title: Basophil response and the induction of a tolerance in venom immunotherapy: a long-term sting challenge study.
abstract: BACKGROUND
  There is no in vitro test to predict the induction of long-term tolerance in patients treated with venom immunotherapy (VIT). The aim of this study was to investigate whether immunotherapy-induced changes in basophil responsiveness reflect a state of protection and the induction of a tolerance.
  
  
  METHODS
  Twenty-three patients with allergic reaction after Hymenoptera sting (11 wasp and 12 honeybee) were treated with VIT. In all patients, a CD63 basophil activation test was performed before the beginning of immunotherapy, after 1 year and after completing 4-6.5 years of immunotherapy (approximately 1 year after stopping). The tolerance was then evaluated by a sting challenge test. The basophil activation test was repeated 3-6 months after the challenge.
  
  
  RESULTS
  Twenty-two subjects showed a negative sting challenge, and one subject, a positive sting challenge. Allergen-specific basophil response remained unchanged after 1 year of immunotherapy. However, after immunotherapy, a significant and approximately fourfold decrease was demonstrated in all tolerant subjects mainly in response to submaximal 0.1 μg/ml allergen concentration. This depression was sustained and did not change with the sting challenge test. In a nontolerant patient with a positive sting challenge, basophil response did not change.
  
  
  CONCLUSIONS
  Our results suggest that the depression of allergen-specific basophil response seems to be associated with the induction of a tolerance after completing a course of VIT.
authors.affiliation: University Clinic of Respiratory and Allergic Diseases, Golnik, Slovenia.
authors.forename: R
authors.initials: R
authors.lastname: Eržen
authors.forename: M
authors.initials: M
authors.lastname: Košnik
authors.forename: M
authors.initials: M
authors.lastname: Silar
authors.forename: P
authors.initials: P
authors.lastname: Korošec
mesh_terms: D000328:Adult; D000368:Aged; D001180:Arthropod Venoms / Q000276:immunology*; D015549:Basophil Degranulation Test; D001491:Basophils / Q000276:immunology* / Q000378:metabolism; D003888:Desensitization, Immunologic; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology / Q000517:prevention & control*; D007108:Immune Tolerance / Q000276:immunology*; D007299:Insect Bites and Stings / Q000276:immunology*; D008297:Male; D008875:Middle Aged
chemical_list: D001180:Arthropod Venoms