[Bifidobacterium cell wall proteins induced beta-defensin 2 mRNA expression in human intestinal epithelial cells].
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.


CONCLUSIONS
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.
Wang
Guoxing
G
Research Unit of Infection & Immunity, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, China.
Feng
Yun
Y
Wang
Yuhui
Y
Huang
Ning
N
Wu
Qi
Q
Wang
Boyao
B
D001426:Bacterial Proteins / Q000494:pharmacology*; D001644:Bifidobacterium / Q000166:cytology*; D004847:Epithelial Cells / Q000378:metabolism*; D006801:Humans; D007422:Intestines / Q000166:cytology; D008565:Membrane Proteins / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D023083:beta-Defensins / Q000096:biosynthesis* / Q000235:genetics
D001426:Bacterial Proteins; C106641:DEFB4A protein, human; D008565:Membrane Proteins; D012333:RNA, Messenger; D023083:beta-Defensins