title: Transdermal immunization using solid-in-oil nanodispersion with CpG oligodeoxynucleotide adjuvants.
abstract: OBJECTIVE
  Simple and noninvasive vaccine administration alternatives to injections are desired. A solid-in-oil (S/O) nanodispersion system was able to overcome skin barriers and induce an immune response; however, antibody levels remained low. We applied an immune potentiator, CpG oligodeoxynucleotide (ODN), to enhance the immune response by controlling the T helper 1 (Th1)/T helper 2 (Th2) balance.
  
  
  METHODS
  S/O nanodispersions containing ovalbumin (OVA) and CpG ODN (CpG-A or CpG-B) were characterized by size distribution analysis and a protein release test. The skin permeation of fluorescence-labeled OVA was observed by fluorescence microscopy. Antigen-specific IgG, IgG1, and IgG2a responses were measured by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Co-encapsulation of CpG ODNs in S/O nanodispersions enhanced induction of OVA-specific IgG. S/O nanodispersion containing OVA and CpG-A had a smaller mean particle size and permeated the skin more efficiently. In contrast, CpG-B showed the highest protein release and induction of OVA-specific IgG. IgG subclass analysis revealed that OVA induced a Th2-dominant immune response, while the S/O nanodispersion containing CpG-A skewed the immune response toward a Th1-bias.
  
  
  CONCLUSIONS
  In combination with CpG ODN, the S/O nanodispersion system efficiently induced an antigen-specific antibody response. The Th1/Th2 immune balance could be controlled by the selection of CpG ODN type.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, 819-0395, Fukuoka, Japan.
authors.forename: Momoko
authors.initials: M
authors.lastname: Kitaoka
authors.forename: Ayaka
authors.initials: A
authors.lastname: Naritomi
authors.forename: Yuya
authors.initials: Y
authors.lastname: Hirakawa
authors.forename: Noriho
authors.initials: N
authors.lastname: Kamiya
authors.forename: Masahiro
authors.initials: M
authors.lastname: Goto
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000279:Administration, Cutaneous; D000818:Animals; D004655:Emulsions; D007114:Immunization / Q000379:methods*; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008815:Mice, Inbred Strains; D053758:Nanoparticles / Q000737:chemistry*; D009838:Oligodeoxyribonucleotides / Q000008:administration & dosage* / Q000276:immunology; D010047:Ovalbumin / Q000008:administration & dosage* / Q000276:immunology; D014612:Vaccines / Q000008:administration & dosage* / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; C408982:CPG-oligonucleotide; D004655:Emulsions; D007074:Immunoglobulin G; D009838:Oligodeoxyribonucleotides; D014612:Vaccines; D010047:Ovalbumin