Osteochondral Interface Tissue Engineering Using Macroscopic Gradients of Bioactive Signals
- 1k Downloads
Continuous gradients exist at osteochondral interfaces, which may be engineered by applying spatially patterned gradients of biological cues. In the present study, a protein-loaded microsphere-based scaffold fabrication strategy was applied to achieve spatially and temporally controlled delivery of bioactive signals in three-dimensional (3D) tissue engineering scaffolds. Bone morphogenetic protein-2 and transforming growth factor-β1-loaded poly(d,l-lactic-co-glycolic acid) microspheres were utilized with a gradient scaffold fabrication technology to produce microsphere-based scaffolds containing opposing gradients of these signals. Constructs were then seeded with human bone marrow stromal cells (hBMSCs) or human umbilical cord mesenchymal stromal cells (hUCMSCs), and osteochondral tissue regeneration was assessed in gradient scaffolds and compared to multiple control groups. Following a 6-week cell culture, the gradient scaffolds produced regionalized extracellular matrix, and outperformed the blank control scaffolds in cell number, glycosaminoglycan production, collagen content, alkaline phosphatase activity, and in some instances, gene expression of major osteogenic and chondrogenic markers. These results suggest that engineered signal gradients may be beneficial for osteochondral tissue engineering.
KeywordsOsteochondral Interface Gradient Microsphere Umbilical cord stem cells PLGA BMP-2 TGF-β1
The authors would like to express their gratitude to the Arthritis Foundation, the National Institutes of Health (NIH/NIDCR 1 R21 DE017673-01) for their support, to NIGMS/NIH Pharmaceutical Aspects of Biotechnology Training grant (T32-GM008359) for supporting N. H. Dormer, and to Dr. Xinkun Wang of the K.U. Genomics Facility for his guidance in RT–PCR.
- 1.An, Y., and K. Martin. Handbook of Histology Methods for Bone and Cartilage. Humana Press, 2003.Google Scholar
- 17.Eufinger, H., C. Rasche, J. Lehmbrock, M. Wehmoller, S. Weihe, I. Schmitz, C. Schiller, and M. Epple. Performance of functionally graded implants of polylactides and calcium phosphate/calcium carbonate in an ovine model for computer assisted craniectomy and cranioplasty. Biomaterials 28:475–485, 2007.CrossRefPubMedGoogle Scholar
- 33.Lu, L. L., Y. J. Liu, S. G. Yang, Q. J. Zhao, X. Wang, W. Gong, Z. B. Han, Z. S. Xu, Y. X. Lu, D. Liu, Z. Z. Chen, and Z. C. Han. Isolation and characterization of human umbilical cord mesenchymal stem cells with hematopoiesis-supportive function and other potentials. Haematologica 91:1017–1026, 2006.PubMedGoogle Scholar
- 35.Luiz Meirelles, L. M., T. Peltola, P. Kjellin, I. Kangasniemi, F. Currie, M. Andersson, T. Albrektsson, and A. Wennerberg. Effect of hydroxyapatite and titania nanostructures on early in vivo bone response. Clin.Implant Dentist. Rel. Res. 10:245–254, 2008.Google Scholar
- 39.Petrie Aronin, C. E., K. W. Sadik, A. L. Lay, D. B. Rion, S. S. Tholpady, R. C. Ogle, and E. A. Botchwey. Comparative effects of scaffold pore size, pore volume, and total void volume on cranial bone healing patterns using microsphere-based scaffolds. J. Biomed. Mater. Res. A 89:632–641, 2009.PubMedGoogle Scholar
- 42.Ross, F., J. Chappel, J. Alvarez, D. Sander, W. Butler, M. Farach-Carson, K. Mintz, P. Robey, S. Teitelbaum, and D. Cheresh. Interactions between the bone matrix proteins osteopontin and bone sialoprotein and the osteoclast integrin alpha v beta 3 potentiate bone resorption. J. Biol. Chem. 268:9901–9907, 1993.PubMedGoogle Scholar
- 45.Shen, H., X. Hu, F. Yang, J. Bei, and S. Wang. An injectable scaffold: rhBMP-2-loaded poly (lactide-co-glycolide)/hydroxyapatite composite microspheres. Acta Biomater. 2009.Google Scholar
- 48.Singh, M., N. Dormer, J. Salash, J. Christian, D. Moore, C. Berkland, and M. Detamore. Three-dimensional macroscopic scaffolds with a gradient in stiffness for functional regeneration of interfacial tissues. J. Biomed. Mater. Res. A. Available online ahead of print, 2010.Google Scholar
- 50.Spinella-Jaegle, S., S. Roman-Roman, C. Faucheu, F. W. Dunn, S. Kawai, S. Galléa, V. Stiot, A. M. Blanchet, B. Courtois, R. Baron, and G. Rawadi. Opposite effects of bone morphogenetic protein-2 and transforming growth factor-beta1 on osteoblast differentiation. Bone 29:323–330, 2001.CrossRefPubMedGoogle Scholar
- 51.Stokes, D., G. Liu, R. Dharmavaram, and D. Hawkins. Regulation of type-II collagen gene expression during human chondrocyte de-differentiation and recovery of chondrocyte-specific phenotype in culture involves Sry-type high-mobility-group box (SOX) transcription factors. Biochem. J. 360:461–470, 2001.CrossRefPubMedGoogle Scholar
- 56.Wang, L., N. H. Dormer, L. Bonewald, and M. S. Detamore. Osteogenic differentiation of human umbilical cord mesenchymal stromal cells in polyglycolic acid scaffolds. Tissue Eng. A. Available online ahead of print, 2010.Google Scholar