Core alpha 1 -> 3-fucose is a common modification of N-glycans in parasitic helminths and constitutes an important epitope for IgE from Haemonchus contortus infected sheep

Synthesis of parasite specific IgE plays a critical role in the defence aga inst helminth infections. We report here that IgE from serum from Schistoso ma mansoni infected mice and Haemonchus contortus infected sheep recognizes complex-type N-glycans from Arabidopsis thaliana, which contain R-GlcNAc b eta 1-->4(Fuc alpha 1 -->3)GlcNAc beta 1-Asn (core alpha 1-->3-Fuc) and Xyl beta 1-2Man beta 1 --> 4GlcNAc beta 1-R (core beta 1 --> 2-Xyl) modificati ons, and honeybee phospholipase A2, which carries N-glycans that contain th e core alpha 1-->3-Fuc epitope, Evidence is presented that core alpha 1-->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 co re alpha 1-->3-Fuc antigen may contribute to induction of a Th2 response le ading to the production of IgE, In addition we show here that IV-glycans ca rrying core alpha 1-->3-Fuc and beta 1-->2-Xyl antigens are synthesized by many parasitic helminths and also by the free living nematode Caenorhabditi s elegans. Since N-glycans containing the core alpha 1-->3-Fuc have also be en implicated in honeybee and plant induced allergies, this conserved glyca n might represent an important common IgE epitope, (C) 1999 Federation of E uropean Biochemical Societies.