Abstract

Articular cartilage degeneration and traumatic cartilage defects are common disorders causing pain and disability. Many strategies were developed throughout years to address these problems. Tissue engineering approaches offer several promising solutions. Articular hyaline cartilage has very complex structure and follows a multi-layer architecture. In this study, we developed a 4-layers scaffold mimicking the fibers orientation observed within the cartilage extra-cellular matrix (ECM). Bone and cartilage microparticles were incorporated in the first and second layers, respectively, to direct the differentiation of stem cells toward subchondral bone and cartilage phenotype. The 2 upper layers were designed with random (layer 3) and aligned (layer 4) electrospun nanofibers in an attempt to mimic hyaline articular cartilage ECM orientation. Histological analysis of the scaffold showed a continuous and homogeneous structure. Moreover, we confirmed the presence of cartilage and bone microparticles in the gelatin foam-based layers (layer 1 and 2). Scanning electron microscope (SEM) confirmed the tubular, vertical, morphology of the first and second layers, thereby mimicking as intended the native hyaline cartilage structure. Water uptake and degradation rate of our scaffold appeared suitable for our application, with many options for tunability. Finally, we demonstrated that the scaffolds were biocompatible, as it promoted the survival and attachment of MIAMI cells in vitro. In this study, we described the first phases of the development of a multi-layered scaffold designed to mimic the native architecture of articular hyaline cartilage. With further refinements and testing, we hope that this strategy will pave the way for potential new advances in the field of osteochondral repair.

Keywords: Electrospinning, gelatin, human tissues, hyaline cartilage, MIAMI cells, multi-layered scaffold, nanofibers, tissue engineering.