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Neisserial Opa proteins: impact on colonization, dissemination and immunity
1Department of Medical Genetics and Microbiology, University of Toronto, Toronto, Ontario, Canada. scott.gray.owen@utoronto.ca
Scandinavian Journal of Infectious Diseases
|November 19, 2003
Summary
Pathogenic Neisseria species use Opa proteins for cell attachment and invasion. These proteins mediate interactions with host cells, influencing infection stages and immune responses.
Area of Science:
- Microbiology
- Immunology
- Cell Biology
Background:
- Pathogenic Neisseria species utilize Opa proteins, which are phase-variable and antigenically distinct.
- Opa proteins facilitate bacterial attachment to diverse host cell types.
Purpose of the Study:
- To review recent advances in understanding Opa protein-mediated interactions.
- To discuss the impact of these interactions on host cellular responses during Neisseria infection.
Main Methods:
- Review of existing literature on Neisseria Opa proteins and host cell interactions.
- Analysis of studies investigating Opa variants binding to specific host receptors (syndecans, fibronectin, vitronectin, CEACAMs).
Main Results:
- Opa variants bind to heparan sulfate proteoglycans (syndecans) and extracellular matrix proteins (fibronectin, vitronectin).
- Other Opa variants interact with carcinoembryonic antigen (CEA) family adhesion molecules.
- These interactions facilitate bacterial entry, transcytosis, endothelial cell invasion, lymphocyte suppression, and neutrophil interactions.
Conclusions:
- Opa protein-mediated interactions are crucial for Neisseria pathogenesis.
- Understanding these interactions provides insights into host-pathogen dynamics and potential therapeutic targets.
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