Hidden Peach-Fuzz Itch Pathway Revealed in Mice

University of Michigan researchers identify a dedicated population of touch-sensitive neurons that innervate fine vellus-like hairs (peach fuzz) and transmit mechanical itch in a mouse model of chronic skin inflammation. Removing or silencing these neurons markedly reduces scratching, and activating them with blue light reproduces itch behavior, confirming causality. The study also maps transmission proteins linking hairs to the spinal cord, with human neurons responding to the same proteins, suggesting a conserved mechanism and a potential new therapeutic target for persistent itch in eczema and related conditions.