title: FOXP3+ regulatory T cells in children with helicobacter pylori infection.
abstract: Despite an intensive pro-inflammatory response, the immune system is unable to clear the organism in Helicobacter pylori gastritis. Regulatory T (Treg) cells, which suppress the immune response of antigen-specific T cells, have recently been demonstrated to play a key role in chronic inflammation by immunologic tolerance. The purpose of our study was to investigate the histopathology, FOXP3+CD4+CD25(high)Treg (FOXP3+Treg) cell expression, and immune responses in children with H. pylori infection. Twenty-four H. pylori -positive and 24 H. pylori -negative children who underwent esophagogastroduodenoscopy for dyspeptic symptoms were included. Histopathologic grading according to the updated Sydney classification and immunohistochemical stains for FOXP3, transforming growth factor-β1 (TGF-β1), and CD4 were performed. Histopathologic bacterial density score, gastritis activity score, and chronic inflammation score were higher in the H. pylori -positive group than in the negative group (P < 0.01). The number of FOXP3+Treg cells and CD4+T cells and the grade of TGF-β1 expression were significantly increased in the H. pylori -positive group compared to the negative group (P < 0.01). The number of FOXP3+Treg cells correlated positively with the grade of TGF-β1 expression regardless of H. pylori status (P < 0.05). The number of FOXP3+Treg cells and the grade of TGF-β1 expression correlated positively with H. pylori density, gastritis activity score, and chronic inflammation score regardless of H. pylori status (P < 0.01). These findings indicate that FOXP3+Treg cells could play a role in persistent H. pylori infection.
authors.affiliation: Department of Pediatrics, Ewha Womans University School of Medicine, Seoul 158-710, Korea.
authors.forename: Ky Young
authors.initials: KY
authors.lastname: Cho
authors.forename: Min Sun
authors.initials: MS
authors.lastname: Cho
authors.forename: Jeong Wan
authors.initials: JW
authors.lastname: Seo
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D051858:Forkhead Transcription Factors / Q000276:immunology; D005756:Gastritis / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000276:immunology* / Q000473:pathology; D016480:Helicobacter pylori / Q000276:immunology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D012189:Retrospective Studies; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors