因為關節軟骨是無血管組織並且無法獲得祖細胞，在軟骨修復上具有受限的再生潛力，當骨頭末端的保護性軟骨受損時，最終可能會導致骨關節炎(OA)，這是關節最常見的慢性疾病之一，治療方法包括使用支架和生物活性材料。在本研究中，去細胞軟骨粉(DCP)用於提供組織再生模板和富含血小板的纖維蛋白(PRF)，提供細胞因子和生長因子以加速軟骨的癒合。本研究進行體外試驗如細胞增殖和細胞毒性試驗以確認材料是否促進細胞增殖並顯示是否存在任何細胞毒性作用；體內試驗部分，在新西蘭白兔的髕股溝中製作3mm×3mm(直徑×深度)的關節軟骨缺陷，使用PRF和DCP單獨或混合填充缺陷，並以纖維蛋白膠作為粘合劑將PRF和DCP保持在缺陷內，術後4週，犧牲動物並進行肉眼觀察、CT掃描以及組織學和免疫組織化學分析。宏觀分析結果顯示，用PRF+DCP處理的軟骨表現出最佳的宏觀外觀；組織學分析顯示所有實驗組的缺損中均有新形成的膠原，證明軟骨的修復；免疫組織化學分析顯示所有實驗組均表現出透明和纖維軟骨表型的混合物。總體而言，本研究中獲得的發現可證明自體PRF和DCP可以在一定程度上成為全層軟骨修復的另一種治療選擇。

The articular cartilage has poor intrinsic healing potential since it has no blood vessels that can supply nutrients, low cellular metabolic activity and limited access to stem cells. These characteristics impose a great challenge for articular cartilage regeneration and may result to further chronic problem such as osteoarthritis. Treatment methods include the use of scaffolds and bioactive materials. In this study, decellularized cartilage powder (DCP) was used to provide the template for tissue regeneration and platelet-rich fibrin (PRF) provided the cytokines and growth factors to accelerate the healing of the cartilage. In vitro tests such as cytotoxicity and viability assay, and cell migration were performed to check if the DCP can promote cell proliferation and migration as well as detection of cytotoxic effects to infrapatellar fat pad stem cells (IFPSC). A 3 mm x 3 mm (diameter x depth) articular cartilage defects were made in the patellofemoral grooves of New Zealand white rabbits. PRF and DCP were used to fill the defects, alone or in combination. In addition, fibrin glue was used as an adhesive to keep the PRF and DCP inside the defect. Four weeks post-operation, the animals were sacrificed and subjected to macroscopic evaluation, CT scan, histological and immunohistochemical analyses. The results of macroscopic analysis showed that the cartilage treated with PRF+DCP exhibited the best macroscopic appearance. Histological analysis demonstrated signs of newly formed collagen in the defect for all treatment groups, indicating cartilage repair. However, immunohistochemical analyses showed that all the treatment groups exhibited a mixture of hyaline and fibrocartilaginous phenotype. Overall, the findings that were obtained in this study provided evidence that the autologous PRF and DCP can be another treatment option for full thickness cartilage repair to some extent.

BIBLIOGRAPHY
1. Di Bella, C., et al., 3D Bioprinting of Cartilage for Orthopedic Surgeons: Reading between the Lines. Frontiers in surgery, 2015. 2: p. 39-39.
2. Bhosale, A.M. and J.B. Richardson, Articular cartilage: structure, injuries and review of management. Br Med Bull, 2008. 87: p. 77-95.
3. Mow, V.C., A. Ratcliffe, and A.R. Poole, Cartilage and diarthrodial joints as paradigms for hierarchical materials and structures. Biomaterials, 1992. 13(2): p. 67-97.
4. Moutos, F.T. and F. Guilak, Composite scaffolds for cartilage tissue engineering. Biorheology, 2008. 45(3-4): p. 501-12.
5. Newman, A.P., Articular Cartilage Repair. The American Journal of Sports Medicine, 1998. 26(2): p. 309-324.
6. Sophia Fox, A.J., A. Bedi, and S.A. Rodeo, The basic science of articular cartilage: structure, composition, and function. Sports health, 2009. 1(6): p. 461-468.
7. Beddoes, C., et al., Hydrogels as a Replacement Material for Damaged Articular Hyaline Cartilage. Materials, 2016. 9(6): p. 443.
8. Linn, F.C. and L. Sokoloff, Movement and Composition of Interstitial Fluid of Cartilage. Arthritis Rheum, 1965. 8: p. 481-94.
