Helicobacter pylori induces apoptosis of human monocytes but not monocyte-derived dendritic cells: role of the cag pathogenicity island.
Journal Article
Monocytes are circulating precursors of the dendritic cell subset, professional antigen-presenting cells with a unique ability to initiate the innate and adaptive immune response. In this study, we have investigated the effects of wild-type Helicobacter pylori strains and their isogenic mutants with mutations in known bacterial virulence factors on monocytes and monocyte-derived dendritic cells. We show that H. pylori strains induce apoptosis of human monocytes by a mechanism that is dependent on the expression of a functional cag pathogenicity island. This effect requires an intact injection organelle for direct contact between monocytes and the bacteria but also requires a still-unidentified effector that is different from VacA or CagA. The exposure of in vitro-generated monocyte-derived dendritic cells to H. pylori stimulates the release of inflammatory cytokines by a similar mechanism. Of note is that dendritic cells are resistant to H. pylori-induced apoptosis. These phenomena may play a critical role in the evasion of the immune response by H. pylori, contributing to the persistence of the infection.
Full Text
Duke Authors
Cited Authors
- Galgani, M; Busiello, I; Censini, S; Zappacosta, S; Racioppi, L; Zarrilli, R
Published Date
- August 2004
Published In
Volume / Issue
- 72 / 8
Start / End Page
- 4480 - 4485
PubMed ID
- 15271906
Pubmed Central ID
- 15271906
International Standard Serial Number (ISSN)
- 0019-9567
Digital Object Identifier (DOI)
- 10.1128/IAI.72.8.4480-4485.2004
Language
- eng
Conference Location
- United States