Maize food allergy: lipid-transfer proteins, endochitinases, and alpha-zein precursor are relevant maize allergens in double-blind placebo-controlled maize-challenge-positive patients

Anal Bioanal Chem. 2009 Sep;395(1):93-102. doi: 10.1007/s00216-009-2945-z. Epub 2009 Aug 11.


Italian patients with maize anaphylaxis have been shown to have IgE toward two major maize allergens: an alpha-amylase inhibitor and a 9-kDa LTP. A complete study on maize food allergens in patients with positive maize double-blind, placebo-controlled food challenge (DBPCFC) is lacking. The objective was to utilize the three maize protein fractions to identify and characterize the most relevant IgE-binding proteins recognized by the sera of Italian and Swiss patients with either a positive maize-DBPCFC or a history of maize-induced anaphylaxis. Osborne's protein fractions of maize were extracted to obtain water-soluble, total zein, and total protein fractions. Protein IgE-binding capacity was investigated by SDS-PAGE immunoblotting using the sera from DBPCFC-positive patients and from patients with maize-induced anaphylaxis. Purified maize LTP was used to inhibit the IgE immunoblotting of the three protein fractions. IgE immunoblotting demonstrated that the 9-kDa LTP was recognized by all the Italian patients and by none of the Swiss patients. Other allergens were: 14-kDa alpha-amylase inhibitor, 30-kDa endochitinases A and -B, 19 kDa zein-beta precursor, and 26 kDa zein-alpha precursor; a newly described allergen, the globulin-2 precursor, identified in the total protein fraction. It is noteworthy that maize LTP and endochitinase were cross-reactive with grape LTP and one grape endochitinase. LTP was found to be the only major allergen in Italian patients with either positive maize challenge or a history of maize-induced anaphylaxis. We have identified other maize allergens in subjects with maize food allergy, as grape cross-reactive endochitinase, however, the clinical significance of these proteins needs to be investigated in larger groups of patients with allergy to these food items.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Anaphylaxis / etiology
  • Antigens, Plant
  • Carrier Proteins / immunology*
  • Child
  • Chitinases / immunology*
  • Double-Blind Method
  • Female
  • Food Hypersensitivity / etiology*
  • Food Hypersensitivity / immunology
  • Humans
  • Immunoglobulin E / metabolism
  • Italy
  • Male
  • Middle Aged
  • Placebos
  • Plant Proteins
  • Protein Binding
  • Serologic Tests / methods*
  • Young Adult
  • Zea mays / immunology*
  • Zein / immunology*


  • Antigens, Plant
  • Carrier Proteins
  • Placebos
  • Plant Proteins
  • lipid transfer protein
  • Immunoglobulin E
  • Zein
  • Chitinases