CD27 and rheumatoid arthritis: Especially, RA patient CD27+IgD+ B cells expressed higher levels of chemokines and cytokines, including chemokine (C-C motif) ligand (CCL) 21, CCL20, chemokine (C-X-C motif) ligand (CXCL) 10, CXCL1, CXCL2, and interleukin 1α, demonstrating features of proinflammatory bias (Figure 5D).