3D Bioprinting of Hyaline Cartilage using Nasal Chondrocytes
Creators: Lan, Xiaoyi
Publisher: name: University of Alberta Library
Year: 2023

<p>Hyaline cartilage is a strong and flexible connective tissue found throughout the human body. It provides important structural and functional support for the nose, ribs, larynx, and trachea. Due to the avascular nature of the hyaline cartilage, its defects or lesions are non-regeneratable and non-healing, which can progress into diseases such as osteoarthritis (OA) or nasal airway obstruction and result in severe clinical complications. Cell-based cartilage tissue engineering using 3D bioprinting techniques can generate functionalized cartilage replacement in vitro using autologous cells, which can become a promising prospective treatment for these defects and lesions. The 3D bioprinting techniques allow on-demand fabrication of engineered and patient-specific cartilage tissue to replace damaged tissue and restore normal cartilage functions. However, existing 3D bioprinting research primarily focuses on the formulation and engineering of biomaterials, yet lacks thorough biochemical evaluations and substantial evidence to indicate the clinical potential of the bioprinted cartilage. To address this challenge, this thesis focuses on 3D bioprinting and regeneration of hyaline cartilage using naturally derived polymer, with in-depth evaluations of appropriate cell sources, in vitro, and in vivo biochemical and biomechanical performance of the engineered tissue.</p>

<p>Chapter 1 introduces the research topic with a review of hyaline cartilage structure, biochemical and biomechanical properties, potential cell source for engineered cartilage tissue, and suitable bioink materials used for 3D bioprinting. This review suggests that nasal chondrocytes are among the most suitable cell sources for hyaline cartilage regeneration. Chapter 2 provides insights into the rheological and viscoelastic properties of collagen and their roles in micro-extrusion bioprinting.</p>

<p>The first project (Chapter 3) describes the 3D bioprinting of cartilage tissue using nasal chondrocytes laden type I collagen as bioink. A biomimicry shape with non-cytotoxicity was generated using a state-of-the-art freeform reversible embedding of suspended hydrogels (FRESH) 3D bioprinting technique. The engineered cartilage showed comparable biochemical properties to native nasal cartilage. The mechanical characterization and in vivo stability of the engineered nasal cartilage substitutes were needed to further support its potential for clinical application and formation of patient-specific surgical-ready shapes. Therefore, the second project (Chapter 4) extends this study and investigates chondrogenic culture&#39;s effects on the biochemical and mechanical properties of bioprinted constructs of nasal chondrocytes in vitro and in vivo in nude mice. Engineered nasal cartilage from nasal chondrocytes seeded on clinically approved type I/III collagen membrane scaffolds (Chondro-Gide) served as a control. The results showed excellent in vitro and in vivo performances comparable to those of clinically approved scaffolds. To further improve the printability and the shape integrity of collagen bioink, the third project (Chapter 5) used pre-crosslinked methacrylate collagen with thiolate hyaluronic acid and Poly(ethylene glycol) diacrylate (PEGDA) crosslinker as a bioink to investigate the printability and in vitro chondrogenesis. This novel bioink showed significantly improved printability, shape and size retention, and biochemical indicators compared to a collagen-only bioink.</p>

<p>This thesis extensively studied 3D bioprinting and regeneration of hyaline cartilage using type I collagen-based hydrogels with nasal chondrocytes. The study results pave the way for the clinical application of 3D bioprinting to treat cartilage defects.</p>