LECTIN-BINDING IN BONE-MATRIX OF ADULT-RATS WITH SPECIAL REFERENCE TOCEMENT LINES

The present study was designed to localize glycoconjugates recognized by four lectins (LFA, MPA, WGA, and ConA) in adult rat bone, histochem ically and biochemically. LFA, a lectin recognizing sialic acid, stain ed intensely the cement lines of calvariae and the interface between c artilage and bone of mandibular condyles, which were also stained with WGA, and intermittently stained with ConA. The irregular bone surface of calvariae displayed intense positive reaction with LFA and WGA, wh ile the osteoid of mandibular condyles and the smooth bone surface of calvariae were intensely stained with WGA and ConA, but weakly stained with LFA and MPA. MPA recongnized osteoclasts. At the superficial lay er of mandibular condyles, the bone matrix appeared positive as granul es with LFA and as patches with MPA, WGA and ConA. Lectin blotting ana lysis of bone extracts revealed two LFA positive bands at molecular we ights of 18 kDa and 45 kDa. The former was positive with WGA, ConA, an d MPA, while the latter mas positive with MPA. The result suggests tha t the LFA-binding glycoconjugates, possibly 18 kDa and/or 45 kDa sialo glycoconjugates, may contribute to cementing mechanism of cement lines and/or to the bone formation in remodeling process as well as in intr amembranous and intracartilaginous osteogenesis.