When cultured on bone , VR + , TRAP + cells of low multinuclearity appear and cover up to 50% of the surface .
when cultured on bone , vr + , trap + cells of low multinuclearity appear and cover up to 50% of the surface .
O O O B-tissue O B-protein_family_or_group O O B-protein_molecule O O O O O O O O O O O O O O O