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A Mouse Model to Assess Innate Immune Response to Staphylococcus aureus Infection
09:15

A Mouse Model to Assess Innate Immune Response to Staphylococcus aureus Infection

Published on: February 28, 2019

ABSCESS-FORMING FACTOR(S) PRODUCED BY STAPHYLOCOCCUS AUREUS. II. ABSCESS FORMATION AND IMMUNITY BY A STAPHYLOCOCCUS

G T LAM, F J SWEENEY, C M WITMER

    Journal of Bacteriology
    |July 1, 1963
    PubMed

    Insights

    Staphylococcus aureus mutants were studied for abscess formation. Coagulase-positive strains, including mutants, formed abscesses, but only the parent strain induced local immunity.

    Area of Science:

    • Microbiology
    • Immunology
    • Bacteriology

    Background:

    • Staphylococcus aureus is a significant pathogen.
    • Understanding its virulence factors, such as coagulase and hemolysin, is crucial for developing effective treatments.
    • Previous research indicated the role of extracellular products in staphylococcal infections.

    Purpose of the Study:

    • To investigate the role of coagulase and hemolysin in abscess formation by Staphylococcus aureus.
    • To compare the pathogenicity and immunogenicity of a parent strain and its mutants.
    • To explore the development of local immunity against Staphylococcus aureus.

    Main Methods:

    • Derivation of three Staphylococcus aureus mutants with varying virulence factors (coagulase, hemolysin) using ultraviolet irradiation.
    • Characterization of strains using bacteriophage typing, mannitol utilization, and antibiotic sensitivity tests.
    • Assessment of pathogenicity and immunogenicity in Swiss albino and inbred mice via subcutaneous injections.

    Main Results:

    • All four strains (parent and three mutants) were capable of inducing abscesses in mice.
    • Abscess formation was observed in strains possessing coagulase, regardless of hemolysin activity.
    • Local immunity was only achieved with the virulent parent strain, suggesting a complex immune response.

    Conclusions:

    • Coagulase appears to be a key factor in the ability of Staphylococcus aureus to cause abscesses.
    • Hemolysin alone does not induce abscess formation.
    • The development of local immunity involves factors beyond just coagulase and hemolysin.
    Keywords:
    ABSCESSEXPERIMENTAL LAB STUDYHEMOLYSINSHYDROLASESIMMUNITYMICESTAPHYLOCOCCAL INFECTIONSULTRAVIOLET RAYS

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