臺灣博碩士論文加值系統

過去研究指出心肌細胞自我再生能力的比例低，因此心臟組織工程修復，細胞療法成為一個有願景的治療。心臟是一個極為複雜的器官且心肌細胞具有方向性，收縮性，和電傳導性。然而複雜的心臟結構在植入後的心肌細胞與宿主組織的限制不只在功能的連結上還包含了長久的治療功效。因此我們利用具生物相容，非降解之具方向性電紡絲補片植入於心臟受損表面，可提供力學支持預防梗塞後心臟病惡化。此外，我們建議將心肌細胞與內皮細胞共同培養能有效提升收縮的一致性和長期的心臟功能表現。總結以上研究，我們提供一個新穎的技術在心臟修復，更重要的是在心肌細胞植入時需考慮心臟具方向性的特性。

Because of the limited regeneration potential of cardiomyocytes, cell-based therapy has emerged as a promising treatment for cardiac repair. Heart is an extremely sophisticated organ with anisotropic structure, contractility and electro-conductivity. Here, we utilized a biocompatible, non-degradable and well-aligned electrospun patch that implantation infarcted myocardium and retard aggravation of post-infarction cardiomyopathy via mechanical supporting. Furthermore, we demonstrated that the aligned patch co-seeded with endothelial cells and neonatal cardiomyocytes significantly improved synchronized contractility and thus long-term cardiac performance. Surprisingly, we found the cardiac function would be even worse after mending of random-aligned patch co-seeded with cells. In summary, the present study provides a novel approach for cardiac repair; importantly, it also raises a valuable awareness that the anisotropic characteristic of the heart should be considered when applying cell transplantation for cardiac repair.

TABLE OF CONTENTS
Abstract I
摘要 II
誌謝 III
TABLE OF CONTENTS V
Index of figures VII
Index of tables VIII
Chapter 1. Introduction 1
1.1 Myocardial infarction 1
1.2 Current therapeutic strategies for MI 1
1.3 Biomaterials for tissue engineering 2
1.4 Cell therapy to regenerate heart function. 3
1.5 Challenge of cardiac patch engineering 4
1.6 Electrospinning apply to tissue engineering 5
Chapter 2. Materials and methods 6
2.1 PAN electrospun patch fabrication 6
2.2 Fiber and cell orientation analyses 6
2.3 Hydrophilic and hydrophobic testing of EP 7
2.4 Cell isolation 7
2.5 Cell culture 8
2.6 Cell viability assay 8
2.7 Cell adhesion assay 9
2.8 Immunocytochemical staining 9
2.9 In vitro atomic force microscopy imaging 10
2.10 In vitro Ca2+ imaging 10
2.11 Rat myocardial infarction model and EP patch implantation 11
2.12 Echocardiography 11
2.13 Hemodynamics 12
2.14 Tissue processing and immunohistochemical staining 12
2.15 Mechanical testing of myocardium 13
2.16 Fluorescent immunohistochemistry 13
2.17 Ex vivo optical mapping 14
2.18 Statistical analysis 14
Chapter3. Results 15
3.1 Cell morphology is regulated by biocompatible anisotropic EP in vitro 15
3.2 Anisotropic feature and EC co-cultivation optimize electro-mechanical function of cardiac construct in vitro 22
3.3 Implantation of EP alone retards pathological remodeling at 2 months after MI 27
3.4 Cell transplantation with aligned EP improves cell engraftment and cardiac function 31
3.5 Cell transplantation with unaligned EP deteriorates cardiac function and induces arrhythmia 36
Chapter 4. Discussion 42
Chapter 5. Conclusion 45
References 46
Index of figures
Figure 1. Schematic diagram of the electrospinning. 5
Figure 2. Cellular morphology is regulated by biocompatible anisotropic electrospun patch in vitro. 21
Figure 3. Electro-mechanical functions of cardiomyocytes were optimized on aEP patch with EC co-cultivation in vitro. 26
Figure 4. Cell transplantation with aligned electrospun patch improves cardiac functions after infarction. 30
Figure 5. Implantation of electrospun patch retards pathological remodeling after infarction via mechanical supporting. 35
Figure 6. Cell transplantation with aEP promotes mechano-electrical integration between graft and host myocardium after infarction. 39
Index of tables
Table 1. Characteristics of biomaterials. 2
Table 2. Hemodynamic parameters at two month after MI. 40
Table 3. Quantification of arrhythmic events. 41

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