Marrow stromal cells (MSCs) include stem cells capable of forming all mesenchymal tissues, including bone. However, before MSCs can be successfully used in regeneration procedures, methods must be developed to stimulate their differentiation selectively to osteoblasts. Runx2, a bone-specific transcription factor, is known to stimulate osteoblast differentiation. In the present study, we tested the hypothesis that Runx2 gene therapy can be used to heal a critical-sized defect in mouse calvaria. Runx2-engineered MSCs displayed enhanced osteogenic potential and osteoblast-specific gene expression in vitro and in vivo. Runx2-expressing cells also dramatically enhanced the healing of critical-sized calvarial defects and increased both bone volume fraction and bone mineral density. These studies provide a novel route for enhancing osteogenesis that may have future therapeutic applications for craniofacial bone regeneration.
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References
1.
Asahara T, Kalka C, Isner JM -2000-. Stem cell therapy and gene transfer for regeneration. Gene Ther7:451–457.
2.
Bianco P, Riminucci M, Gronthos S, Robey PG -2001-. Bone marrow stromal stem cells: nature, biology, and potential applications. Stem Cells19:180–192.
3.
Blyth K, Terry A, Mackay N, Vaillant F, Bell M, Cameron ER, et al. -2001-. Runx2: a novel oncogenic effector revealed by in vivo complementation and retroviral tagging. Oncogene20:295–302.
4.
Boyan BD, Hummert TW, Dean DD, Schwartz Z -1996-. Role of material surfaces in regulating bone and cartilage cell response. Biomaterials17:137–146.
5.
Bruder SP, Fox BS -1999-. Tissue engineering of bone. Cell based strategies. Clin Orthop Relat Res367-Suppl-:S68–S83.
6.
Byers BA, Garcia AJ -2004-. Exogenous Runx2 expression enhances in vitro osteoblastic differentiation and mineralization in primary bone marrow stromal cells. Tissue Eng10:1623–1632.
7.
Byers BA, Guldberg RE, Hutmacher DW, Garcia AJ -2006-. Effects of Runx2 genetic engineering and in vitro maturation of tissue-engineered constructs on the repair of critical size bone defects. J Biomed Mater Res A76:646–655.
8.
Derubeis AR, Cancedda R -2004-. Bone marrow stromal cells -BMSCs- in bone engineering: limitations and recent advances. Ann Biomed Eng32:160–165.
9.
Geoffroy V, Kneissel M, Fournier B, Boyde A, Matthias P -2002-. High bone resorption in adult aging transgenic mice overexpressing cbfa1/runx2 in cells of the osteoblastic lineage. Mol Cell Biol22:6222–6233.
10.
Kojima H, Uemura T -2005-. Strong and rapid induction of osteoblast differentiation by Cbfa1/Til-1 overexpression for bone regeneration. J Biol Chem280:2944–2953.
11.
Krebsbach PH, Kuznetsov SA, Satomura K, Emmons RV, Rowe DW, Robey PG -1997-. Bone formation in vivo: comparison of osteogenesis by transplanted mouse and human marrow stromal fibroblasts. Transplantation63:1059–1069.
12.
Krebsbach PH, Mankani MH, Satomura K, Kuznetsov SA, Robey PG -1998-. Repair of craniotomy defects using bone marrow stromal cells. Transplantation66:1272–1278.
13.
Krebsbach PH, Kuznetsov SA, Bianco P, Robey PG -1999-. Bone marrow stromal cells: characterization and clinical application. Crit Rev Oral Biol Med10:165–181.
14.
Liu W, Toyosawa S, Furuichi T, Kanatani N, Yoshida C, Liu Y, et al. -2001-. Overexpression of Cbfa1 in osteoblasts inhibits osteoblast maturation and causes osteopenia with multiple fractures. J Cell Biol155:157–166.
15.
Lynch MP, Stein JL, Stein GS, Lian JB -1995-. The influence of type I collagen on the development and maintenance of the osteoblast phenotype in primary and passaged rat calvarial osteoblasts: modification of expression of genes supporting cell growth, adhesion, and extracellular matrix mineralization. Exp Cell Res216:35–45.
16.
Muschler GF, Nitto H, Boehm CA, Easley KA -2001-. Age- and gender-related changes in the cellularity of human bone marrow and the prevalence of osteoblastic progenitors. J Orthop Res19:117–125.
17.
Noguchi P -2003-. Risks and benefits of gene therapy. N Engl J Med348:193–194.
18.
Oreffo RO, Bord S, Triffitt JT -1998-. Skeletal progenitor cells and ageing human populations. Clin Sci -Lond-94:549–555.
19.
Osyczka AM, Diefenderfer DL, Bhargave G, Leboy PS -2004-. Different effects of BMP-2 on marrow stromal cells from human and rat bone. Cells Tissues Organs176:109–119.
20.
Park J, Ries J, Gelse K, Kloss F, von der Mark K, Wiltfang J, et al. -2003-. Bone regeneration in critical size defects by cell-mediated BMP-2 gene transfer: a comparison of adenoviral vectors and liposomes. Gene Ther10:1089–1098.
21.
Rose FR, Oreffo RO -2002-. Bone tissue engineering: hope vs hype. Biochem Biophys Res Commun292:1–7.
22.
St George JA -2003-. Gene therapy progress and prospects: adenoviral vectors. Gene Ther10:1135–1141.
23.
Takahashi Y, Yamamoto M, Tabata Y -2005-. Osteogenic differentiation of mesenchymal stem cells in biodegradable sponges composed of gelatin and beta-tricalcium phosphate. Biomaterials26:3587–3596.
24.
Tsuda H, Wada T, Ito Y, Uchida H, Dehari H, Nakamura K, et al. -2003-. Efficient BMP2 gene transfer and bone formation of mesenchymal stem cells by a fiber-mutant adenoviral vector. Mol Ther7:354–365.
25.
Turgeman G, Pittman DD, Muller R, Kurkalli BG, Zhou S, Pelled G, et al. -2001-. Engineered human mesenchymal stem cells: a novel platform for skeletal cell mediated gene therapy. J Gene Med3:240–251.
26.
Warren SM, Fong KD, Chen CM, Loboa EG, Cowan CM, Lorenz HP, et al. -2003a-. Tools and techniques for craniofacial tissue engineering. Tissue Eng9:187–200.
27.
Warren SM, Greenwald JA, Nacamuli RP, Fong KD, Song HJ, Fang TD, et al. -2003b-. Regional dura mater differentially regulates osteoblast gene expression. J Craniofac Surg14:363–370.
28.
Xiao G, Wang D, Benson MD, Karsenty G, Franceschi RT -1998-. Role of the alpha2-integrin in osteoblast-specific gene expression and activation of the Osf2 transcription factor. J Biol Chem273:32988–32994.
29.
Yang S, Wei D, Wang D, Phimphilai M, Krebsbach PH, Franceschi RT -2003-. in vitro and in vivo synergistic interactions between the Runx2/Cbfa1 transcription factor and bone morphogenetic protein-2 in stimulating osteoblast differentiation. J Bone Miner Res18:705–715.
30.
Zhao M, Zhao Z, Koh JT, Jin T, Franceschi RT -2005a-. Combinatorial gene therapy for bone regeneration: cooperative interactions between adenovirus vectors expressing bone morphogenetic proteins 2, 4, and 7. J Cell Biochem95:1–16.
31.
Zhao Z, Zhao M, Xiao G, Franceschi RT -2005b-. Gene transfer of the Runx2 transcription factor enhances osteogenic activity of bone marrow stromal cells in vitro and in vivo. Mol Ther12:247–253.
