Study of Nano-Size Memberane Tube for Tendon to Bone in Anterior Cruciate Ligament Reconstruction

Project title：Study of nano-size memberane tube for tendon to bone in anterior cruciate ligament reconstruction 1st year project: Preparation of nano-size memberane tube and cell activities of periosteum progenitor cells 2nd year project: Evaluation of f nano-size memberane tube enhance tendon-to-bone healing in vitro 3rd year project: Experiment of anterior cruciate ligament reconstruction in rabbits and bio-mechanical analysis ABSTRACT Introduction: The hamstring tendons are often as tendon grafts instead of wounded tendons or ligaments while clinical patients need to perform anterior cruciate ligament reconstruction surgery. However, tendon-bone healing usually takes longer recovery time. Hence, according to clinical requirements, an effective way to enhance hamstring tendon healing in a bone tunnel is doctor's goal. The PHAs (Polyhydroxyalkanoates) are produced from microorganisms and funges as resources when they suffer difficult conditions. The PHAs have been proved to apply to biomedical fields such as vascular patch, neuron conduit and articular cartilage tissue engineering. This study uses electrospinning technologies and tissue engineering technologies to form different nano-size memberane tubes (i.e. PHAs, PHAs-TGF-, PHAs-hydroxyapatite, PHAs-TGF--hydroxyapatite) as artificial periosteum substitute tissue. And possible mechanism of tendon–bone healing by those tubes is estimated. Tendon is put into a nano-size memberane tube containing periosteum progenitor cells to promote anterior cruciate ligament reconstruction. This design is a brief operation to process surgery rapidly, and is an innovating potential method for tendon-bone healing. Aim of the study: The purpose of this study is to develop different nano-size memberane tubes, which formatted by the core technologies including electrospinning and materials complex. Nano-size memberane tubes are utilized for anterior cruciate ligament reconstruction. Histology, immune-histology, bio mechanical analysis will be evaluated in this study. Design of the study: First year: Nano-size memberane tubes are prepared using PHAs, TGF- and hydroxyapatite by electrospinning. To confirm the nano-size memberane tubes can maintain the phenotype of periosteum progenitor cells, an experiment in vitro is estimated. Finally, nano-size memberane tubes are prepared. Second year: Periosteum progenitor cells are seeded into nano-size memberane tubes, and put tendon graft into nano-size memberane tubes ex vivo. And bio-chemical properties, histology and immune-histology are evaluated. Third year: The nano-size memberane tubes containing periosteum progenitor cells will be utilized for anterior cruciate ligament reconstruction in rabbits. The outcome of tendon-bone healing is evaluated by histology, immune-histology, bio mechanical analysis. Clinical relevance: We expect that these ex vivo and pre-clinical rabbit experiments will harvest the important information about tendon–bone healing in a bone tunnel when nano-size memberane tubes are applied to tendon graft for anterior cruciate ligament reconstruction. If it is working, this method is been utilized to promote tendon-bone healing when clinical doctors want to reconstruct cruciate ligament. After that patients can accept recovery training as soon as possible, and return to normal kinetism.