title: Destructive and protective roles of cytokines in periodontitis: a re-appraisal from host defense and tissue destruction viewpoints.
abstract: Periodontal diseases (PD) are chronic infectious inflammatory diseases characterized by the destruction of tooth-supporting structures, being the presence of periodontopathogens required, but not sufficient, for disease development. As a general rule, host inflammatory mediators have been associated with tissue destruction, while anti-inflammatory mediators counteract and attenuate disease progression. With the discovery of several T-cell subsets bearing distinct immunoregulatory properties, this pro- vs. anti-inflammatory scenario became more complex, and a series of studies has hypothesized protective or destructive roles for Th1, Th2, Th17, and Treg subpopulations of polarized lymphocytes. Interestingly, the "protective vs. destructive" archetype is usually considered in a framework related to tissue destruction and disease progression. However, it is important to remember that periodontal diseases are infectious inflammatory conditions, and recent studies have demonstrated that cytokines (TNF-α and IFN-γ) considered harmful in the context of tissue destruction play important roles in the control of periodontal infection. Therefore, in this review, the state-of-the-art knowledge concerning the protective and destructive roles of host inflammatory immune response will be critically evaluated and discussed from the tissue destruction and control-of-infection viewpoints.
authors.affiliation: OSTEOimmunology Laboratory, Department of Biological Sciences, School of Dentistry of Bauru, São Paulo University, FOB/USP, Al. Octávio Pinheiro Brisola, 9-75 CEP 17012-901, Bauru, SP, Brazil. garletgp@usp.br
authors.forename: G P
authors.initials: GP
authors.lastname: Garlet
mesh_terms: D056704:Adaptive Immunity / Q000276:immunology; D016207:Cytokines / Q000276:immunology*; D018450:Disease Progression; D006801:Humans; D007113:Immunity, Innate / Q000276:immunology; D018836:Inflammation Mediators / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology; D010518:Periodontitis / Q000276:immunology* / Q000382:microbiology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma