German research find way to specifically switch off autoimmunity
Essen – German researchers have found a way to turn immune effector cells – such as T-helper cells, which attack specific antigens on the surface of transplants – into immunosuppressive regulatory T-cells (Tregs) (J. Cell Mol.Med., doi: 10.111/j.1582-4934.2009.00782.x). The research group under Jan Buer from Essen University hospital succeeded in reprogramming T-effector cells into Tregs through overexpression of the newly discovered FoxP3 regulator GARP. In contrast, GARP inhibition in Tregs abolished their immunosuppressive effects. According to Buer, GARP is exclusively expressed in Tregs, and is the long-awaited marker that makes it possible to distiguish T-cell populations that carry the same surface antigens (CD4+ CD25+) but differ concerning the immunosuppressive phenotype. The discovery opens a way to switch off specific T-effector cell populations, a possible approach for treating autoimmune diseases.