title: Promising efficacy of Escherichia coli recombinant human bone morphogenetic protein-2 in collagen sponge for ectopic and orthotopic bone formation and comparison with mammalian cell recombinant human bone morphogenetic protein-2.
abstract: Nonglycosylated recombinant human bone morphogenetic protein (rhBMP)-2 prepared in Escherichia coli (E. coli rhBMP-2) has recently been considered as an alternative to mammalian cell rhBMP-2. However, its clinical use is still limited owing to lack of evidence for osteogenic activity comparable with that of mammalian cell rhBMP-2 via microcomputed tomography-based analysis. Therefore, this study aimed to evaluate the ability of E. coli rhBMP-2 in absorbable collagen sponge to form ectopic and orthotopic bone and to compare it to that of mammalian rhBMP-2. In vitro investigation was performed to study osteoblast differentiation of human mesenchymal stromal cells. Both types of rhBMP-2 enhanced proliferation, alkaline phosphatase activity, and matrix mineralization of human mesenchymal stromal cells at similar levels. Similar tendencies were observed in microcomputed tomography analysis, which determined bone volume, fractional bone volume, trabecular thickness, trabecular separation, bone mineral density, and other characteristics. Histology from an in vivo osteoinductivity test and from a rat calvarial defect model demonstrated a dose-dependent increase in local bone formation. The E. coli rhBMP-2 group (5 μg) not only induced complete regeneration of an 8-mm critical-sized defect at 4 weeks, but also led to new bone with the same bone mineral density as normal bone at 8 weeks, with the same efficiency as that of mammalian cell rhBMP-2 (5 μg). These uniformly favorable results provide evidence that the osteogenic activity of E. coli rhBMP-2 is not inferior to that of mammalian cell rhBMP-2 despite its low solubility and lack of gylcosylation. These results suggest that the application of E. coli rhBMP-2 in absorbable collagen sponge may be a promising equivalent to mammalian cell rhBMP-2 in bone tissue engineering.
authors.affiliation: Dental Research Institute, Seoul National University, Seoul, Republic of Korea.
authors.forename: In Sook
authors.initials: IS
authors.lastname: Kim
authors.forename: Eui Nam
authors.initials: EN
authors.lastname: Lee
authors.forename: Tae Hyung
authors.initials: TH
authors.lastname: Cho
authors.forename: Yun Mi
authors.initials: YM
authors.lastname: Song
authors.forename: Soon Jung
authors.initials: SJ
authors.lastname: Hwang
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Oh
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Park
authors.forename: Tai Young
authors.initials: TY
authors.lastname: Koo
authors.forename: Young-Kwon
authors.initials: YK
authors.lastname: Seo
mesh_terms: D000818:Animals; D001846:Bone Development / Q000187:drug effects / Q000502:physiology*; D055396:Bone Morphogenetic Protein 2 / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology*; D018786:Bone Substitutes / Q000627:therapeutic use*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D015202:Protein Engineering / Q000379:methods; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D012887:Skull Fractures / Q000473:pathology / Q000601:surgery*; D013045:Species Specificity; D054457:Tissue Scaffolds; D016896:Treatment Outcome
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D018786:Bone Substitutes; D011994:Recombinant Proteins