Related Experiment Video
Updated: Nov 11, 2025
A Mouse Model to Assess Innate Immune Response to Staphylococcus aureus Infection
Published on: February 28, 2019
Staphylococcus aureus lipoproteins promote abscess formation in mice, shielding bacteria from immune killing
Majd Mohammad1, Manli Na2, Zhicheng Hu2,3
1Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. majd.mohammad@rheuma.gu.se.
Abstract:
Despite being a major bacterial factor in alerting the human immune system, the role of Staphylococcus aureus (S. aureus) lipoproteins (Lpp) in skin infections remains largely unknown. Here, we demonstrated that subcutaneous injection of S. aureus Lpp led to infiltration of neutrophils and monocytes/macrophages and induced skin lesions in mice. Lipid-moiety of S. aureus Lpp and host TLR2 was responsible for such effect. Lpp-deficient S. aureus strains exhibited smaller lesion size and reduced bacterial loads than their parental strains; the altered phenotype in bacterial loads was TLR2-independent. Lpp expression in skin infections contributed to imbalanced local hemostasis toward hypercoagulable state. Depletion of leukocytes or fibrinogen abrogated the effects induced by Lpp in terms of skin lesions and bacterial burden. Our data suggest that S. aureus Lpp induce skin inflammation and promote abscess formation that protects bacteria from innate immune killing. This suggests an intriguing bacterial immune evasion mechanism.
Insights
Staphylococcus aureus lipoproteins (Lpp) cause skin lesions and inflammation by recruiting immune cells. These lipoproteins promote bacterial survival in skin infections, suggesting an immune evasion strategy.
Area of Science:
- Microbiology
- Immunology
- Dermatology
Background:
- Staphylococcus aureus lipoproteins (Lpp) are key immune activators, but their role in skin infections is unclear.
- Understanding Lpp's function is crucial for addressing S. aureus skin infections.
Purpose of the Study:
- To investigate the role of Staphylococcus aureus lipoproteins (Lpp) in the pathogenesis of skin infections.
- To elucidate the mechanisms by which Lpp contribute to S. aureus skin infections.
Main Methods:
- Subcutaneous injection of S. aureus Lpp in mouse models.
- Assessment of immune cell infiltration, lesion development, and bacterial load.
- Evaluation of the roles of Lpp lipid moiety and host TLR2.
- Analysis of hemostasis and the impact of leukocyte and fibrinogen depletion.
Main Results:
- S. aureus Lpp induced skin lesions, neutrophil, and monocyte/macrophage infiltration, dependent on Lpp lipid moiety and host TLR2.
- Lpp-deficient S. aureus strains showed reduced lesion size and bacterial loads, independent of TLR2.
- Lpp expression promoted a hypercoagulable state in skin infections.
- Leukocyte or fibrinogen depletion abrogated Lpp-induced skin lesions and bacterial burden.
Conclusions:
- Staphylococcus aureus Lpp drive skin inflammation and abscess formation, aiding bacterial survival against innate immunity.
- Lpp represent a significant bacterial immune evasion mechanism in skin infections.
- Targeting Lpp could be a therapeutic strategy for S. aureus skin infections.
More Related Videos
Related Concept Videos
01:31Defense Against Bacterial Pathogens
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
01:19Formation of Lipopolysaccharides