title: Distinct Th1, Th2 and Treg cytokines balance in chronic periapical granulomas and radicular cysts.
abstract: BACKGROUND
  Periapical lesions are a host response that involves immune reaction to prevent dissemination of bacteria from an infected root canal. The purpose of this study was to evaluate the levels of nitric oxide (NO), IL-4, TGF-beta, tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) in chronic periapical lesions and to determine their possible association with clinical and radiographic parameters.
  
  
  METHODS
  Seventeen human radicular cysts and 30 periapical granulomas were used in this study. Cytokines and NO were assessed by enzyme-linked immunosorbent assay and by the Griess reaction respectively confirmed by immunohistochemical.
  
  
  RESULTS
  TNF-alpha and IFN-gamma were detected in 10% of granulomas and in 41.2% and 70% of radicular cysts. IL-4 was reactive in 24% of cysts, and TGF-beta was positive in all samples. Patients with tenderness showed significantly higher levels of IFN-gamma and IL-4 (P < 0.05). Swelling was associated with high levels of TNF-alpha, IFN-gamma, and IL-4 (P < 0.05). Lesions presenting bone resorption were associated with high levels of NO (P < 0.05).
  
  
  CONCLUSIONS
  Periapical granulomas display a regulatory environment characterized by high TGF-beta and low inflammatory cytokine levels, while radicular cysts has mist Th1 and Th2 inflammatory reaction with the presence of IFN-gamma, TNF-alpha, and IL-4.
authors.affiliation: Laboratory of Immunology, Federal University of 'Triângulo Mineiro'- UFTM, Uberaba.
authors.forename: Tatiana Beber
authors.initials: TB
authors.lastname: Teixeira-Salum
authors.forename: Denise Bertulucci Rocha
authors.initials: DB
authors.lastname: Rodrigues
authors.forename: Aurélia M
authors.initials: AM
authors.lastname: Gervásio
authors.forename: Cássio J A
authors.initials: CJ
authors.lastname: Souza
authors.forename: Virmondes
authors.initials: V
authors.lastname: Rodrigues
authors.forename: Adriano Motta
authors.initials: AM
authors.lastname: Loyola
mesh_terms: D001862:Bone Resorption / Q000000981:diagnostic imaging / Q000276:immunology; D002908:Chronic Disease; D016207:Cytokines / Q000276:immunology*; D004487:Edema / Q000276:immunology; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000032:analysis; D015847:Interleukin-4 / Q000032:analysis; D008297:Male; D009569:Nitric Oxide / Q000032:analysis; D010146:Pain / Q000276:immunology; D010484:Periapical Granuloma / Q000000981:diagnostic imaging / Q000276:immunology* / Q000473:pathology; D011842:Radicular Cyst / Q000000981:diagnostic imaging / Q000276:immunology* / Q000473:pathology; D011859:Radiography; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000032:analysis; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
chemical_list: D016207:Cytokines; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4; D009569:Nitric Oxide; D007371:Interferon-gamma