1. School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031, People’s Republic of China
2. Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, KU Leuven, Herestraat 49, Box 1043, 3000 Leuven, Belgium