The study, published in Nature in October 2025, shows that restoring these macrophages can rejuvenate microvascular function in ageing skin.  

Using advanced live imaging in mice, scientists observed that capillary-associated macrophages become progressively depleted with age, even more rapidly than the capillaries themselves. In both mice and human skin samples, areas lacking these cells showed poorer blood flow and slower recovery from minor vascular damage.  

When the researchers experimentally boosted macrophage numbers in older mice using a growth factor called CSF1-Fc, blood flow improved and damaged vessels repaired more efficiently. The findings suggest that maintaining or replenishing these macrophages could help counteract aspects of skin vascular ageing and improve tissue healing.  

While the research was conducted primarily in animal models, it highlights immune-cell loss as a potential therapeutic target for restoring skin function and resilience in later life.