Lectins are carbohydrate binding proteins that interact with glycoprotein and glycolipids on the surface of animal cells. The Galectins are lectins that recognize and interact with beta-galactoside moieties. Galectin-3 regulates a number of biological processes, including embryogenesis, inflammatory responses, cell progression and metastasis. Galectin-3 can function intracellularly in controlling cell cycle and preventing T-cell apoptosis, and also extracellularly, in activating various cells, including monocytes/macrophages, mast cells, neutrophils, and lymphocytes. Human Galectin-3 is a globular 26.0 kDa protein containing 250 amino acid residues.