1. Department of Dermatology, The Jikei University School of Medicine, 3‐25‐8 Nishi‐shimbashi, Minato‐ku, Tokyo 105‐8461, Japan
2. Department of Otolaryngology, Japanese Red Cross Medical Center, Shibuya‐ku, Tokyo 150‐8935, Japan
Department of Pathology and
3. Laboratory of Tumor Viruses, Department of Virology II, National Institute of Infectious Diseases,
1‐23‐1 Toyama, Shinjuku‐ku, Tokyo 162‐8640, Japan