The activity of JAK-STAT pathways in rheumatoid arthritis: constitutive activation of STAT3 correlates with interleukin 6 levels
Rheumatology (Oxford). 2014 Nov 17. pii: keu430. [Epub ahead of print]
This study examined the expression and phosphorylation of STAT1 and STAT3 in unstimulated T cells and monocytes, and their activation by cytokines IFN-g, IL-6 and IL-10, using real-time PCR and multicolour flow cytometric analysis on samples from patients with active RA.
The results of the study show that; expression and phosphorylation of STAT3 are elevated in circulating T cells and monocytes in RA; baseline activation of STAT3 in RA correlates with IL-6 levels; a proportion of RA T cells are hyporesponsive to IL-6-mediated STAT3 activation in vitro. These finding suggest that a synthetic inhibitor that would specifically target the IL-6/STAT3 signalling pathway might have beneficial therapeutic characteristics in RA.