9. Williamson, A.K., et al., Tensile mechanical properties of bovine articular cartilage: variations with growth and relationships to collagen network components. J Orthop Res, 2003. 21(5): p. 872-80.
10. Eyre, D.R., M.A. Weis, and J.J. Wu, Articular cartilage collagen: an irreplaceable framework? Eur Cell Mater, 2006. 12: p. 57-63.
11. Kelly, D.J., et al., Biochemical markers of the mechanical quality of engineered hyaline cartilage. J Mater Sci Mater Med, 2007. 18(2): p. 273-81.
12. Adarmes, H., et al., Glycosaminoglycans (GAGs) determination in healthy and damaged equine articular cartilage. Austral journal of veterinary sciences, 2017. 49: p. 129-133.
13. Buckwalter, J.A. and H.J. Mankin, Articular cartilage: tissue design and chondrocyte-matrix interactions. Instr Course Lect, 1998. 47: p. 477-86.
14. Yanagishita, M., Function of proteoglycans in the extracellular matrix. Acta Pathol Jpn, 1993. 43(6): p. 283-93.
15. Chen, F.S., S.R. Frenkel, and P.E. Di Cesare, Repair of articular cartilage defects: part I. Basic Science of cartilage healing. Am J Orthop (Belle Mead NJ), 1999. 28(1): p. 31-3.
16. J Responte, D., R. Natoli, and K. Athanasiou, Collagens of Articular Cartilage: Structure, Function, and Importance in Tissue Engineering. Vol. 35. 2007. 363-411.
17. Schwartz, M.H., P.H. Leo, and J.L. Lewis, A microstructural model for the elastic response of articular cartilage. Journal of Biomechanics, 1994. 27(7): p. 865-873.
18. Kovach, I.S., A molecular theory of cartilage viscoelasticity. Biophys Chem, 1996. 59(1-2): p. 61-73.
19. Maldonado, M. and J. Nam, The role of changes in extracellular matrix of cartilage in the presence of inflammation on the pathology of osteoarthritis. BioMed research international, 2013. 2013: p. 284873-284873.
20. Broom, N.D. and C.A. Poole, A functional-morphological study of the tidemark region of articular cartilage maintained in a non-viable physiological condition. Journal of anatomy, 1982. 135(Pt 1): p. 65-82.
21. Nasiri, B. and S. Mashayekhan, Fabrication of porous scaffolds with decellularized cartilage matrix for tissue engineering application. Biologicals, 2017. 48: p. 39-46.
22. Mankin, H.J., The response of articular cartilage to mechanical injury. J Bone Joint Surg Am, 1982. 64(3): p. 460-6.
23. Heinegård, D., et al., 5 - Articular cartilage, in Rheumatology (Sixth Edition), M.C. Hochberg, et al., Editors. 2015, Content Repository Only!: Philadelphia. p. 33-41.
24. Mankin, H.J. and A.Z. Thrasher, Water content and binding in normal and osteoarthritic human cartilage. J Bone Joint Surg Am, 1975. 57(1): p. 76-80.
25. Guilak, F., et al., Mechanical and biochemical changes in the superficial zone of articular cartilage in canine experimental osteoarthritis. J Orthop Res, 1994. 12(4): p. 474-84.
26. Chu, C.R., M. Szczodry, and S. Bruno, Animal models for cartilage regeneration and repair. Tissue engineering. Part B, Reviews, 2010. 16(1): p. 105-115.
27. Matsiko, A., T.J. Levingstone, and F.J. O'Brien, Advanced Strategies for Articular Cartilage Defect Repair. Materials (Basel, Switzerland), 2013. 6(2): p. 637-668.
28. Hunziker, E.B., Articular cartilage repair: are the intrinsic biological constraints undermining this process insuperable? Osteoarthritis Cartilage, 1999. 7(1): p. 15-28.
29. Shapiro, F., S. Koide, and M.J. Glimcher, Cell origin and differentiation in the repair of full-thickness defects of articular cartilage. J Bone Joint Surg Am, 1993. 75(4): p. 532-53.
30. Temenoff, J.S. and A.G. Mikos, Review: tissue engineering for regeneration of articular cartilage. Biomaterials, 2000. 21(5): p. 431-40.
31. Beris, A.E., et al., Advances in articular cartilage repair. Injury, 2005. 36 Suppl 4: p. S14-23.
32. Mizuta, H., et al., Expression of the PTH/PTHrP receptor in chondrogenic cells during the repair of full-thickness defects of articular cartilage. Osteoarthritis and Cartilage, 2006. 14(9): p. 944-952.
