In:
Infection and Immunity, American Society for Microbiology, Vol. 71, No. 10 ( 2003-10), p. 5979-5985
Abstract:
Parachlamydia acanthamoeba is an obligately intracellular bacterium that naturally infects free-living amoebae. It is a potential human pathogen and may survive in human macrophages. We studied P. acanthamoeba entry into, and multiplication within, human monocyte-derived macrophages. After 8 h of incubation, 80% of macrophages were infected with a mean of 3.8 P. acanthamoeba organisms per cell. Electron microscopy demonstrated that parachlamydiae were in an intracellular vacuole. After infection with living organisms, the number of parachlamydiae per macrophage increased 4 times from day 0 to day 4, whereas heat-inactivated parachlamydiae were eliminated during the same period. Quantitative PCR confirmed that P. acanthamoeba replicates within macrophages. Transcriptional activity of P. acanthamoeba was detected by reverse transcription-PCR targeting the gene encoding ADP-ATP translocase ( tlc ). P. acanthamoeba exerted a cytopathic effect on macrophages. When macrophages were infected with living bacteria, their number decreased significantly from day 0 to day 4 due to apoptosis, as shown by annexin-V binding and electron microscopy. This study shows that P. acanthamoeba enters and multiplies within human macrophages before inducing their apoptosis.
Type of Medium:
Online Resource
ISSN:
0019-9567
,
1098-5522
DOI:
10.1128/IAI.71.10.5979-5985.2003
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2003
detail.hit.zdb_id:
1483247-1
detail.hit.zdb_id:
218698-6
