title: Expression of activated Fc gamma RII discriminates between multiple granulocyte-priming phenotypes in peripheral blood of allergic asthmatic subjects.
abstract: BACKGROUND
  Allergic asthma is associated with chronic airway and systemic immune responses. Systemic responses include priming of peripheral blood eosinophils, which is enhanced after allergen challenge. In a subpopulation of asthmatic subjects, neutrophils are associated with bronchial inflammation.
  
  
  OBJECTIVE
  We sought to monitor systemic granulocyte priming in allergic asthmatic subjects as a consequence of chronic and acute inflammatory signals initiated by allergen challenge.
  
  
  METHODS
  Blood was taken at baseline and 6 to 24 hours after allergen challenge in asthmatic subjects with and without late asthmatic responses. Systemic granulocyte priming was studied by using expression of cellular markers, such as alpha-chain of Mac-1 (alpha m)/CD11b, L-selectin/CD62L, and an activation epitope present on Fc gamma RII/CD32 recognized by monoclonal phage antibody A17.
  
  
  RESULTS
  Eosinophils of asthmatic subjects have a primed phenotype identified by cell-surface markers. Neutrophils of these patients were subtly primed, which was only identified after activation with N-formyl-methionyl-leucyl-phenylalanine. After allergen challenge, an acute increase in eosinophil priming characterized by enhanced expression of activated Fc gamma RII was found in patients experiencing a late asthmatic response and not in patients with a single early asthmatic response. In contrast, expression of alpha m/CD11b and L-selectin on granulocytes was not different between control and asthmatic subjects and was not affected by allergen challenge. Interestingly, expression of both adhesion molecules was positively correlated, and alpha m expression on eosinophils and neutrophils correlated positively with bronchial hyperresponsiveness.
  
  
  CONCLUSIONS
  Different phases, phenotypes, or both of allergic asthma are associated with distinct priming profiles of inflammatory cells in peripheral blood.
  
  
  CONCLUSIONS
  Insight in differences of systemic innate responses will lead to better definition of asthma subtypes and to better designs of new therapeutic options.
authors: Department of Pulmonary Diseases, University Medical Center Utrecht (UMCU), Utrecht, The Netherlands.
authors: Deon
authors: D
authors: Kanters
authors: Willem
authors: W
authors: ten Hove
authors: Bart
authors: B
authors: Luijk
authors: Corneli
authors: C
authors: van Aalst
authors: René C
authors: RC
authors: Schweizer
authors: Jan-Willem J
authors: JW
authors: Lammers
authors: Hubert G M
authors: HG
authors: Leufkens
authors: Jan A M
authors: JA
authors: Raaijmakers
authors: Madelon
authors: M
authors: Bracke
authors: Leo
authors: L
authors: Koenderman
mesh_terms: D000328:Adult; D000485:Allergens / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology; D001249:Asthma / Q000276:immunology*; D001435:Bacteriophages; D001769:Blood / Q000276:immunology; D002478:Cells, Cultured; D045142:Cross-Priming; D004804:Eosinophils / Q000276:immunology; D000939:Epitopes / Q000032:analysis / Q000276:immunology; D005260:Female; D006098:Granulocytes / Q000276:immunology*; D006801:Humans; D008297:Male; D009504:Neutrophils / Q000276:immunology; D010641:Phenotype; D017452:Receptors, IgG / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D012130:Respiratory Hypersensitivity / Q000276:immunology*
chemical_list: D000485:Allergens; D000911:Antibodies, Monoclonal; D000939:Epitopes; D017452:Receptors, IgG