Because our results showed that PKD1 is activated and essential for the TLR/IL-1R-induced cytokine and chemokine expression in HFLS isolated from patients with RA, we thought that a pharmacological agent that can inhibit TLR/IL-1R-mediated PKD1 activation may have ameliorating effects on arthritis. Here, IL1R1 is linked to rheumatoid arthritis.