties of the L. acidophilus strain BIO5768 and assessed the underlying mechanisms of action. BIO5768 was able to counteract the acute colitis that is induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). When administered alone or in combination with Bifidobacterium animalis spp. lactis BIO5764 and Limosilactobacillus reuteri, BIO5768 was also able to alleviate intestinal inflammation induced by Citrobacter rodentium infection. Supplementation of naïve mice with either strain BIO5768 alone or as mixture, increased the gene expression of several target genes involved in immune signaling, including c-type lectin Reg3 gamma. Consistently, the ability of innate lymphoid cells to secrete IL-22 was enhanced in response to BIO5768. Interestingly, the aforementioned responses were shown to be independent of NOD2 and Th17 signaling in mice that were mono-colonized with BIO5768. In conclusion, we identify a new potential probiotic strain with the ability for the management of inflammatory bowel diseases, and provide some insights into its mode of action.