Co-culture of microtic chondrocyte with BMSC to generate tissue engineered cartilage.

Due to the lack of an appropriate cell source, external ear reconstruction based on tissue engineering techniques has not yet been translated to clinical applications. It has been reported that the chondrocytes from microtic cartilage can be used for cartilage regeneration. However, in our prior study, we found the passaged microtic chondrocytes became less proliferative and decreased expression of cartilage-specific markers, which would lead to the limited quantity and quality of cells from microtic cartilage to engineer an entire ear. To make full use of these cells, it is important to know whether they can provide the chondrogenic niche to promote the chondrogenesis of BMSCs. In this study, through the co-transplantation of BMSCs with microtic chondrocytes subcutaneously into nude mice, we showed that microtic chondrocytes have the potential to promote ectopic chondrogenesis of BMSCs. These results indicate that the early passage of chondrocytes from the microtic cartilage might have the same potential to promote chondrogenesis of BMSCs as normal chondrocytes. The co-culture of microtic chondrocytes with BMSCs potentially offers a practical approach to autologous ear regeneration.