1. Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, South Korea
2. BK 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
3. Research Center for Natural Human Defense System, Yonsei University College of Medicine, Seoul, South Korea
4. The Airway Mucus Institute, Yonsei University College of Medicine, Seoul, South Korea