Role for GARP-TGF-beta on B cells in immune tolerance

The transmembrane protein GARP serves as a receptor for latent TGF-beta , resulting in activation of this cytokine. GARP is expressed on the surface of Tregs, tumors, and platelets and has been implicated in cancer immune invasion. In this episode, Zihai Li and colleagues reveal that the GARP-TGF-beta complex is present on activated, but not resting, human and murine B cells. Using multiple murine genetic models, the authors determined that this complex is essential for maintaining immune tolerance and for preventing autoimmune disease. These results support further exploration of B cell GARP as a therapeutic target and possible diagnostic tool for autoimmune disease.