title: Elevated secretion of myeloperoxidase by neutrophils from asthmatic patients: the effect of immunotherapy.
abstract: BACKGROUND
  There is increasing evidence of neutrophil participation in asthma and the allergic process. After activation, neutrophils release myeloperoxidase (MPO) together with other granule enzymes.
  
  
  OBJECTIVE
  In this study we attempted to evaluate the release of MPO in vitro by neutrophils from asthmatic patients and the relationship between neutrophil degranulation and lung function, measured as FEV(1), of the patients. We also investigated the possible role of immunotherapy in the release of MPO by neutrophils.
  
  
  METHODS
  Neutrophils were stimulated with formyl-methionyl-leucyl-phenylalanine for 45 minutes at 37 degrees C. MPO released from neutrophils was assayed by using an MPO enzyme immunoassay.
  
  
  RESULTS
  Neutrophils released statistically significantly higher MPO levels in the asthmatic patients not receiving immunotherapy than in the healthy group. A significant inverse correlation was observed in the asthmatic group not receiving immunotherapy between MPO secretion and lung function, measured as FEV(1), of the patients. Neutrophils of the asthmatic group receiving immunotherapy released significantly less MPO than did those of the asthmatic group not receiving immunotherapy, with MPO levels equal to those from nonallergic subjects.
  
  
  CONCLUSIONS
  We conclude that neutrophils obtained from allergic asthmatic patients have an increased propensity to release MPO. The experiments described here provide evidence that there is a significant inverse relationship between levels of MPO released by neutrophils from allergic patients and lung function, as assessed by FEV(1). Our study suggests that immunotherapy actively modifies the release of MPO in vitro by neutrophils from allergic asthmatic patients.
authors: Departamento de Medicina, Servicio Regional de Inmunología y Alergia, Hospital Universitario Virgen Macarena, Universidad de Sevilla, Seville, Spain.
authors: J
authors: J
authors: Monteseirín
authors: I
authors: I
authors: Bonilla
authors: J
authors: J
authors: Camacho
authors: J
authors: J
authors: Conde
authors: F
authors: F
authors: Sobrino
mesh_terms: D000328:Adult; D001249:Asthma / Q000276:immunology* / Q000628:therapy; D015550:Cell Degranulation; D004305:Dose-Response Relationship, Drug; D005541:Forced Expiratory Volume; D006801:Humans; D007167:Immunotherapy; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects / Q000201:enzymology*; D009195:Peroxidase / Q000378:metabolism*
chemical_list: D009240:N-Formylmethionine Leucyl-Phenylalanine; D009195:Peroxidase