Porphyromonas gingivalis Outer Membrane Vesicles Increase Vascular Permeability

Area of Science:

• Microbiology
• Vascular Biology
• Infectious Diseases

Background:

• Periodontitis, a gum disease, is linked to systemic conditions like cardiovascular disease.
• Porphyromonas gingivalis is a key bacterium in periodontitis, with its presence in circulation associated with vascular problems.
• The role of P. gingivalis outer membrane vesicles (OMVs) in vascular interactions remains unclear.

Purpose of the Study:

• To investigate the effects of P. gingivalis OMVs on endothelial cells and vascular integrity.
• To determine the role of gingipains, specific enzymes from P. gingivalis, in OMV-mediated vascular effects.

Main Methods:

• Isolation of OMVs from wild-type and gingipain-deficient P. gingivalis strains.
• Assessment of endothelial cell permeability using dextran assays.
• Evaluation of vascular disease in a zebrafish larvae model.
• Analysis of PECAM-1 (CD31) expression on human microvascular endothelial cells via flow cytometry.

Main Results:

• P. gingivalis OMVs significantly increased endothelial cell permeability and vascular disease in zebrafish.
• Gingipain-deficient OMVs showed reduced effects on vascular permeability and disease.
• OMVs decreased PECAM-1 (CD31) levels on endothelial cells in a gingipain-dependent manner.

Conclusions:

• P. gingivalis OMVs promote vascular permeability and contribute to systemic disease.
• Gingipains on the OMV surface are crucial mediators of these vascular effects, likely through proteolytic cleavage of adhesion molecules like PECAM-1.
• This study highlights the role of bacterial OMVs in mediating systemic diseases associated with periodontitis.