Chinese researchers have developed injectable biomaterials
|29.9.2020||Posted by tactical33 under Advertising & Marketing|
The meniscus is an important tissue in the knee joint to protect joint stability. But it lacks self-healing ability, and is difficult to repair by itself after injury. Meniscus injury repair is one of the difficult problems in clinical treatment, especially the repair of meniscus white area injury makes clinicians helpless. At present, synthetic materials are mostly used for meniscus repair, but the biocompatibility of synthetic materials is insufficient, and the therapeutic effect on meniscus injury is poor. Therefore, it is urgent to develop materials with high biocompatibility and tissue-specific biological activity for clinical use.
Recently, Yu Yin’s team at the Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, published a research article entitled “Injectable ECM hydrogel for delivery of BMSCs enabled full-thickness meniscus repair in an orthotopic rat model” in Bioactive Materials. In this study, a tissue-specific extracellular matrix (ECM) was obtained by decellularization of porcine meniscus, and it was prepared into an injectable hydrogel for loading bone marrow stem cells (BMSCs) to form a living biomaterial. It has been found that the ECM can promote chondrogenic differentiation of BMSCs; injection of this ECM-loaded BMSCs into the meniscus injury can repair the meniscus injury and inhibit joint degeneration. This study investigated its biocompatibility and chondrogenic properties, and evaluated its repair of meniscal injury and joint protection, which has important clinical significance for meniscal repair.
Inspired by bionics, a tissue-specific extracellular matrix (ECM) was fabricated by decellularization of the medial third of the tissue (white area) of the porcine meniscus and prepared into an injectable hydrogel, which was then loaded with bone marrow stem cells (BMSCs) to form a bioactive intravital gel material for meniscus injury repair. Then in vitro three-dimensional culture of tissue-specific ECM combined with BMSCs was done, and the ECM was found to have excellent biocompatibility and chondrogenic induction ability. After 21 days of culture in vitro, it was found that the morphology and structure of the complex of ECM and BMSCs were closer to normal meniscus tissue, indicating that the ECM is more conducive to the repair of meniscus damage.
Researchers cultured tissue-specific ECM combined with BMSCs in vitro for one week and then placed them on the back of SD rats. Four weeks later, the complex was removed for histological staining. The results showed that a large number of specific markers of cartilage „cartilage pits“ appeared in this tissue, and safranin staining and toluidine blue staining showed strong positive. The research team then made a SD rat model of meniscus injury in the full thickness of the white area of the meniscus. The tissue-specific ECM loaded with BMSCs was injected into the injury site of the model meniscus. Two months later, it was found that the living biomaterial can promote the repair of the meniscus, while protecting the joints, inhibiting calcium loss and osteoarthritis
In this study, tissue-specific ECM was used to load bone marrow stem cells to form injectable intravital hydrogel, and its therapeutic effect in the animal model of full-thickness meniscus injury and the function of protecting the joint from osteoarthritis were studied. The experimental process lasted for two and a half years, overcoming the difficulties in the animal experimental process. The meniscus injury model was constructed by minimally invasive surgery in mice under a microscope, ensuring the accuracy of the experimental model and providing a new idea for the treatment of clinical meniscus injury. It is a beneficial attempt of injectable biomaterials in the application of regenerative medicine.