Abstract
Rheumatoid arthritis (RA), one of the most common articular diseases, is characterized by chronic inflammation, hyperproliferation of synovial cells, and bone destruction. CD81, which belongs to a family of cell-surface proteins (tetraspanin), is known to be up-regulated in RA synoviocytes. Recently, we showed the therapeutic effect of using small interfering RNA in targeting CD81 (CD81 siRNA) for RA. Here we show how tumor necrosis factor-alpha (TNF-α) can induce the expression of synoviolin, which is decreased by the addition of CD81 siRNA in SW982 cells. In addition, CD81 siRNA decreases the expression of TNF-α in SW982 cells, suggesting that TNF-α stimulates the expression of synoviolin via CD81. Furthermore, knock down of CD81 by the addition of CD81 siRNA decreases the expression of TNF-α, and TNF-α-induces expression of synoviolin in direct and indirect ways. These results in SW982 cells might explain the therapeutic effect of CD81 siRNA in animal models.
