Regulatory T Cells and Rheumatoid Arthritis

Regulatory T (Treg) cells play a crucial role in controlling autoimmunity by inflammatory by suppressing auto reactive T cells. Treg cells generated in the thymus are called natural Treg cells. Treg cells could also be generated outside the thymus from peripheral naive CD4+CD25+ T cells under both in vitro and in vivo conditions and are referred as adaptive or induced Treg cells. The fork-head transcription factor (Foxp3) is the master regulator for the development and function of Treg cells. Treg cells in rheumatoid arthritis (RA) patients have a defect in their ability to suppress proinflammatory cytokine production by activated T cells and monocytes. Also, deficiency of Foxp3 results in the paucity of CD4+CD25+ Treg cells and leads to severe multiorgan autoimmune diseases in both mice and humans. Thus, the development of functional Treg cells holds promise for the treatment of RA and other autoimmune diseases. In this review, I discuss the potential of Treg cells in treating RA and various other autoimmune diseases.