TLR3 and dermatitis: TLR3 is expressed in the epidermis of the skin and it positively regulates skin inflammation (Nakamura et al., 2015; Yasuike et al., 2017), and it is possible that innate immunity such as TLR3 might contribute to mucocutaneous inflammation seen in SJS/TEN with SOC (Ueta and Kinoshita, 2012; Ueta, 2016; Ueta, 2018; Ueta, 2021a).