The development of natural polymer scaffold-based therapeutics for osteochondral repair

Abstract

Due to the limited regenerative capacity of cartilage, untreated joint defects can advance to more extensive degenerative conditions such as osteoarthritis. While some biomaterial-based tissue-engineered scaffolds have shown promise in treating such defects, no scaffold has been widely accepted by clinicians to date. Multi-layered natural polymer scaffolds that mimic native osteochondral tissue and facilitate the regeneration of both articular cartilage (AC) and subchondral bone (SCB) in spatially distinct regions have recently entered clinical use, while the transient localized delivery of growth factors and even therapeutic genes has also been proposed to better regulate and promote new tissue formation. Furthermore, new manufacturing methods such as 3D bioprinting have made it possible to precisely tailor scaffold micro-architectures and/or to control the spatial deposition of cells in requisite layers of an implant. In this way, natural and synthetic polymers can be combined to yield bioactive, yet mechanically robust, cell-laden scaffolds suitable for the osteochondral environment. This mini-review discusses recent advances in scaffolds for osteochondral repair, with particular focus on the role of natural polymers in providing regenerative templates for treatment of both AC and SCB in articular joint defects.

Systematic Comparison of Biomaterials‐Based Strategies for Osteochondral and Chondral Repair in Large Animal Models

“…[ 15 ] and Chen et al. [ 16 ] Additional publications are also recommended for a more thorough review of regenerative biomaterials for OCD repair [ 17 ] and biofabrication‐based techniques for cartilage repair. [ 18 ]…”

Nature-Inspired Unconventional Approaches to Develop 3D Bioceramic Scaffolds with Enhanced Regenerative Ability

“…The sintering process is effective as it induces coalescence of the primary particles while reducing the intergranular void volume. However, if we focus on nanocrystalline, ion-doped apatites, reputed as golden biomaterials for bone regeneration, the sintering process yields its stabilisation into stoichiometric, microcrystalline hydroxyapatite, thus losing all its osteogenic and biosolubility properties, which are strictly related to the disordered, unstable nature of biological-like apatitic phases [ 162 ]. From a geometrical perspective, the pore coalescence related to the sintering process provokes the loss of the nanosize porosity, raises the specific surface area, and reduces the wettability.…”

Articulation inspired by nature: a review of biomimetic and biologically active 3D printed scaffolds for cartilage tissue engineering

“…TE, also known as regenerative medicine, is an emerging multi-disciplinary field of modern medicine which uses a combination of biomaterials, cells and bioactive factors or gene therapeutics, sometimes referred to as the ‘TE triad’, to bioengineer living tissues for a range of applications. 3 These diverse applications range from disease modelling 4 and organ-on-a-chip development, 5 to the regeneration of a variety of tissue types including cardiac tissue, 6 musculoskeletal tissue 7 and skin, 8 amongst others. In essence, the field of TE relies on the fabrication of biomaterial implants called ‘scaffolds’, which can support cell growth and whose microenvironment, architecture and functionality mimic that of native human tissue.…”