<p>A novel, self-assembled artificial cartilage&ndash;hydroxyapatite conjugate for combined articular cartilage and subchondral bone repair: histopathological analysis of cartilage tissue engineering in rat knee joints</p>

Abstract

Purpose We previously created a self-assembled cartilage-like complex in vitro from only three cartilage components, hyaluronic acid (HA), aggrecan (AG) and type II collagen, without other materials such as cross-linking agents. Based on this self-organized AG/HA/collagen complex, we have created three novel types of biphasic cartilage and bone-like scaffolds combined with hydroxyapatite (HAP) for osteochondral tissue engineering. These scaffolds have been developed from self-assembled cartilage component molecules and HAP at the nanometer scale by manipulating the intermolecular relations. Patients and methods The surface structure of each self-organized biphasic cartilage and bone-like scaffold was evaluated by scanning electron microscopy, whereas the viscoelasticity was also analyzed in vitro. Three types of artificial cartilage–HAP conjugates were implanted into an osteochondral defect in rat knee joints, and bone and cartilage tissues of the implanted site were examined 4 and 8 weeks after implantation. The tissues were examined histopathologically to evaluate the effects of the implantation on the articular cartilage and subchondral bone tissues. Results Our in vitro and in vivo data reveal that the self-organized biphasic cartilage and bone-like scaffold conjugated with HAP are superior to the scaffold with no HAP in both cartilage regeneration and subchondral bone regeneration. Conclusion Our present study indicates that the self-organized biphasic cartilage and bone-like scaffold, which is conjugated with an HAP layer, may have potential not only to repair articular cartilage defects but also to ameliorate the degeneration of subchondral bone in the diseases with osteochondral defect.

Effect of Pore Size on Cell Behavior Using Melt Electrowritten Scaffolds

“…In recent years, tissue engineering technology has made tremendous contributions to tissue regeneration (Guo et al, 2018;Cunniffe et al, 2019;Ruvinov et al, 2019). Tissue engineering technology simulates the regeneration of tissues and organs by combining elements such as biological materials, cells, and biologically active molecules to mimic the structure and function of native tissues and organs (Kang et al, 2018;Kumai et al, 2019). These studies reveal that tissue engineering scaffolds are vital components, whose composition and structure affect the proliferation, differentiation, and gene expression in cells (Mannoor et al, 2013;Li et al, 2017;Schon et al, 2017;Wang et al, 2018).…”

Implantation of Various Cell-Free Matrixes Does Not Contribute to the Restoration of Hyaline Cartilage within Full-Thickness Focal Defects

“…Thus, cell-free approaches may be unsuccessful in cartilage tissue regeneration. Indeed, in recent research, Kumai T. et al [ 23 ] used scaffolds that are compositionally close to native tissue. They are based on aggrecan, type II collagen, and hyaluronic acid.…”

Functionalized Porous Hydroxyapatite Scaffolds for Tissue Engineering Applications: A Focused Review

“…The HAP coated self-organized cartilage-like biomaterial has the cartilage-specific tissue properties such as high elasticity and high lubrication compared to the self-organized cartilage-like complex without HAP layer coating. Interestingly, the developed biomaterial ability is tested by implanting in rat knee joints and histopathological analysis signifies their importance in the utilization of designed biomaterials for cartilage tissue engineering …”