Growth factor-free salt-leached silk scaffolds for differentiating endothelial cells

Abstract

Recently, controllable kinetic assembly has been introduced into the salt-leaching process with silk proteins to form scaffolds, which achieved improvement in tuning the micro-structural and mechanical properties. Here, more control of the kinetic assembly of silk in the process was integrated into the salt-leaching process, resulting in significant mechanical modification of the scaffolds generated. Both glycerol addition and treatment to concentrate the protein were used to tune the hydrophilic interactions during aqueous solution processing and to reduce beta-sheet formation during the salt-leaching process. These new scaffolds showed gradient changes in the elastic modulus in the range of 0.9 to 7.9 kPa. Bone marrow mesenchymal stem cells grew well and showed endothelial differentiation behavior on the scaffolds with optimized stiffness. These results indicated that the introduction of the silk kinetic assembly provides an additional option for the control of porous silk scaffold properties.