Cutaneous lupus erythematosus (CLE) and dermatomyositis are photosensitive diseases, in which ultraviolet (UV) light causes inflammation, but the underlying mechanisms that mediate this process remain unclear. Now, findings published in Nature Immunology provide insights into the link between UV exposure and skin inflammation.

The co-corresponding author of this article Mehdi Rashighi explains the study rationale: “Our prior work, together with studies from others in inflammatory skin disease, suggested that clinically normal-appearing, non-lesional skin is not necessarily immunologically normal … which raised an important conceptual question … could clinically unaffected skin in patients with CLE or dermatomyositis already be primed to respond abnormally to environmental triggers such as UV radiation?”