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09:11
Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination
Published on: September 25, 2014
CONCERNING A POLYVALENT ANTIGEN FOR THE COMPLEMENT FIXATION TEST FOR STREPTOCOCCUS VIRIDANS INFECTION.
1Department of Clinical Pathology of Cornell University Medical College, and The Second Medical Division of Bellevue Hospital, New York.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Streptococcus viridans shows low virulence in animal models. Complement fixation tests for Streptococcus viridans infections are too complex for routine clinical use due to poor antigen quality and difficult methodology.
Area of Science:
- Microbiology
- Immunology
Background:
- Streptococcus viridans is a bacterium with generally low pathogenicity.
- Assessing immune responses to Streptococcus viridans can be challenging.
Purpose of the Study:
- To evaluate the virulence of Streptococcus viridans in animal models.
- To investigate the utility of complement fixation tests for diagnosing Streptococcus viridans infections.
Main Methods:
- Inoculation of white mice and rabbits with Streptococcus viridans.
- Preparation of antigens from Streptococcus viridans strains.
- Analysis of rabbit serum for complement-fixing antibodies.
Main Results:
- Streptococcus viridans demonstrated extremely low virulence in mice and rabbits.
- Rabbit serum showed poor complement-fixing activity against Streptococcus viridans.
- Antigens derived from Streptococcus viridans were found to be poor in fixable substances.
- The complement fixation test methodology proved laborious and difficult for clinical application.
Conclusions:
- Streptococcus viridans possesses minimal virulence in common laboratory animals.
- The complement fixation test is not practical for routine clinical diagnosis of Streptococcus viridans infections due to technical limitations and poor antigen performance.
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