title: A 50 kDa maize gamma-zein has marked cross-reactivity with the almond major protein.
abstract: Cross-reactivity of antibodies against almond major protein (AMP, a legumin), the major almond allergen, with cereal proteins may cause problems in detecting almond contaminants in cereal products when antibody-based assays are used. Rabbit polyclonal IgG antiserum produced against AMP was used to test cross-reactivity with protein extracts from maize, a cereal commonly found in breakfast and snack foods. Gradient SDS-PAGE followed by Western blotting was performed, and two cross-reactive proteins were detected by chemiluminescence. A fraction of maize proteins purified by elution from an IgG anti-AMP affinity column followed by electrophoreseis and immunoblotting showed a high degree of cross-reactivity with a minor 50 kDa protein of maize, as well as low cross-reactivity with the 27 kDa gamma-zein. The 50 kDa cross-reactive protein was identified as the 50 kDa gamma-zein by immunoreaction with anti-50 kDa gamma-zein antiserum. Notably, the 50 kDa maize gamma-zein also reacted with IgE from pooled human sera from patients with self-reported severe almond allergies. The high immunoreactivity of the 50 kDa gamma-zein should be considered in maize quality improvement programs, and such notable cross-reactivity is of relevance in the design of antibody-based assays for almond allergen detection.
authors.affiliation: Department of Food Science, Purdue University, West Lafayette, Indiana 47907-2009, USA.
authors.forename: Sung-Ho
authors.initials: SH
authors.lastname: Lee
authors.forename: Mustapha
authors.initials: M
authors.lastname: Benmoussa
authors.forename: Shridhar K
authors.initials: SK
authors.lastname: Sathe
authors.forename: Kenneth H
authors.initials: KH
authors.lastname: Roux
authors.forename: Suzanne S
authors.initials: SS
authors.lastname: Teuber
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Hamaker
mesh_terms: D000485:Allergens / Q000737:chemistry / Q000276:immunology; D000595:Amino Acid Sequence; D000918:Antibody Specificity; D004591:Electrophoresis, Polyacrylamide Gel; D005512:Food Hypersensitivity / Q000276:immunology; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000276:immunology; D008163:Luminescent Measurements; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010940:Plant Proteins / Q000737:chemistry / Q000276:immunology*; D027861:Prunus / Q000737:chemistry*; D016415:Sequence Alignment; D003313:Zea mays / Q000737:chemistry*; D015028:Zein / Q000737:chemistry / Q000276:immunology*
chemical_list: D000485:Allergens; D010940:Plant Proteins; D007073:Immunoglobulin E; D015028:Zein