Differential effect of P2X7 receptors on proliferation and migration of human keratinocytes and dermal fibroblasts

Purinergic P2X7 receptors are involved in cellular processes such as inflammation, proliferation, and tissue remodeling, although their significance in human skin physiology remains poorly understood. In this study, we demonstrated strong P2X7 receptor immunoreactivity in the basal and granular layers of the epidermis. Cutaneous expression of P2X7 receptors was further confirmed at the level of specific mRNA and protein in cultured primary human keratinocytes and dermal fibroblasts. To reveal a possible role of these receptors in regulation of keratinocyte and fibroblast function, the cells were treated with a P2X7 agonist BzATP, or its selective antagonist A438079. Cell proliferation and viability were assessed using an immunofluorescence-based cell counter, and cell migration was evaluated by wound healing assay. P2X7 stimulation with BzATP significantly inhibited keratinocyte proliferation and migration, while P2X7 inhibition with A438079 significantly enhanced keratinocyte migration. In contrast, fibroblasts displayed minimal response to either treatment. These findings indicate that P2X7 regulates keratinocyte growth, and purinergic signaling may play a role in the skin. Our data also suggest that selective P2X7 inhibition may support re-epithelialization under conditions associated with impaired wound healing.