title: Intact T cell responses in ataxia telangiectasia.
abstract: Ataxia telangiectasia (A-T) is an autosomal recessive multisystem disorder associated with a variable immune deficiency. The mechanism for this remains unclear. Qualitative and quantitative defects of cellular immunity have been previously reported. However, despite laboratory evidence of significant immune abnormalities, opportunistic infections are uncommon. To address this discrepancy, we analyzed cytokine production by quantitative real-time PCR and T cell function at the single cell level by flow cytometry in four A-T patients. CD4 and CD8 T cell subsets from these patients displayed intact signaling in response to anti-CD3 stimulation, similar to controls. Stimulated T cells from A-T patients also produced normal to increased levels of Th1 (IL-2, IFN-gamma) and Th2 (IL-10, IL-4) cytokines, relative to control values. Our results suggest that T cells from A-T patients may be more functionally intact than previously observed. This helps to explain the paucity of opportunistic infections encountered, unlike that encountered in other primary immunodeficiencies.
authors.affiliation: Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520, USA.
authors.forename: Farzana
authors.initials: F
authors.lastname: Pashankar
authors.forename: Vibha
authors.initials: V
authors.lastname: Singhal
authors.forename: Ike
authors.initials: I
authors.lastname: Akabogu
authors.forename: Richard A
authors.initials: RA
authors.lastname: Gatti
authors.forename: Frederick D
authors.initials: FD
authors.lastname: Goldman
mesh_terms: D015703:Antigens, CD / Q000096:biosynthesis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000096:biosynthesis; D001260:Ataxia Telangiectasia / Q000235:genetics / Q000276:immunology*; D017252:CD3 Complex / Q000096:biosynthesis; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D006801:Humans; D007111:Immunity, Cellular / Q000235:genetics; D016130:Immunophenotyping; D007223:Infant; D037181:Lectins, C-Type; D008297:Male; D009154:Mutation; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis; D013601:T-Lymphocytes / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*; D015854:Up-Regulation; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D016207:Cytokines; D037181:Lectins, C-Type; D015375:Receptors, Interleukin-2; D000099192:CD69 Antigens