Figure 4. Treatment with neuraminidase enables PrP^C–Ig-LEC11 to bind all three selectins.

ELISA plates were precoated with identical amounts of E-selectin–Ig, L-selectin–Ig, P-selectin–Ig or NCAM–Ig fusion proteins. Equal amounts of affinity-purified, PBS-treated or neuraminidase-treated PrP^C–Ig LEC11 were added on to the plates. The bound fusion proteins were then detected with a biotinylated anti-PrP^C mAb, 8H4. Bound antibody was detected further with streptavidin–HRP. Results are the means±S.D. for four experiments (n=8 for each sample). Removal of sialic acid enables PrP^C–Ig-LEC11 to bind all three selectin–Ig fusion proteins. Neuraminidase-treated PrP^C–Ig-LEC11 remained unable to bind NCAM–Ig fusion protein. OD, absorbance.