Your skin has a thermostat — scientists at Rockefeller just found the immune cells that run it

Washing your hands, a change in weather, the microbes living on your skin: your skin's surface is in constant negotiation with the world, and its stem cells must decide, moment by moment, whether to make new cells or mature ones. A Rockefeller University team led by Elaine Fuchs has found the circuit that co-ordinates it, publishing in Science. Immune cells called Langerhans cells sense microbes at the surface and release a signal molecule that acts like a brake on stem-cell division — a rheostat (a dimmer switch for cell growth) that keeps the barrier strong and its microbes in balance. Without the brake, stem cells rush out half-finished cells and the barrier weakens. 'Even something as mundane as washing your hands may require this type of fine-tuned regulation,' said Fuchs.

SDG 3 · Good health and well-being — Mechanism: tech innovation