title: Transcutaneous vaccines--current and emerging strategies.
abstract: BACKGROUND
  Vaccination, which is the major fundamental prophylaxis against illness and death from infectious disease, has greatly contributed to the global improvement of human health. However, the disadvantages of conventional injection systems hamper the delivery of vaccination technologies to developing countries. The imminent practice of easy-to-use vaccination methods is expected to overcome certain issues associated with injectable vaccinations. One innovative method is the transcutaneous immunization (TCI) system.
  
  
  METHODS
  Two major strategies for TCI are discussed in this review. One is to promote antigen permeation of the skin barrier by patch systems or nanoparticles. The other is the delivery of antigens into the skin by electroporation and microneedles in order to physically overcome the skin barrier. Moreover, adjuvant development for TCI is discussed.
  
  
  CONCLUSIONS
  Many different approaches have been developed for TCI, which have the potential to be effective, easy-to-use and painless methods of vaccination. However, in practical terms, the guidelines concerning the manufacturing processes and clinical trial evaluation of the procedures have not kept pace with the development of these novel formulations. The accumulation of information regarding skin characteristics and the properties of TCI devices will help refine TCI system development guidelines and thus lead to the improvement of transcutaneous vaccination.
authors: Osaka University, Graduate School of Pharmaceutical Sciences, Laboratory of Biotechnology and Therapeutics, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Sachiko
authors: S
authors: Hirobe
authors: Naoki
authors: N
authors: Okada
authors: Shinsaku
authors: S
authors: Nakagawa
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000279:Administration, Cutaneous; D000818:Animals; D000941:Antigens / Q000008:administration & dosage / Q000276:immunology; D002626:Chemistry, Pharmaceutical; D003906:Developing Countries; D018274:Electroporation; D006801:Humans; D007114:Immunization / Q000379:methods; D053758:Nanoparticles / Q000008:administration & dosage; D012867:Skin / Q000276:immunology; D013678:Technology, Pharmaceutical / Q000639:trends*; D057968:Transdermal Patch; D014611:Vaccination / Q000379:methods*; D014612:Vaccines / Q000008:administration & dosage*
chemical_list: D000276:Adjuvants, Immunologic; D000941:Antigens; D014612:Vaccines