Single‐cell RNA sequencing in osteoarthritis

Osteoarthritis is a progressive and heterogeneous joint disease with complex pathogenesis. The various phenotypes associated with each patient suggest that better subgrouping of tissues associated with genotypes in different phases of osteoarthritis may provide new insights into the onset and progression of the disease. Recently, single‐cell RNA sequencing was used to describe osteoarthritis pathogenesis on a high‐resolution view surpassing traditional technologies. Herein, this review summarizes the microstructural changes in articular cartilage, meniscus, synovium and subchondral bone that are mainly due to crosstalk amongst chondrocytes, osteoblasts, fibroblasts and endothelial cells during osteoarthritis progression. Next, we focus on the promising targets discovered by single‐cell RNA sequencing and its potential applications in target drugs and tissue engineering. Additionally, the limited amount of research on the evaluation of bone‐related biomaterials is reviewed. Based on the pre‐clinical findings, we elaborate on the potential clinical values of single‐cell RNA sequencing for the therapeutic strategies of osteoarthritis. Finally, a perspective on the future development of patient‐centred medicine for osteoarthritis therapy combining other single‐cell multi‐omics technologies is discussed. This review will provide new insights into osteoarthritis pathogenesis on a cellular level and the field of applications of single‐cell RNA sequencing in personalized therapeutics for osteoarthritis in the future.