An injectable cellulose-based hydrogel for the transfer of autologous nasal chondrocytes in articular cartilage defects.

Articular cartilage has a low capacity for spontaneous repair. To promote the repair of this tissue, the transfer of autologous chondrocytes using a three-dimensional matrix appears promising. In this context, the aim of the present work was to investigate the potential use of autologous rabbit nasal chondrocytes (RNC) associated with an injectable self-setting cellulose-based hydrogel (Si-HPMC). Firstly, the influence of Si-HPMC on chondrocytic phenotype was investigated by real-time PCR for specific chondrocyte markers (type II collagen and aggrecan) and type I collagen. Thereafter, autologous RNC were amplified in vitro for 4 weeks before transplantation with Si-HPMC into a rabbit articular cartilage defect followed by analysis 6 weeks later. Implants were histologically characterized for the presence of sulfated GAG and type II collagen. Transcripts analysis indicated that dedifferentiated RNC recovered expression of the main chondrocytic markers after in vitro three-dimensional culture within Si-HPMC. Histological analysis of autologous RNC transplanted in an articular cartilage defect revealed the formation of repair tissue with a histological organization similar to that of healthy articular cartilage. In addition, immunohistological analysis of type II collagen suggested that the repair tissue was a hyaline-like cartilage. Si-HPMC hydrogel associated with nasal chondrocytes therefore appears a promising injectable tissue engineering device for the repair of articular cartilage.