– Galectins are a family of carbohydrate-binding proteins with specificity for N-acetyl-lactosamine-containing glycoproteins. Galectin-4 is a 36 kDa tandem-repeat galectin found throughout the gastrointestinal tract, but also present in well-differentiated breast and liver carcinomas. Galectin-4 expression is concentrated within microvilli in the gastrointestinal epithelium, where it can interact with CD3 and bind activated T cells in the lamina propria during intestinal inflammation.