Scaffold-free approach produces neocartilage tissue of similar quality as the use of HyStem™ and Hydromatrix™ scaffolds

Abstract

Numerous biomaterials are being considered for cartilage tissue engineering, while scaffold-free systems have also been introduced. Thus, it is important to know do the scaffolds improve the formation of manufactured neocartilages. This study compares scaffold-free cultures to two scaffold-containing ones. Six million bovine primary chondrocytes were embedded in HyStem™ or HydroMatrix™ scaffolds, or suspended in scaffold-free chondrocyte culture medium, and then loaded into agarose gel supported culture well pockets. Neocartilages were grown in the presence of hypertonic high glucose DMEM medium for up to 6 weeks. By the end of culture periods, the formed tissues were analyzed by histological staining for proteoglycans (PGs) and type II collagen, gene expression measurements of aggrecan, Sox9, procollagen α1(II), and procollagen α2(I) were performed using quantitative RT-PCR, and analyses of PG contents and structure were conducted by spectrophotometric and agarose gel electrophoretic methods. Histological stainings showed that the PGs and type II collagen were abundantly present in both the scaffold-free and the scaffold-containing tissues. The PG content gradually increased following the culture period. However, the mRNA expression levels of the cartilage-specific genes of aggrecan, procollagen α1(II) and Sox9 gradually decreased following culture period, while procollagen α2(I) levels increased. After 6-week-cultivations, the PG concentrations in neocartilage tissues manufactured with HyStem™ or HydroMatrix™ scaffolds, and in scaffold-free agarose gel-supported cell cultures, were similar to native cartilage. No obvious benefits could be seen on the extracellular matrix assembly in HyStem™ or HydroMatrix™ scaffolds cultures.Graphical abstract

Challenges in Fabrication of Tissue-Engineered Cartilage with Correct Cellular Colonization and Extracellular Matrix Assembly

“…Hystem™ is a commercial trademark of thiol-modified hyaluronan hydrogel kit, which contains Glycosil ® , thiol-reactive cross-linker, Extralink ® , and possible additional additives, such as denatured collagen fibers, to improve cellular adhesion properties. It offers a functional three-dimensional platform differing in pore sizes and cross-linking, and the chondrocytes seeded in it could produce a cartilage-type of tissue, which matures along the prolonged culture time [ 96 ]. However, a clear potency to improve in vitro neocartilage tissue formation has not been seen, although the embedded chondrocytes apparently have a good capacity to grow and synthesize abundant ECM in in vitro cultivated scaffolds [ 96 ].…”

“…It offers a functional three-dimensional platform differing in pore sizes and cross-linking, and the chondrocytes seeded in it could produce a cartilage-type of tissue, which matures along the prolonged culture time [ 96 ]. However, a clear potency to improve in vitro neocartilage tissue formation has not been seen, although the embedded chondrocytes apparently have a good capacity to grow and synthesize abundant ECM in in vitro cultivated scaffolds [ 96 ]. Thus, additional studies are needed to determine whether thiol-modified hyaluronan hydrogels can be applied for cartilage repair tissue engineering in future.…”

Construction of Lung Tumor Model for Drug Screening Based on 3D Bio-Printing Technology

“…It can be customized to meet speci c needs and can be used for continuous culture of multiple cell lines. There are many related products and applications: Cultrex® 3D culture tools 17 , VitroGel™3D hydrogel system 18 , and HydroMatrix™ polypeptide hydrogel 19 . (2) Cell aggregation.…”

Development of in situ crosslinked hyaluronan as an adjunct to vitrectomy surgery

“…Since then, HA products have contributed to technological innovation in ocular surgery due to their high biocompatibility, optical transparency, and rheological properties such as adhesion, elasticity, and cohesiveness [ 17 – 20 ]. Although off-label in vitrectomy, HA products also have been applied to various vitrectomy surgeries such as chromovitrectomy [ 21 – 23 ], viscodelamination [ 25 ], and viscodissection [ 26 ]. However, almost none of these techniques became common for various reasons.…”