LRRC32 (leucine-rich repeat containing 32), also known as GARP (glycoprotein A repetitions predominant), is a key regulator of transforming growth factor beta (TGF-β) activation and latency. LRRC32 functions as a cell surface docking receptor that associates specifically with the latency-associated peptide (LAP) of TGF-β through disulfide bonds, maintaining TGF-β in an inactive state during extracellular storage 1. The protein outcompetes LTBP1 for LAP binding and regulates integrin-dependent TGF-β activation 1. LRRC32 is particularly important on regulatory T cells (Tregs), where it controls TGF-β1 surface activation and serves as a safeguard of the regulatory phenotype through positive feedback with FOXP3 2. Recent structural studies reveal that integrin αvβ8 binding induces dynamic allosteric conformational changes in latent TGF-β1-LRRC32 complexes, enabling receptor signaling without complete TGF-β release 3. LRRC32 expression is critical for epithelial fusion during palate development. Clinical relevance extends to cancer immunotherapy, where LRRC32 overexpression promotes immunosuppression; anti-GARP antibodies enhance CD8+ T cell function and overcome resistance to checkpoint blockade 4. LRRC32 is implicated in eosinophilic esophagitis and other immune-mediated diseases 5.