Furthermore, the plasma levels of CXCL8, CXCL12, and CXCL13 were significantly decreased 6 months after MSCs transplantation, suggesting that the interaction of MSCs with CXCL8-producing cells could be one of the possible mechanisms causing the reduced levels of CXCL8 in the joints and, subsequently, in the plasma of RA patients. The gene discussed is CXCL8; the disease is rheumatoid arthritis.