title: Concatenated multitype L2 fusion proteins as candidate prophylactic pan-human papillomavirus vaccines.
abstract: BACKGROUND
  Vaccination with minor capsid protein L2 induces antibodies that cross-neutralize diverse papillomavirus types. However, neutralizing antibody titers against the papillomavirus type from which the L2 vaccine was derived are generally higher than the titers against heterologous types, which could limit effectiveness against heterologous types. We hypothesized that vaccination with concatenated multitype L2 fusion proteins derived from known cross-protective epitopes of several divergent human papillomavirus (HPV) types might enhance immunity across clinically relevant HPV genotypes.
  
  
  METHODS
  Antibody responses of mice (n = 120) and rabbits (n = 23) to vaccination with HPV-16 amino-terminal L2 polypeptides or multitype L2 fusion proteins, namely, 11-200 x 3 (HPV types 6, 16, 18), 11-88 x 5 (HPV types 1, 5, 6, 16, 18), or 17-36 x 22 (five cutaneous, two mucosal low-risk, and 15 oncogenic types), that were formulated alone or in GPI-0100, alum, or 1018 ISS adjuvants were compared with vaccination with L1 virus-like particles (VLPs), including Gardasil, a licensed quadrivalent HPV L1 vaccine, and a negative control. Mice were challenged with HPV-16 pseudovirions 4 months after vaccination. Statistical tests were two-sided.
  
  
  RESULTS
  The HPV-16 L2 polypeptides generated robust HPV-16-neutralizing antibody responses, albeit lower than those to HPV-16 L1 VLPs, and lower responses against other HPVs. In contrast, vaccination with the multitype L2 fusion proteins 11-200 x 3 and 11-88 x 5 induced high serum neutralizing antibody titers against all heterologous HPVs tested. 11-200 x 3 formulated in GPI-0100 adjuvant or alum with 1018 ISS protected mice against HPV-16 challenge (reduction in HPV-16 infection vs phosphate-buffered saline control, P < .001) 4 months after vaccination as well as HPV-16 L1 VLPs, but 11-200 x 3 alone or formulated with either alum or 1018 ISS was less effective (reduction in HPV-16 infection, P < .001).
  
  
  CONCLUSIONS
  Concatenated multitype L2 proteins in adjuvant have potential as pan-oncogenic HPV vaccines.
authors.affiliation: Department of Pathology, The Johns Hopkins University, Baltimore, MD 21231, USA.
authors.forename: Subhashini
authors.initials: S
authors.lastname: Jagu
authors.forename: Balasubramanyam
authors.initials: B
authors.lastname: Karanam
authors.forename: Ratish
authors.initials: R
authors.lastname: Gambhira
authors.forename: Sudha V
authors.initials: SV
authors.lastname: Chivukula
authors.forename: Revathi J
authors.initials: RJ
authors.lastname: Chaganti
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Lowy
authors.forename: John T
authors.initials: JT
authors.lastname: Schiller
authors.forename: Richard B S
authors.initials: RB
authors.lastname: Roden
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000097:blood / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D036022:Capsid Proteins / Q000276:immunology* / Q000627:therapeutic use; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology; D005260:Female; D000068857:Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18; D052162:Human papillomavirus 16 / Q000276:immunology*; D006801:Humans; D007106:Immune Sera; D051379:Mice; D008807:Mice, Inbred BALB C; D009500:Neutralization Tests / Q000379:methods; D009856:Oncogene Proteins, Viral / Q000276:immunology* / Q000627:therapeutic use; D030361:Papillomavirus Infections / Q000150:complications / Q000517:prevention & control* / Q000821:virology; D053918:Papillomavirus Vaccines / Q000276:immunology* / Q000627:therapeutic use; D011817:Rabbits; D013997:Time Factors; D014771:Virion
chemical_list: D000914:Antibodies, Viral; D036022:Capsid Proteins; D000939:Epitopes; D000068857:Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18; D007106:Immune Sera; C063316:L2 protein, Human papillomavirus type 16; D009856:Oncogene Proteins, Viral; D053918:Papillomavirus Vaccines