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Immuno-fluorescence Assay of Leptospiral Surface-exposed Proteins
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[Association of fliR gene in Leptospira interrogans with adhesion and pathogenicity to host cells]

Ping Ruan1, Xin-ying Wang, Ai-hua Sun

  • 1Medical School of Shaoxing University, Shaoxing 312000, China.

Zhejiang Da Xue Xue Bao. Yi Xue Ban = Journal of Zhejiang University. Medical Sciences
|December 17, 2008
PubMed
Abstract

Insights

The Leptospira interrogans fliR gene is crucial for bacterial adhesion and pathogenicity, as demonstrated by gene knockout and silencing experiments. Disabling fliR significantly reduced the bacteria

Area of Science:

  • Microbiology
  • Molecular Biology
  • Pathogenesis

Background:

  • Leptospira interrogans is a bacterial pathogen responsible for leptospirosis.
  • The fliR gene's role in L. interrogans pathogenicity remains incompletely understood.

Purpose of the Study:

  • To investigate the pathogenicity of the Leptospira interrogans fliR gene.
  • To determine the fliR gene's contribution to bacterial adhesion and host cell damage.

Main Methods:

  • Constructed fliR gene knockout (56601fliR-Kana) and siRNA-mediated gene silencing (56601siRNA-R2) mutants of L. interrogans.
  • Assessed bacterial adhesion to J774A.1 cells using adhesion assays.
  • Evaluated the induction of cell necrosis and apoptosis via flow cytometry.

Main Results:

  • Both 56601fliR-Kana and 56601siRNA-R2 mutants showed significantly reduced mRNA levels of the fliR gene.
  • These mutants exhibited a marked decrease in their ability to adhere to J774A.1 cells.
  • The induction of cell necrosis and apoptosis by the mutants was significantly weakened compared to the wild-type strain.

Conclusions:

  • The fliR gene is a virulence-associated factor in L. interrogans.
  • fliR plays a critical role in bacterial adhesion to host cells.
  • The gene is involved in inducing host cell necrosis and apoptosis, contributing to L. interrogans pathogenicity.

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