Research and Development for Fabrication of 3D-structured Tissue-engineered Cartilage through Nino-molecular Technologies

软骨是运动组织和支持组织的主要组成部分。由于软骨组织遭受创伤、老化疾病、炎症和先天性异常等各种疾病和紊乱，软骨的再生和重建是骨科领域的重要课题。虽然软骨组织工程作为自体软骨细胞移植逐渐盛行，但对于骨关节炎终末期、先天性软骨异常等较为严重的软骨疾病，为了扩大软骨组织工程的适应症范围，还需要3d结构的组织工程软骨。除此之外，纳米技术已经取得了显著的进展，可以将物质控制在小于1微米的尺度上，并制造出多能高分子。在本项目中，我们试图将纳米技术应用于体外软骨细胞增殖和3d结构组织工程软骨的制造。为了防止培养的软骨细胞去分化，3D培养是有用的。然而，软骨细胞在三维条件下的增殖培养尚未见报道。在本项目中，我们尝试使用中空纤维来制作三维增殖培养系统。为了解决软骨细胞在增殖培养过程中去分化的问题，我们还研究了可溶性因子的组合对去分化软骨细胞的再分化作用。结果表明，BMP-2、胰岛素和T3联合可诱导理想的再分化。此外，我们还研究了新型材料，包括合成肽无交叉污染风险的支架和用于基因转染的功能胶束。这些结果将为软骨组织工程的临床应用提供有用的信息。

Cartilage is a major component that consists of motor and supportive tissues. Because the cartilaginous tissues suffer from various diseases and disorders including trauma, ageing diseases, inflammation and congenital anomaly, the regeneration and reconstruction of cartilage is the most important topic in the orthopaedic fields. Although the cartilage tissue engineering has gradually prevailed as autologous chondrocyte transplantation, 3D-structured tissue-engineered cartilage are needed in order to broaden the indication range of the cartilage tissue engineering for the more severe cartilage diseases such as end stage of osteoarthritis and congenital anomaly of cartilage. Otherwise, the nanotechnology has remarkably progressed, which can control the matter on a scale smaller than 1 micrometer and fabricate multipotent prolymers. In the present project, we attempted to apply the nanotechnology for the proliferation of chondrocytes in vitro and the fabrication of 3D-structured tissue-engineered cartilage.In order to prevent dedifferentiation of cultured chondrocytes, 3D culture is useful. However, the proliferation culture of chondrocytes under 3D condition had not been reported. In the present project, we attempted to use hollow fibers for the purpose of making the 3D proliferation culture system. We also investigated the combination of soluble factors that redifferentiate dedifferentiated chondrocytes, in order to solve the problem that the chondrocytes are dedifferentiated during the proliferation culture. As results, the combination of BMP-2, insulin and T3 was revealed to induce ideal redifferentiation. Moreover, we examined the novel materials including the scaffolds which synthetic peptides possess no risk of cross-contamination and the functional micelles for gene transfection.These results would provide useful information for the clinical application of cartilage tissue engineering.