Galectins are a family of soluble β-galactoside-binding animal lectins that modulate cell-to-cell and cell-to-ECM interactions, as well as apoptosis. Galectin-1 has the ability to induce apoptosis of activated T-cells and T-leukaemia cell lines. Other activities include cell differentiation and inhibition activity of CD45 protein phosphatase activity. Galectin also binds beta-galactoside as well as CD45, CD3 and CD4. Human Galectin is a 14.5 kDa protein consisting of 134 amino acid residues.