Immunoproteomic identification of the hypothetical protein NMB1468 as a novel lipoprotein ubiquitous in Neisseria meningitidis with vaccine potential.
Many potential vaccine candidates for serogroup B Neisseria meningitidis (NMB) have been identified by reverse vaccinology, a genome-based approach. However, some candidates may be unseen owing to uncertain annotation or their peculiar properties. In this study, we describe the preparation and identification of a novel lipoprotein expressed in all meningococcal strains tested. mAb were first prepared from mice immunized with a meningococcal B strain isolated in Taiwan. Total proteins from the immunizing strain were separated by 2-DE in duplicate. Clone 4-7-3, which crossreacted to 174 tested meningococcal isolates, was used as the primary antibody for Western blotting. The immunoreactive spot was identified by LC-mass spectrometric analysis of the corresponding spot from the silver-stained gel and confirmed by molecular biology approach to be a novel lipoprotein encoded by the hypothetical NMB1468 gene. The potential use of this protein, designated Ag473/NMB1468, as a vaccine component was evaluated using the recombinant protein produced in Escherichia coli. Immunized mice were found to be protected from developing meningococcal disease after intraperitoneal inoculation with a lethal dose of meningococcal strain Nm22209, suggesting that Ag473/NMB1468 may be a promising vaccine candidate. This study also demonstrates the usefulness of the immunoproteomic approach in identification of novel vaccine candidates.
Hsu
Chi-An
CA
Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan.
Lin
Wei-Ru
WR
Li
Jung-Chen
JC
Liu
Yi-Lung
YL
Tseng
Yen-Tzu
YT
Chang
Chun-Mien
CM
Lee
Yeong-Sheng
YS
Yang
Chiou-Ying
CY
D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D001428:Bacterial Vaccines / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D015153:Blotting, Western; D015180:Electrophoresis, Gel, Two-Dimensional; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D008074:Lipoproteins / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D022401:Meningococcal Vaccines / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009345:Neisseria meningitidis / Q000276:immunology / Q000378:metabolism*
D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D008074:Lipoproteins; D022401:Meningococcal Vaccines; C530756:NMB1468 protein, Neisseria meningitidis