title: Identification of Broad-Genotype HPV L2 Neutralization Site for Pan-HPV Vaccine Development by a Cross-Neutralizing Antibody.
abstract: Human Papillomavirus (HPV), a non-enveloped, double-stranded DNA virus, is responsible for 5% of human cancers. The HPV capsid consists of major and minor structural proteins, L1 and L2. L1 proteins form an icosahedral shell with building blocks of the pentameric capsomere, and one L2 molecule extends outward from the central hole of the capsid. Thus, L2 is concealed within L1 and only becomes exposed when the capsid interacts with host cells. The low antigenic variation of L2 means that this protein could offer a target for the development of a pan-HPV vaccine. Toward this goal, here we describe an anti-L2 monoclonal antibody, 14H6, which broadly neutralizes at least 11 types of HPV, covering types 6, 11, 16, 18, 31, 33, 35, 45, 52, 58 and 59, in pseudovirion--based cell neutralization assay. The mAb 14H6 recognizes a minimal linear epitope located on amino acids 21 to 30 of the L2 protein. Alanine scanning mutagenesis and sequence alignment identified several conserved residues (Cys22, Lys23, Thr27, Cys28 and Pro29) that are involved in the 14H6 binding with L2. The epitope was grafted to several scaffolding proteins, including HPV16 L1 virus-like particles, HBV 149 core antigen and CRM197. The resultant chimeric constructs were expressed in Escherichia coli and purified with high efficiency. Immunization with these pan-HPV vaccine candidates elicited high titers of the L2-specific antibody in mice and conferred robust (3-log) titers of cross-genotype neutralization, including against HPV11, 16, 18, 45, 52, 58 and 59. These findings will help in the development of an L2-based, pan-HPV vaccine.
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, 361005, China.
authors.forename: Daning
authors.initials: D
authors.lastname: Wang
authors.affiliation: National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Life Sciences, Xiamen University, Xiamen, 361005, China.
authors.forename: Zhihai
authors.initials: Z
authors.lastname: Li
authors.affiliation: National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Life Sciences, Xiamen University, Xiamen, 361005, China.
authors.forename: Jieqiong
authors.initials: J
authors.lastname: Xiao
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, 361005, China.
authors.forename: Junqi
authors.initials: J
authors.lastname: Wang
authors.affiliation: National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Life Sciences, Xiamen University, Xiamen, 361005, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Life Sciences, Xiamen University, Xiamen, 361005, China.
authors.forename: Yajing
authors.initials: Y
authors.lastname: Liu
authors.affiliation: National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Life Sciences, Xiamen University, Xiamen, 361005, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, 361005, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Xin
authors.affiliation: National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Life Sciences, Xiamen University, Xiamen, 361005, China.
authors.forename: Minxi
authors.initials: M
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, 361005, China.
authors.forename: Zhibo
authors.initials: Z
authors.lastname: Kong
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, 361005, China.
authors.forename: Hai
authors.initials: H
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, 361005, China; National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Life Sciences, Xiamen University, Xiamen, 361005, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Gu
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, 361005, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, 361005, China; National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Life Sciences, Xiamen University, Xiamen, 361005, China.
authors.forename: Shaowei
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, 361005, China; National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Life Sciences, Xiamen University, Xiamen, 361005, China.
authors.forename: Ningshao
authors.initials: N
authors.lastname: Xia
mesh_terms: D052685:Alphapapillomavirus / Q000235:genetics* / Q000276:immunology*; D000818:Animals; D057134:Antibodies, Neutralizing / Q000276:immunology*; D018604:Epitope Mapping; D005838:Genotype; D051379:Mice; D008807:Mice, Inbred BALB C; D014764:Viral Proteins / Q000737:chemistry / Q000276:immunology; D014765:Viral Vaccines / Q000276:immunology*
chemical_list: D057134:Antibodies, Neutralizing; D014764:Viral Proteins; D014765:Viral Vaccines