title: The role of Treg cells and FoxP3 expression in immunity of β-thalassemia major AND β-thalassemia trait patients.
abstract: There is increased susceptibility to infections in β-thalassemia. Changes in T- and B-lymphocyte subsets and functions, defective chemotaxis, and phagocytosis of neutrophils and macrophages have been described in these patients. Regulatory T cells (Treg cells) play a crucial role in the maintenance of immunological self-tolerance. The FOXP3 gene is specifically expressed on Treg cells. Increased antigenic stimuli due to repeated blood transfusions might change the Treg cells and FOXP3 percentage in β-thalassemia. Immune functions of peripheral blood lymphocytes, percentage of Treg cells (defined as CD4(+)CD25(+)FoxP3(+)) were evaluated in 30 β-thalassemia major, 30 β-thalassemia trait, and 20 healthy children. Percentage of CD4(+)CD45RA(+) cells were increased in β-thalassemia trait compared to both β-thalassemia major and controls, whereas percentage of CD4(+)CD45RO(+) cells were higher in β-thalassemia major and trait patient compared to controls. Percentages of CD4(+)CD25(bright) and CD4(+)CD25(+)FoxP3(+) Treg cells were increased only in β-thalassemia major patients compared to controls (P = .001 and P = .0001, respectively). T lymphocytes express activated phenotype both in β-thalassemia major and trait patients. However, only in β-thalassemia major patients who were exposed to chronic antigenic stimulus as a result of repeated blood transfusions was an increase observed in Treg cells, which might suppress immune activation status.
authors.affiliation: Department of Pediatric Allergy and Immunology, Acibadem Healthcare Group, Acibadem Hospital, Istanbul, Turkey.
authors.forename: Gunseli
authors.initials: G
authors.lastname: Bozdogan
authors.forename: Ela
authors.initials: E
authors.lastname: Erdem
authors.forename: Gulderen Yanikkaya
authors.initials: GY
authors.lastname: Demirel
authors.forename: Yildiz
authors.initials: Y
authors.lastname: Yildirmak
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D051858:Forkhead Transcription Factors / Q000096:biosynthesis* / Q000097:blood / Q000276:immunology; D006801:Humans; D007109:Immunity; D007223:Infant; D008297:Male; D016176:T-Lymphocyte Subsets / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D055815:Young Adult; D017086:beta-Thalassemia / Q000097:blood / Q000276:immunology*
chemical_list: C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors