Sarkar MK, et al. - Authors gauged the role of interferon kappa (IFN-κ) in regulation of type I interferon (IFN) and photosensitive responses and evaluated its dysregulation in lupus skin. Collectively, in cutaneous lupus erythematosus (CLE) pathology IFN-κ was identified as a critical IFN via promotion of enhanced IFN responses and photosensitivity. For UVB prophylaxis and CLE-directed therapy, IFN-κ is a potential novel target. The responsiveness of epithelia to IFN-α was amplified and accelerated with the increased levels of IFN-κ, such as seen in SLE and it increased the keratinocyte sensitivity to UV irradiation.