title: Transcutaneous delivery of CpG-adjuvanted allergen via laser-generated micropores.
abstract: BACKGROUND
  Two main shortcomings of classical allergen-specific immunotherapy are long treatment duration and low patient compliance. Utilizing the unique immunological features of the skin by transcutaneous application of antigen opens new approaches not only for painless vaccine delivery, but also for allergen-specific immunotherapy. Under certain conditions, however, barrier disruption of the skin favors T helper 2-biased immune responses, which may lead to new sensitizations.
  
  
  METHODS
  In a prophylactic approach, an infra-red laser device was employed, producing an array of micropores of user-defined number, density, and depth on dorsal mouse skin. The grass pollen allergen Phl p 5 was administered by patch with or without the T helper 1-promoting CpG oligodeoxynucleotide 1826 as adjuvant, or was subcutaneously injected. Protection from allergic immune responses was tested by sensitization via injection of allergen adjuvanted with alum, followed by intranasal instillation. In a therapeutic setting, pre-sensitized mice were treated either by the standard method using subcutaneous injection or via laser-generated micropores. Sera were analyzed for IgG antibody subclass distribution by ELISA and for IgE antibodies by a basophil mediator release assay. Cytokine profiles from supernatants of re-stimulated lymphocytes and from bronchoalveolar lavage fluids were assessed by flow cytometry using a bead-based assay. The cellular composition of lavage fluids was determined by flow cytometry.
  
  
  RESULTS
  Application of antigen via micropores induced T helper 2-biased immune responses. Addition of CpG balanced the response and prevented from allergic sensitization, i.e. IgE induction, airway inflammation, and expression of T helper 2 cytokines. Therapeutic efficacy of transcutaneous immunotherapy was equal compared to subcutaneous injection, but was superior with respect to suppression of already established IgE responses.
  
  
  CONCLUSIONS
  Transcutaneous immunotherapy via laser-generated micropores provides an efficient novel platform for treatment of type I allergic diseases. Furthermore, immunomodulation with T helper 1-promoting adjuvants can prevent the risk for new sensitization.
authors.affiliation: Department of Molecular Biology, Division of Allergy & Immunology, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Hessenberger
authors.forename: Richard
authors.initials: R
authors.lastname: Weiss
authors.forename: Esther E
authors.initials: EE
authors.lastname: Weinberger
authors.forename: Christof
authors.initials: C
authors.lastname: Boehler
authors.forename: Josef
authors.initials: J
authors.lastname: Thalhamer
authors.forename: Sandra
authors.initials: S
authors.lastname: Scheiblhofer
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000279:Administration, Cutaneous; D000485:Allergens / Q000008:administration & dosage* / Q000276:immunology; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D016207:Cytokines / Q000276:immunology; D003888:Desensitization, Immunologic / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay; D004804:Eosinophils / Q000276:immunology; D005260:Female; D007114:Immunization / Q000379:methods; D007073:Immunoglobulin E / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007249:Inflammation / Q000276:immunology; D007834:Lasers; D008214:Lymphocytes / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D009838:Oligodeoxyribonucleotides / Q000494:pharmacology*; D006109:Poaceae; D011058:Pollen / Q000276:immunology; D057968:Transdermal Patch
chemical_list: D000276:Adjuvants, Immunologic; D000485:Allergens; C423449:CpG ODN 1826; D016207:Cytokines; D007074:Immunoglobulin G; D009838:Oligodeoxyribonucleotides; D007073:Immunoglobulin E