Recombinant Proteins and Peptides as Tools for Studying IgE Reactivity with Low-Molecular-Weight Glutenin Subunits in Some Wheat Allergies

摘要

Two genes of wheat low-molecular-weight glutenin subunits (LMW-GS),B16 and P73,were cloned and expressed in E.coll They were homologous to proteins encoded respectively at Glu-B3 and Glu-D3 loci.The N-terminal and C-terminal halves of B16 (NB16 and B16C) and the two chimeras combining the halves of the two genes (B16-P73 and P73-B16) were also expressed.All these constructs were compared for their reactivity with IgE from 24 patients suffering from different forms of wheat allergies.The results confirmed that LMW-GSs bound IgE in all adult allergies tested.Strong differences in reactivity between all the constructs were observed.They were disease-dependent.In wheat-dependent exercise-induced anaphylaxis (WDEIA),the reactivity of the constructs depended partly on common epitopes with omega-5 gliadins but also on differences in molecule conformation.The presence of NB16 in the constructs greatly influenced their IgE reactivity.