STRUCTURES AND CONTRIBUTION TO THE ANTIGENICITY OF OLIGOSACCHARIDES OF JAPANESE CEDAR (CRYPTOMERIA-JAPONICA) POLLEN ALLERGEN CRY-J-I - RELATIONSHIP BETWEEN THE STRUCTURES AND ANTIGENIC EPITOPES OF PLANT N-LINKED COMPLEX-TYPE GLYCANS

The oligosaccharide structures of Cry j I, a major allergenic glycopro tein of Cryptomeria japonica (Japanese cedar, sugi), were analysed by 400 MHz H-1-NMR and two-dimensional sugar mapping analyses. The four m ajor fractions comprised a series of biantennary complex type N-linked oligosaccharides that share a fucose/xylose-containing core and gluco samine branches including a novel structure with a nongalactosylated f ucosylglucosamine branch. Rabbit polyclonal anti-Cry j I IgG antibodie s cross-reacted with three different plant glycoproteins having the sa me or shorter N-linked oligosaccharides as Cry j I. ELISA and ELISA in hibition studies with intact glycoproteins, glycopeptides and peptides indicated that both anti-Cry j I IgGs and anti-Sophora japonica bark lectin II (B-SJA-II) IgGs included oligosaccharide-specific antibodies with different specificities, and that the epitopic structures agains t anti-Cry j I IgGs include a branch containing alpha 1-6 linked fucos e and a core containing fucose/xylose, while those against anti-B-SJA- II IgGs include nonreducing terminal mannose residues. The crossreacti vities of human allergic sera to miraculin and Clerodendron Trichotomu m lectin (CTA) were low and inhibition studies suggested that the olig osaccharides on Cry j I contribute little or only conformationally to the reactivity of specific IgE antibodies.