Age-Specific Profiles of Antibody Responses against Respiratory Syncytial Virus Infection
Nao Jounai,
Megumi Yoshioka,
Miyuki Tozuka,
Kazue Inoue,
Tatsuya Oka,
Kazuki Miyaji,
Katsuyasu Ishida,
Naoki Kawai,
Hideyuki Ikematsu,
Chiaki Kawakami,
Hiroyuki Shimizu,
Masaaki Mori,
Ken J. Ishii,
Fumihiko Takeshita
Affiliations
Nao Jounai
Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan
Megumi Yoshioka
Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan
Miyuki Tozuka
Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan
Kazue Inoue
Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan
Tatsuya Oka
Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan
Kazuki Miyaji
Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan
Katsuyasu Ishida
Daiichi Sankyo Co., Ltd., 3-5-1 Nihonbashi Honcho, Chuo-ku, Tokyo 103-8426, Japan
Naoki Kawai
Japan Physicians Association, 2-5 Kanda Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan
Hideyuki Ikematsu
Japan Physicians Association, 2-5 Kanda Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan
Chiaki Kawakami
Department of Pediatrics, Yokosuka Kyosai Hospital, 1-16 Yonegahamadori, Yokosuka, Kanagawa 238-8558, Japan
Hiroyuki Shimizu
Children's Medical Center, Yokohama City University Medical Center, 4-57 Urafune, Minami-ku, Yokohama, Kanagawa 232-0024, Japan
Masaaki Mori
Department of Lifetime Clinical Immunology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
Ken J. Ishii
Laboratory of Adjuvant Innovation, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki City, Osaka 567-0085, Japan
Fumihiko Takeshita
Daiichi Sankyo Co., Ltd., 3-5-1 Nihonbashi Honcho, Chuo-ku, Tokyo 103-8426, Japan
Respiratory syncytial virus (RSV) is one of the most prevalent causative agents of lower respiratory tract infections worldwide, especially in infants around 3 to 4 months old. Infants at such a young age have maternally-transferred passive antibodies against RSV but do not have active immune systems efficient enough for the control of RSV infection. In order to elucidate age-specific profiles of immune responses against RSV protection, antibody responses were examined by using blood samples in both acute and convalescent phases obtained from child patients and adult patients. In addition to the serum neutralization activity, antibody responses to the RSV fusion protein (F protein) were dissected by analyzing levels of total IgG, IgG subclasses, the binding stability, and the levels of antibody for the neutralization epitopes. It was suggested that children's antibody responses against RSV are matured over months and years in at least 5 stages based on 1) levels of the neutralization titer and IgG3 for F protein in the convalescent phase, 2) geometric mean ratios of the neutralization titers and levels of IgG1 and IgG2 for F protein in the convalescent phase compared to those levels in the acute phase, 3) the affinity maturation of IgG for F protein and the cross reactivity of IgG for RSV glycoproteins of groups A and B, 4) levels of neutralization epitope-specific IgG, and 5) augmentation of overall antibody responses due to repetitive RSV infection.
