title: Circulating CD4+CD25 high regulatory T cells and natural killer T cells in children with newly diagnosed type 1 diabetes or with diabetes-associated autoantibodies.
abstract: Type 1 diabetes is a T-cell-mediated autoimmune disease in which insufficient regulatory mechanisms are perceived to be involved in the pathogenesis. We used flow cytometry to analyze the proportion of CD4(+)CD25(high) regulatory T cells and natural killer T (NKT) cells in peripheral blood obtained from 25 children with newly diagnosed type 1 diabetes, 21 nondiabetic subjects positive for two or more diabetes-associated autoantibodies, and from 39 autoantibody-negative age- and HLA-matched control subjects. CD4(+)CD25(high) T cells were also stained for additional markers HLA-DR, CD69, and CD62L. As NKT cell markers, we used CD161, V beta 11, and V alpha 24. The frequency of CD4(+)CD25(high)HLA-DR(-) T cells was significantly higher in multiple autoantibody-positive children than in controls (P = 0.021). We also detected a significantly higher level of CD4(+)CD25(high)HLA-DR(-) and CD4(+)CD25(high)CD69(-) T cells among children expressing three to four autoantibodies when compared to the controls (P = 0.004 and P = 0.048, respectively). The proportions of CD161(+)V beta 11(+) or V alpha 24(+)V beta 11(+) NKT cells were similar in all three groups of children studied. Interestingly, children with only two autoantibodies had a higher level of CD161(+)V beta 11(+) NKT cells than the controls (P = 0.002). Our data might be interpreted as indicative of an intensified regulatory response of regulatory T cells and NKT cells during the preclinical phase of the disease.
authors.affiliation: University of Turku, Immunogenetics Laboratory, Medicity Biocity 4th floor, Tykistökatu 6 A, 20520 Turku, Finland. viveka.oling@utu.fi
authors.forename: Viveka
authors.initials: V
authors.lastname: Oling
authors.forename: Jane
authors.initials: J
authors.lastname: Marttila
authors.forename: Mikael
authors.initials: M
authors.lastname: Knip
authors.forename: Olli
authors.initials: O
authors.lastname: Simell
authors.forename: Jorma
authors.initials: J
authors.lastname: Ilonen
mesh_terms: D015703:Antigens, CD / Q000276:immunology / Q000378:metabolism; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology / Q000378:metabolism; D001323:Autoantibodies / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism*; D002465:Cell Movement; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000175:diagnosis* / Q000276:immunology* / Q000378:metabolism; D005260:Female; D006684:HLA-DR Antigens / Q000276:immunology; D006801:Humans; D053645:Interleukin-2 Receptor alpha Subunit / Q000276:immunology / Q000378:metabolism*; D037181:Lectins, C-Type; D008297:Male; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism; D000099192:CD69 Antigens