title: A controversial role for IL-12 in immune response and bone resorption at apical periodontal sites.
abstract: Periapical lesions are inflammatory conditions of tooth periapical tissues, triggered by dental pulp infection and characterized by exudation of immune cells to the affected tissues and production of inflammatory mediators such as cytokines. The inflammatory periapical reaction is mainly driven by Th1, Th2, and Th17 responses, and such polarization may modulate progression of the disease and expression of bone proresorptive cytokines. IL-12 is a potent inducer of IFN-γ production, which stimulates Th1 effector cells. Many evidences have shown a positive correlation between the bone resorptive cytokine IL-1β and the production of IL-12 and IFN-γ. Furthermore, IL-12 may have a potential role in the release of bone resorptive mediators and blockade of Th2 cytokines, affecting the progression of periapical bone loss. Nevertheless, IL-12 and IFN-γ have also been described as suppressors of osteoclast differentiation and activation, favoring bone maintenance. This paper focuses on the controversial roles of IL-12 in periapical lesions.
authors.affiliation: Department of Oral Surgery and Pathology, School of Dentistry, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Celso Martins
authors.initials: CM
authors.lastname: Queiroz-Junior
authors.forename: Marcelo José Barbosa
authors.initials: MJ
authors.lastname: Silva
authors.forename: Jôice Dias
authors.initials: JD
authors.lastname: Corrêa
authors.forename: Mila Fernandes Moreira
authors.initials: MF
authors.lastname: Madeira
authors.forename: Thiago Pompermaier
authors.initials: TP
authors.lastname: Garlet
authors.forename: Gustavo Pompermaier
authors.initials: GP
authors.lastname: Garlet
authors.forename: Fernando Queiroz
authors.initials: FQ
authors.lastname: Cunha
authors.forename: Mauro Martins
authors.initials: MM
authors.lastname: Teixeira
authors.forename: Tarcília Aparecida
authors.initials: TA
authors.lastname: da Silva
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D001862:Bone Resorption / Q000276:immunology*; D006801:Humans; D018664:Interleukin-12 / Q000276:immunology* / Q000494:pharmacology; D010486:Periapical Tissue / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D018664:Interleukin-12