Int J Med Sci 2019; 16(4):567-575. doi:10.7150/ijms.30801 This issue Cite
Research Paper
1. Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Stomatological Hospital of Chongqing Medical University, Chongqing 401147, P.R. China
2. Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education College of Stomatology, College of Stomatology, Chongqing Medical University, Chongqing 400016, P.R. China
*These authors contributed equally to the work.
Bone tissue engineering requires a combination of cells, efficient biochemical and physicochemical factors, and biocompatible scaffolds. In this study, we evaluated the potential use of injectable Matrigel as a scaffold for the delivery of rat dental follicle stem/precursor cells (rDFSCs) transduced by bone morphogenetic protein (BMP) 9 to enhance osteogenic differentiation in vitro and promote ectopic bone formation in vivo. Recombinant adenovirus was used to overexpress BMP9 in rDFSCs. Alkaline phosphatase activity was measured using a histochemical staining assay and a chemiluminescence assay kit. Quantitative real-time polymerase chain reaction was used to determine mRNA expression levels of bone-related genes including distal-less homeobox 5 (DLX5), osteopontin (OPN), osterix (Osx), and runt-related transcription factor 2 (Runx2). Matrix mineralization was examined by Alizarin Red S staining. rDFSCs proliferation was analyzed using the Cell Counting Kit-8 assay. Subcutaneous implantation of rDFSCs-containing Matrigel scaffolds was used, and micro-computed tomography analysis, histological evaluation, and trichrome staining of implants extracted at 6 weeks were performed. We found that BMP9 enhanced alkaline phosphatase activity and mineralization in rDFSCs. The expression of bone-related genes (DLX5, OPN, Osx, and Runx2) was also increased as a result of BMP9 stimulation. Micro-computed tomography analysis and histological evaluation revealed that the bone masses retrieved from BMP9-overexpressing rDFSCs were significantly more pronounced in those with than in those without Matrigel. Our results suggest that BMP9 effectively promote osteogenic differentiation of rDFSCs, and Matrigel facilitate BMP9-induced osteogenesis of rDFSCs in vivo.
Keywords: matrigel, BMP9, rDFSCs, bone formation