Format

Send to

Choose Destination
Microb Pathog. 2009 Oct;47(4):231-6. doi: 10.1016/j.micpath.2009.08.002. Epub 2009 Aug 13.

Inhibition of heat shock protein expression by Helicobacter pylori.

Author information

1
Center for Comparative Medicine, University of California, Davis, CA 95616, USA.

Abstract

Heat shock proteins (HSPs) are primarily known as molecular chaperones that are induced by cell stress and prevent protein aggregation and facilitate folding. Recent evidence suggests that exposure of cells to microbial pathogens can also induce HSPs, which then modulate both innate and adaptive immune responses. Paradoxically, Helicobacter pylori has been found to decrease expression of HSPs. We sought to investigate this phenomenon further and to examine the role of different H. pylori strains and recognized virulence factors in cell culture and in the mouse model. Co-culture of H. pylori with two gastric carcinoma cell lines reduced expression of HSP70 and, to a lesser extent, HSP60. Down modulation of HSPs was not dependent on the presence of the vacuolating cytotoxin (VacA) or the cag pathogenicity island (cag PAI). C57BL/6 mice infected with a human H. pylori strain also demonstrated reduced expression of HSP70, HSP8, and heat shock factor 1 (HSF-1), a transcriptional activator of HSP70. In contrast, the bacterial pathogen, S. Typhimurium up-regulated HSP expression. Since HSPs are thought to function as danger signals during microbial infection, H. pylori down-regulation of HSPs may be a mechanism of immune evasion that promotes chronic infection.

PMID:
19683049
PMCID:
PMC5494282
DOI:
10.1016/j.micpath.2009.08.002
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center