Increased number of regulatory T cells in children with eosinophilic esophagitis.
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.
Fuentebella
Judy
J
Department of Pediatrics, Lucile Packard Children's Hospital, Stanford University Medical Center, Palo Alto, CA, USA. judy.fuentebella@gmail.com
Patel
Anup
A
Nguyen
Tammie
T
Sanjanwala
Bharati
B
Berquist
William
W
Kerner
John A
JA
Bass
Dorsey
D
Cox
Kenneth
K
Hurwitz
Melissa
M
Huang
Jennifer
J
Nguyen
Christine
C
Quiros
J Antonio
JA
Nadeau
Kari
K
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
D015703:Antigens, CD; D051858:Forkhead Transcription Factors; D012333:RNA, Messenger