title: Immunohistochemical analysis of FoxP3+ cells in periapical granulomas and radicular cysts.
abstract: OBJECTIVE
  To compare the number of FoxP3(+) cells between periapical granulomas (PGs) and radicular cysts (RCs), and to correlate this number with the intensity of the inflammatory infiltrate in these lesions and with epithelial thickness of RCs.
  
  
  METHODS
  Thirty PGs and 30 RCs were submitted to immunohistochemical analysis using an anti-FoxP3 polyclonal antibody. FoxP3(+) cells were counted under a light microscope (×400 magnification) in five fields and the mean value was calculated for each specimen. Statistical tests were used to evaluate differences in the number of FoxP3(+) cells according to type of lesion (PG vs. RC), intensity of the inflammatory infiltrate (grade I/II vs. grade III), and epithelial thickness of RCs (atrophic vs. hyperplastic).
  
  
  RESULTS
  FoxP3(+) cells were detected in most PGs (93.3%) and RCs (93.3%). The median number of FoxP3(+) cells was 2.40 in PGs and 1.00 in RCs, with this difference being statistically significant (P=0.005). No significant differences in the number of FoxP3(+) cells were observed in terms of the intensity of the inflammatory infiltrate (P=0.465) or epithelial thickness of RCs (P=0.737).
  
  
  CONCLUSIONS
  The present results suggest a greater participation of regulatory T cells in the modulation of the inflammatory response in PGs. In addition, the presence of a less effective regulatory environment in RCs, together with the high levels of inflammatory mediators as reported in the literature, may contribute to the greater growth potential of these lesions.
authors.affiliation: Federal University of Rio Grande do Norte, Natal, RN, Brazil.
authors.forename: Raniel Fernandes
authors.initials: RF
authors.lastname: Peixoto
authors.forename: Joabe dos Santos
authors.initials: Jdos S
authors.lastname: Pereira
authors.forename: Cassiano Francisco Weege
authors.initials: CF
authors.lastname: Nonaka
authors.forename: Ericka Janine Dantas da
authors.initials: EJ
authors.lastname: Silveira
authors.forename: Márcia Cristina da Costa
authors.initials: MC
authors.lastname: Miguel
mesh_terms: D001284:Atrophy; D002452:Cell Count; D004848:Epithelium / Q000473:pathology; D051858:Forkhead Transcription Factors / Q000032:analysis*; D006801:Humans; D006965:Hyperplasia; D007150:Immunohistochemistry; D007249:Inflammation / Q000473:pathology; D018836:Inflammation Mediators / Q000032:analysis; D010484:Periapical Granuloma / Q000473:pathology*; D011842:Radicular Cyst / Q000473:pathology*; D050378:T-Lymphocytes, Regulatory / Q000473:pathology
chemical_list: C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D018836:Inflammation Mediators