CD19 and rheumatoid arthritis: TLR10 levels in B cells and B cell subsets (CD19+CD27+, CD19+CD27−, CD27+IgD−, CD27+IgD+, CD27−IgD+, D27−IgD−, CD19+CD5+, and CD19+CD5−) and inflammatory biomarker concentrations in peripheral blood (PB) obtained from RA subjects and HCs were detected by flow cytometry and enzyme-linked immunosorbent assay (ELISA), respectively.