Mechanisms of Porphyromonas gingivalis to translocate over the oral mucosa and other tissue barriers

ABSTRACT

Introduction

The oral pathogen Porphyromonas gingivalis is not only associated with periodontitis but also with systemic diseases elsewhere in the body. The mechanisms by which P. gingivalis travels from the oral cavity to other organs in the body are largely unknown. This review describes the four putative mechanisms supported by experimental evidence, which enable translocation of P. gingivalis over the oral mucosa, endothelial barriers and subsequent dissemination into the bloodstream.

Mechanisms

The first mechanism: proteolytic enzymes secreted by P. gingivalis degrade adhesion molecules between tissue cells, and the extracellular matrix. This weakens the structural integrity of the mucosa and allows P. gingivalis to penetrate the tissue. The second is transcytosis: bacteria actively enter tissue cells and transfer to the next layer or the extracellular space. By travelling from cell to cell, P. gingivalis reaches deeper structures. Thirdly, professional phagocytes take up P. gingivalis and travel to the bloodstream where P. gingivalis is released. Lastly, P. gingivalis can adhere to the hyphae forming Candida albicans. These hyphae can penetrate the mucosal tissue, which may allow P. gingivalis to reach deeper structures.

Conclusion

More research could elucidate targets to inhibit P. gingivalis dissemination and prevent the onset of various systemic diseases.

KEYWORDS:

• Porphyromonas gingivalis
• oral mucosa
• translocation
• blood dissemination
• periodontitis

Acknowledgments

Parts of the image in Figures 1, 2 , 3 , 4 and 5 were drawn by using pictures from Servier Medical Art. Servier Medical Art by Servier is licensed under a Creative Commons Attribution 3.0 Unported License.

Disclosure statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Author contributions

CdJ, BK, TdV, FB and SG conceived the plan for the manuscript. CdJ wrote the initial draft of the manuscript. BK, TdV, FB and SG critically commented and suggested revisions on all versions of the manuscript.

Additional information

Funding

This project is funded by the faculty of Dentistry, Academic Centre for Dentistry in Amsterdam, University of Amsterdam and Free University of Amsterdam.