33. Bekkers, J.E.J., M. Inklaar, and D.B.F. Saris, Treatment Selection in Articular Cartilage Lesions of the Knee: A Systematic Review. The American Journal of Sports Medicine, 2009. 37(1_suppl): p. 148-155.
34. Poddar, S.K. and L. Widstrom, Nonoperative Options for Management of Articular Cartilage Disease. Clin Sports Med, 2017. 36(3): p. 447-456.
35. Jeuken, R., et al., Polymers in Cartilage Defect Repair of the Knee: Current Status and Future Prospects. Polymers, 2016. 8(6): p. 219.
36. Huber, M., S. Trattnig, and F. Lintner, Anatomy, biochemistry, and physiology of articular cartilage. Invest Radiol, 2000. 35(10): p. 573-80.
37. Steadman, J.R., W.G. Rodkey, and K.K. Briggs, Microfracture: Its History and Experience of the Developing Surgeon. Cartilage, 2010. 1(2): p. 78-86.
38. Knutsen, G., et al., Autologous chondrocyte implantation compared with microfracture in the knee. A randomized trial. J Bone Joint Surg Am, 2004. 86-a(3): p. 455-64.
39. Hangody, L. and P. Fules, Autologous osteochondral mosaicplasty for the treatment of full-thickness defects of weight-bearing joints: ten years of experimental and clinical experience. J Bone Joint Surg Am, 2003. 85-A Suppl 2: p. 25-32.
40. Saris, D.B., et al., Treatment of symptomatic cartilage defects of the knee: characterized chondrocyte implantation results in better clinical outcome at 36 months in a randomized trial compared to microfracture. Am J Sports Med, 2009. 37 Suppl 1: p. 10S-19S.
41. Marlovits, S., et al., Cartilage repair: generations of autologous chondrocyte transplantation. Eur J Radiol, 2006. 57(1): p. 24-31.
42. Bartlett, W., et al., Autologous chondrocyte implantation versus matrix-induced autologous chondrocyte implantation for osteochondral defects of the knee: a prospective, randomised study. J Bone Joint Surg Br, 2005. 87(5): p. 640-5.
43. Kon, E., et al., Second-generation autologous chondrocyte implantation: results in patients older than 40 years. Am J Sports Med, 2011. 39(8): p. 1668-75.
44. Behrens, P., et al., Matrix-associated autologous chondrocyte transplantation/implantation (MACT/MACI)—5-year follow-up. The Knee, 2006. 13(3): p. 194-202.
45. Horas, U., et al., Autologous chondrocyte implantation and osteochondral cylinder transplantation in cartilage repair of the knee joint. A prospective, comparative trial. J Bone Joint Surg Am, 2003. 85-A(2): p. 185-92.
46. Rahman, R.A., et al., Tissue engineering of articular cartilage: From bench to bed-side. Tissue Engineering and Regenerative Medicine, 2015. 12(1): p. 1-11.
47. Danišovič, L.u., et al., The tissue engineering of articular cartilage: cells, scaffolds and stimulating factors. Experimental Biology and Medicine, 2012. 237(1): p. 10-17.
48. Vinatier, C. and J. Guicheux, Cartilage tissue engineering: From biomaterials and stem cells to osteoarthritis treatments. Annals of Physical and Rehabilitation Medicine, 2016. 59(3): p. 139-144.
49. Darling, E.M. and K.A. Athanasiou, Rapid phenotypic changes in passaged articular chondrocyte subpopulations. Journal of Orthopaedic Research, 2005. 23(2): p. 425-432.
50. Koga, H., et al., Mesenchymal stem cell-based therapy for cartilage repair: a review. Knee Surg Sports Traumatol Arthrosc, 2009. 17(11): p. 1289-97.
51. Koga, H., et al., Comparison of mesenchymal tissues-derived stem cells for in vivo chondrogenesis: suitable conditions for cell therapy of cartilage defects in rabbit. Cell Tissue Res, 2008. 333(2): p. 207-15.
52. Tangchitphisut, P., et al., Infrapatellar Fat Pad: An Alternative Source of Adipose-Derived Mesenchymal Stem Cells. Arthritis, 2016. 2016: p. 4019873.
53. Garcia, J., et al., Characterisation of synovial fluid and infrapatellar fat pad derived mesenchymal stromal cells: The influence of tissue source and inflammatory stimulus. Scientific Reports, 2016. 6: p. 24295.
