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Updated: Aug 10, 2026

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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
Published on: February 9, 2011
[The immunosuppressive activity of Streptococcus aureus peptidoglycan]
Summary
Peptidoglycan from Staphylococcus aureus suppresses delayed hypersensitivity (DH) in mice. This immunosuppressive effect is primarily associated with the insoluble fraction of peptidoglycan.
Area of Science:
- Immunology
- Microbiology
Background:
- Delayed hypersensitivity (DH) is a critical immune response.
- Staphylococcus aureus peptidoglycan (PG) is a major cell wall component with known immunomodulatory effects.
Purpose of the Study:
- To investigate the immunosuppressive activity of Staphylococcus aureus peptidoglycan (PG) on delayed hypersensitivity (DH) in a mouse model.
- To determine which fraction of PG is responsible for the observed immunosuppressive effects.
Main Methods:
- Mouse experiments utilizing a model of delayed hypersensitivity (DH) to guinea pig antigens.
- Fractionation of peptidoglycan into soluble and insoluble components.
- Immunosorbent assays to assess serological similarity.
Main Results:
- Peptidoglycan (PG) significantly suppressed delayed hypersensitivity (DH) in the experimental model.
- The immunosuppressive activity was localized to the insoluble fraction of PG.
- The soluble fraction of PG did not exhibit immunosuppressive properties.
- Immunosorbent experiments revealed serological similarity between the active factors in both soluble and insoluble PG fractions.
Conclusions:
- The insoluble fraction of Staphylococcus aureus peptidoglycan is responsible for suppressing delayed hypersensitivity.
- Despite differing solubility, the active immunosuppressive components in both PG fractions share serological similarities.
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