IL10 and rheumatoid arthritis: To further elucidate the roles of IL-10 in monocyte maturation, blood monocytes from two patients with RA were incubated for 12 hours with or without IL-10 and the gene expression profile was analysed by an microarray that detects 367 known genes that encode for cytokines, chemokines and their receptors, cell surface markers, representative signaling proteins, and downstream targets of the signal transduction pathway.