title: Immunomodulatory properties of Lactobacillus plantarum and its use as a recombinant vaccine against mite allergy.
abstract: BACKGROUND
  Selected lactic acid bacteria were reported to prevent atopic dermatitis and experimental asthma but the mechanisms of their immunomodulatory effects are not fully elucidated. In this study, the signaling pathways triggered by Lactobacillus plantarum NCIMB8826 were investigated and the potential use of this strain producing a variant of the mite allergen Der p 1 as live vaccine vehicle was evaluated.
  
  
  METHODS
  Mouse bone marrow-derived dendritic cells were stimulated with wild-type or a L. plantarum teichoic acid mutant to evaluate the secretion of cytokines. A recombinant L. plantarum expressing Der p 1 was engineered, its in vitro immunomodulatory properties were characterized and its prophylactic potential was evaluated in a Der p 1-sensitization murine model.
  
  
  RESULTS
  Mouse dendritic cells stimulated by L. plantarum triggered the release of interleukin-10 (IL-10), IL-12 p40, IL-12 p70 and tumor necrosis factor-alpha (TNF-alpha). IL-12 p40 secretion was dependent on nuclear factor-kappaB (NF-kappaB), mitogen-activated protein (MAP) kinases, Toll-like receptor 2 (TLR2), TLR9 and on the bacterial teichoic acid composition. Recombinant L. plantarum producing Der p 1 exhibited similar immunostimulatory properties as wild-type. Prophylactic intranasal pretreatment of mice with this recombinant strain prevented the development of the typical Th2-biased allergic response by a drastic reduction of specific IgE and the induction of protective allergen-specific IgG2a antibodies. Moreover, both wild-type or recombinant L. plantarum reduced airway eosinophilia following aerosolized allergen exposure and IL-5 secretion upon allergen restimulation.
  
  
  CONCLUSIONS
  By combining both Th1-type immunostimulatory properties and an efficient allergen delivery capacity, recombinant L. plantarum producing Der p 1 represents a promising vaccine against house dust mite allergy.
authors.affiliation: Laboratoire d'Allergologie Expérimentale, Université Libre de Bruxelles, Charleroi, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Rigaux
authors.forename: C
authors.initials: C
authors.lastname: Daniel
authors.forename: M
authors.initials: M
authors.lastname: Hisbergues
authors.forename: E
authors.initials: E
authors.lastname: Muraille
authors.forename: P
authors.initials: P
authors.lastname: Hols
authors.forename: B
authors.initials: B
authors.lastname: Pot
authors.forename: J
authors.initials: J
authors.lastname: Pestel
authors.forename: A
authors.initials: A
authors.lastname: Jacquet
mesh_terms: D000818:Animals; D039741:Antigens, Dermatophagoides / Q000276:immunology*; D060829:Arthropod Proteins; D003546:Cysteine Endopeptidases; D003713:Dendritic Cells / Q000276:immunology; D006801:Humans; D006967:Hypersensitivity / Q000517:prevention & control*; D015151:Immunoblotting; D048191:Lactiplantibacillus plantarum / Q000276:immunology*; D008070:Lipopolysaccharides / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008925:Mites / Q000276:immunology*; D015398:Signal Transduction / Q000276:immunology; D013682:Teichoic Acids / Q000276:immunology; D051195:Toll-Like Receptor 2 / Q000276:immunology; D051217:Toll-Like Receptor 9 / Q000276:immunology; D014162:Transfection; D014614:Vaccines, Synthetic / Q000276:immunology*
chemical_list: D039741:Antigens, Dermatophagoides; D060829:Arthropod Proteins; D008070:Lipopolysaccharides; C495342:TLR2 protein, human; D013682:Teichoic Acids; D051195:Toll-Like Receptor 2; D051217:Toll-Like Receptor 9; D014614:Vaccines, Synthetic; C009900:lipoteichoic acid; D003546:Cysteine Endopeptidases; C451162:Dermatophagoides pteronyssinus antigen p 1