Bioengineered articular cartilage biomimetic organ-on-a-chip using microfluidics

Cartilage tissue engineering is complex owing to the apt choice of biopolymers, cell source and dynamic simulation. Herein, we elucidate a novel approach to mesenchymal stem cells (MSCs)- induced chondrogenesis using microfluidics on an organ-on-a-chip (OOAC) model, coupled with decellularized extracellular matrix (dECM) as bioink additive, on optimised composite hydrogel. The hydrogel displayed a compression modulus of 0.18 MPa and tensile strength of 0.4 MPa. Microfluidic shear pressures of 150 mbar and 50 mbar were optimised to attain the superficial and middle zones respectively, with a media flow rate of 5 µL min−1. Gene/protein expression revealed upregulation of collagen type II, aggrecan, and laminin suggestive of chondrogenesis. The OOAC tissue constructs showed non-linear behaviour with tensile strength of 1.01 MPa. The role of microfluidics, bioink and composite hydrogel on MSCs demonstrated notable advancements towards developing hyaline cartilage biomimetics resembling structural and biomechanical properties of native cartilage, thereby serving as a disease model.