In vitro adhesion and anti‐inflammatory properties of native Lactobacillus fermentum and Lactobacillus delbrueckii spp

Aims This study aimed at characterizing the adhesion and immune‐stimulatory properties of native probiotic Lactobacillus fermentum (MCC 2759 and MCC 2760) and Lactobacillus delbrueckii MCC 2775. Methods and Results Adhesion of the strains was assessed in Caco‐2 and HT‐29 cell lines. Expression of adhesion and immune markers were evaluated in Caco‐2 cells by real‐time qPCR. The cultures displayed >80% of adhesion to both cell lines and also induced the expression of mucin‐binding protein (mub) gene in the presence of mucin, bile and pancreatin. Adhesion was mediated by carbohydrate and proteinaceous factors. The cultures stimulated the expression of inflammatory cytokines in Caco‐2 cells. However, pro‐inflammatory genes were down‐regulated upon challenge with lipopolysaccharide and IL‐10 was up‐regulated by the cultures. Cell wall extract of L. fermentum MCC 2760 induced the expression of IL‐6 by 5·47‐fold, whereas crude culture filtrate enhanced the expression of IL‐10 by 14·87‐fold compared to LPS control. Conclusions The bacterial cultures exhibited strong adhesion and anti‐inflammatory properties. Significance and Impact of the Study This is the first report to reveal the role of adhesion markers of L. fermentum and L. delbrueckii by qPCR. The strain‐specific anti‐inflammatory property of native cultures may be useful to alleviate inflammatory conditions and develop a target‐based probiotic.