ReviewGalectin-1 research in T cell immunity: Past, present and future

Galectin-1 (Gal-1) is one of 15 evolutionarily conserved ß-galactoside-binding proteins that display biologically-diverse activities in pathogenesis of inflammation and cancer. Gal-1 is variably expressed on immune cells and endothelial cells, though is commonly found and secreted at high levels in cancer cells. It induces apoptosis in effector T cells through homodimeric binding of N-acetyllactosamines on membrane glycoproteins (Gal-1 ligands). There is also compelling evidence in models of cancer and autoimmunity that recombinant Gal-1 (rGal-1) can potentiate immunoregulatory function of T cells. Here, we review Gal-1's structural and functional features, while analyzing potential drawbacks and technical difficulties inherent to rGal-1's nature. We also describe new Gal-1 preparations that exhibit dimeric stability and functional activity on T cells, providing renewed excitement for studying Gal-1 efficacy and/or use as anti-inflammatory therapeutics. We lastly summarize strategies targeting the Gal-1-Gal-1 ligand axis to circumvent Gal-1-driven immune escape in cancer and boost anti-tumor immunity.

► Galectin-1 (Gal-1) has profound effects on inflammation and cancer. ► Gal-1 research is limited due to functional instability of Gal-1. ► Gal-1-Human Ig chimeras are effective for exploring Gal-1 ligands on cells. ► Gal-1-Gal-1 ligand axis is a compelling anti-inflammatory/-cancer target.