title: Age-Specific Profiles of Antibody Responses against Respiratory Syncytial Virus Infection.
abstract: Respiratory syncytial virus (RSV) is one of the most prevalent causative agents of lower respiratory tract infections worldwide, especially in infants around 3 to 4months 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.
authors.affiliation: Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan; Laboratory of Adjuvant Innovation, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki City, Osaka 567-0085, Japan.
authors.forename: Nao
authors.initials: N
authors.lastname: Jounai
authors.affiliation: Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan.
authors.forename: Megumi
authors.initials: M
authors.lastname: Yoshioka
authors.affiliation: Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan; Laboratory of Adjuvant Innovation, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki City, Osaka 567-0085, Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Tozuka
authors.affiliation: Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan.
authors.forename: Kazue
authors.initials: K
authors.lastname: Inoue
authors.affiliation: Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Oka
authors.affiliation: Kitasato Daiichi Sankyo Vaccine Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo 134-8630, Japan; Laboratory of Adjuvant Innovation, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki City, Osaka 567-0085, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Miyaji
authors.affiliation: Daiichi Sankyo Co., Ltd., 3-5-1 Nihonbashi Honcho, Chuo-ku, Tokyo 103-8426, Japan.
authors.forename: Katsuyasu
authors.initials: K
authors.lastname: Ishida
authors.affiliation: Japan Physicians Association, 2-5 Kanda Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Kawai
authors.affiliation: Japan Physicians Association, 2-5 Kanda Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ikematsu
authors.affiliation: Department of Pediatrics, Yokosuka Kyosai Hospital, 1-16 Yonegahamadori, Yokosuka, Kanagawa 238-8558, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Kawakami
authors.affiliation: Children's Medical Center, Yokohama City University Medical Center, 4-57 Urafune, Minami-ku, Yokohama, Kanagawa 232-0024, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shimizu
authors.affiliation: 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.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Mori
authors.affiliation: Laboratory of Adjuvant Innovation, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki City, Osaka 567-0085, Japan.
authors.forename: Ken J
authors.initials: KJ
authors.lastname: Ishii
authors.affiliation: Daiichi Sankyo Co., Ltd., 3-5-1 Nihonbashi Honcho, Chuo-ku, Tokyo 103-8426, Japan. Electronic address: takeshita.fumihiko.aw@daiichisankyo.co.jp.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Takeshita
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology*; D045744:Cell Line, Tumor; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D054884:Host-Pathogen Interactions / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D018357:Respiratory Syncytial Virus Infections / Q000097:blood / Q000276:immunology* / Q000821:virology; D018113:Respiratory Syncytial Virus, Human / Q000276:immunology* / Q000502:physiology; D014760:Viral Fusion Proteins / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; C526850:F protein, human respiratory syncytial virus; D007074:Immunoglobulin G; D014760:Viral Fusion Proteins
keywords: F protein; IgG3; Palivizumab-like neutralization antibody; RSV