Back to Search
Start Over
Pilus-mediated epithelial cell death in response to infection with Burkholderia cenocepacia.
- Source :
-
Microbes and infection [Microbes Infect] 2007 Jun; Vol. 9 (7), pp. 829-37. Date of Electronic Publication: 2007 Mar 12. - Publication Year :
- 2007
-
Abstract
- Burkholderia cenocepacia is an opportunistic pathogen that can cause serious infections in cystic fibrosis (CF) patients. The ET12 lineage appears particularly virulent in CF; however, its pathogenesis is poorly understood and may be associated with host response. To help characterize this response, the ability of B. cenocepacia to induce cytotoxicity and apoptosis in an epithelial cell model was examined. Upon infection with B. cenocepacia strain K56-2, A549 human lung epithelial cells underwent significant cell death; propidium iodine staining and DNA fragmentation assays suggested apoptosis. Initiation of cell death was independent of the type III secretion system, biofilm formation, and secreted bacterial cytotoxins. However, the frequency of cell death was lower in cells infected with a non-piliated mutant, K56-2 cblA::Tp. Furthermore, purified cbl pili were found to directly induce cytotoxicity in A549 cells and activate caspase-9, -8, -7, and -3, the major cysteine proteinases involved in apoptosis. It appears that B. cenocepacia cbl pili, which are a distinctive feature of the ET12 lineage, act as an initiator of cytotoxicity and apoptosis. Understanding the role of cbl pili in the pathogenesis of B. cenocepacia infections offers the potential for decreasing the virulence of these potentially life-threatening organisms in CF patients.
- Subjects :
- Annexin A5 chemistry
Blotting, Western
Burkholderia Infections microbiology
Burkholderia cepacia complex growth & development
Burkholderia cepacia complex metabolism
Caspases metabolism
Cell Line
Cell Survival physiology
Cystic Fibrosis pathology
DNA Fragmentation
Epithelial Cells metabolism
Epithelial Cells pathology
Flow Cytometry
Humans
Microscopy, Fluorescence
Propidium chemistry
Apoptosis physiology
Burkholderia Infections pathology
Burkholderia cepacia complex pathogenicity
Cystic Fibrosis microbiology
Fimbriae, Bacterial pathology
Subjects
Details
- Language :
- English
- ISSN :
- 1286-4579
- Volume :
- 9
- Issue :
- 7
- Database :
- MEDLINE
- Journal :
- Microbes and infection
- Publication Type :
- Academic Journal
- Accession number :
- 17537663
- Full Text :
- https://doi.org/10.1016/j.micinf.2007.03.001