title: Increased number of regulatory T cells in children with eosinophilic esophagitis.
abstract: OBJECTIVE
  There are limited data on the role of regulatory T cells (Treg) in the disease pathology of eosinophilic esophagitis (EoE). We tested the differences in Treg in subjects with EoE compared with those with gastroesophageal reflux disease (GERD) and healthy controls (HC).
  
  
  METHODS
  Pediatric patients evaluated by endoscopy were recruited for our study. Participants were categorized into 3 groups: EoE, GERD, and HC. RNA purified from esophageal biopsies were used for real-time quantitative polymerase chain reaction assays and tested for forkhead box P3 (FoxP3) mRNA expression. Treg were identified as CD4+CD25hiCD127lo cells in peripheral blood and as CD3+/FoxP3+cells in esophageal tissue.
  
  
  RESULTS
  Forty-eight subjects were analyzed by real-time quantitative polymerase chain reaction: EoE (n = 33), GERD (n = 7), and HC (n = 8). FoxP3 expression was higher by up to 1.5-fold in the EoE group compared with the GERD and HC groups (P < 0.05). Protein levels of FoxP3 in blood and tissue were then investigated in 21 subjects: EoE (n = 10), GERD (n = 6), and HC (n = 5). The percentage of Treg and their subsets in peripheral blood were not significant between groups (P > 0.05). The amount of Treg in esophageal tissue was significantly greater in the EoE group (mean 10.7 CD3+/FoxP3+cells/high power field [HPF]) compared with the other groups (GERD, mean 1.7 CD3+/FoxP3+cells/HPF and HC, mean 1.6 CD3+/FoxP3+cells/HPF) (P < 0.05).
  
  
  CONCLUSIONS
  We show that Treg are increased in esophageal tissue of EoE subjects compared with GERD and HC subjects. The present study illustrates another possible mechanism involved in EoE that implicates impairment of immune homeostasis.
authors.affiliation: Department of Pediatrics, Lucile Packard Children's Hospital, Stanford University Medical Center, Palo Alto, CA, USA. judy.fuentebella@gmail.com
authors.forename: Judy
authors.initials: J
authors.lastname: Fuentebella
authors.forename: Anup
authors.initials: A
authors.lastname: Patel
authors.forename: Tammie
authors.initials: T
authors.lastname: Nguyen
authors.forename: Bharati
authors.initials: B
authors.lastname: Sanjanwala
authors.forename: William
authors.initials: W
authors.lastname: Berquist
authors.forename: John A
authors.initials: JA
authors.lastname: Kerner
authors.forename: Dorsey
authors.initials: D
authors.lastname: Bass
authors.forename: Kenneth
authors.initials: K
authors.lastname: Cox
authors.forename: Melissa
authors.initials: M
authors.lastname: Hurwitz
authors.forename: Jennifer
authors.initials: J
authors.lastname: Huang
authors.forename: Christine
authors.initials: C
authors.lastname: Nguyen
authors.forename: J Antonio
authors.initials: JA
authors.lastname: Quiros
authors.forename: Kari
authors.initials: K
authors.lastname: Nadeau
mesh_terms: D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000378:metabolism; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D057765:Eosinophilic Esophagitis / Q000276:immunology* / Q000378:metabolism; D004947:Esophagus / Q000276:immunology* / Q000378:metabolism; D005260:Female; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism*; D005764:Gastroesophageal Reflux / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007223:Infant; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism*; D055815:Young Adult
chemical_list: D015703:Antigens, CD; D051858:Forkhead Transcription Factors; D012333:RNA, Messenger