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Potential implication of new torque teno mini viruses in parapneumonic empyema in children

Johanna Galmès1, Yongjun Li, Alain Rajoharison

  • 1Laboratoire des Pathoge`nes Emergents, Fondation Me´rieux, Lyon, France.

The European Respiratory Journal
|October 13, 2012
PubMed

Insights

New torque teno mini virus (TTMV) isolates were found in children with severe pneumonia and parapneumonic empyema (PPE). These TTMV strains replicate in lung cells and trigger an immune response, suggesting a role in pneumonia's development.

Area of Science:

  • Virology
  • Infectious Diseases
  • Molecular Biology

Background:

  • Recent years have seen an unexplained rise in parapneumonic empyema (PPE) cases associated with pneumonia.
  • The etiology of severe pneumonia with PPE in children remains incompletely understood.

Purpose of the Study:

  • To investigate the genetic and biological characteristics of novel torque teno mini virus (TTMV) isolates from children with severe pneumonia and PPE.
  • To explore the potential role of these new TTMV isolates in the pathogenesis of pneumonia.

Main Methods:

  • Pathogen discovery protocol applied to undiagnosed pleural effusion samples.
  • Identification and isolation of three new TTMV strains (TTMV-LY).
  • In vitro replication studies in A549 and HEK293T cells using genome transfection and viral particle infection.
  • Quantitative real-time PCR, full-length genome amplification, and multiplex immunoassay for immune response assessment.

Main Results:

  • Three novel TTMV-LY isolates were identified, exhibiting classic genomic organization but low sequence identity (<64%) to known TTMV.
  • Demonstrated in vitro replication of TTMV-LY in alveolar epithelial cells and release of infectious virions.
  • TTMV-LY infection selectively induced the production of inflammatory mediators.

Conclusions:

  • This study describes replicative TTMV-LY strains isolated from pediatric parapneumonic effusions.
  • The findings suggest a potential etiological role for these novel TTMV isolates in the pathogenesis of severe pneumonia with PPE.

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