Figure 8.

Summary of the mechanism underlying dry skin-induced pruritus. The production of TSLP in keratinocytes increases under dry skin conditions, in a TRPV4-dependent manner. Additionally, TSLP acts on TSLPR in mast cells to promote the release of tryptase, which in turn stimulates the keratinocytes via PAR2 and TRPV4 to produce more TSLP, thus generating a positive feedback loop of increased TSLP production. TSLP can also act on TSLPR in sensory neurons to transmit electrical signals towards the spinal cord, which are conveyed to the brain and finally perceived as itch.