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Filifactor alocis Pathogenicity Requires TLR2 and the Oral Microbiome.
A Vashishta1, L Li2, S Srivastava3
1Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, USA.
Journal of Dental Research
|May 12, 2025
Summary
Filifactor alocis promotes periodontitis by causing bone loss and inflammation. Its pathogenicity requires a normal oral microbiome and Toll-like receptor 2 (TLR2).
Area of Science:
- Microbiology
- Immunology
- Periodontology
Background:
- Filifactor alocis enrichment is linked to periodontitis progression.
- The direct pathogenic role of F. alocis in dysbiotic oral microbial communities is unclear.
Purpose of the Study:
- To investigate the pathogenic potential of F. alocis in experimental periodontitis.
- To elucidate the mechanisms underlying F. alocis-induced inflammation and bone loss.
Main Methods:
- Oral gavage model of experimental periodontitis in mice.
- Assessment of alveolar bone loss, proinflammatory markers, and microbial community shifts.
- Evaluation in germ-free and Toll-like receptor 2 (TLR2)-deficient mice.
Main Results:
- F. alocis infection promoted alveolar bone loss and overexpression of inflammatory markers.
- F. alocis disrupted the homeostatic oral microbiome, inducing a dysbiotic state.
- Systemic inflammation and antibody responses against F. alocis were observed.
- Alveolar bone loss was absent in germ-free or TLR2-deficient mice infected with F. alocis.
Conclusions:
- F. alocis acts as an oral pathogen, driving inflammation and bone resorption in periodontitis.
- The commensal oral microbiome and TLR2 are essential for F. alocis pathogenicity.
- F. alocis disrupts host-microbiome homeostasis, contributing to periodontitis pathogenesis.
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