Hair follicles engage in chemosensation: Olfactory receptor OR2AT4 regulates human hair growth

Olfactory receptors (OR) regulate physiological cell functions beyond olfaction. Here, we show that human hair follicle (HF) epithelium engages in chemosensation: it expresses OR2AT4, whose stimulation by a synthetic sandalwood odorant (prolongs hair growth (anagen) ex vivo via increased IGF-1 production. Instead, OR2AT4-silencing inhibits hair growth. Thus, human HFs can “smell” and require OR2AT4-mediated signaling to sustain their growth, inviting novel therapeutic hair growth regulation by targeting HF chemosensation. 4 different donors for each experiment (Vehicle untreated vs Sandalore 500μM and Scrambled oligos vs siRNA OR2AT4)