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ANTIGENIC DIFFERENCES BETWEEN MATT HEMOLYTIC STREPTOCOCCI AND THEIR GLOSSY VARIANTS

R C Lancefield1, E W Todd

  • 1Hospital of The Rockefeller Institute for Medical Research.

The Journal of Experimental Medicine
|October 30, 2009
PubMed

Insights

The matt form of hemolytic streptococci induces type-specific antibodies and immunity in rabbits and mice, unlike the glossy form. Anti-matt sera protect against infection, while anti-glossy sera do not, highlighting the importance of the matt phenotype for vaccine development.

Area of Science:

  • Microbiology
  • Immunology
  • Bacteriology

Background:

  • Hemolytic streptococci exist in distinct colony forms, matt and glossy.
  • The immunogenic and protective properties of these different forms are not fully understood.

Purpose of the Study:

  • To investigate the immunogenicity of matt and glossy forms of hemolytic streptococci.
  • To determine the protective efficacy of antibodies generated against these forms.

Main Methods:

  • Rabbits were immunized with matt and glossy forms of hemolytic streptococci.
  • Precipitin and passive protection tests were performed.
  • Mice were vaccinated to assess active immunity.

Main Results:

  • Sera from rabbits immunized with matt organisms contained type-specific antibodies, unlike those immunized with glossy organisms.
  • Anti-matt sera conferred passive protection against virulent homologous strains in mice.
  • Vaccination with matt organisms induced active immunity in mice, whereas glossy organisms did not.

Conclusions:

  • The matt phenotype of hemolytic streptococci is crucial for eliciting type-specific antibodies and protective immunity.
  • Glossy forms are poorly immunogenic and do not induce protective immunity.
  • These findings have implications for understanding streptococcal virulence and developing effective vaccines.

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