54. Toghraie, F.S., et al., Treatment of osteoarthritis with infrapatellar fat pad derived mesenchymal stem cells in Rabbit. Knee, 2011. 18(2): p. 71-5.
55. Capito, R.M. and M. Spector, Scaffold-based articular cartilage repair. IEEE Eng Med Biol Mag, 2003. 22(5): p. 42-50.
56. A., G., et al., Articular cartilage tissue engineering. The Journal of Bone and Joint Surgery. British volume, 2009. 91-B(5): p. 565-576.
57. Liu, Y., G. Zhou, and Y. Cao, Recent Progress in Cartilage Tissue Engineering—Our Experience and Future Directions. Engineering, 2017. 3(1): p. 28-35.
58. Kwon, H., et al., Articular cartilage tissue engineering: the role of signaling molecules. Cellular and Molecular Life Sciences, 2016. 73(6): p. 1173-1194.
59. van Osch, G.J., et al., Growth factors in cartilage tissue engineering. Biorheology, 2002. 39(1-2): p. 215-20.
60. Fan, H., et al., Porous gelatin-chondroitin-hyaluronate tri-copolymer scaffold containing microspheres loaded with TGF-beta1 induces differentiation of mesenchymal stem cells in vivo for enhancing cartilage repair. J Biomed Mater Res A, 2006. 77(4): p. 785-94.
61. Luyten, F.P., et al., Recombinant bone morphogenetic protein-4, transforming growth factor-beta 1, and activin A enhance the cartilage phenotype of articular chondrocytes in vitro. Exp Cell Res, 1994. 210(2): p. 224-9.
62. Fortier, L.A., et al., Insulin-like growth factor-I enhances cell-based repair of articular cartilage. J Bone Joint Surg Br, 2002. 84(2): p. 276-88.
63. Morales, T.I., The quantitative and functional relation between insulin-like growth factor-I (IGF) and IGF-binding proteins during human osteoarthritis. J Orthop Res, 2008. 26(4): p. 465-74.
64. Arora, A., et al., Cartilage Tissue Engineering: Scaffold, Cell, and Growth Factor-Based Strategies, in Regenerative Medicine: Laboratory to Clinic, A. Mukhopadhyay, Editor. 2017, Springer Singapore: Singapore. p. 233-257.
65. Solchaga, L.A., et al., Fibroblast Growth Factor-2 Enhances Proliferation and Delays Loss of Chondrogenic Potential in Human Adult Bone-Marrow-Derived Mesenchymal Stem Cells. Tissue Engineering Part A, 2010. 16(3): p. 1009-1019.
66. Yamamoto, T., et al., Fibroblast growth factor-2 promotes the repair of partial thickness defects of articular cartilage in immature rabbits but not in mature rabbits. Osteoarthritis and Cartilage, 2004. 12(8): p. 636-641.
67. Schmidt, M.B., E.H. Chen, and S.E. Lynch, A review of the effects of insulin-like growth factor and platelet derived growth factor on in vivo cartilage healing and repair. Osteoarthritis and Cartilage, 2006. 14(5): p. 403-412.
68. Tuli, R., W.-J. Li, and R.S. Tuan, Current state of cartilage tissue engineering. Arthritis research & therapy, 2003. 5(5): p. 235-238.
69. Utomo, L., et al., Preparation and characterization of a decellularized cartilage scaffold for ear cartilage reconstruction. Vol. 10. 2015. 015010.
70. Cheng, C.W., L.D. Solorio, and E. Alsberg, Decellularized tissue and cell-derived extracellular matrices as scaffolds for orthopaedic tissue engineering. Biotechnology advances, 2014. 32(2): p. 462-484.
71. Zhang, Y., et al., Tissue-specific extracellular matrix coatings for the promotion of cell proliferation and maintenance of cell phenotype. Biomaterials, 2009. 30(23-24): p. 4021-8.
72. Luo, L., et al., Decellularization of porcine articular cartilage explants and their subsequent repopulation with human chondroprogenitor cells. Journal of the Mechanical Behavior of Biomedical Materials, 2016. 55: p. 21-31.
73. Cheng, N.-C., et al., Chondrogenic Differentiation of Adipose-Derived Adult Stem Cells by a Porous Scaffold Derived from Native Articular Cartilage Extracellular Matrix. Tissue Engineering Part A, 2009. 15(2): p. 231-241.
74. Gong, Y.Y., et al., A sandwich model for engineering cartilage with acellular cartilage sheets and chondrocytes. Biomaterials, 2011. 32(9): p. 2265-2273.
