Bone Marrow Proteoglycan (BMPG) is a secreted protein that contains one C-type lectin domain. BMPG is the predominant constituent of the crystalline core of the eosinophil granule. BMPG is highly expressed in placenta and pregnancy serum. BMPG may be involved in antiparasitic defense mechanisms as a cytotoxin and helminthotoxin. BMPG induces non-cytolytic histamine release from human basophils. In addition, BMPG also participated in antiparasitic defense mechanisms and immune hypersensitivity reactions.