NKG2A expression and impaired function of NK cells in patients with new onset of Graves' disease

• Number of NK cells decreased in GD.
• Function of NK was impaired in GD.
• NK may contribute to the pathogenesis of GD.

BackgroundGraves' disease (GD) is an organ-specific autoimmune disease. A significant decrease of the distribution of NK cells in the peripheral blood in children and adolescents with untreated GD has been observed. However, the role of NK and its subsets in adults with GD remains unclear.MethodsA total of 28 adult patients with new onset of GD and 23 healthy controls (HC) were recruited. The number of activated inhibitory NK cells in peripheral blood of individual subjects was determined by flow cytometry.ResultsThe number of CD3−CD56+ and CD3−CD16+NK cells in peripheral blood was significantly decreased in the GD patients than the HC. Compared to the HCs, decreased number of NKG2D+, NKG2C+, NKp30+ and NKG2A+ NK cells and increased number of KIR3DL1+ NK cells were detected in the GD patients. Moreover, the number of inducible CD107a+ and IFN-γ-secreting NK cells in GD patients significantly decreased than those in HC. Interestingly, the number of NKG2A+NK cells was negatively correlated with the level of serum TRAb in GD patients.ConclusionOur data indicate that decreased number and impaired function of NK cells may contribute to the pathogenesis of GD.