Jie Liu is a Professor at Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, State Key Laboratory of Complex Severe and Rare Diseases, National Clinical Research Center for Dermatologic and Immunologic Diseases, Beijing, China. Xian-biao Zou is a Professor at Department of Dermatology, South China Hospital, Health Science Center, Shenzhen University, Shenzhen, China.