title: Osteogenic differentiation as a result of BMP-2 plasmid DNA based gene therapy in vitro and in vivo.
abstract: Bone regeneration is one of the major focus points in the field of regenerative medicine. A well-known stimulus of bone formation is bone morphogenetic protein-2 (BMP-2), which has already been extensively used in clinical applications. We investigated the possibility of achieving osteogenic differentiation both in vitro and in vivo as a result of prolonged presence of BMP-2 using plasmid DNA-based gene therapy. By delivering BMP-2 cDNA in an alginate hydrogel, a versatile formulation is developed. High transfection efficiencies of up to 95% were obtained in both human multipotent stromal cells (MSCs) and MG-63 cells using naked DNA in vitro. Over a period of 5 weeks, an increasing amount of biologically active BMP-2 was released from the cells and remained present in the gel. In vivo, transfected cells were found after both two and six weeks implantation in naked mice, even in groups without seeded cells, thus indicating in vivo transfection of endogenous cells. The protein levels were effective in inducing osteogenic differentiation in vitro, as seen by elevated alkaline phosphatase (ALP) production and in vivo, as demonstrated by the production of collagen I and osteocalcin in a mineralised alginate matrix. We conclude that BMP-2 cDNA incorporated in alginate hydrogel appears to be a promising new strategy for minimal-invasive delivery of growth factors in bone regeneration.
authors.affiliation: Department of Orthopaedics, Utrecht, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Wegman
authors.forename: A
authors.initials: A
authors.lastname: Bijenhof
authors.forename: L
authors.initials: L
authors.lastname: Schuijff
authors.forename: F C
authors.initials: FC
authors.lastname: Oner
authors.forename: W J A
authors.initials: WJ
authors.lastname: Dhert
authors.forename: J
authors.initials: J
authors.lastname: Alblas
mesh_terms: D000464:Alginates / Q000494:pharmacology; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000235:genetics* / Q000627:therapeutic use*; D002113:Calcification, Physiologic / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D045744:Cell Line, Tumor; D004247:DNA / Q000235:genetics*; D005434:Flow Cytometry; D015316:Genetic Therapy; D020723:Glucuronic Acid / Q000494:pharmacology; D006041:Goats; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006603:Hexuronic Acids / Q000494:pharmacology; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D051379:Mice; D008819:Mice, Nude; D010012:Osteogenesis / Q000187:drug effects; D019899:Paracrine Communication / Q000187:drug effects; D010957:Plasmids / Q000235:genetics*; D019919:Prosthesis Implantation; D014162:Transfection
chemical_list: D000464:Alginates; D055396:Bone Morphogenetic Protein 2; D006603:Hexuronic Acids; D049452:Green Fluorescent Proteins; D020723:Glucuronic Acid; D004247:DNA; D000469:Alkaline Phosphatase