Brief Article
Copyright ©2010 Baishideng. All rights reserved
World J Gastroenterol. May 14, 2010; 16(18): 2283-2290
Published online May 14, 2010. doi: 10.3748/wjg.v16.i18.2283
Adhesion and immunomodulatory effects of Bifidobacterium lactis HN019 on intestinal epithelial cells INT-407
Chang Liu, Zhuo-Yang Zhang, Ke Dong, Xiao-Kui Guo
Chang Liu, Zhuo-Yang Zhang, Ke Dong, Xiao-Kui Guo, Department of Medical Microbiology and Parasitology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
Author contributions: Liu C and Zhang ZY performed the majority of experiments; Dong K and Guo XK provided vital reagents and analytical tools and were also involved in editing the manuscript; Guo XK provided financial support for this work; Liu C and Guo XK designed the study and wrote the manuscript.
Supported by (in part) The National Key Program for Infectious Diseases of China, No. 2008ZX10004-002, No. 2008ZX10004-009, and No. 2009ZX10004-712; Program of Shanghai Subject Chief Scientist, No. 09XD1402700
Correspondence to: Xiao-Kui Guo, Professor, Department of Medical Microbiology and Parasitology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China. microbiology@sjtu.edu.cn
Telephone: +86-21-64453285 Fax: +86-21-64453285
Received: January 20, 2010
Revised: February 4, 2010
Accepted: February 11, 2010
Published online: May 14, 2010
Abstract

AIM: To elucidate the adherence and immunomodulatory properties of a probiotic strain Bifidobacterium lactis (B. lactis) HN019.

METHODS: Adhesion assays of B. lactis HN019 and Salmonella typhimurium (S. typhimurium) ATCC 14028 to INT-407 cells were carried out by detecting copies of species-specific genes with real-time polymerase chain reaction. Morphological study was further conducted by transmission electron microscopy. Interleukin-1β (IL-1β), interleukin-8, and tumor necrosis factor-α (TNF-α) gene expression were assessed while enzyme linked immunosorbent assay was used to detect IL-8 protein secretion.

RESULTS: The attachment of S. typhimurium ATCC 14028 to INT407 intestinal epithelial cells was inhibited significantly by B. lactis HN019. B. lactis HN019 could be internalized into the INT-407 cells and attenuated IL-8 mRNA level at both baseline and S. typhimurium-induced pro-inflammatory responses. IL-8 secretion was reduced while IL-1β and TNF-α mRNA expression level remained unchanged at baseline after treated with B. lactis HN019.

CONCLUSION: B. lactis HN019 does not up-regulate the intestinal epithelium expressed pro-inflammatory cytokine, it showed the potential to protect enterocytes from an acute inflammatory response induced by enteropathogen.

Keywords: Probiotics; Intestinal epithelium; Enteropathogen; Immunomodulation; Adhesion