title: Use of bone morphogenetic protein 2 on ectopic porous coated implants in the rat.
abstract: The ability of recombinant human bone morphogenetic protein 2 to remain osteoinductive and stimulate appositional bone formation on a porous coated implant was tested in a rat quadriceps muscle pouch. Implants with or without hydroxyapatite were used to compare the effects on bone formation of two different does (23 micrograms or 46 micrograms) of recombinant human bone morphogenetic protein 2 against controls as evidenced by contact radiography, histologic examination, and backscatter scanning electron microscopic analysis. Cylindrical plasma sprayed porous titanium implants were placed bilaterally within a muscle pouch surgically created in 48 Lewis rats. Implants treated with recombinant human bone morphogenetic protein 2 formed significantly more bone than did control implants independent of the dose or presence of hydroxyapatite. In all implants with bone formation, osteoinduction via endochondral ossification began within 7 days. By 21 days, cartilage largely was replaced by bone and marrow. The results of this ectopic, nonweightbearing in vivo assay suggest that recombinant human bone morphogenetic protein 2 remains biologically active after application to a titanium implant and may be used to enhance appositional bone formation by direct application to the implant surface.
authors.affiliation: Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL, USA.
authors.forename: B J
authors.initials: BJ
authors.lastname: Cole
authors.forename: M P
authors.initials: MP
authors.lastname: Bostrom
authors.forename: T L
authors.initials: TL
authors.lastname: Pritchard
authors.forename: D R
authors.initials: DR
authors.lastname: Sumner
authors.forename: E
authors.initials: E
authors.lastname: Tomin
authors.forename: J M
authors.initials: JM
authors.lastname: Lane
authors.forename: A J
authors.initials: AJ
authors.lastname: Weiland
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001853:Bone Marrow / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000737:chemistry / Q000494:pharmacology*; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D002356:Cartilage / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D016009:Chi-Square Distribution; D017886:Durapatite / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology; D009999:Ossification, Heterotopic / Q000139:chemically induced; D010012:Osteogenesis / Q000187:drug effects; D016062:Porosity; D019736:Prostheses and Implants; D019919:Prosthesis Implantation; D011859:Radiography; D051381:Rats; D011917:Rats, Inbred Lew; D011994:Recombinant Proteins; D016037:Single-Blind Method; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D016212:Transforming Growth Factor beta / Q000737:chemistry / Q000494:pharmacology*
chemical_list: C525718:BMP2 protein, human; C525720:Bmp2 protein, rat; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; D017886:Durapatite; D014025:Titanium