TLR7 expression on circulating precursor myeloid dendritic cells (pre-mDCs) and mDCs in patients with adult-onset Still's disease (AOSD), patients with systemic lupus erythematosus (SLE), and healthy volunteers. Representative examples (A) of flow cytometric histograms of Toll-like receptor (TLR)7 expression in mDcs (mDCs) obtained from peripheral blood of one representative patient with active AOSD, a patient with SLE and a healthy control (HC). The frequencies and mean fluorescence intensity (MFI) of TLR7 expression on circulating pre-mDCs [CD14+CD11c+ cells] (B and C, respectively) and mDCs [CD14-CD11c+ cells] (D and E, respectively) were obtained from 28 patients with active AOSD, 28 with active patients, and 12 HCs. The horizontal line indicates the median value for each group. The P-value was determined by the Mann-Whitney U-test.