Transient Skin Stretching Stimulates Immune Surveillance and Promotes Vaccine Delivery via Hair Follicles

The study investigates the effects of transient skin stretching, such as skin rubbing, on immune surveillance and vaccine delivery. It demonstrates that a single instance of skin stretching can re-orient collagen fibers, activate mechano-transduction in stromal cells, and recruit immune cells to the skin. This process increases skin permeability by opening hair follicles without causing tissue damage. The changes also activate dermal dendritic cells through exposure to skin microbiota-derived compounds. The research highlights the potential of using skin stretching for needle-free vaccine delivery, which enhances antigen accumulation in lymph nodes and elicits a stronger immune response compared to traditional intramuscular injections. These findings have significant implications for drug delivery and the understanding of mechanobiology.