Title: Osteogenic differentiation as a result of BMP-2 plasmid DNA based gene therapy in vitro and in vivo

Author: F Wegman, A Bijenhof, L Schuijff, FC Öner, WJA Dhert, J Alblas

Address: Department of Orthopaedics, Room G05.228, University Medical Center Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands

E-mail: J.Alblas at umcutrecht.nl

Key Words: Bone morphogenetic protein (BMP), osteogenic differentiation, multipotent stromal cells (MSC), transfection, hydrogel, bone graft, bone regeneration.

Publication date: March 15th 2011

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.

Article download: Pages 230-242 (PDF file)
DOI: 10.22203/eCM.v021a18