Cartilage-on-chip for osteoarthritis drug screening

Osteoarthritis (OA) is a common disease characterized by degenerative changes in joint cartilage, manifesting clinically as joint pain, stiffness, and functional impairment. At present, the variety of drugs available for OA is relatively limited, and these primarily serve to alleviate symptoms rather than effectuate actual cartilage repair. The complex cellular environment and biochemical reactions within cartilage tissue further complicate the screening of effective drugs. Organ-on-a-chip is increasingly being applied in the field of drug screening with its ability to mimic the microenvironment and physiological functions of human organs. Herein, we developed a cartilage-on-chip by culturing primary chondrocytes in three dimensions within a microfluidic system. This novel design could maintain the cartilage phenotype and replicate its microenvironment. This cartilage-on-chip cultured under interleukin-1 beta for 3 days displayed a distinct OA-like phenotype, serving as an OA model. Furthermore, we tested different types of drugs, and the outcomes indicated that each tested drug was effective in alleviating OA using the OA-like cartilage-on-chip. Notably, the results obtained were consistent with in vivo findings, thereby validating the utility of the cartilage-on-chip as a reliable platform for drug screening. This study underscores the potential of organ-on-a-chip in advancing OA research and drug development, offering a more physiologically relevant and ethically sustainable alternative to traditional models to reduce costs and enhance efficiency.