生物功能性外基质3D打印支架与共培养修复髁突软骨缺损及机制的研究

Due to the unique structure and special properties of cartilage, once the cartilage defects or degenerative diseases are difficult to heal，Tissue engineered cartilage has opened up a new idea for this. By using 3D-printed PCL-HA scaffold, this study intended to inoculate the adipose mesenchymal stem cells of transfection TGFβ3 into the PCL scaffold to produce cartilage extracellular matrix which would spread in the PCL-HA scaffold which 3D-printed. Later the adipose mesenchymal stem cells were decellularized and the ECM-PCL-HA scaffold in cartilage extracellular matrix were obtained. The synovial-derived mesenchymal stem cells used in previous studies and the articular chondrocytes were co-cultured in the ECM-PCL-HA stent rich in cartilage extracellular matrix for repairing condylar cartilage defects. The restoration outcomes were evaluated. Innovative step of the study consisted in inoculating the adipose mesenchymal stem cells of transfection TGFβ3 into the 3D-printed PCL-HA scaffold. So far, there haven’t been relevant reports both at home and abroad on the practices that the transfected adipose mesenchymal stem cells are used in vitro to generate cartilage extracellular matrix to spread in PCL-HA scaffold and then the cells are sloughed to get the virus-free ECM-PCL-HA scaffold rich in cartilage extracellular matrix. By doing this study, there can be provided a theoretical basis for the clinical application of extracellular matrix scaffold.

由于软骨独特结构和特殊性质，软骨缺损或退行性病变很难自愈。组织工程化软骨修复为其提供了新的思路。本研究，拟通过3D打印PCL-HA支架材料，将转染TGFβ3的脂肪间充质干细胞接种于PCL-HA支架材料中，使其产生软骨细胞外基质分布于PCL-HA支架中，之后将脂肪间充质干细胞脱去，获得富软骨细胞外基质的ECM-PCL-HA支架材料。将前期研究中使用的滑膜间充质干细胞与关节软骨细胞混合培养于ECM-PCL-HA支架材料中，用于修复髁突软骨缺损，评估修复效果。本研究的创新之处在于利用转染TGFβ3的脂肪间充质干细胞接种于3D打印的PCL-HA中，在体外利用转染后的脂肪间充质干细胞分泌产生软骨细胞外基质分布于PCL-HA支架中，然后将细胞脱去，获得无病毒负载的ECM-PCL-HA支架。最终为细胞外基质支架的临床应用提供理论依据。

关节软骨缺损和退变可由多种因素引起，目前临床上针对该病理改变的治疗方案相对有限。 软骨组织工程是再生医学中修复软骨缺损的一种替代疗法。支架材料被认为是组织工程的骨架；因此，支架材料的选择在治疗结果中起着至关重要的作用。聚己内酯(PCL)-羟基磷灰石(HA)作为骨和软骨组织工程的支架材料，具有无毒、无害的代谢物和良好的物理性能。细胞外基质(ECM)主要由胶原蛋白、蛋白多糖以及大量的生长因子和细胞因子组成，为宿主细胞提供了一个组织特异性的微环境。 脂肪源性干细胞(ADMSCs)是一种多能性干细胞，TGF-β3可使间充质干细胞促进细胞外基质的产生。本研究通过体外和体内实验，阐明了基于ECM-PCL-HA支架材料构建的滑膜间充质干细胞(SMSCs) +软骨细胞+ECM-PCL-HA修复系统具有足够的软骨形成能力和修复作用。ECM-PCL-HA可被定义为一种生物功能支架材料。SMSCs +软骨细胞+ECM-PCL-HA修复系统显示新生软骨与表面以及相邻宿主软骨界面的衔接性良好。此外，新生软骨组织的结构与邻近的一致，因此该生物功能性支架及修复系统可以作为关节软骨缺损修复的首选方案。