Cheuk, Yau Chuk. / Thesis submitted in: Dec 2008. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 132-144). / Abstracts in English and Chinese. / ABSTRACT --- p.i / 論文摘要 --- p.iii / PUBLICATIONS --- p.v / ACKNOWLEDGEMENT --- p.vi / LIST OF ABBREBIVIATIONS --- p.vii / INDEX FOR FIGURES --- p.x / INDEX FOR TABLES --- p.xiv / TABLE OF CONTENTS --- p.xv / Chapter CHAPTER ONE - --- INTRODUCTION / Chapter 1.1 --- "Joint function, structure and biochemistry" / Chapter 1.1.1 --- Function of joint --- p.1 / Chapter 1.1.2 --- Types of cartilage --- p.1 / Chapter 1.1.3 --- Composition and structure of articular cartilage --- p.2 / Chapter 1.1.4 --- The subchondral bone --- p.3 / Chapter 1.1.5 --- Maturation of articular cartilage and subchondral bone --- p.3 / Chapter 1.2 --- Osteochondral defect / Chapter 1.2.1 --- Clinical problem --- p.6 / Chapter 1.2.2 --- Spontaneous repair --- p.7 / Chapter 1.2.3 --- Current treatment strategies --- p.7 / Chapter 1.2.4 --- Limitations of current treatment strategies --- p.8 / Chapter 1.2.5 --- Treatments under development --- p.11 / Chapter 1.2.6 --- Potential and limitations in cell therapies --- p.14 / Chapter 1.3 --- The 3-D scaffold-free cartilage / Chapter 1.3.1 --- Fabrication of scaffold-free cartilage --- p.16 / Chapter 1.3.2 --- Scaffold-free cartilage for chondral / osteochondral defect repair --- p.18 / Chapter 1.3.3 --- Scaffold-free bioengineered chondrocyte pellet from our group --- p.20 / Chapter 1.3.4 --- BCP as a possible treatment for OCD --- p.21 / Chapter 1.4 --- The objectives of the study --- p.22 / Chapter 1.5 --- The study plan / Chapter 1.5.1 --- Design of the study --- p.23 / Chapter 1.5.2 --- Choice of animal model --- p.23 / Chapter 1.5.3 --- Selection of evaluation time points --- p.24 / Chapter 1.5.4 --- Choice and modification of histological scoring system --- p.24 / Chapter CHAPTER TWO - --- METHODOLOGY / Chapter 2.1 --- Preparation of reagents and materials for tissue culture and histology --- p.26 / Chapter 2.2 --- Creation of osteochondral defect model --- p.28 / Chapter 2.3 --- Synthesis of scaffold-free cartilage using 3-D chondrocyte pellet culture / Chapter 2.3.1 --- Isolation of rabbit costal chondrocytes --- p.31 / Chapter 2.3.2 --- Three-dimensional chondrocyte pellet culture --- p.31 / Chapter 2.3.3 --- BrdU labeling for cell fate tracing --- p.32 / Chapter 2.4 --- Further characterization of the 3-D scaffold-free chondrocyte pellet / Chapter 2.4.1 --- Gross appearance --- p.35 / Chapter 2.4.2 --- Cell viability / Chapter 2.4.2.1 --- Alamar blue reduction assay --- p.35 / Chapter 2.4.3 --- Preparation of samples for histology --- p.36 / Chapter 2.4.4 --- General morphology and histomorphology / Chapter 2.4.4.1 --- H&E staining --- p.36 / Chapter 2.4.5 --- Cartilage properties / Chapter 2.4.5.1 --- Safranin O /Fast Green staining --- p.37 / Chapter 2.4.5.2 --- Immunohistochemistry of type II collagen --- p.37 / Chapter 2.4.5.3 --- Immunohistochemistry of type I collagen --- p.38 / Chapter 2.4.6 --- Angiogenic properties / Chapter 2.4.6.1 --- Immunohistochemistry of VEGF --- p.40 / Chapter 2.4.7 --- Osteogenic properties / Chapter 2.4.7.1 --- ALP staining --- p.40 / Chapter 2.5 --- Implantation of scaffold-free cartilage into osteochondral defect model / Chapter 2.5.1 --- Surgical procedures --- p.41 / Chapter 2.5.2 --- Experimental groups --- p.42 / Chapter 2.6 --- Assessment of osteochondral defect healing / Chapter 2.6.1 --- Macroscopic evaluation --- p.43 / Chapter 2.6.2 --- Preparation of samples for histology --- p.43 / Chapter 2.6.3 --- Histology for general morphology / Chapter 2.6.3.1 --- H&E staining --- p.45 / Chapter 2.6.4 --- Histological scoring / Chapter 