title: [Expression, purification and immunogenicity of human papillomavirus type 11 virus-like particles from Escherichia coli].
abstract: OBJECTIVE
  To produce human papillomavirus type 11 virus-like particles (HPV11 VLPs) from Escherichia coli and to investigate its immunogenicity and type cross neutralization nature.
  
  
  METHODS
  We expressed the major capsid protein of HPV11 (HPV11-L1) in Escherichia coli ER2566 in non fusion fashion and purified by amino sulfate precipitation, ion-exchange chromatography and hydrophobic interaction chromatography, sequentially. Then we removed the reductant DTT to have the purified HPV11-L1 self-assemble into VLPs in vitro. We investigated the morphology of these VLPs with dynamic light scattering and transmission electron microscopy. We assayed the immunogenicity of the resultant HPV11 VLPs by vaccinations on mice and evaluated by HPV6/11/16/18 pseudovirion neutralization cell models.
  
  
  RESULTS
  We expressed HPV11 L1 in Escherichia coli with two forms, soluble and inclusion body. The soluble HPV11 L1 with over 95% purity can self assemble to VLPs in high efficiency. Morphologically, these VLPs were globular, homogeneous and with a diameter of - 50 nm, which is quite similar with native HPV11 virions. The half effective dosage (ED50) of HPV11 VLPs is 0.031 microg, and the maximum titer of neutralizing antibody elicited is averaged to 10(6). The cross neutralization activity (against HPV6/16/18) of the anti-HPV11 serum was found to have exact correlation to the inter-type homology in amino acid alignment.
  
  
  CONCLUSIONS
  We can provide HPV11 VLPs with highly immunogenicity from prokaryote expression system, which may pave a new way for research and development of prophylactic vaccine for HPV11.
authors.affiliation: National Institute of Diagnostics and Vaccine Development in infectious diseases, Life Science School, Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, Xiamen University, Xiamen 361005, China. yangchunyan@xmu.edu.cn
authors.forename: Chunyan
authors.initials: C
authors.lastname: Yan
authors.forename: Shaowei
authors.initials: S
authors.lastname: Li
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Minxi
authors.initials: M
authors.lastname: Wei
authors.forename: Bo
authors.initials: B
authors.lastname: Huang
authors.forename: Yudi
authors.initials: Y
authors.lastname: Zhuang
authors.forename: Zhongyi
authors.initials: Z
authors.lastname: Li
authors.forename: Huirong
authors.initials: H
authors.lastname: Pan
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: Ningshao
authors.initials: N
authors.lastname: Xia
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D036022:Capsid Proteins / Q000276:immunology* / Q000302:isolation & purification* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D052140:Human papillomavirus 11 / Q000145:classification / Q000235:genetics / Q000276:immunology*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D030361:Papillomavirus Infections / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D053918:Papillomavirus Vaccines / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D010802:Phylogeny; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D014771:Virion / Q000145:classification / Q000235:genetics / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D036022:Capsid Proteins; D053918:Papillomavirus Vaccines; D011994:Recombinant Proteins