title: Lipidated L2 epitope repeats fused with a single-chain antibody fragment targeting human FcγRI elicited cross-neutralizing antibodies against a broad spectrum of human papillomavirus types.
abstract: Numerous types of human papillomaviruses (HPVs) have been identified, and the global burden of diseases associated with HPV infection is remarkable, especially in developing regions. Thus a low-cost broad-spectrum prophylactic vaccine is urgently needed. The N-terminal amino acid 17-36 of HPV 16 L2 protein is confirmed to be a major cross-neutralizing epitope (RG-1 epitope). Monomeric proteins containing RG-1 epitopes and scaffold proteins, such as bacterial thioredoxin or modified IgG1 Fc fragment and L2 epitope fusion protein, induced cross-neutralizing antibodies, arousing the possibility of the development of low-cost monomeric vaccine in bacterial expression system. Here we show that a novel immunogen-scaffold protein containing a lipidated triple-repeat HPV 16RG-1 epitope and a hFcγRI specific single-chain antibody fragment (H22scFv), named LpE3H22, elicited high titers of cross-neutralizing antibodies against a broad range of mucosal and cutaneous HPV types when adjuvanted with MF59 and poly I:C. LpE3H22 was produced in E. coli expression system. In contrast to three repeats of RG-1 epitope (E3) and unlipidated fusion protein E3H22, vaccination of LpE3H22 induced robust cross-neutralizing antibody responses in hFcγRI transgenic mice. Furthermore, the neutralizing antibody response induced by LpE3H22 was significantly weaker in WT mice than in the Tg mice. The cross-neutralizing antibodies induced by LpE3H22 sustained for at least 10months in Tg mice. Our results demonstrate that hFcγRI targeting and lipidation both contribute to the enhancement of immunogenicity of L2 antigen. Therefore, delivering the lipidated L2 antigen with H22scFv opens a new avenue for low-cost pan-HPV vaccine development.
authors.affiliation: Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China.
authors.forename: Hongyang
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China.
authors.forename: Zhirong
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Molecular Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Qu
authors.affiliation: Changchun Werersai Biotec Pharmaceutical Co., LTD, Changchun, China.
authors.forename: Jingzhi
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China. Electronic address: xuemeixu@vip.sina.com.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Xu
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000096:biosynthesis* / Q000276:immunology; D036022:Capsid Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology*; D056738:Cross Protection; D000939:Epitopes / Q000276:immunology; D006801:Humans; D000071497:Immunogenicity, Vaccine; D007141:Immunoglobulin Fc Fragments / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009856:Oncogene Proteins, Viral / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology*; D027383:Papillomaviridae / Q000737:chemistry / Q000276:immunology; D030361:Papillomavirus Infections / Q000276:immunology / Q000517:prevention & control; D053918:Papillomavirus Vaccines / Q000008:administration & dosage / Q000276:immunology*; D017452:Receptors, IgG / Q000276:immunology*; D058425:Vaccines, Virus-Like Particle / Q000276:immunology
chemical_list: D057134:Antibodies, Neutralizing; D036022:Capsid Proteins; D000939:Epitopes; D007141:Immunoglobulin Fc Fragments; C063316:L2 protein, Human papillomavirus type 16; D009856:Oncogene Proteins, Viral; D053918:Papillomavirus Vaccines; D017452:Receptors, IgG; D058425:Vaccines, Virus-Like Particle
keywords: L2; Lipoprotein; Papillomavirus; hFcγRI targeting