Lectin that recognizes O-linked galactose-beta-1,3-N-acetylgalactosamine, a disaccharide (Thomsen-Friedenreich antigen or T-disaccharide), present on cell surface glycoproteins. Can also bind chitin, N,N'-diacetylchitobiose, N-acetylgalactosamine and N-acetylglucosamine. Inhibits proliferation of colon, breast and liver cancer cell lines (in vitro). Homotetramer. Lectins can be used to recognize and purifiy specific glycoproteins, and for the purification of cells with specific surface glycoproteins. Has potential as anti-proliferative agent. Belongs to the fungal fruit body lectin family.