The influence of elasticity and surface roughness on myogenic and osteogenic-differentiation of cells on silk-elastin biomaterials.

Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA.
Biomaterials (Impact Factor: 8.31). 08/2011; 32(34):8979-89. DOI: 10.1016/j.biomaterials.2011.08.037
Source: PubMed

ABSTRACT The interactions of C2C12 myoblasts and human bone marrow stem cells (hMSCs) with silk-tropoelastin biomaterials, and the capacity of each to promote attachment, proliferation, and either myogenic- or osteogenic-differentiation were investigated. Temperature-controlled water vapor annealing was used to control beta-sheet crystal formation to generate insoluble silk-tropoelastin biomaterial matrices at defined ratios of the two proteins. These ratios controlled surface roughness and micro/nano-scale topological patterns, and elastic modulus, stiffness, yield stress, and tensile strength. A combination of low surface roughness and high stiffness in the silk-tropoelastin materials promoted proliferation and myogenic-differentiation of C2C12 cells. In contrast, high surface roughness with micro/nano-scale surface patterns was favored by hMSCs. Increasing the content of human tropoelastin in the silk-tropoelastin materials enhanced the proliferation and osteogenic-differentiation of hMSCs. We conclude that the silk-tropoelastin composition facilitates fine tuning of the growth and differentiation of these cells.

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