High-strength silk protein scaffolds for bone repair

• DOI: 10.1073/pnas.1119474109
• Publication Date: 2012-05-03T04:32:31Z
• Authors: Biman B. Mandal; Ariela Grinberg; Eun Seok Gil; Bruce Panilaitis; David L. Kaplan
• Keywords: Analysis of Variance; Mice, Inbred BALB C; Bone Regeneration; Compressive Strength; Tissue Engineering; Tissue Scaffolds; Silk; Biocompatible Materials; Cell Differentiation; Mesenchymal Stem Cells; 02 engineering and technology; Bombyx; Regenerative Medicine; Biomechanical Phenomena; Mice; Materials Testing; Microscopy, Electron, Scanning; Animals; Female; 0210 nano-technology

Biomaterials for bone tissue regeneration represent a major focus of orthopedic research. However, only handful polymeric biomaterials are utilized today because their failure to address critical issues like compressive strength load-bearing grafts. In this study development high (~13 MPa hydrated state) composite materials is reported, based on silk protein-protein interfacial bonding. Micron-sized fibers (10-600 µm) obtained utilizing alkali hydrolysis were used as reinforcement in compact fiber with tunable strength, surface roughness, and porosity the length included. A combination porosity, scaffold stiffness favored human marrow-derived mesenchymal stem cell differentiation toward bone-like vitro biochemical gene expression markers. Further, minimal vivo immunomodulatory responses suggested compatibility fabricated silk-fiber-reinforced matrices engineering applications.