Commensal Communism and the Oral Cavity

Henderson, B.; Wilson, M.
September 1998
Journal of Dental Research;Sep1998, Vol. 77 Issue 9, p1674
Academic Journal
The world we live in contains unimaginable numbers of bacteria, and these and other single-celled creatures represent the major diversity of life on our planet. During the last decade or so, the complexity and intimacy of the interactions which occur between bacteria and host eukaryotic cells during the process of infection have begun to emerge. The study of such interactions is the subject of the new discipline of cellular microbiology. This intimacy of bacteria/host interactions creates a major paradox. The average human being is 90% bacteria in terms of cell numbers. These bacteria constitute the commensal or normal microflora and populate the mucosal surfaces of the oral cavity, gastrointestinal tract, urogenital tract, and the surface of the skin. In bacterial infections, much of the pathology is due to the release of a range of bacterial components (e.g., modulins such as lipopolysaccharide, peptidoglycan, DNA, molecular chaperones), which induce the synthesis of the local hormone-like molecules known as pro-inflammatory cytokines. However, such components must also be constantly released by the vast numbers of bacteria constituting the normal microflora and, as a consequence, our mucosae should constantly be in a state of inflammation. This is patently not the case, and a hypothesis is forwarded to account for this "commensal paradox", namely, that our commensal bacteria and mucosal surfaces exist in a state of bio-communism, forming a unified "tissue" in which interactions between bacteria and epithelia are finely balanced to ensure bacterial survival and prevent the induction of damaging inflammation. Evidence is emerging that bacteria can produce a variety of proteins which can inhibit the synthesis/release of inflammatory cytokines. The authors predict that such proteins are simply one part of an extensive signaling system which occurs between bacteria and epithelial cells at mucosal surfaces such as those found in the oral cavity.


Related Articles

  • Interleukin-1 as a genetic marker for periodontitis: Review of the literature. Grigoriadou, Marianna E.; Koutayas, Spiridon-Oumvertos; Madianos, Phoebus N.; Strub, Jorg-Rudolf // Quintessence International;2010, Vol. 41 Issue 6, p517 

    Periodontitis is considered to be a multifactorial disease. Studies have indicated that part of the clinical variability in periodontitis may be explained by genetic factors. Genes can affect the immunoinflammatory host response to bacterial challenge in the periodontal tissues by means of an...

  • Heterogeneity of Surfaces of Subgingival Bacteria as Detected by Zeta Potential Measurements. COWAN, M. M.; VAN DER MEI, H. C.; STOKROOS, I.; BUSSCHER, H. J. // Journal of Dental Research;Nov1992, Vol. 71 Issue 11, p1803 

    Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans (A.a.) are Gram-negative bacteria which are implicated in various forms of periodontal disease. The Gram-positive Peptostreptococcus micros may also play an important role. For investigation of the possible...

  • Evaluation of nonsurgical periodontal therapy in chronic periodontitis patients with anemia by estimating hematological parameters and high-sensitivity C-reactive protein levels. Musalaiah, S. V. V. S.; Anupama, M.; Nagasree, M.; Krishna, Ch. Murali; Kumar, Aravind; Kumar, P. Mohan // Journal of Pharmacy & Bioallied Sciences;Jul2014 Dental Supplement, Vol. 6 Issue S1, pS64 

    Background: Periodontal tissues mount an immune inflammatory response to bacteria and their products. Certain inflammatory cytokines produced during periodontal inflammation increase the production of acute phase proteins like high-sensitivity C-reactive protein (hs-CRP) and can depress...

  • Porphyromonas gingivalis-Epithelial Cell Interactions in Periodontitis. Andrian, E.; Grenier, D.; Rouabhia, M. // Journal of Dental Research;May2006, Vol. 85 Issue 5, p392 

    Emerging data on the consequences of the interactions between invasive oral bacteria and host cells have provided new insights into the pathogenesis of periodontal disease. Indeed, modulation of the mucosal epithelial barrier by pathogenic bacteria appears to be a critical step in the initiation...

  • Toll-like Receptors, NOD1, and NOD2 in Oral Epithelial Cells. Sugawara, Y.; Uehara, A.; Fujimoto, Y.; Kusumoto, S.; Fukase, K.; Shibata, K.; Sugawara, S.; Sasano, T.; Takada, H. // Journal of Dental Research;Jun2006, Vol. 85 Issue 6, p524 

    Oral epithelium might be the first barrier against oral bacteria in periodontal tissue. We hypothesized that oral epithelium is endowed with innate immune receptors for bacterial components, which play roles in host defense against bacterial infection without being accompanied by excessive...

  • Subgingival and Tongue Microbiota during Early Periodontitis. Tanner, A. C. R.; Paster, B. J.; Lu, S. C.; Kanasi, E.; Kent, Jr., R.; Van Dyke, T.; Sonis, S. T. // Journal of Dental Research;Apr2006, Vol. 85 Issue 4, p318 

    Periodontal infections have a microbial etiology. Association of species with early disease would be useful in determining which microbes initiate periodontitis. We hypothesized that the microbiota of subgingival and tongue samples would differ between early periodontitis and health. A...

  • Periodontitis - the new caries? Hughes, Francis // British Dental Journal;10/24/2014, Vol. 217 Issue 8, p387 

    An introduction is presented in which the editor discusses various reports within the issue on topics including periodontal diseases and medicine, relationship between periodontitis and systemic health, and prevalence of periodontitis in a Roman-Britain population

  • The Localization of Periodontal-Disease-Associated Bacteria in Human Periodontal Pockets. Noiri, Y.; Li, L.; Ebisu, S. // Journal of Dental Research;Oct2001, Vol. 80 Issue 10, p1930 

    Some Gram-negative anaerobes are associated with the incidence and progression of periodontal disease. In periodontal pockets, however, the localization of those bacteria is unknown. We investigated the localization of 5 bacterial species in human periodontal pockets. Fifteen teeth with a part...

  • Rheumatoid arthritis is linked to oral bacteria: etiological association. Ogrendik, Mesut // Modern Rheumatology (Springer Science & Business Media B.V.);Oct2009, Vol. 19 Issue 5, p453 

    The purpose of this review is to evaluate the association between rheumatoid arthritis (RA) and periodontopathic bacteria. Clinical studies of RA and periodontal disease have provided evidence for a significant association between the two disorders. Patients with long-standing active RA have a...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics