間質幹細胞擁有高度的免疫調節以及再生能力，也因此近幾年來間質幹細胞一直都是細胞治療的主力人選，至今也已有眾多臨床試驗證實間質幹細胞在傷口癒合的過程中有良好的表現。然而間質幹細胞促進傷口的癒合的機制以及怎樣給予細胞才能達到最好的效果還尚未有一個完整的解釋。這份研究中我們提出多種細胞治療傷口貼布好讓細胞可以在治療期間停留在傷口處，這些以明膠為基底的傷口貼布透過3D列印技術可以客製化的製作出各種形狀，以配合各種不同的臨床需求。細胞在這樣的貼布裡面能夠維持活性超過12小時，這樣的保存條件也讓細胞貼布在未來有機會變成一個令人期待的新興產品。

Mesenchymal stem cells (MSCs) have been shown to be potential candidates to cell therapy due to their immunomodulation and regeneration abilities. Lots of clinical trials have reached successful results that MSCs could enhance the wound healing process. However, the mechanism how MSCs affect the process and what is the most efficient way to apply cells to the wound still need to be investigated. Some novel cell-embedded patches are introduced in this study to keep the cells at the wound site. The GelMA-based wound healing patch can be fabricated on customization to any shape to meet the clinical needs through 3D printing technique. Most of the cells could survive for more than 12hrs under proper condition, which made the patch a promising product for clinical use in the near future.

誌謝 i
摘要 ii
Abstract iii
Content iv
Chapter 1 Introduction 1
Chapter 2 Materials and Methods 8
2.1 GelMA fabrication 8
2.2 3D printing material preparation 9
2.3 3D printing 10
2.3.1 3D printer setup 10
2.3.2 line width 11
2.3.3 Logo and customized shape printing 12
2.3.4 3D structure 14
2.3.5 Shape-changing property study 15
2.4 Stem-cell-embedded wound healing patch fabrication 16
2.4.1 Cell culture 16
2.4.2 GelMA film 16
2.4.3 Double-layer hexagon grids patch fabrication 17
2.4.4 In-situ GelMA patch 18
2.4.5 Sandwich-patch 19
2.4.6 Fishbone GelMA chain fabrication 20
2.5 Manufacture of handheld UV LED light source 21
2.6 Cell viability test 23
2.7 GelMA cytotoxicity 24
2.7.1 direct contact sample preparation and MTT assay 24
2.7.2 extract sample preparation and MTT assay 25
2.8 GelMA decomposition test 26
2.8.1 MMP2 inhibitor 26
2.8.2 protease inhibitor cocktail 28
2.9 Animal testing 29
Chapter 3 Results and discussion 30
3.1 3D printing 30
3.1.1 Line width 30
3.1.2 Logo, customized shape, and 3D structure printing 33
3.1.3 Shape-changing property 36
3.2 Stem-cell embedded patch and cell viability 38
3.2.1 GelMA film 38
3.2.2 Double-layer hexagon grids patch 40
3.2.3 In-situ GelMA patch 43
3.2.4 Sandwich patch 45
3.2.5 Fishbone GelMA chain 48
3.2.6 pcMSC maintain high viability in the patches 50
3.3 GelMA cytotoxicity evaluation 51
3.3.1 Sample extract test 51
3.3.2 Raw material direct contact test 53
3.4 GelMA decomposition test 55
3.4.1 MMP2 inhibitor 55
3.4.2 protease inhibitor cocktail 58
3.5 Animal testing 60
Chapter 4 Conclusion 65
Reference 66

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