Mice with collagen-induced arthritis (CIA) show a reduced occurrence and severity of arthritis when TGF-β1 is intraperitoneally injected at late stages of disease progression [34, 43] and TGF-β1-transduced mouse bone marrow-derived mesenchymal stem cells, intraperitoneally injected in CIA mice, move to the affected joints and lead to reduced osteoclastogenesis verified by decreased expression of TRAP, cathepsin K or NFATc1 as well as decreased destruction of the articular cartilage, synovial hyperplasia, bone erosion and infiltration by inflammatory cells [44]. The gene discussed is TGFB1; the disease is Arthritis.