CXCR4 and rheumatoid arthritis: Nonclassical monocytes showed a specific transcriptomic profile of 19 differentially expressed genes not shared with other cell subsets (Figure 3, B and C), including a downregulation of ETNK1, TNFSF13B, DUSP7, and IGSF6 and an upregulation of CXCR4 in RA.