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Staphylococcus pseudintermedius Sbi paralogs inhibit complement and bind IgM, IgG Fc and Fab
Alaa H Sewid1,2, M Nabil Hassan2, A M Ammar2
1Department of Biomedical and Diagnostic Sciences, University of Tennessee, Knoxville, Tennessee, United States of America.
Plos One
|July 24, 2019
Summary
Staphylococcus pseudintermedius uses its Sbi protein to evade the canine immune system by binding immunoglobulins and complement. This study characterizes Sbi
Area of Science:
- Veterinary Microbiology
- Immunology
- Bacterial Pathogenesis
Background:
- Staphylococci are successful pathogens due to immune evasion mechanisms.
- Staphylococcus pseudintermedius causes pyoderma in dogs, but its evasion proteins are understudied.
- Staphylococcus aureus Sbi protein interferes with innate immunity.
Purpose of the Study:
- To characterize the immune evasion role of Staphylococcus pseudintermedius Sbi protein.
- To investigate Sbi's interaction with canine immune components.
Main Methods:
- Cloning of S. pseudintermedius Sbi paralogs.
- Assessing binding of immunoglobulins (IgG, IgM) and complement (C3).
- Measuring neutralization of complement activity.
Main Results:
- S. pseudintermedius Sbi binds IgG from various species and canine C3.
- The Sbi protein neutralizes complement activity.
- Sbi binds to canine IgM and B cells, indicating immune cell interaction.
Conclusions:
- S. pseudintermedius Sbi protein possesses immune evasion functions.
- Sbi likely contributes to S. pseudintermedius pathogenesis in dogs.
- Further research into Sbi is warranted for understanding canine pyoderma.
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