Impacts of immune microenvironment on musculoskeletal health

Understanding the interplay between immune cells and the bone marrow microenvironment is crucial for elucidating age-related musculoskeletal changes. In this commentary manuscript, we summarized that studies have shown that proinflammatory immune cells in the bone marrow, such as macrophages and neutrophils, can inhibit bone formation by secreting grancalcin. Research on skeletal stem cells (SSCs) in aged mice reveals a shift towards pro-inflammatory gene expression, affecting their osteogenic potential, while another study maps age-related changes in cranial SSC niches, emphasizing the role of the CXCL12–CXCR4 axis in stem cell-immune cell communication, Additionally, the immune system influences hematopoietic stem cells (HSCs); Niche ageing and accumulation of mutations with age lead to HSC exhaustion and a bias towards myeloid differentiation, with toll-like receptors playing a key role in maintaining hematopoiesis and bone metabolism balance.