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Updated: Jun 19, 2026
09:11
Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination
Published on: September 25, 2014
SEROLOGICAL RELATIONSHIPS AMONG AND BETWEEN THE STREPTOCOCCI AND PNEUMOCOCCI
1Department of Internal Medicine of Washington University School of Medicine, St. Louis.
The Journal of Experimental Medicine
|October 30, 2009
Summary
This study identifies two distinct groups within non-hemolytic streptococci using complement fixation. These groups show specific relationships to hemolytic streptococci and pneumococci, suggesting protein or lipoid-protein fractions are key.
Area of Science:
- Microbiology
- Immunology
- Bacteriology
Background:
- Non-hemolytic streptococci represent a diverse group of bacteria.
- Understanding their antigenic relationships is crucial for classification and immunological studies.
Purpose of the Study:
- To investigate the antigenic relationships among streptococci and pneumococci.
- To identify distinct serological groups within the non-hemolytic streptococcus family.
Main Methods:
- Utilized the complement fixation reaction as the primary serological assay.
- Employed whole bacterial solutions as antigens for testing.
Main Results:
- Confirmed the existence of two major groups within non-hemolytic streptococci.
- Demonstrated orderly serological relationships between one group and hemolytic streptococci.
- Showed relationships between the second group and the pneumococcus family.
- Identified cross-reactivity between hemolytic streptococci, non-hemolytic streptococci (right side), and pneumococci.
Conclusions:
- The observed cross-relationships are not attributed to precipitable substances.
- Tentatively proposed that protein or lipoid-protein fractions of bacterial cells mediate these antigenic relationships.
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