Characterization of monoclonal antibodies recognizing bovine bone osteoglycin

Six monoclonal antibodies (mAb) are described that bound to the bovine bone glycoprotein, osteoglycin. The protein osteoglycin was originally called Osteoinductive Factor (OIF). The antibodies were characterized with respect to their reaction patterns in Western blots, indirect immunoprecipitation, and binding epitope. The antibodies bound to one of two sequential determinants, either residues 62-76 or 95-105, in the C-terminal region of mature osteoglycin. One mAb, 2C11, was found to be useful for affinity purification of osteoglycin. Another mAb, 3B2, was able to immunohistochemically stain osteoblasts, osteocytes, chondrocytes, occasional osteoclasts and nail bed epithelial cells in rat neonatal forelimb. The mAbs will provide an essential tool for the further characterization of this unique glycoprotein.