Galectin-1

Galectin-1 is a β-galactoside-binding protein with intracellular and extracellular activity, and evidence identifies Galectin-1 and its ligands as regulators of T-cell homeostasis, survival, immune disorders, inflammation, allergies, and host-pathogen interactions^[1]. Mechanistically, Galectin-1 regulates immune and inflammatory cells through carbohydrate-dependent binding and cross-linking of cell-surface glycoproteins, including CD2, CD3, CD7, CD43, and CD45 on T cells^[1]. In disease models, Galectin-1 inhibited microglial activation and ameliorated neurodegeneration in a Parkinson’s disease model through the MAPK/IκB/NFκB axis and its carbohydrate-recognition domain^[2]. In collagen-induced arthritis, absence of endogenous Galectin-1 increased susceptibility and disease severity, supporting its inhibitory role in experimental inflammation^[3]. Compared with related isoforms, Galectin-1 and Galectin-3 bind distinct T-cell surface glycoprotein receptors, while Galectin-9 and Galectin-1 require different glycan ligands and glycoprotein receptors to trigger T-cell death^[4][5]. For experimental oncology applications, Galectin-1 overexpression was detected in hepatocellular carcinoma, and OTX008 combined with sorafenib significantly reduced tumor growth and size in tumor-cell models^[6].