Bioprinting is a promising technique that has the ability to generate complex tissue structures for articular cartilage (AC) repair and regeneration. However, most biomaterials used for bioprinting are incapable of representing the complexity of native extracellular matrix (ECM). In this study, a novel cartilage specific bioink has been developed with tyramine modified hyaluronic acid (THA) and decellularized ECM (dECM) of AC for threedimensional bioprinting, combining the printable qualities of THA with AC dECM to create an optimized microenvironment. First, the influence of increasing concentrations of
AC dECM on the rheological and printability properties was assessed. Next, human mesenchymal stem cells (hMSCs) were incorporated into bioinks composed of 2.5% w/v THA and AC dECM (0.0%-1.0% w/v). The THA-AC dECM bioinks have been successfully bioprinted into stable scaffolds with viable cells and were cultured for 28 days in chondrogenic differentiation medium. Subsequently, the effect of combining AC dECM with THA was evaluated by measuring the cell viability, cell differentiation and AC tissue deposition. The ink compositions with AC dECM (0.5% and 1.0% w/v) caused an increase in ink viscosity, yield stress and damping factor compared to the THA ink, but still showed shear thinning behavior and provided good printability. Spread cell morphology was observed for the scaffolds with addition of AC dECM compared to AC dECM free control with only THA, indicating enhanced cell adhesion to the hydrogel network. Moreover, a higher production of sulfated glycosaminoglycans (sGAGs) was observed for the scaffolds where AC dECM was added. The THA and AC dECM bioink composition showed promising results for AC tissue engineering and warrants further research into the development of bioinks with tissue-specific inductive properties.