Ultraviolet light induces HERV expression to activate RIG-I signaling pathway in keratinocytes

Skin inflammation and photosensitivity are common in lupus erythematosus (LE) patients, and Ultraviolet (UV) light is a known trigger of skin and possibly systemic inflammation in systemic lupus erythematosus (SLE) and discoid lupus erythematosus (DLE) patients. Type I interferons (IFN) are upregulated in LE skin after UV exposure, however, the mechanisms to explain UVB-induced inflammation remain unclear. Here we performed RNA-seq to HaCat cells with UVB irradiation to characterize gene expression and resolve differential responses of keratinocytes, in order to understand how the keratinocyte response contributes to the disease. Our data showed that HERVs and RIG-I pathway were activated in keratinocytes after UVB exposure and indicate that RIG-I pathway and HERVs are involved in proinflammatory by activating the I-IFN pathway, which provide a novel insight into how UVB promotes and aggravate skin lesion of LE patients. Overall design: mRNA prifules of HaCat cells exposed with or without UVB