HPLC analysis of the recHCG glycan pool. The HCG glycan pool was subjected to exoglycosidase digestions in order to assign structures (A). UND represents the undigested pool of glycans, where the arrows denote the peaks referred to in Tables 1 and 2. This pool was digested with combinations of sialidase A (ABS), β-galactosidase (BTG), α-fucosidase (BKF), hexosaminidase (GUH) and mannosidase (JBM). The composition of each large peak is described alongside. The structural abbreviations for glycans are as follows; all complex structures were assumed to have 2 core GlcNAc and 3 mannose residues, F represents the number of core linked fucose residues, Man(x) the number (x) of mannose residues on core GlcNAcs, A(x), the number (x) of antennae (GlcNAc) on a trimannosyl core, G(x), the number (x) of galactose residues β-linked to the antennae, S(x) the number (x) of sialic acids on antennae. For example, NeuAc2Gal2GlcNAc2Man3 + Fuc would be represented as FA2G2S2. A GU (glucose unit) scale is shown for clarity.