title: Altered proportions of naïve, central memory and terminally differentiated central memory subsets among CD4+ and CD8 + T cells expressing CD26 in patients with type 1 diabetes.
abstract: Type 1 diabetes is an autoimmune process predominantly T-cell mediated. CD26 plays a role in T-cell costimulation, migration, memory development, thymic maturation and emigration patterns. In peripheral blood from 55 patients with type 1 diabetes and 20 healthy controls, CD4(+) and CD8(+) T cells expressing CD26 were differentiated into naïve (N, CD45RA(+)CCR7(+)), central memory (CM, CD45RA(-)CCR7(+)), effector memory (EM, CD45RA(-)CCR7(-)), and terminally differentiated effector memory (TEMRA, CD45RA(+)CCR7(-)). In type 1 diabetes, CD4(+) and CD8(+) T cells expressing CD26 showed a distinctive differentiation profile: percentages and absolute numbers of CM and N cells were reduced, whereas those of TEMRA cells were markedly increased. The indices of intermediate- and long-term glycaemic control were associated negatively with the number of CM and N cells while positively with the number of TEMRA cells. The considerable accumulation of TEMRA T cells in our patients suggests life-long stimulation by protracted antigen exposure (viruses, other agents or residual self-antigens?) or a homeostatic defect in the regulation/contraction of immune responses.
authors: Department of Internal Medicine, University of Pisa, Via Roma 67, 56126, Pisa, Italy. elena.matteucci@med.unipi.it
authors: Elena
authors: E
authors: Matteucci
authors: Massimo
authors: M
authors: Ghimenti
authors: Serena
authors: S
authors: Di Beo
authors: Ottavio
authors: O
authors: Giampietro
mesh_terms: D000293:Adolescent; D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D002454:Cell Differentiation; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology* / Q000473:pathology; D018819:Dipeptidyl Peptidase 4 / Q000378:metabolism*; D005260:Female; D006801:Humans; D007156:Immunologic Memory; D016130:Immunophenotyping; D007223:Infant; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D054400:Receptors, CCR7 / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism* / Q000473:pathology
chemical_list: C515370:CCR7 protein, human; D054400:Receptors, CCR7; D017493:Leukocyte Common Antigens; D018819:Dipeptidyl Peptidase 4