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Evaluation of BMP-2 gene-activated muscle grafts for cranial defect repair.

ABSTRACT: Large, osseous, segmental defects heal poorly. Muscle has a propensity to form bone when exposed to an osteogenic stimulus such as that provided by transfer and expression of cDNA encoding bone morphogenetic protein-2 (BMP-2). The present study evaluated the ability of genetically modified, autologous muscle to heal large cranial defects in rats. Autologous grafts (8 mm × 2 mm) were punched from the biceps femoris muscle and transduced intraoperatively with recombinant adenovirus vector containing human BMP-2 or green fluorescent protein cDNA. While the muscle biopsies were incubating with the vector, a central parietal 8 mm defect was surgically created in the calvarium of the same animal. The gene-activated muscle graft was then implanted into the cranial defect. After 8 weeks, crania were examined radiographically, histologically, and by micro-computed tomography and dual energy X-ray absorptiometry. Although none of the defects were completely healed in this time, muscle grafts expressing BMP-2 deposited more than twice as much new bone as controls. Histology confirmed the anatomical integrity of the newly formed bone, which was comparable in thickness and mineral density to the original cranial bone. This study confirms the in vivo osteogenic properties of genetically modified muscle and suggests novel strategies for healing bone.

SUBMITTER: Liu F

PROVIDER: S-EPMC3349003 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Evaluation of BMP-2 gene-activated muscle grafts for cranial defect repair.

Liu Fangjun F Porter Ryan M RM Wells James J Glatt Vaida V Pilapil Carmencita C Evans Christopher H CH

Journal of orthopaedic research : official publication of the Orthopaedic Research Society 20111228 7

Large, osseous, segmental defects heal poorly. Muscle has a propensity to form bone when exposed to an osteogenic stimulus such as that provided by transfer and expression of cDNA encoding bone morphogenetic protein-2 (BMP-2). The present study evaluated the ability of genetically modified, autologous muscle to heal large cranial defects in rats. Autologous grafts (8 mm × 2 mm) were punched from the biceps femoris muscle and transduced intraoperatively with recombinant adenovirus vector containi ...[more]

PMID: 22213093

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Dataset Information

Evaluation of BMP-2 gene-activated muscle grafts for cranial defect repair.

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Evaluation of BMP-2 gene-activated muscle grafts for cranial defect repair.

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