Recombinant human bone morphogenetic protein-7 induces healing in a canine long-bone segmental defect model.
An ulnar segmental defect model was used in adult male dogs to examine the effect of recombinant human bone morphogenetic protein-7 (recombinant human Osteogenic Protein-1 [rhOP-1]; Creative Biomolecules, Hopkinton, Massachusetts) on new bone induction and healing, and to test the mechanical strength of healed 2.5-cm segmental bone defects. The rhOP-1 composites consisted of a carrier of 500 mg of demineralized, guanidine-extracted, insoluble bovine bone matrix (collagen carrier), reconstituted with rhOP-1. Six animals received 1200 micrograms rhOP-1 unilaterally and were killed at 12 weeks for torsional load-to-failure testing using the contralateral side as a control. Two further animals received varying amounts of rhOP-1 bilaterally and were studied histologically. All defect sites receiving rhOP-1 were completely bridged radiographically by eight weeks. A control composite, containing no rhOP-1, failed to induce new bone formation at any time. Histologically, rhOP-1-treated sites examined at 16 weeks had formation of new cortical and cancellous bone, with normal appearing marrow elements in the reconstituted medullary canal. The torsional strength of the rhOP-1-implanted ulnae averaged 72% of control (range, 30-99%). The angular deformation to failure averaged 92% of control (range, 39-122%). The energy absorption to failure averaged 67% of control (range, 27-111%). This study demonstrates the efficacy of rhOP-1 in healing segmental osteoperiosteal defects in a canine model.
Cook
S D
SD
Department of Orthopaedic Surgery, Tulane University School of Medicine, New Orleans, Louisiana 70112.
Baffes
G C
GC
Wolfe
M W
MW
Sampath
T K
TK
Rueger
D C
DC
D000818:Animals; D019485:Bone Morphogenetic Proteins; D002417:Cattle; D003094:Collagen; D004285:Dogs; D004337:Drug Carriers; D006133:Growth Substances / Q000494:pharmacology*; D008297:Male; D010012:Osteogenesis / Q000187:drug effects*; D011506:Proteins / Q000494:pharmacology*; D011859:Radiography; D011994:Recombinant Proteins / Q000494:pharmacology; D016212:Transforming Growth Factor beta / Q000494:pharmacology; D014457:Ulna / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000601:surgery*
D019485:Bone Morphogenetic Proteins; D004337:Drug Carriers; D006133:Growth Substances; D011506:Proteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; D003094:Collagen