Xiwei Wang1, Wenwei Tu2. 1. Laboratory for Medical Translational Immunology, Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, SAR, China. 2. Laboratory for Medical Translational Immunology, Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, SAR, China. wwtu@hku.hk.