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Updated: Feb 24, 2026

Invasion of Human Cells by a Bacterial Pathogen
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Invasion of Human Cells by a Bacterial Pathogen

Published on: March 21, 2011

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Streptococcus pyogenes translocates across an epithelial barrier

Tomoko Sumitomo1

  • 1Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry.

Nihon Saikingaku Zasshi. Japanese Journal of Bacteriology
|August 29, 2017
PubMed

Insights

Streptococcus pyogenes invades tissues by degrading cell junctions using streptolysin S and SpeB. The bacteria also use host plasminogen to speed up invasion through tricellular tight junctions.

Area of Science:

  • Microbiology
  • Cell Biology
  • Infectious Diseases

Background:

  • Streptococcus pyogenes causes pharyngeal and skin infections.
  • Invasive S. pyogenes infections are rare but have high mortality.
  • Bacterial translocation across epithelial barriers is crucial for invasive disease.

Purpose of the Study:

  • To identify factors enabling Streptococcus pyogenes translocation across epithelial barriers.
  • To elucidate the mechanisms of bacterial invasion into deeper tissues.

Main Methods:

  • Investigated bacterial translocation mechanisms of Streptococcus pyogenes.
  • Identified bacterial factors and host interactions facilitating invasion.

Main Results:

  • Streptolysin S and SpeB facilitate bacterial translocation by degrading intercellular junctions.
  • S. pyogenes exploits host plasminogen to accelerate invasion via tricellular tight junctions.

Conclusions:

  • Novel factors, streptolysin S and SpeB, enable S. pyogenes epithelial barrier translocation.
  • Host plasminogen is exploited by S. pyogenes to enhance invasion through tricellular tight junctions.
  • Understanding these mechanisms is key to combating invasive streptococcal infections.

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