2.6.4.1 --- Modification of the scoring system --- p.45 / Chapter 2.6.4.2 --- Procedures of scoring and validation --- p.45 / Chapter 2.6.5 --- Cell proliferation / Chapter 2.6.5.1 --- Immunohistochemistry of PCNA --- p.49 / Chapter 2.6.6 --- Cartilage regeneration / Chapter 2.6.6.1 --- Safranin O /Fast Green staining --- p.49 / Chapter 2.6.6.2 --- Immunohistochemistry of type II collagen --- p.49 / Chapter 2.6.6.3 --- Immunohistochemistry of type I collagen --- p.50 / Chapter 2.6.6.4 --- Polarized light microscopy --- p.50 / Chapter 2.6.7 --- Expression of angiogenic factor / Chapter 2.6.7.1 --- Immunohistochemistry of VEGF --- p.50 / Chapter 2.6.8 --- Bone regeneration / Chapter 2.6.8.1 --- μCT analysis --- p.50 / Chapter 2.6.9 --- Histomorphometric analysis of cartilage and bone regeneration --- p.53 / Chapter 2.6.10 --- BrdU detection for cell fate tracing --- p.55 / Chapter 2.6.11 --- Statistical analysis --- p.55 / Chapter CHAPTER THREE - --- RESULTS / Chapter 3.1 --- Further characterization of the 3-D chondrocyte pellet culture / Chapter 3.1.1 --- Gross examination --- p.57 / Chapter 3.1.2 --- Cell viability --- p.57 / Chapter 3.1.3 --- Cartilage properties --- p.61 / Chapter 3.1.4 --- Angiogenic properties --- p.63 / Chapter 3.1.5 --- Osteogenic properties --- p.64 / Chapter 3.2 --- Implantation of scaffold-free cartilage and assessment / Chapter 3.2.1 --- Gross examination --- p.65 / Chapter 3.2.2 --- General morphology --- p.67 / Chapter 3.2.3 --- Histological scores --- p.71 / Chapter 3.2.4 --- Cell proliferation --- p.75 / Chapter 3.2.5 --- Cartilage regeneration --- p.78 / Chapter 3.2.6 --- Expression of angiogenic factor --- p.90 / Chapter 3.2.7 --- Bone regeneration --- p.93 / Chapter 3.2.8 --- Histomorphometric analysis on cartilage and bone regeneration --- p.96 / Chapter 3.2.9 --- Cell fate tracing --- p.100 / Chapter CHAPTER FOUR - --- DISCUSSION / Chapter 4.1 --- Summary of key findings / Chapter 4.1.1 --- Further characterization of BCP and determination of implantation time --- p.102 / Chapter 4.1.2 --- Implantation of BCP in OCD --- p.102 / Chapter 4.2 --- Spontaneous healing in osteochondral defect / Chapter 4.2.1 --- Findings from the current study --- p.104 / Chapter 4.2.2 --- Comparison with other studies --- p.104 / Chapter 4.2.3 --- Factors affecting spontaneous healing --- p.105 / Chapter 4.3 --- Fabrication and further characterization of the 3-D chondrocyte pellet / Chapter 4.3.1 --- Comparison of different methods of producing scaffold-free cartilage construct --- p.106 / Chapter 4.3.2 --- Cartilage phenotype of the BCP --- p.107 / Chapter 4.3.3 --- Angiogenic and osteogenic potential of the BCP --- p.108 / Chapter 4.3.4 --- Role of mechanical stimulation on tissue-engineered cartilage --- p.109 / Chapter 4.4 --- Repair of osteochondral defect with allogeneic scaffold-free cartilage / Chapter 4.4.1 --- Advantages of the current scaffold-free chondrocyte pellet --- p.111 / Chapter 4.4.2 --- Remodeling of BCP after implantation --- p.111 / Chapter 4.4.3 --- Effect of BCP on cartilage repair --- p.112 / Chapter 4.4.4 --- Effect of BCP on bone regeneration / Chapter 4.4.4.1 --- Findings in the present study --- p.113 / Chapter 4.4.4.2 --- Possible reasons of slow bone repair --- p.114 / Chapter 4.4.4.3 --- Effect of BCP on bone region peripheral to defect --- p.115 / Chapter 4.4.5 --- Immunorejection-free properties of the BCP --- p.116 / Chapter 4.4.6 --- Comparison with other animal studies using scaffold-free cartilage --- p.117 / Chapter 4.4.7 --- Possibility of implanting a BCP cultured for shorter or longer period --- p.118 / Chapter 4.4.8 --- Scaffold-free cartilage construct and construct with scaffold for