1. Department of Dermatology; The Second Affiliated Hospital of Xi'an Jiaotong University; Xi'an 710004 China
2. Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology; University of California; San Francisco CA USA
3. Key Laboratory of Immune Microenvironment and Disease (Ministry of State Education), Immunology Department; Tianjin Medical University; Tianjin 300070 China