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THE EFFECT OF INJECTIONS OF HEMOLYTIC STREPTOCOCCI ON SUSCEPTIBLE AND INSUSCEPTIBLE ANIMALS
1Department of Bacteriology of the College of Physicians and Surgeons of Columbia University, New York.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Streptococci are rapidly cleared from cat circulation, primarily to the lungs where they are killed. In rabbits, muscle colonization leads to septicemia, suggesting bacterial washout from tissues.
Area of Science:
- Microbiology
- Immunology
- Pathology
Background:
- Streptococcal infections pose significant public health challenges.
- Understanding host-pathogen interactions is crucial for developing effective treatments.
Purpose of the Study:
- To investigate the distribution and fate of streptococci in susceptible (rabbits) and insusceptible (cats) animal models.
- To elucidate the mechanisms underlying streptococcal clearance and potential for septicemia.
Main Methods:
- Intravenous injection of streptococci into cats and rabbits.
- Analysis of bacterial distribution in various organs (lung, liver, spleen, muscle, etc.) over time.
- Assessment of bacterial viability and host immune response.
Main Results:
- Cats rapidly cleared streptococci, with lung exhibiting highest bacterial load and rapid killing.
- Rabbits showed different distribution; muscle colonization led to bacterial multiplication and subsequent septicemia.
- Bactericidal activity in cat lung was cell-dependent, not extract-dependent.
- Attempts at rabbit immunization were unsuccessful, but some treatments altered bacterial distribution.
Conclusions:
- Host species significantly influences streptococcal distribution and outcome.
- Bacterial multiplication in muscle tissue is a key factor in rabbit septicemia.
- Cellular immunity in organs like the lung plays a vital role in bacterial clearance.
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