Integrated Cell Landscape and Dynamics in the Progression of Bone Repair

Bone homeostasis and repair is a systematic progress with spatiotemporal interaction of multiple cell types involved in skeletal and immune system. Precise spatiotemporal regulation of cell type-specific functions in bone repair contributes to further development of tissue engineering and regenerative medicine. Here, we utilized single-cell RNA sequencing to illustrate a map of cell landscape and dynamics in the progression of rodent bone self-healing and a perturbation by lymphoid cell-deficiency. We identified different functions of myeloid cell and lymphoid cell to osteogenesis and angiogenesis during bone repair and their mutual complementation under lymphoid cell-deficient condition. Additionally, we used CD34+ humanized reconstituted mice to reveal further insights into the mechanism of human bone homeostasis and repair. Our integrated cellular analysis of bone repair explores the functional diversity and complementation between myeloid cells and lymphoid cells during bone healing process and provides further therapeutic implications for the treatment of bone disease and degeneration following ageing.