Development of Muscle Tendon Junction in vitro Using Aligned Electrospun PCL Fibres

The muscle tendon junction (MTJ) transmits the force generated by the muscle to the tendon and ultimately to the bone. Tears and strains commonly occur at the MTJ where regeneration is limited due poor vascularisation and the complexity of the tissue. Currently treatments for a complete MTJ tear are often unsuccessful. The creation of a tissue engineered MTJ would therefore be beneficial in the development of a novel treatment. In this study, aligned electrospun polycaprolactone fibres were fabricated and human myoblasts and tenocytes were cultured on the scaffold. The effect of 10 % cyclic strain and co-culture of myoblasts and tenocytes on the MTJ formation was investigated. The application of strain significantly increased cell elongation, and MTJ marker gene expression. Co-culture of myoblasts and tenocytes with strain induced higher MTJ marker gene expression compared with myoblasts and tenocytes cultured separately. Paxillin and collagen 22, naturally found in the MTJ, were also produced when cells were combined and grown in a 10 % strain environment. For the first time these results showed that the combination of the strain and co-culture of myoblasts and tenocytes promotes gene expression and production of proteins that are found in the MTJ.