title: Modulation of allergic immune responses by mucosal application of recombinant lactic acid bacteria producing the major birch pollen allergen Bet v 1.
abstract: BACKGROUND
  Probiotic lactic acid bacteria (LAB) are able to modulate the host immune system and clinical trials have demonstrated that specific strains have the capacity to reduce allergic symptoms. Therefore, we aimed to evaluate the potential of recombinant LAB producing the major birch pollen allergen Bet v 1 for mucosal vaccination against birch pollen allergy.
  
  
  METHODS
  Recombinant Bet v 1-producing Lactobacillus plantarum and Lactococcus lactis strains were constructed. Their immunogenicity was compared with purified Bet v 1 by subcutaneous immunization of mice. Intranasal application of the live recombinant strains was performed to test their immunomodulatory potency in a mouse model of birch pollen allergy.
  
  
  RESULTS
  Bet v 1 produced by the LAB was recognized by monoclonal anti-Bet v 1 and IgE antibodies from birch pollen-allergic patients. Systemic immunization with the recombinant strains induced significantly lower IgG1/IgG2a ratios compared with purified Bet v 1. Intranasal pretreatment led to reduced allergen-specific IgE vs enhanced IgG2a levels and reduced interleukin (IL)-5 production of splenocytes in vitro, indicating a shift towards non-allergic T-helper-1 (Th1) responses. Airway inflammation, i.e. eosinophils and IL-5 in lung lavages, was reduced using either Bet v 1-producing or control strains. Allergen-specific secretory IgA responses were enhanced in lungs and intestines after pretreatment with only the Bet v 1-producing strains.
  
  
  CONCLUSIONS
  Mucosal vaccination with live recombinant LAB, leading to a shift towards non-allergic immune responses along with enhanced allergen-specific mucosal IgA levels offers a promising approach to prevent systemic and local allergic immune responses.
authors.affiliation: Laboratoire de Bactériologie des Ecosystèmes, Institut Pasteur de Lille, Lille Cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: Daniel
authors.forename: A
authors.initials: A
authors.lastname: Repa
authors.forename: C
authors.initials: C
authors.lastname: Wild
authors.forename: A
authors.initials: A
authors.lastname: Pollak
authors.forename: B
authors.initials: B
authors.lastname: Pot
authors.forename: H
authors.initials: H
authors.lastname: Breiteneder
authors.forename: U
authors.initials: U
authors.lastname: Wiedermann
authors.forename: A
authors.initials: A
authors.lastname: Mercenier
mesh_terms: D000281:Administration, Intranasal; D000485:Allergens / Q000235:genetics / Q000276:immunology*; D000818:Animals; D052179:Antigens, Plant; D001249:Asthma / Q000276:immunology / Q000517:prevention & control*; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D003888:Desensitization, Immunologic; D004195:Disease Models, Animal; D018928:Immunity, Mucosal; D007070:Immunoglobulin A / Q000097:blood; D007073:Immunoglobulin E / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007371:Interferon-gamma / Q000276:immunology; D015848:Interleukin-5 / Q000276:immunology; D007421:Intestine, Small / Q000276:immunology; D048191:Lactiplantibacillus plantarum / Q000235:genetics / Q000276:immunology*; D013294:Lactococcus lactis / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010940:Plant Proteins / Q000235:genetics / Q000276:immunology*; D011058:Pollen / Q000235:genetics / Q000276:immunology; D014612:Vaccines / Q000627:therapeutic use*
chemical_list: D000485:Allergens; D052179:Antigens, Plant; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D015848:Interleukin-5; D010940:Plant Proteins; D014612:Vaccines; C061312:Bet v 1 allergen, Betula; D007073:Immunoglobulin E; D007371:Interferon-gamma