1. Institute of Infectious Disease and Vaccinology, National Health Research Institutes, Zhunan Town, Miaoli County 350, Taiwan
2. Graduate School of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan
3. Graduate Program of Biotechnology in Medicine, Institute of Molecular Medicine, National Tsing Hua University, Hsinchu 300, Taiwan
4. Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu 300, Taiwan
5. Graduate Institute of Biomedical Sciences, China Medical University, Taichung 404, Taiwan