A 3D biodegradable protein based matrix for cartilage tissue engineering and stem cell differentiation to cartilage

A protein based 3D porous scaffold is fabricated by blending gelatin and albumin. The biomimetic biodegradable gelatin, promoted good cell adhesion and its hydrophilic nature enabled absorption of culture media. Albumin is proposed to serve as a nontoxic foaming agent and also helped to attain a hydrophobic-hydrophilic balance. The hydrophobic-hydrophilic balance and appropriate crosslinking of the scaffold avoided extensive swelling, as well as retained the stability of scaffold in culture medium for long period. The scaffold is found to be highly porous with open interconnected pores. The adequate swelling and mechanical property of the scaffold helped to withstand the loads imparted by the cells during in vitro culture. The scaffold served as a nontoxic material to monolayer of fibroblast cells and is found to be cell compatible. The suitability of scaffold for chondrocyte culture and stem cell differentiation to chondrocytes is further explored in this work. The scaffold provided appropriate environment for chondrocyte culture, resulting in deposition of cartilage specific matrix molecules that completely masked the pores of the porous scaffold. The scaffold promoted the proliferation and differentiation of mesenchymal stem cells to chondrocytes in presence of growth factors. The transforming growth factor, TGFbeta3 promoted better chondrogenic differentiation than its isoform TGFbeta1 in this scaffold.