退化性關節炎(Osteoarthritis)是關節軟骨常見的疾病，由於軟骨組織是無血管、神經及淋巴支配的組織，因此受損的軟骨組織之自我修復能力相當有限。軟骨組織工程的基本概念是將細胞取出，並於適合的基材及環境下進行體外培養後，再植入體內，希望透過這樣的方式，獲得近似於天然的軟骨組織，修補軟骨受損部位。組織工程中所使用的支架，其功能在於提供細胞初期貼附，而支架必需具有生物相容性、生物可降解性及適合的力學特性與表面化學特性，促使細胞生長，進而形成組織。本實驗將從猪隻關節中萃取出軟骨細胞，並使用聚乳酸/甘醇酸((Poly (lactide-co-glycolide), PLGA))作為細胞貼附的支架材料，製作方法則採用三維列印法(three-dimensional printing, 3DP)製模技術與鹽析法(salt leaching)結合的方式製作支架，希望製作出不同的外型、尺寸及通道等巨觀特性及含有內部孔洞的支架，達到符合植入軟骨細胞的條件，最後使用H&E及阿辛藍染色法，觀察細胞植入支架後細胞生長及細胞外基質(GAG及蛋白醣)分泌的情形。結果顯示利用三維列印製模技術所製作的PLGA支架之外形，大致能符合原先模具的設計，且具有高孔洞率。將軟骨細胞植入之後，經由染色結果觀察到軟骨細胞貼附在支架內，且隨著天數增加，細胞增生及胞外基質合成的現象也隨之上升。

Osteoarthritis is a common disease of articular cartilage. Due to the lack of blood vessel, neuron, and lymph in cartilage tissue, the ability of self-repair is limited in damaged cartilage tissue. The fundamental concept of tissue engineering includes cell isolating, cell culturing in vitro, and implanting in vivo. To obtain nearly native articular cartilage tissue and repair the damaged section are currently the main purposes of cartilage tissue engineering. For regeneration of large, complex or structural tissues, scaffolds must possess several structural features providing early cell attachment. The specific characters such as biological compatibility, degradability, and adaptive surface chemical and mechanical properties are important. Degradable polymer, poly(lactide-co-glycolide) (PLGA) was used as scaffold material. Chondrocytes isolated from the cartilage of swine were seeded into the porous PLGA scaffold. Combining the methods of three-dimensional printing (3DP) and salt leaching were used to make porous scaffolds with adjustable geometries, sizes, and channels in this study. The conditions of cell proliferation and the extracellular matrix (ECM) production were further observed by H&E and Alcian blue stain. The results indicated that the shape of PLGA scaffold manufactured by three-dimensional printing could match original design of the mold with high porosity. After seeding chondrocyte, we observed that cell attached on the PLGA scaffold. Moreover, the data also showed that the cell proliferation and ECM production were enhanced with increasing seeding time.

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