Fig. 4.

(i) Mechanical stimulation bioreactor system. (a) Front view depicting the bioreactor stand (anodized in blue) and the removable polycarbonate culture chamber. (b) Close-up view of PTFE pistons lowered into a standard 24-well plate on the actuator-driven sliding platform. (c) Shear deformation of hydrogel construct fully immersed in culture media. Reprinted with permission from [69]. (ii) (A) CAD design of cartilage-on-a-chip device. (B) Photograph of an actual cartilage-on-a-chip device showing loading of cell-laden hydrogel in the top chamber. (C) Overview picture of three cell culture chambers and right side showing one individual culture chamber featuring CMFDA-stained primary equine chondrocytes cultivated on-chip. (D) Intact cell-laden fibrin hydrogel clot released from the device before downstream analyses and (E) histological section of chondrocytes-on-a-chip. Reprinted from publication [75], Copyright (2021) with permission from Elsevier