Fig. 3.

First-step HPLC of oligosaccharide fractions of uninfected and N.b-infected rats using Tskgel Amide-80 columns and the reactivity of oligosaccharides with HCM31. Fractions UA1 (upper panel) and IA1 (lower panel) were loaded on the column and then eluted with a 30 min linear gradient of acetonitrile (68–55%) (a). Absorbance was monitored at 210 nm. The antigenic activities of various amounts of the oligosaccharides from purified oligosaccharide fractions, IA1-2 (○), IA1-3(•), IA1-5 (Δ) and IA1-8 (▴), in infected rats were examined by competitive ELISA (b), as described in Section 4. Data are expressed as mean ± SD from three experiments.