OCD repair --- p.119 / Chapter 4.4.9 --- Chondrocytes and stem cells for OCD repair --- p.120 / Chapter 4.5 --- Limitations of the study / Chapter 4.5.1 --- Animal model --- p.122 / Chapter 4.5.2 --- Histomorphometric analysis --- p.122 / Chapter 4.5.3 --- Lack of quantitative data analysis --- p.122 / Chapter 4.5.4 --- BrdU labeling of cells --- p.123 / Chapter 4.5.5 --- Lack of biomechanical test --- p.123 / Chapter 4.5.6 --- Small sample size --- p.123 / Chapter CHAPTER FIVE - --- CONCLUSION --- p.124 / Chapter CHAPTER SIX - --- FUTURE STUDIES / Chapter 6.1 --- Identification of factors affecting bone repair after OCD treatment --- p.125 / Chapter 6.2 --- Modifications of BCP treatment --- p.125 / Chapter 6.3 --- Alternative cell source --- p.126 / Chapter 6.4 --- Alternative cell tracking methods --- p.126 / Chapter 6.5 --- Inclusion of biomechanical test --- p.126 / APPENDICES / Appendix 1. Conference paper 1 --- p.129 / Appendix 2: Conference paper 2 --- p.130 / Appendix 3: Animal experimentation ethics approval --- p.131 / BIBLIOGRAPHY --- p.132

1 Abstract Introduction Autologous transplants of the cartilage tissue from the pinna is commonly used in reconstructive surgery of the nasal skeleton. The present study used animal models to elucidate responses of the auricular cartilage to its damage or transplantation to ectopic sites. Histomorphological analysis of changes observed in auricular cartilage including immunohistochemical study of different isoforms of actin and S-100 proteins was performed. Human articular cartilage prepared by in vitro cultivation using artificial scaffolds was also studied after its transplantation. Aims of the study The aim was to study histological changes and expression of chondrocytic markers (α- SMA and S-100 proteins) in intact, artificially traumatised, or in a human auricular cartilage cultivated in culture medium. An attempt to grow human auricular cartilage chondrocytes implanted in vitro into various types of three dimensional scaffolds aimed at testing chondrocyte survival and phenotype both in the culture and after transplantation to immunodeficient mice. A human auricular cartilage transplanted into the nasal skeleton of patients during a reconstruction surgery should be submitted to a histomorphological examination. Research assumed also comparison of the auricular cartilage responses to a damage,...

1 Abstract Introduction Autologous transplants of the cartilage tissue from the pinna is commonly used in reconstructive surgery of the nasal skeleton. The present study used animal models to elucidate responses of the auricular cartilage to its damage or transplantation to ectopic sites. Histomorphological analysis of changes observed in auricular cartilage including immunohistochemical study of different isoforms of actin and S-100 proteins was performed. Human articular cartilage prepared by in vitro cultivation using artificial scaffolds was also studied after its transplantation. Aims of the study The aim was to study histological changes and expression of chondrocytic markers (α- SMA and S-100 proteins) in intact, artificially traumatised, or in a human auricular cartilage cultivated in culture medium. An attempt to grow human auricular cartilage chondrocytes implanted in vitro into various types of three dimensional scaffolds aimed at testing chondrocyte survival and phenotype both in the culture and after transplantation to immunodeficient mice. A human auricular cartilage transplanted into the nasal skeleton of patients during a reconstruction surgery should be submitted to a histomorphological examination. Research assumed also comparison of the auricular cartilage responses to a damage,...