HAEMONCHUS-CONTORTUS GLYCOPROTEINS CONTAIN N-LINKED OLIGOSACCHARIDES WITH NOVEL HIGHLY FUCOSYLATED CORE STRUCTURES

Structural studies on the N-linked oligosaccharides of Haemonchus cont ortus, an economically important nematode that parasitizes domestic ru minants, have revealed core fucosylation of a type not previously obse rved in any eukaryotic glycoprotein. Mass spectrometric analyses were performed on detergent extracts of homogenized adult H. contortus and on purified H11, a glycoprotein isolated from intestinal brush borders which has been previously shown to be an effective vaccine antigen. T he major N-linked glycans identified in the present study have up to t hree fucose residues attached to their chitobiose cores. The fucoses a re found at the 3- and/or 6-positions of the proximal GlcNAc and at th e 3-position of the distal GlcNAc. The latter substitution is unique i n N-glycans. Most anti-H11 monoclonal antibodies are known to recogniz e carbohydrate epitopes, and it is possible that the newly discovered multifucosylated core structures are highly immunogenic in this glycop rotein.