Comparison of the osteoinductivity of bioimplants containing recombinant human bone morphogenetic proteins 2 (Infuse) and 7 (OP-1).
OBJECTIVE
Recent research has focused on application of growth factors such as bone morphogenetic proteins (BMPs) as alternatives to autogenous bone grafting. Two bone graft substitute bioimplants containing recombinant human BMPs (rhBMPs), Infuse (rhBMP-2) and OP-1 (rhBMP-7), are approved for human application but have never been compared side by side. The aim of this study was to provide a direct comparison of the osteoinductive activity of the 2 commercially available and approved rhBMP-containing bioimplants in their clinically available forms.


METHODS
The activity of rhBMP-2 and -7 in solution were compared in vitro using the C2C12 cell-based assay. The activity of Infuse and OP-1 bioimplants containing 52.5 microg of rhBMP-2 or rhBMP-7, respectively, were compared in vivo using a mouse muscle pouch assay and analyzed by microscopic CT (microCT) and histology.


RESULTS
The in vitro results showed that rhBMP-2 stimulated greater alkaline phosphatase production than rhBMP-7 over various time points and concentrations. The in vivo results showed that OP-1 induced greater bone volume than Infuse. Both implants induced bone of equivalent quality based on microCT and histologic evaluation.


CONCLUSIONS
In their clinically available forms, the rhBMP-7-containing OP-1 induced greater bone volume than the rhBMP-2-containing Infuse in the mouse muscle pouch model.
Barr
Torin
T
Oral and Maxillofacial Surgery and Anesthesia, University of Toronto, Toronto, Ontario, Canada.
McNamara
Audrey J A
AJ
Sándor
George K B
GK
Clokie
Cameron M L
CM
Peel
Sean A F
SA
D000469:Alkaline Phosphatase / Q000187:drug effects; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology*; D015519:Bone Density / Q000187:drug effects; D001853:Bone Marrow / Q000187:drug effects; D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7 / Q000494:pharmacology*; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D018786:Bone Substitutes / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects; D003094:Collagen; D004337:Drug Carriers; D006801:Humans; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D018482:Muscle, Skeletal / Q000166:cytology / Q000187:drug effects / Q000601:surgery; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects; D010011:Osteocytes / Q000166:cytology / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects*; D011994:Recombinant Proteins / Q000494:pharmacology*; D013848:Thigh / Q000601:surgery; D054457:Tissue Scaffolds; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D055114:X-Ray Microtomography
C525819:BMP7 protein, human; D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D018786:Bone Substitutes; D004337:Drug Carriers; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; D003094:Collagen; D000469:Alkaline Phosphatase