title: Oral delivery of a probiotic induced changes at the nasal mucosa of seasonal allergic rhinitis subjects after local allergen challenge: a randomised clinical trial.
abstract: OBJECTIVE
  To determine effects of probiotic consumption on clinical and immunological parameters of seasonal allergic rhinitis (SAR) in an out-of-season single nasal allergen challenge.
  
  
  METHODS
  In a study registered at ClinicalTrials.Gov (NCT01123252), a 16-week dietary intervention was undertaken in 60 patients with allergic rhinitis (>16 years old). Using a double-blinded, placebo-controlled anonymised design, the patients were divided equally into two groups. One group was given a dairy drink containing Lactobacillus casei Shirota to ingest daily while the other consumed a similar drink without bacteria. Participants attended the clinic on two consecutive days before the intervention and then again at the end of the study period. On the first day of each 2-day visit, following clinical examination, assessments were made of total nasal symptoms scores and peak nasal inspiratory flow. Nasal scrapings, nasal lavage and blood were collected for laboratory analyses of cellular phenotypes, soluble mediator release and in vitro responses to pollen allergen. These procedures were repeated 24 hours following nasal allergen challenge.
  
  
  RESULTS
  Prior to and following intervention there were no detectable differences between study groups in measured clinical outcome. After intervention, there were differences between groups in their percentages of CD86+ epithelial cells (p = 0.0148), CD86+CD252+ non-epithelial cells (p = 0.0347), sIL-1RII release (p = 0.0289) and IL-1β (p = 0.0224) levels at the nasal mucosa. Delivery of probiotic also suppressed production of sCD23 (p = 0.0081), TGF-β (p = 0.0283) and induced increased production of IFN-γ (p = 0.0351) in supernatants of cultured peripheral blood.
  
  
  CONCLUSIONS
  This study did not show significant probiotic-associated changes with respect to the primary clinical endpoint. An absence of overt clinical benefit may be due to an inability of single nasal challenges to accurately represent natural allergen exposure. Nevertheless, oral delivery of probiotics produced changes of the immunological microenvironment at the nasal mucosa in individuals affected by SAR.
  
  
  BACKGROUND
  ClinicalTrials.Gov NCT01123252.
authors.affiliation: Gut Health and Food Safety Strategic Programme, Institute of Food Research, Colney, Norwich, United Kingdom.
authors.forename: Kamal
authors.initials: K
authors.lastname: Ivory
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Wilson
authors.forename: Prasanna
authors.initials: P
authors.lastname: Sankaran
authors.forename: Marta
authors.initials: M
authors.lastname: Westwood
authors.forename: Justin
authors.initials: J
authors.lastname: McCarville
authors.forename: Claire
authors.initials: C
authors.lastname: Brockwell
authors.forename: Allan
authors.initials: A
authors.lastname: Clark
authors.forename: Jack R
authors.initials: JR
authors.lastname: Dainty
authors.forename: Laurian
authors.initials: L
authors.lastname: Zuidmeer-Jongejan
authors.forename: Claudio
authors.initials: C
authors.lastname: Nicoletti
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000485:Allergens; D015703:Antigens, CD / Q000097:blood / Q000276:immunology; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000097:blood / Q000276:immunology; D053583:Interleukin-1beta / Q000097:blood / Q000276:immunology; D007780:Lacticaseibacillus casei; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D019936:Probiotics / Q000008:administration & dosage*; D006255:Rhinitis, Allergic, Seasonal / Q000097:blood / Q000188:drug therapy* / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000097:blood / Q000276:immunology
chemical_list: D000485:Allergens; D015703:Antigens, CD; C573415:IFNG protein, human; C508585:IL1B protein, human; D053583:Interleukin-1beta; D016212:Transforming Growth Factor beta; D007371:Interferon-gamma