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Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells
09:25

Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells

Published on: August 19, 2016

HOST-PARASITE RELATIONSHIPS AMONG GROUP A STREPTOCOCCI. 3. DEPRESSION OF RETICULOENDOTHELIAL FUNCTION BY

E E HANNA, D W WATSON

    Journal of Bacteriology
    |January 1, 1965
    PubMed

    Insights

    Group A streptococci pyrogenic exotoxins prolonged depress reticuloendothelial system (RES) function in rabbits. This depression may enhance the harmful effects of other toxins, increasing lethality and tissue damage.

    Area of Science:

    • Microbiology
    • Immunology
    • Toxicology

    Background:

    • Host-parasite interactions are crucial in understanding bacterial pathogenesis.
    • Group A streptococci produce pyrogenic exotoxins with significant biological activity.
    • The reticuloendothelial system (RES) plays a vital role in host defense.

    Purpose of the Study:

    • To investigate the effect of streptococcal pyrogenic exotoxins on reticuloendothelial system (RES) function.
    • To compare the RES-modulating effects of streptococcal exotoxins with bacterial endotoxins.

    Main Methods:

    • Experimental animals (rabbits) were treated with streptococcal pyrogenic exotoxins.
    • Reticuloendothelial system (RES) function was assessed by measuring the clearance rate of colloidal carbon from circulating blood.
    • Comparisons were made with animals treated with Escherichia coli endotoxin.

    Main Results:

    • Intravenous injection of streptococcal pyrogenic exotoxin caused a prolonged depression of RES function (at least 24 hours).
    • Repeated toxin administration did not lead to stimulation but abolished the initial depression.
    • Escherichia coli endotoxin caused initial RES depression followed by stimulation within 24-48 hours.

    Conclusions:

    • Streptococcal pyrogenic exotoxins significantly and persistently impair RES function.
    • This prolonged RES depression is a potential mechanism for potentiating the toxicity of other agents like streptolysin O and gram-negative endotoxins.
    • Understanding these host-parasite interactions is key to addressing streptococcal infections.
    Keywords:
    BLOOD CIRCULATIONENDOTOXINSESCHERICHIA COLIEXPERIMENTAL LAB STUDYPARASITESPYROGENSRABBITSRETICULOENDOTHELIAL SYSTEMSTREPTOCOCCUS PYOGENESSTREPTOLYSINTOXICOLOGIC REPORTTOXINS AND ANTITOXINS

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