Osterix Overexpression in Mesenchymal Stem Cells Stimulates Healing of Critical-Sized Defects in Murine Calvarial Bone
- 1 October 2007
- journal article
- research article
- Published by Mary Ann Liebert Inc in Tissue Engineering
- Vol. 13 (10), 2431-2440
- https://doi.org/10.1089/ten.2006.0406
Abstract
Osterix (Osx) is a zinc-finger-containing transcription factor that is expressed in osteoblasts of all endochondral and membranous bones. In Osx null mice, osteoblast differentiation is impaired, and bone formation is absent. We hypothesized that overexpression of Osx in bone marrow–derived mesenchymal stem cells (BMSCs) would enhance osteogenic differentiation during bone regeneration in vivo. Overexpression of Osx in mouse BMSCs was achieved using retroviral infection together with a green fluorescent protein (GFP) vector to monitor transduction efficiency and determine the source of regenerative cells in implantation studies. Bone regeneration in vivo was evaluated by implanting BMSCs overexpressing Osx into 4-mm calvarial bone defects in adult mice using type I collagen sponge as a carrier. New bone formation in the defects was quantified using radiological and histological procedures 5 weeks after implantation. The results showed that implantation of Osx-transduced BMSCs resulted in 85% healing of calvarial bone defects as detected using radiological analyses. Histological examination of the implants demonstrated that the Osx-transduced group exhibited amounts of newly formed bone that was five times as high as in a group transduced with the empty vector. Immunohistochemistry for GFP showed positive immunoreaction localized to areas of newly engineered bone in the Osx-transduced group. Immunohistochemistry with antibodies against the extracellular matrix protein bone sialoprotein resulted in strong staining in areas of new bone formation. In addition, the clonal BMSCs showed an osteogenic potential similar to that of primary cultures of BMSCs, suggesting the usefulness of this model in bone tissue engineering. These results indicate that ex vivo gene therapy of Osx is a useful therapeutic approach in regenerating adult bone tissue.Keywords
This publication has 48 references indexed in Scilit:
- Osterix enhances proliferation and osteogenic potential of bone marrow stromal cellsBiochemical and Biophysical Research Communications, 2006
- Expression of Runx2/Cbfa1/Pebp2αA During Angiogenesis in Postnatal Rodent and Fetal Human Orofacial TissuesJournal of Bone and Mineral Research, 2005
- Strong and Rapid Induction of Osteoblast Differentiation by Cbfa1/Til-1 Overexpression for Bone RegenerationPublished by Elsevier BV ,2005
- Differentiation of Osteoblasts from Murine Embryonic Stem Cells by Overexpression of the Transcriptional Factor OsterixTissue Engineering, 2004
- Strategies for Directing the Differentiation of Stem Cells Into the Osteogenic Lineage In VitroJournal of Bone and Mineral Research, 2004
- Replicative Aging and Gene Expression in Long-Term Cultures of Human Bone Marrow Stromal CellsTissue Engineering, 2002
- Series Introduction: Stem cells near the century markJCI Insight, 2000
- Altered Expression of Bone Sialoproteins in Vitamin D–Deficient rBSP2.7Luc Transgenic MiceJournal of Bone and Mineral Research, 1999
- Osteopontin and bone sialoprotein expression in regenerating rat periodontal ligament and alveolar boneThe Anatomical Record, 1996
- The BMP proteins in bone formation and repairTrends in Genetics, 1992