Investigation of the change of CD4~+ T cell subset from children with type 1 diabetes
Objective To investigate the changes of CD4~+ T cell subset in the role of immuno-pathogenesis of type 1 diabetes mellitus(T1DM). Methods Real-time PCR was used to evaluate the ex-pression levels of transcriptional factors (T-bet, GATA-3, Foxp3, ROR-γt), cytokines (IFN-γ, IL-4, IL-10, IL-17A) and negative regulatory factors (CTLA-4, GITR) mRNA from CD4~+ T cells. The proportions of Th1, Th2, Tr and Th17 cells in peripheral blood were detected by flow cytometric analysis. Plasma cyto-kine (IFN-γ, IL-4, TGF-β and IL-6) concentrations were measured by enzyme-linked immunosorbent assay (ELISA). Results (1) The proportions of Th1 cells in peripheral blood from children with T1DM were siguificanfly increased than that of healthy controls, and proportions of Th2 were decreased (P 0.05). (2) Transcription levels of T-bet and IFN-γ mRNA were significantly up-regulated, while GATA3 and IL-4 were significantly down-regulated in children with T1DM. The mRNA expression levels of Tr negativity regulatory factors such as IL-10, CTLA-4 and GITR were lower in CD4~+ T cells from children with TIDM compared with the controls(P 0.05).(3) In comparison with controls, serum concentrations of IFN-γ or IL-4 were remarkable increased or de-creased respectively (P 0.05). Conclusion The Th1/Th2 imbalance might be play an important role in immunopathogenesis of T1DM. Functional deficiency of Tr cell might further exacerbate Th1/Th2 imbalance and lead to disturbance of cellu-lar immune response. 
 
Key words: 
T1DM;  Th1;  Th2;  Tr;  Th17