In recent years there has been a focus on the possible use of A3 AR agonists as therapeutic compounds in rheumatoid arthritis; IB-MECA (A3 AR agonist) reduced pannus and fibrosis formation, cartilage and bone destruction, and the latter via a decrease in the number of osteoclasts in the adjuvant mouse model (Rath-Wolfson et al., 2006). Here, ADORA3 is linked to rheumatoid arthritis.