ATP release and P2Y receptor signalling are essential for keratinocyte galvanotaxis

Repair to damaged tissue requires directional cell migration to heal the wound. Immediately upon wounding an electrical guidance cue is created with the cathode of the electric field (EF) located at the center of the wound. Previous research has demonstrated directional migration of keratinocytes towards the cathode when an EF of physiological strength (100–150 mV/mm) is applied in vitro, but the “sensor” by which keratinocytes sense the EF remains elusive. Here we use a customised chamber design to facilitate the application ofa direct current (DC) EF of physiological strength (100 mV/mm) to keratinocytes whilst pharmacologically modulating the activation ofboth connexin hemichannels and purinergic receptorsto determine their role inEF-mediated directional keratinocyte migration, galvanotaxis. In addition, keratinocytes were exposed to DiSCAC2(3) dye to visualize membrane potential changes within the cell upon exposure to the applied DC EF. Here we unveil ATP-medicated mechanisms that underpin the initiation of keratinocyte galvanotaxis. The application of a DC EF of 100 mV/mm releases ATP via hemichannels activatinga subset of purinergic P2Y receptors, locally, to initiate the directional migration of keratinocytes towards the cathodein vitro, the center of the woundin vivo. The delineation of the mechanisms underpinning galvanotaxis extends our understanding of this endogenous cue and will facilitate the optimization and wider use of EF devices for chronic wound treatment. This article is protected by copyright. All rights reserved