Immunomodulatory effects of live and pasteurized Lactobacillus crispatus strain RIGLD-1 on Helicobacter pylori-triggered inflammation in gastric epithelial cells in vitro

BackgroundHelicobacter pylori infection is considered as the major risk factor for gastric adenocarcinoma. Today, the increasing emergence of antibiotic-resistant strains has drastically decreased the eradication rate of H. pylori infection. This study was aimed to investigate the inhibitory and modulatory effects of live and pasteurized Lactobacillus crispatus strain RIGLD-1 on H. pylori adhesion, invasion, and inflammatory response in AGS cell line.Methods and resultsThe probiotic potential and properties of L. crispatus were evaluated using several functional and safety tests. Cell viability of AGS cells exposed to varying concentrations of live and pasteurized L. crispatus was assessed by MTT assay. The adhesion and invasion abilities of H. pylori exposed to either live or pasteurized L. crispatus were examined by gentamycin protection assay. The mRNA expression of IL-1 & beta;, IL-6, IL-8, TNF-& alpha;, IL-10, and TGF-ss genes was determined by RT-qPCR from coinfected AGS cells. ELISA was used for the detection of IL-8 secretion from treated cells. Both live and pasteurized L. crispatus significantly decreased H. pylori adhesion/invasion to AGS cells. In addition, both live and pasteurized L. crispatus modulated H. pylori-induced inflammation by downregulating the mRNA expression of IL-1 & beta;, IL-6, IL-8, and TNF-& alpha; and upregulating the expression of IL-10, and TGF-ss cytokines in AGS cells. Furthermore, H. pylori-induced IL-8 production was dramatically decreased after treatment with live and pasteurized L. crispatus.ConclusionsIn conclusion, our findings demonstrated that live and pasteurized L. crispatus strain RIGLD-1 are safe, and could be suggested as a potential probiotic candidate against H. pylori colonization and inflammation.