620 Inflammasome activation in human keratinocytes and mouse epidermis by ultraviolet radiation

Abstract

Ultraviolet B radiation (UVB) is a ubiquitous environmental toxin that causes extensive skin damage resulting in inflammation, photoaging and cancer. UVB is known to induce inflammasome activation and a sterile inflammation associated with cytokine release (e.g. IL-1β, IL-18) and immune cell infiltration. We developed circularly permutated luciferase reporters for caspase-1 activation to assess inflammasome activation by UVB in vitro and in vivo. HaCaT keratinocytes transduced with caspase-1 reporters encoding either the caspase-7 or Gasdermin D cleavage sequence became active after exposure to UVB, with maximum caspase-1 activation 9 hours post-UVB with 15 mJ/cm2.