75. Kang, H., et al., In vivo cartilage repair using adipose-derived stem cell-loaded decellularized cartilage ECM scaffolds. Journal of Tissue Engineering and Regenerative Medicine, 2014. 8(6): p. 442-453.
76. Wong, C.C., et al., Single-Stage Cartilage Repair Using Platelet-Rich Fibrin Scaffolds With Autologous Cartilaginous Grafts. Am J Sports Med, 2017. 45(13): p. 3128-3142.
77. Kennedy, M.I., et al., Platelet-Rich Plasma and Cartilage Repair. Curr Rev Musculoskelet Med, 2018. 11(4): p. 573-582.
78. Dohan, D.M., et al., Platelet-rich fibrin (PRF): a second-generation platelet concentrate. Part III: leucocyte activation: a new feature for platelet concentrates? Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 2006. 101(3): p. e51-5.
79. He, L., et al., A comparative study of platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) on the effect of proliferation and differentiation of rat osteoblasts in vitro. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 2009. 108(5): p. 707-13.
80. Kobayashi, E., et al., Comparative release of growth factors from PRP, PRF, and advanced-PRF. Clin Oral Investig, 2016. 20(9): p. 2353-2360.
81. Kazemi, D., et al., Canine articular cartilage regeneration using mesenchymal stem cells seeded on platelet rich fibrin. Bone & Joint Research, 2017. 6(2): p. 98-107.
82. Dohan, D.M., et al., Platelet-rich fibrin (PRF): A second-generation platelet concentrate. Part I: Technological concepts and evolution. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 2006. 101(3): p. e37-e44.
83. Dragoo, J.L., et al., Tissue-engineered cartilage and bone using stem cells from human infrapatellar fat pads. J Bone Joint Surg Br, 2003. 85(5): p. 740-7.
84. Buckley, C.T., et al., Functional properties of cartilaginous tissues engineered from infrapatellar fat pad-derived mesenchymal stem cells. J Biomech, 2010. 43(5): p. 920-6.
85. Hindle, P., et al., The Infrapatellar Fat Pad as a Source of Perivascular Stem Cells with Increased Chondrogenic Potential for Regenerative Medicine. Stem Cells Transl Med, 2017. 6(1): p. 77-87.
86. Francis, S., et al., Adipose-Derived Mesenchymal Stem Cells in the Use of Cartilage Tissue Engineering: The Need for a Rapid Isolation Procedure. Vol. 2018. 2018.
87. Riss, T.L. and R.A. Moravec, Use of Multiple Assay Endpoints to Investigate the Effects of Incubation Time, Dose of Toxin, and Plating Density in Cell-Based Cytotoxicity Assays. ASSAY and Drug Development Technologies, 2004. 2(1): p. 51-62.
88. Horváth, S., Cytotoxicity of drugs and diverse chemical agents to cell cultures. Toxicology, 1980. 16(1): p. 59-66.
89. Novakofski, K.D., et al., High-Resolution Methods for Diagnosing Cartilage Damage In Vivo. Cartilage, 2016. 7(1): p. 39-51.
90. Bianchi, V.J., et al., Redifferentiated Chondrocytes for the Repair of Articular Cartilage Lesions. Orthopaedic Journal of Sports Medicine, 2017. 5(7 suppl6): p. 2325967117S00228.
91. Recha-Sancho, L., et al., Dedifferentiated Human Articular Chondrocytes Redifferentiate to a Cartilage-Like Tissue Phenotype in a Poly(ε-Caprolactone)/Self-Assembling Peptide Composite Scaffold. Materials (Basel, Switzerland), 2016. 9(6): p. 472.
92. Aigner, T., et al., SOX9 expression does not correlate with type II collagen expression in adult articular chondrocytes. Matrix Biol, 2003. 22(4): p. 363-72.
93. Iwasa, J., et al., Clinical application of scaffolds for cartilage tissue engineering. Knee Surg Sports Traumatol Arthrosc, 2009. 17(6): p. 561-77.
94. Gille, J., et al., Migration pattern, morphology and viability of cells suspended in or sealed with fibrin glue: A histomorphologic study. Tissue and Cell, 2005. 37(5): p. 339-348.
95. Hardingham, T.E. and A.J. Fosang, Proteoglycans: many forms and many functions. FASEB J, 1992. 6(3): p. 861-70.
96. Tekari, A., et al., Chondrocytes expressing intracellular collagen type II enter the cell cycle and co-express collagen type I in monolayer culture. Journal of Orthopaedic Research, 2014. 32(11): p. 1503-1511.