Analysis of Chlamydia pneumoniae infection in mononuclear cells by reverse transcription-PCR targeted to chlamydial gene transcripts
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Chlamydia pneumoniae (C. pneumoniae) is an important etiological agent of respiratory infections including pneumonia. C. pneumoniae DNA can be detected in peripheral blood mononuclear cells indicating that monocytes can assist the spread of infection to other anatomical sites. Persistent infection established at these sites could promote inflammation and enhance pathology. Thus, the mononuclear cells are in a strategic position in the development of persistent infection. To investigate the intracellular replication and fate of C. pneumoniae in mononuclear cells, we have established an in vitro model in the human Mono Mac 6 cell line. In the present study, we analyzed the transcription of 11 C. pneumoniae genes in Mono Mac 6 cells during infection by real-time RT-PCR. Our results suggest that the transcriptional profile of the studied genes in monocytes is different from that seen in epithelial cells. Furthermore, our study shows that genes related to secretion are transcribed, and secreted bacterial proteins are also translated during infection of monocytes, creating novel opportunities for the management of chlamydial infection of monocytes.
KeywordsChlamydia Persistent infection RT-PCR Transcription Mononuclear cells
We thank Ali Mahar and Carola Andersson-Parkkonen for technical assistance with the plasmids and in vitro transcripts used in this work. We would like to thank Prof Guangming Zhong for supplying us with the monoclonal antibody against CPAF. This research was supported by the Academy of Finland (#110340) and in the framework of the ERA-NET PathoGenoMics, #217554/ECIBUG, and #130043/ChlamyTrans. The study was also supported by grants from the Jenny and Antti Wihuri Foundation (EM).
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