Chondrogenic differentiation of human adipose tissue-derived stem cells on PLCL/fibrin hybrid scaffolds

In cartilage tissue engineering, choosing on an appropriate cell source and a scaffold for cartilaginous tissue formation seriously influences the clinical application of an engineered cartilage. The purpose of this study is to investigate chondrogenic differentiation of human adipose tissue-derived stromal cells(hASCs) by hybridizing of fibrin gels for mimicking 3-dimensional environments of native cartilage and a poly(L-lactide-co-ε-caprolactone) (PLCL) scaffold. PLCL scaffolds with 85% porosity and 300-500 μm pore size were fabricated by a gel-pressing method. For examining chondrogenic differentiation of hASCs, cells were mixed with 0.5% fibrin solutions and subsequently they were seeded onto PLCL scaffolds. After that, cell-scaffold constructs were implanted subcutaneously in nude mice for up to 8 weeks. Specimens were harvested after 8 weeks and analyzed. From in vivo studies, the constructs used with fibrin-PLCL hybrid scaffolds showed more depositions of cartilage-specific ECM components, such as GAGs and collagen type II, as compared to the constructs used with PLCL scaffolds alone. Furthermore, the constructs seeded with hASCs that were induced to chondrogenesis in vitro prior to implantation improved cartilage matrix deposition as compare to the constructs seeded with non-induced hASCs. These results indicated that the use of the fibrin gels-PLCL hybrid scaffold could enhance chondrogenic differentiation of hASCs and cartilaginous tissue formation. Also, the induction for chondrogenesis of hASCs prior to implantation in vitro could affect cartilaginous tissue formation in vivo. In conclusion, the hybrid system which was fabricated with the inoculation of ASCs and fibrin gels onto a PLCL scaffold could be a meaningful system in cartilage tissue engineering.