Identification of unique peanut and soy allergens in sera adsorbed with cross-reacting antibodies.

Published

Journal Article

BACKGROUND:Soybean and peanut are members of the legume family and share several common antigenic fractions. Patients allergic to one of these foods have serum IgE antibodies that immunologically cross-react with other legumes. Nevertheless, ingestion of other legumes generally does not induce an allergic reaction, suggesting that cross-reacting antibodies are not clinically relevant. OBJECTIVE:This study was designed to identify unique peanut or soybean antigenic fractions, with sera adsorbed to remove cross-reacting antibodies, thus resulting in sera with IgE antibodies unique to either soy or peanut. METHODS:Cross-reacting antibodies to soy were removed from the sera of two patients allergic to peanut and soy and three patients allergic to peanut by soy-affinity chromatography. Cross-reacting antibodies to peanut were adsorbed from the sera of a patient allergic to peanut and soy and a patient allergic to peanut by peanut-affinity chromatography. Adequate removal of cross-reacting antibodies was verified by ELISA after each adsorption step. Unadsorbed sera and sera adsorbed to remove cross-reacting antibodies (either to soy or to peanut) were assayed for specific IgE binding to peanut or soy immunoblots. RESULTS:Unique peanut-specific IgE antibodies (i.e., soy antibody-adsorbed) were found to bind to peanut fractions at 46, 29, 25, 19, 17, 14, and 5 kd on immunoblots of whole peanut protein. Similarly, unique soy-specific IgE (i.e., peanut antibody-adsorbed) were found to bind a fraction at 46 kd, and to a lesser extent, to a fraction at 21 kd on immunoblots of whole soy protein. The 73% reduction of IgE antibody binding to peanut by ELISA after adsorption of cross-reacting antibodies indicates extensive cross-reactivity between soy and peanut antigens. CONCLUSIONS:Antigen-affinity chromatography is an effective method for removal of cross-reacting antibodies. We identified IgE antibody binding (with sera where cross-reacting antibodies were removed) to several unique antigenic fractions of peanut and soy. Further studies will determine the clinical significance of these fractions in IgE-mediated food hypersensitivity reactions.

Full Text

Cited Authors

  • Eigenmann, PA; Burks, AW; Bannon, GA; Sampson, HA

Published Date

  • November 1996

Published In

Volume / Issue

  • 98 / 5 Pt 1

Start / End Page

  • 969 - 978

PubMed ID

  • 8939161

Pubmed Central ID

  • 8939161

Electronic International Standard Serial Number (EISSN)

  • 1097-6825

International Standard Serial Number (ISSN)

  • 0091-6749

Digital Object Identifier (DOI)

  • 10.1016/s0091-6749(96)80014-5

Language

  • eng