Chondrogenesis Of Chondrocytes Research Articles

Genetically engineered chondrocytes overexpressing elastin improve cell retention and chondrogenesis in a three-dimensional GelMA culture system.

Elastic cartilage possesses many elastic fibers and has a high degree of elasticity. However, insufficient elastic fiber production remains unsolved in elastic cartilage tissue engineering. Exogenous elastin is difficult to degrade and violates cell proliferation and migration during cartilage regeneration. Moreover, exogenous elastic fibers are difficult to assemble with endogenous extracellular matrixcomponents. We produced genetically engineered chondrocytes overexpressing elastin to boost endogenous elastic fiber production. After identifying that genetic manipulation hardly impacted the cell viability and chondrogenesis of chondrocytes, we co-cultured genetically engineered chondrocytes with untreated chondrocytes in a three-dimensionalgelatin methacryloyl (GelMA) system. In vitro study showed that the co-culture system produced more elastic fibers and increased cell retention, resulting in strengthened mechanics than the control system with untreated chondrocytes. Moreover, in vivo implantation revealed that the co-culture GelMA system greatly resisted host tissue invasion by promoting elastic fiber production and cartilage tissue regeneration compared with the control system. In summary, our study indicated that genetically engineered chondrocytes overexpressing elastin are efficient and safe for promoting elastic fiber production and cartilage regeneration in elastic cartilage tissue engineering.

Bio-ink development for three-dimensional bioprinting of hetero-cellular cartilage constructs

ABSTRACTBioprinting is a promising tool to fabricate organized cartilage. This study aimed to investigate the printability of gelatin-methacryloyl/gellan gum (gelMA/gellan) hydrogels with and without methacrylated hyaluronic acid (HAMA), and to explore (zone-specific) chondrogenesis of chondrocytes, articular cartilage progenitor cells (ACPCs), and multipotent mesenchymal stromal cells (MSCs) embedded in these bio-inks.The incorporating of HAMA in gelMA/gellan bio-ink increased filament stability, as measured using a filament collapse assay, but did not influence (zone-specific) chondrogenesis of any of the cell types. Highest chondrogenic potential was observed for MSCs, followed by ACPCs, which displayed relatively high proteoglycan IV mRNA levels. Therefore, two-zone constructs were printed with gelMA/gellan/HAMA containing ACPCs in the superficial region and MSCs in the middle/deep region. Chondrogenic differentiation was confirmed, however, printing influence cellular differentiation.ACPC- and MSC-laden gelMA/gellan/HAMA hydrogels are of interest for the fabrication of cartilage constructs. Nevertheless, this study underscores the need for careful evaluation of the effects of printing on cellular differentiation.