CD200Fc reduced T-helper type 17 cell differentiation in systemic lupus erythematosus patients. (A) Peripheral blood mononuclear cells from systemic lupus erythematosus (SLE) patients (n = 9) or healthy controls (HCs) (n = 6) were co-cultured with CD200Fc for 48 hours. PE, phycoerythrin. (B) Percentages of T-helper type 17 (Th17) cells detected by flow cytometry. Numbers indicate the percentage of Th17 cells in CD4+ T cells.