title: Utility of Basophil Activation Test for monitoring the acquisition of clinical tolerance after oral desensitization to cow's milk: Pilot study.
abstract: OBJECTIVE
  The quantification of basophil activation by flow cytometry is a useful tool for the assessment of immediate-type responses to food allergens and the prediction of clinical tolerance in food allergy patients. The aim of this study is to investigate how the analysis of allergen-induced CD63 up-regulation by flow cytometry can be effective in monitoring the acquisition of clinical tolerance by specific oral desensitization in food allergy. To our knowledge, this is the first study to examine this topic.
  
  
  METHODS
  Three male patients affected by cow's milk allergy underwent successful oral desensitization to cow's milk. In order to monitor the acquired clinical tolerance that occurred after treatment, we performed laboratory tests for total and specific IgE, specific IgG4 and the Basophil Activation Test (BAT) both at baseline and at the end of the desensitization protocol.
  
  
  RESULTS
  Using a fluorescent enzyme immunoassay, the comparison of specific cow's milk antibodies before and after treatment showed a decrease of specific IgE levels, without reaching normal values, and an increase of specific IgG4 levels. A complete suppression of cow's milk proteins (α-lactoalbumin, β-lactoglobulin and casein) induced CD63 regulation was observed in all three reported cases.
  
  
  CONCLUSIONS
  Using flow cytometry, food allergen-specific basophil responses could be monitored in order to identify an acquired tolerance induced by desensitization treatment. Although further studies are needed to develop this important new topic, it was interesting to note that the BAT seemed to be more sensitive and characterized by a close correlation with clinical tolerance.
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Nucera
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Pecora
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Buonomo
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Rizzi
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Arianna
authors.initials: A
authors.lastname: Aruanno
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Lucilla
authors.initials: L
authors.lastname: Pascolini
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Anna G
authors.initials: AG
authors.lastname: Ricci
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Di Rienzo
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Mezzacappa
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Ferraironi
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Giampiero
authors.initials: G
authors.lastname: Patriarca
authors.affiliation: Internal Medicine Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Gasbarrini
authors.affiliation: Allergy Department, Università Cattolica del Sacro Cuore, Policlinico A Gemelli, Rome, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Schiavino
keywords: Basophil Activation Test; CD63; IgE antibodies; cow's milk; cow's milk allergy; flow cytometry; immunoassays; milk proteins; oral desensitization; oral tolerance