title: Peripheral and Intestinal T-regulatory Cells are Upregulated in Children with Inflammatory Bowel Disease at Onset of Disease.
abstract: OBJECTIVE
  To determine the proportion of T-regulatory cells (CD4+CD25highFOXP3+cells) in peripheral blood and the number of FOXP3+cells in intestinal mucosa of children with inflammatory bowel disease (IBD), and to verify whether these parameters correlate with the activity of the disease.
  
  
  METHODS
  24 patients newly diagnosed for IBD were included in the study: ulcerative colitis (UC; n = 13) and Crohn's disease (CD; n = 11). Seventeen healthy controls (HC) and 16 patients with irritable bowel syndrome (IBS) served as a control group for peripheral and intestinal Tregs assessment, respectively. The disease activity was assessed by Pediatric Ulcerative Colitis Activity Index (PUCAI) and Pediatric Crohn's Disease Activity Index (PCDAI). Quantification of regulatory T cells of CD4+CD25highFOXP3+phenotype in peripheral blood was based on three-color flow cytometry. Mucosal Tregs represented by FOXP3+cells were evaluated using immunohistochemistry.
  
  
  RESULTS
  Median proportion of CD4+CD25highFOXP3+cells among CD4+T cells in peripheral blood (5.1%, range 1.7-84% vs. 4.3%, range 2-8.1%, p = 0.023) and median number of intestinal FOXP3+ cells (115.33 per high-power field, hpf, range 39.33-375.67 vs. 10.16 per hpf, range 5-30, p = 0.0001) were significantly higher in children with IBD than in the controls. The proportion of circulating Tregs and the number of intestinal FOXP3+ cells did not correlate with clinical activity of the disease, as well as with endoscopic and histopathologic scoring. No significant correlation was found between the percentage of peripheral CD4+CD25highFOXP3+ cells and the number of intestinal FOXP3+cells.
  
  
  CONCLUSIONS
  Children with IBD likely do not present with a quantitative deficiency of circulating and intestinal Tregs at the moment of diagnosis.
authors.affiliation: a Department of Pediatrics, Pediatric Gastroenterology , Hepatology and Nutrition, Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Sznurkowska
authors.affiliation: b Department of Pathology , Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Anton
authors.initials: A
authors.lastname: Żawrocki
authors.affiliation: c Department of Surgical Oncology ; Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Jacek
authors.initials: J
authors.lastname: Sznurkowski
authors.affiliation: d Department of Clinical Immunology and Transplantology , Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Zieliński
authors.affiliation: a Department of Pediatrics, Pediatric Gastroenterology , Hepatology and Nutrition, Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Landowski
authors.affiliation: a Department of Pediatrics, Pediatric Gastroenterology , Hepatology and Nutrition, Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Plata-Nazar
authors.affiliation: e Department of Pathology and Neuropathology , Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Iżycka-Świeszewska
authors.affiliation: d Department of Clinical Immunology and Transplantology , Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Trzonkowski
authors.affiliation: a Department of Pediatrics, Pediatric Gastroenterology , Hepatology and Nutrition, Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Szlagatys-Sidorkiewicz
authors.affiliation: a Department of Pediatrics, Pediatric Gastroenterology , Hepatology and Nutrition, Medical University of Gdańsk , Gdańsk , Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Kamińska
keywords: IBD; T-regulatory cells; inflammatory bowel disease; intestinal Tregs; peripheral Tregs