title: Rice allergy demonstrated by double-blind placebo-controlled food challenge in peach-allergic patients is related to lipid transfer protein reactivity.
abstract: BACKGROUND
  The risk factors for sensitisation to rice and the involved allergens are still partially unknown. In this study we evaluated the clinically relevant aspects of rice allergy in DBPCF-positive patients, the major rice allergens, the severity of peach- and rice-induced symptoms in respect to Pru p 3 sensitisation and the role of anti-rPru p 3 IgE levels as a risk factor for rice allergy.
  
  
  METHODS
  In 148 peach-allergic subjects, patients with allergic reactions to rice and rice-positive serum IgE were selected. Symptoms were verified by double-blind placebo-controlled food challenges (DBPCFCs), performed at a maximum dosage of 25 g. Rice allergens, identified by IgE immunoblotting, were characterised by N-terminal amino acid sequencing. The relationship between anti-rPru p 3, 1 and 4 IgE levels and rice symptoms were statistically analysed.
  
  
  RESULTS
  Eight out of 10 recruited rice-allergic patients had positive DBPCFCs, while 2 patients were not challenged due to their previously documented severe reactions. All patients with rice-induced symptoms were Pru p 3 positive and presented with higher anti-rPru p 3 levels than the rice-sensitised but tolerant patients. A 9-kDa lipid transfer protein, which was highly homologous to Pru p 3, was identified as the major rice allergen and elicited a positive response in all of the patients. Five patients reacted to a putative 15- to 17-kDa rice allergenic protein, and 3 patients reacted to an [alpha]-amylase/subtilisin inhibitor that was approximately 20 kDa.
  
  
  CONCLUSIONS
  Rarely, allergic reactions to rice can arise in patients with peach allergies who are sensitised to Pru p 3, particularly in patients with high anti-rPru p 3 IgE levels.
authors.affiliation: Allergology and Immunology Unit, Niguarda Ca' Granda Hospital, Milan, Italy. Elide.Pastorello @ ospedaleniguarda.it
authors.forename: Elide Anna
authors.initials: EA
authors.lastname: Pastorello
authors.forename: Joseph
authors.initials: J
authors.lastname: Scibilia
authors.forename: Laura
authors.initials: L
authors.lastname: Farioli
authors.forename: Laura
authors.initials: L
authors.lastname: Primavesi
authors.forename: Maria Gabriella
authors.initials: MG
authors.lastname: Giuffrida
authors.forename: Ambra
authors.initials: A
authors.lastname: Mascheri
authors.forename: Marta
authors.initials: M
authors.lastname: Piantanida
authors.forename: Corrado
authors.initials: C
authors.lastname: Mirone
authors.forename: Chrysi
authors.initials: C
authors.lastname: Stafylaraki
authors.forename: Marta Riva
authors.initials: MR
authors.lastname: Violetta
authors.forename: Michele
authors.initials: M
authors.lastname: Nichelatti
authors.forename: Donatella
authors.initials: D
authors.lastname: Preziosi
authors.forename: Laura
authors.initials: L
authors.lastname: Losappio
authors.forename: Valerio
authors.initials: V
authors.lastname: Pravettoni
mesh_terms: D000328:Adult; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D002851:Chromatography, High Pressure Liquid; D004311:Double-Blind Method; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005512:Food Hypersensitivity / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D008875:Middle Aged; D012275:Oryza / Q000276:immunology*; D028321:Plant Preparations / Q000276:immunology*; D010940:Plant Proteins / Q000276:immunology; D027861:Prunus / Q000276:immunology*; D011795:Surveys and Questionnaires
chemical_list: D002352:Carrier Proteins; D028321:Plant Preparations; D010940:Plant Proteins; C030363:lipid transfer protein; D007073:Immunoglobulin E