1. Department of Stem Cell Biology, Konkuk University School of Medicine, Seoul, Korea
2. Center for Stem Cell Research, Institute of Advanced Biomedical Science, Konkuk University, Seoul, Korea
3. Viral Disease Division, Animal and Plant Quarantine Agency, Gimcheon, Korea
4. Department of Medicine, College of Medicine, Chung-Ang University, Seoul, Korea
5. Research Institute of Medical Science, Konkuk University, Seoul, Korea