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Published on: April 9, 2019
[Bifidobacterium cell wall proteins induced beta-defensin 2 mRNA expression in human intestinal epithelial cells]
Guoxing Wang1, Yun Feng, Yuhui Wang
1Research Unit of Infection & Immunity, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, China.
Objective:
To examine Bifidobacterium mediated induction of human defensin 2 mRNA expression in human intestinal epithelial cells and define the bioactive components of Bifidobacterium.
Methods:
Bifidobacterium was cultured in MRS medium in anaerobic incubator and its cell wall was isolated by sonication and centrifugation. The cell wall proteins of Bifidobacteria were extracted with 2% SDS. The level of hBD-2 mRNA in HT-29 cells was detected by reverse-transcription PCR and Northern blot analysis.
Results:
There was no detectable signal of hBD-2 mRNA in the unstimulated HT-29 cells. However, the heat-killed Bifidobacteria, cell wall of Bifidobacteria, and cell wall proteins remarkably induced hBD-2 mRNA expression in HT-29.
Conclusion:
Bifidobacterium or its cell wall proteins can induce hBD-2 gene expression in human intestinal epithelial cells, which may play a role in the mechanisms of innate defense against pathogens in the intestine.
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