Medical Microbiology and Immunology

, Volume 187, Issue 2, pp 115–120

Viability and gene expression in Chlamydia trachomatis during persistent infection of cultured human monocytes

  • Hervé C. Gérard
  • L. Köhler
  • Patrick J. Branigan
  • Henning Zeidler
  • H. Ralph Schumacher
  • Alan P. Hudson
ORIGINAL INVESTIGATION

DOI: 10.1007/s004300050082

Cite this article as:
Gérard, H., Köhler, L., Branigan, P. et al. Med Microbiol Immunol (1998) 187: 115. doi:10.1007/s004300050082

Abstract

The principal host cell for persistently infecting synovial Chlamydia trachomatis is the macrophage. During infection of human monocytes/macrophages in culture this bacterium displays aberrant morphology and produces no new elementary bodies, reflecting the situation in synovium. Here we investigate the metabolic status of C. trachomatis (serovar K) during an extended infection of human peripheral monocytes in vitro. Using reverse transcription-polymerase chain reaction assays, we have shown that primary transcripts from the chlamydial rRNA operons are present throughout a 10-day course of infection. Other assays targeting mRNAs from chlamydial genes encoding r-proteins S5 and L5, the glycyl-tRNA synthetase, the 60-kDa cysteine-rich outer membrane protein, and the KDO transferase indicate that these messengers are also present throughout the entire 10-day period. The gene encoding the 57-kDa heat-shock protein (hsp60) is expressed by the bacterium throughout the 10-day infection of cultured monocytes, but transcript levels from the gene encoding the major outer membrane protein (omp1) appear to be attenuated. Western analyses targeting these latter proteins confirm the presence of the hsp60 gene product, and the virtual absence of major outer membrane protein, in chlamydia-infected cultured human monocytes. Thus, during extended infection of human monocytes in vitro, chlamydia are non-productive but transcriptionally active; the pattern of transcriptional activity reflects that known for persistent C. trachomatis infection in vivo in synovial tissue.

Key words Chlamydia Persistent infection Monocytes Transcription 

Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Hervé C. Gérard
    • 1
  • L. Köhler
    • 2
  • Patrick J. Branigan
    • 3
  • Henning Zeidler
    • 2
  • H. Ralph Schumacher
    • 3
  • Alan P. Hudson
    • 1
  1. 1.Department of Immunology and Microbiology, Wayne State University School of Medicine, Gordon H. Scott Hall, 540 East Canfield Avenue, Detroit, Michigan 48201, USAUS
  2. 2.Abteilung Rheumatologie, Medizinische Hochschule Hannover, Carl Neuberg Strasse 1, D-30625 Hannover, Germany e-mail: Koehler.Lars@MH-Hannover.de, Tel.: +49-511-5325252, Fax: +49-511-5325252DE
  3. 3.Medical Research, Department of Veterans Affairs Medical Center, University and Woodland Avenues, Philadelphia, PA 19104, USAUS

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