Parachlamydia acanthamoebae enters and multiplies within pneumocytes and lung fibroblasts

Details

Serval ID
serval:BIB_397B1AA9E66E
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Parachlamydia acanthamoebae enters and multiplies within pneumocytes and lung fibroblasts
Journal
Microbes and Infection
Author(s)
Casson  N., Medico  N., Bille  J., Greub  G.
ISSN
1286-4579
Publication state
Published
Issued date
04/2006
Peer-reviewed
Oui
Volume
8
Number
5
Pages
1294-300
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Apr
Abstract
Parachlamydia acanthamoebae is a Chlamydia-like organism that naturally infects free-living amoebae. P. acanthamoebae is a putative emerging agent of community-acquired and inhalation pneumonia that may enter and multiply within human macrophages. However, since Parachlamydia induces their apoptosis, macrophages may not represent a perennial niche for this obligate intracellular bacterium. Therefore, we investigated whether pneumocytes and lung fibroblasts are permissive to Parachlamydia infection and might act as a replicative niche. Entry of Parachlamydia into pneumocytes (A549) and lung fibroblasts (HEL) was confirmed by confocal and electron microscopy. In A549 cells, the mean number of Parachlamydia per cell increased 7-fold from day 0 to day 7, independently of the technique used to label the bacteria. The proportion of infected A549 cells also increased over time, whereas cell viability remained unaffected by Parachlamydia infection. The sustained (3 weeks) viability of Parachlamydia when incubated in the presence of A549 cells contrasted with that observed in the absence of cells. HEL cells were also permissive to Parachlamydia infection, as we observed a 3- to 4-fold increase in the mean number of bacteria per cell. In HEL cells, Parachlamydia retained some viability for 2 weeks. These findings demonstrate that Parachlamydia is able to enter and multiply within pneumocytes and fibroblasts. The viability of both cell types was not compromised after Parachlamydia infection. We therefore conclude that these cells may remain infected for a prolonged time and may represent an intrapulmonary niche for the strictly intracellular Parachlamydia. This indirectly supports the role of Parachlamydia as an agent of pneumonia.
Keywords
Acanthamoeba/*microbiology Animals Cell Line Cell Line, Tumor Chlamydiales/*growth & development/*pathogenicity/physiology Fibroblasts/*microbiology Humans Lung/*cytology/*microbiology Mice Microscopy, Confocal
Pubmed
Web of science
Create date
11/02/2008 13:40
Last modification date
20/08/2019 14:29
Usage data