Influence of TECK on chondrocyte differentiation

Nowadays, cartilage repair is a worldwide centre of interest due to the low potential of cartilage to heal spontaneously and the increasing number of patients around the world. One of the techniques to treat cartilage defect is to use autologous human serum in cell-free implants to recruit chondrocytes. However, the serum is variable in its quality and therefore the chemokine TECK might be used as a reliable bioactive pharmaceutical component to recruit chondrocytes in cartilage regeneration techniques. In this study, the influence of the chemokine TECK on chondrocytes re-differentiation was studied during early chondrogenesis. So, high-density pellets were formed from three donors and cultivated for two and four days in three different concentrations of TECK, 0 [nM], 10 [nM] and 1000 [nM]. The high-density pellets were compared and analyzed at the protein and mRNA levels. Indeed, proteoglycans and type II collagen were stained to reveal the production of these two essential markers of chondrogenesis and RT-PCR was performed to evaluate the mRNA expression levels of various genes, type II collagen, type IX collagen, aggrecan, Sox 9, COMP, MMP 13 and Timp 1-2. It resulted that chondrocytes of two out of three donors showed a potential to re-differentatiate. In fact, these two donors increased their productions of proteolycans and type II collagen between day two and day four, a lapse of time considered as early chondrogenesis. These results were confirmed by the mRNA expression levels, which indicated increases of the expression levels in type II collagen, type IX collagen, aggrecan and Sox 9. Thus, the chemokine TECK showed no evidence that it modified the behaviours of chondrocytes in high-density pellets during the first four days. So, TECK might be a reliable bioactive pharmaceutical component to recruit chondrocytes in order to regenerate cartilage in the future