Ha Zhu1,2, Xuetao Cao1,2,3. 1. Institute of Immunology, Zhejiang University School of Medicine, Hangzhou 310058, China. 2. National Key Laboratory of Medical Immunology & Institute of Immunology, Second Military Medical University, Shanghai 200433, China. 3. Department of Immunology & Center for Immunotherapy, Institute of Basic Medical Sciences, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100005, China.