關節軟骨一旦受損便難以自行修復，故至今關節軟骨的治療面臨很大的挑戰。目前臨床上的治療仍有很多問題存在，例如: 骨軟骨微創修復後之新生組織多為纖維軟骨、組織與填補材料之間的整合性不高以及在體外培養時軟骨細胞的去分化等等，而組織工程則希望可以結合細胞及生物支架為軟骨修復治療方面提供一種替代方案，其中生物支架的結構與其化學性質皆可能影響組織之修復。故本實驗期許結合小孔洞及大孔洞的聚乳酸-甘醇酸生物支架可分別使軟骨及硬骨細胞貼附；同時結合乙二胺及酪胺兩種表面處理的方式促進雙層聚乳酸聚甘醇酸生物支架與組織之間的整合。
本研究第一部分成功利用鹽析法製備直徑3 mm 、高度3 mm、孔洞率89%之雙層聚乳酸-甘醇酸生物支架，而上下層孔徑大小分別為100 μm及300 μm，其目的為在培養軟骨細胞過程維持其原始型態。利用冷凍切片及電子顯微鏡之結果皆可初步得知軟骨細胞在5天的培養下可維持其原始型態。
本研究第二部分主要是將未處理之控制組、乙二胺及酪胺表面處理後之雙層聚乳酸-甘醇酸生物支架組別置入直徑8 mm之豬之骨軟骨組織中直徑3 mm之缺陷部位共培養4周後，觀察表面處理過後生物支架是否能促進支架與組織之間的整合性。從機械測試的結果可得知利用酪胺進行前處理的組別與豬骨軟骨組織在體外共培養後黏附剪力與其他組存在顯著性差異，另外自免疫化學組織染色之結果中可得知酪胺前處理之組別其修復後之新生軟骨表現多為透明軟骨。
整體而言，以體外培養之結果，100 μm孔洞大小之PLGA生物支架可有效維持軟骨細胞之原始型態，另外利用酪胺進行前處理的生物支架在與組織整合方面有其效用。

Repairing damaged articular cartilage is challenging since its limited self-repair ability of hyaline cartilage. Nowadays, several treatments are available for repairing damaged cartilage. However, most of them still remain controversial for numerous problems. For instance, the repaired tissues by microfracture turned into fibrous cartilage. And autologous osteochondral plug repairmen exists some issue about integration with native tissue. Also, chondrocytes in vitro monolayer culture will lead to dedifferentiation then lose its original phenotype. Tissue engineering cartilage provides alternative approach to provide hope for cartilage repairing. The structure and property of scaffold can determine the outcome of tissue regeneration. This study proposes to use small and large pore size of PLGA scaffold to maintain chondrocytes and osteoblasts respectively; and surface treatment on scaffold with ethylenediamine or tyramine to assist scaffold and tissue integration.
In part I study, diameter 3 mm, height 3 mm PLGA scaffold was fabricated by salt leaching method. The biphasic PLGA scaffold with 89% porosity and 300 μm and 100 μm pore size for bottom and top layer respectively, was fabricated for chondrocytes culture. The results from histology and SEM show the chondrocytes remain its rounded phenotype appearance in 5-day culture in small pore size scaffold. From cell membrane label fluorescent and SEM results, both examine methods prove that after 5 days culture in small pore size upper layer scaffold, chondrocytes can maintain its rounded phenotype.
In part II study, biphasic scaffolds treated with ethylenediamine or tyramine and no treatment control group were pressed into 8 mm porcine osteochondral plug with defect 3 mm diameter and 3 mm depth for 4 weeks to test the integration of these scaffolds. The push out test was practiced to confirm the adhesive stress between scaffold and porcine cartilage. And this result shows tyramine treated group has the highest adhesive stress. On the other hand, from immunohistochemical stain, tyramine treated group appears better hyaline cartilage regeneration.
This study shows small pore size scaffold can successfully maintain chondrocytes phenotype, and surface tyramine treated PLGA scaffold can assist its integration with surrounding tissue.

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