Core α1→3‐fucose is a common modification of N‐glycans in parasitic helminths and constitutes an important epitope for IgE from Haemonchus contortus infected sheep

Abstract

Synthesis of parasite specific IgE plays a critical role in the defence against helminth infections. We report here that IgE from serum from Schistosoma mansoni infected mice and Haemonchus contortus infected sheep recognizes complex‐type N‐glycans from Arabidopsis thaliana, which contain R‐GlcNAcβ1→4(Fucα1→3)GlcNAcβ1‐Asn (core α1→3‐Fuc) and Xylβ1→2Manβ1→4GlcNAcβ1‐R (core β1→2‐Xyl) modifications, and honeybee phospholipase A2, which carries N‐glycans that contain the core α1→3‐Fuc epitope. Evidence is presented that core α1→3‐fucosylated N‐glycans bind a substantial part of the parasite specific IgE in serum of H. contortus infected sheep. These results suggest that the core α1→3‐Fuc antigen may contribute to induction of a Th2 response leading to the production of IgE. In addition we show here that N‐glycans carrying core α1→3‐Fuc and β1→2‐Xyl antigens are synthesized by many parasitic helminths and also by the free living nematode Caenorhabditis elegans. Since N‐glycans containing the core α1→3‐Fuc have also been implicated in honeybee and plant induced allergies, this conserved glycan might represent an important common IgE epitope.