A High Frequency of Peripheral Blood IL-22(+) CD4(+) T Cells in Patients With New Onset Type 2 Diabetes Mellitus.

BACKGROUND: This study is aimed at investigating the frequency of different functional IL-22(+) CD4(+) T cells in Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: The frequency of circulating IFN-γ+IL-17-IL-22-CD4(+) (Th1), IFN-γ-IL-17A+IL-22-CD4(+) (Th17), and IFN-γ-IL-17A-IL-22(+) CD4(+) (Th22), and other subsets of IL-22(+) CD4(+) T cells in 31 patients with new onset T2DM and 16 healthy controls was characterized by flow cytometry. The levels of serum IL-22, IL-17, IFN-γ, insulin C-peptide, hemoglobin A1c (HbA1c), fasting plasma glucose, and insulin were examined. RESULTS: The frequency of Th1, Th17, Th22, IFN-γ(+) IL-17(-) IL-22(+) , and IFN-γ(-) IL-17(+) IL-22(+) CD4(+) T cells and the concentrations of IL-22, but not IL-17 and IFNγ, in the patients were significantly higher than controls. The percentages of Th22 cells were correlated positively with the frequency of IFN-γ(-) IL-17(+) IL-22(+) CD4(+) T cells, the values of body mass index (BMI) and homeostatic model assessment insulin resistance (HOMA-IR), and the levels of serum IL-22 in those patients. CONCLUSION: Our data suggest that IL-22(+) CD4(+) T cells may contribute to the early process of T2DM.

A higher frequency of circulating IL-22(+)CD4(+) T cells in Chinese patients with newly diagnosed Hashimoto's thyroiditis.

BACKGROUND: IL-22 and IL-17A are implicated in the pathogenesis of autoimmune diseases. However, the role of IL-22(+) and IL-17A(+) CD4(+) T cells in the pathogenesis of Hashimoto's thyroiditis (HT) is not fully understood. This study investigates serum IL-22 and IL-17A levels and determines the frequency of circulating IL-22(+) CD4(+) T cells in HT patients to understand their roles in the pathogenesis of HT. METHODS: The levels of serum IL-22, IL-17A and IFN-γ and the frequency of circulating IL-22(+)CD4(+) and IL-17A(+)CD4(+) T cells in 17 HT patients and 17 healthy controls (HC) were determined by enzyme-linked immunosorbent assay (ELISA) and flow cytometry. The levels of serum free triiodothyronine (FT4), free thyroxine (FT3), thyroid stimulating hormone (TSH), anti-thyroid peroxidase (TPO) and anti-thyroglobulin antibodies (TgAb) by chemiluminescent enzyme immunoassay and radioimmunoassay. RESULTS: The percentages of circulating IL-22(+)CD4(+) and IL-17(+)CD4(+) T cells (p<0.0001, p<0.0001) and the levels of serum IL-22, IL-17A and IFN-γ (p<0.0001, p<0.0001, p = 0.0210) in the HT patients were significantly higher than that in the HC. The percentages of IL-22(+)CD4(+) T cells were positively correlated with Th17 cells (r = 0.8815, p<0.0001) and IL-17A(+)IL-22(+)CD4(+) T cells (r = 0.8914, p<0.0001), but were negatively correlated with Th1 cells (r = -0.6110, p<0.0092) in the HT patients. The percentages of Th22 cells, Th17 cells and IL-17A(+)IL-22(+)CD4(+) T cells were negatively correlated with the levels of serum TSH in the HT patients (r = -0.8402, p<0.0001; r = -0.8589, p<0.0001; r = -0.8289 p<0.0001, respectively). CONCLUSIONS: A higher frequency of circulating IL-22(+)CD4(+) and IL-17A(+)CD4(+) T cells may be associated with the development of HT in Chinese patients.