Stem cell secretome armed magneto-actuated micromotors as spatio-temporal manipulators for wound healing acceleration

Healing complex wounds, especially deep injuries, requires therapies that can target different healing phases while penetrating physical barriers like fibrin clots and scab. Existing approaches fail to fully address these spatiotemporal challenges due to reliance on passive drug diffusion. Here, we develop magnetic microspheres loaded with therapeutic factors derived from stem cells (collectively called the "secretome") to actively guide wound repair. These microspheres provide sustained release of bioactive factors and can be precisely navigated using external magnetic fields. In vitro, they exhibit potent anti-inflammatory effects and progressively enhance skin cell proliferation and migration. Unlike conventional therapies, magnetic propulsion allows them to penetrate dense wound barriers more effectively. In male murine full-thickness wounds, the micromotors accelerate healing by promoting tissue regeneration, reducing inflammation, and improving collagen and blood vessel formation. Successful results in male pigs further confirm their cross-species potential. By combining magnetic mobility with a composite bioactive secretome, this platform overcomes both spatial and temporal limitations in wound treatment.