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STUDIES ON THE PATHOGENESIS OF STAPHYLOCOCCAL INFECTION : I. THE EFFECT OF REPEATED SKIN INFECTIONS
J E Johnson1, L E Cluff, K Goshi
1Division of Allergy and Infectious Disease, Department of Medicine, The Johns Hopkins University School of Medicine and Hospital, Baltimore.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Repeated staphylococcal infections in rabbits induced delayed hypersensitivity, increasing skin and joint infection severity. This hypersensitivity enhanced bacterial infectivity without detectable serum antibodies, impacting staphylococcal disease progression.
Area of Science:
- Immunology
- Microbiology
- Dermatology
Background:
- Staphylococcal infections are a significant health concern.
- Understanding host responses to repeated bacterial infections is crucial for developing effective treatments.
- The role of hypersensitivity in bacterial pathogenesis requires further investigation.
Purpose of the Study:
- To investigate the impact of repeated staphylococcal infections on experimentally induced lesions in rabbit skin.
- To determine the relationship between delayed hypersensitivity and serum antibody production in staphylococcal infections.
- To explore the influence of hypersensitivity on the severity and infectivity of Staphylococcus aureus.
Main Methods:
- Repeated inoculation of rabbit skin with Staphylococcus aureus.
- Induction of delayed hypersensitivity using washed heat-killed staphylococci.
- Assessment of lesion characteristics, bacterial infectivity, and pyoarthrosis severity.
- Evaluation of susceptibility to anterior chamber eye infections.
Main Results:
- Repeated staphylococcal infection led to delayed hypersensitivity without significant serum antibody response.
- Delayed hypersensitivity increased Staphylococcus aureus infectivity and lesion severity in skin and joints.
- Vaccination-induced delayed hypersensitivity mimicked these effects.
- Sensitized rabbits showed decreased susceptibility to severe anterior chamber eye infections.
Conclusions:
- Delayed hypersensitivity plays a critical role in exacerbating staphylococcal skin and joint infections.
- Hypersensitivity can enhance bacterial infectivity independently of humoral immunity.
- Non-specific inflammation may contribute to staphylococcal pathogenesis, similar to specific hypersensitivity.
- Further research is needed to fully elucidate the interplay between immunity, hypersensitivity, and staphylococcal infection.
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