Glycoprotein A repetitions predominant protein–transforming growth factor beta complex (GARP–TGF-β complex)

The **Glycoprotein A repetitions predominant protein–transforming growth factor beta complex** (GARP–TGF-β complex) is formed when GARP (also known as LRRC32), a type I transmembrane protein, binds to the latent form of transforming growth factor beta (LTGF-β) and tethers it to the cell surface of regulatory T cells (Treg) and platelets[1][5][7]. GARP acts as a docking receptor for LTGF-β, enabling its spatial presentation and regulated activation via interaction with specific integrins such as αVβ6 and αVβ8[1][2][3]. The complex plays a central role in immune tolerance and regulation: it enables Treg cells to mediate immunosuppressive effects by facilitating release of active TGF-β in a highly controlled manner[1][3][8]. GARP–TGF-β surface display is a key checkpoint for the initiation of TGF-β signaling relevant in development, wound healing, homeostasis, and cancer progression[1][4][5]. Pathologically, tumor cells can hijack this system to promote immune suppression and tumor progression, making the complex a promising target for novel immunotherapies, particularly via inhibitory antibodies that block TGF-β activation and signaling[2][5][8]. Safety challenges include the risk of dysregulated immune activation upon therapeutic targeting[5].

Other names

GARP–latent TGF-β complexGARP–LTGF-β complexLRRC32–TGF-β complex

Inhibition of TGF-β activation (by anti-GARP antibodies)[2]; Blockade of TGF-β signaling (by disrupting GARP–TGF-β interaction)[2]