The Oral Microbial Consortium's Interaction with the Periodontal Innate Defense System

Abstract

The oral microbial consortium is the most characterized polymicrobial microbial community associated with the human host. Extensive sampling of both microbial and tissue samples has demonstrated that there is a strong association between the type of microbial community found in the gingival crevice and the status of innate host mediator expression. The strong clinical association between the microbial community and the innate host response in both clinically healthy and diseased tissue suggests that the oral consortium has a direct effect on periodontal tissue expression of innate defense mediators. A preliminary study in germ-free mice has demonstrated that the oral commensal consortium has direct effect on IL-1β expression, indicating that this microbial community may contribute to the strong protective status of healthy gingival tissue. Likewise, the lipopolysaccharide composition and invasion characteristics of Porphyromonas gingivalis, an oral bacterium strongly associated with periodontitis, suggest that it may be a keystone member of the oral microbial community and facilitate a destructive change in the protective gingival innate host status.

Gene Regulation, Two Component Regulatory Systems, and Adaptive Responses in Treponema Denticola

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Impact of Dental Plaque Biofilms in Periodontal Disease: Management and Future Therapy

“…Expression of mediators such as interleukin 8 (IL-8), intercellular adhesion molecule (ICAM), E-selectin and β defensin molecules 1, 2 and 3 are required to form this neutrophil defense wall [64][65][66]. E-selectin is required for neutrophil migration from the highly vascularized gingival tissue, IL-8 is a key neutrophil chemo-attractant produced by epithelial cells, and ICAM facilitates adhesion of neutrophils to the tissue allowing formation of this wall [67,68].…”

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