1 Department of Allergy and Clinical Immunology, Graduate School of Medicine, Chiba University, Chiba, Japan.
2 Department of Immunology, Graduate School of Medicine, Chiba University, Chiba, Japan.
3 Department of Allergy and Clinical Immunology, Graduate School of Medicine, Chiba University, Chiba, Japan. Electronic address: t.kageyama@chiba-u.jp.
4 Department of Allergy and Clinical Immunology, Graduate School of Medicine, Chiba University, Chiba, Japan; Chiba University Synergy Institute for Futuristic Mucosal Vaccine Research and Development (cSIMVa), Chiba, Japan. Electronic address: nakajimh@faculty.chiba-u.jp.