3D Bioprinting for Cartilage and Osteochondral Tissue Engineering

Abstract

Significant progress has been made in the field of cartilage and bone tissue engineering over the last two decades. As a result, there is real promise that strategies to regenerate rather than replace damaged or diseased bones and joints will one day reach the clinic however, a number of major challenges must still be addressed before this becomes a reality. These include vascularization in the context of large bone defect repair, engineering complex gradients for bone‐soft tissue interface regeneration and recapitulating the stratified zonal architecture present in many adult tissues such as articular cartilage. Tissue engineered constructs typically lack such spatial complexity in cell types and tissue organization, which may explain their relatively limited success to date. This has led to increased interest in bioprinting technologies in the field of musculoskeletal tissue engineering. The additive, layer by layer nature of such biofabrication strategies makes it possible to generate zonal distributions of cells, matrix and bioactive cues in 3D. The adoption of biofabrication technology in musculoskeletal tissue engineering may therefore make it possible to produce the next generation of biological implants capable of treating a range of conditions. Here, advances in bioprinting for cartilage and osteochondral tissue engineering are reviewed.

Nanocomposite bioink exploits dynamic covalent bonds between nanoparticles and polysaccharides for precision bioprinting

“…Cartilage is one of the most studied tissue in bioprinting because it contains only single cell type and is not vascularized so that the tissue is considered to be relatively easy to fabricate compared to other tissue. [40] In addition, there are high clinical demands for generation of patient-tailored articular or auricular cartilage to treat a number of cartilage-related diseases such as microtia/anotia, osteoarthritis or traumatic cartilage injuries. [41,42] However, in vitro promotion of matrix deposition by chondrocytes isolated from native tissue is often challenging in many hydrogel or composite systems.…”

Human articular cartilage repair: Sources and detection of cytotoxicity and genotoxicity in photo-crosslinkable hydrogel bioscaffolds

“…However, the crosslinking reaction can impact on cell viability and metabolism, and consequently on chondrogenic differentiation. One of the most widely adopted crosslinking strategy uses polymers (naturally derived or synthetic) which have been modified with reactive groups (methacrylate and/or methacrylamide) which can undergo chain polymerization reactions . The process of protein crosslinking comprises among all chemical, enzymatic, chemo‐enzymatic, self‐assembly, ionic, thermal formation of new covalent bonds between polypeptides .…”

“…One of the most widely adopted crosslinking strategy uses polymers (naturally derived or synthetic) which have been modified with reactive groups (methacrylate and/or methacrylamide) which can undergo chain polymerization reactions. [15][16][17] The process of protein crosslinking comprises among all chemical, enzymatic, chemo-enzymatic, self-assembly, ionic, thermal formation of new covalent bonds between polypeptides. 18 These reactions allow the site-directed coupling of proteins with distinct properties and the de novo assembly of polymeric protein networks.…”

Melt electrowritten scaffolds with bone-inspired fibrous and mineral architectures to enhance BMP2 delivery and human MSC osteogenesis

“…Through the advent of new technology such as 3D printing, precise control of scaffold architecture is now achievable [12]. Fused deposition modelling (FDM) can produce scaffolds with defined fibre architecture creating pores of differing shapes [13] in addition to facilitating mineral incorporation [14–18], which in turn drives mesenchymal stem/stromal cell (MSC) differentiation down specific lineages. However, FDM is limited in that fibre diameters below 100 μm are difficult to fabricate.…”