Changes of plasmacytoid dendritic cells in peripheral blood and its role in the pathogenesis of systemic lupus erythematosus

Abstract

Objective To investigate the changes of plasmacytoid dendritic cells (pDC) in peripheral blood of patients with systemic lupus erythematosus(SLE) and its roles in the pathogenesis of SLE.Methods The level of pDC and the expressions of CD32,CD40,CD86,CD62L and CXCR4 were analyzed by flow cytometry.The concentrations of IFN-α in serum were detected by ELISA assay.Results The levels of circulating pDC were significantly decreased in SLE patients compared with healthy controls.Moreover,the pDC levels in active SLE patients were lower than those in inactive SLE patients,and compared with the primary group,the pDC levels were increased in the treatment group.The levels of pDC showed a significant decrease in SLE patients with arthritis,proteinuria or leucopenia in comparison with patients without those manifestations,showing a negative correlation with proteinuria.The expressions of cell surface molecules including CD32,CD86,CD62L and CXCR4 on pDCs were significantly increased in SLE patients compared with healthy controls,and the levels of pDC were negatively correlated with the expressions of CD32 and CXCR4 in patients with SLE.The concentrations of IFN-α in serum of patients with SLE were significantly higher than those in healthy controls,and the levels of pDC were positively correlated with the concentrations of IFN-α in patients with SLE.Conclusion The level of circulating pDC in patients with SLE was remarkably reduced,but the expressions of molecules involved in cell activation and migration were upregulated,accompanied by enhanced IFN-α production,which might promote the onset and progression of SLE. Key words: Systemic lupus erythematosus; Plasmacytoid dendritic cells; Surface molecule; IFN-α