TGF-beta induced CD4+FoxP3+ cells prevent Th1 colitis: role of TGF-beta and exogenous IL–2

The unbalance between effectors cells and their regulation, at the basis of a pathologic immune response against harmless antigens expressed by the normal commensal flora contributes to the development of Inflammatory Bowel Diseases (IBDs). Tolerance is physiologically achieved by elimination of autoreactive clones of T cells in the thymus, but also through peripheral processes leading to anergy of T-cells reacting against harmless antigens or by the action of specialized regulatory cells. CD4+CD25+ regulatory T cells have been shown to mediate an important immunomodulatory effect. These cells are characterized…