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STUDIES ON A CERTAIN SPREADING FACTOR EXISTING IN BACTERIA AND ITS SIGNIFICANCE FOR BACTERIAL INVASIVENESS

F Duran-Reynals1

  • 1Laboratories of The Rockefeller Institute for Medical Research.

The Journal of Experimental Medicine
|October 30, 2009
PubMed

Insights

Invasive bacteria like Staphylococcus and Streptococcus produce a soluble factor that increases tissue permeability, worsening infections. This factor, absent in non-invasive strains, enhances susceptibility to various pathogens and viruses.

Area of Science:

  • Microbiology
  • Immunology
  • Pathogenesis

Background:

  • Invasive bacterial strains, specifically Staphylococcus and Streptococcus, are associated with severe infections.
  • Understanding the mechanisms behind bacterial invasiveness and infection enhancement is crucial for developing effective treatments.

Purpose of the Study:

  • To identify and characterize a soluble factor produced by invasive bacteria.
  • To investigate the role of this factor in increasing tissue permeability and enhancing infections.
  • To compare the properties of this bacterial factor with known spreading factors from animal tissues.

Main Methods:

  • Analysis of soluble factors from invasive and non-invasive strains of Staphylococcus and Streptococcus.
  • Assays to measure tissue permeability changes in the presence of bacterial factors.
  • Evaluation of the impact of the bacterial factor on infections caused by other bacteria and vaccine viruses.
  • Comparison of the bacterial factor's effects with those of animal-derived spreading factors.

Main Results:

  • Invasive strains of Staphylococcus and Streptococcus secrete a soluble factor that significantly increases tissue permeability.
  • This factor enhances infections caused by the producing organisms, other bacteria, and vaccine viruses.
  • Non-invasive strains of these bacteria lack this enhancing factor.
  • The bacterial factor appears to enter the bloodstream, potentially increasing susceptibility to infection systemically.
  • The observed effects are similar to those elicited by spreading factors found in animal tissues, particularly from testicles.

Conclusions:

  • A soluble factor produced by invasive Staphylococcus and Streptococcus contributes to increased tissue permeability and enhanced infection severity.
  • This factor plays a role in the broader pathogenesis of bacterial infections, potentially affecting multiple sites.
  • The similarity to animal spreading factors suggests a conserved biological mechanism for tissue permeabilization.

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