SELECTED ARTICLES FROM THE RECENT LITERATURE 2004
12/21/04
What makes a food protein an allergen?
Summary
Background - Food allergies (FA) are found in about 8% of children and in 2-3% of adults. However, the majority of documented FA cases involve reactions to a limited number of foods. What characterizes the food proteins that are allergenic?
Findings - This subject was reviewed by Bannon of the Monsanto Co. in St. Louis, MO. A major attribute of an allergenic food protein is the capacity to elicit an IgE-mediated immune response. Also, very important is the capacity for IgE responses despite effect of food processing, and then effects of gastric acidity and digestive enzymes after the food is ingested. The number of linear epitopes which bind IgE antibody molecules is another determinant of allergenicity of particular food proteins.
Reference
Curr Allergy Asthma Rep 2004; 4:43-6
Editor's Comments
This review written from the standpoint of a food chemist provides interesting and valuable information. Recent studies in FA due to cow's milk and egg have shown that both 1) linear epitopes and 2) epitopes dependent on the tertiary structure of the molecule can present on the tertiary structure of the molecule in these 2 foods. The linear epitopes tend to be resistant to the catabolic effects of G-I acidity and enzymatic action. Children who make IgE antibodies to linear epitopes tend to retain their FA into adolescence and even adulthood. In comparison, FA in young children due mainly to IgE antibody responses to tertiary epitopes tends to spontaneously later in childhood.
|