Figure 6

Incubation of sera at pH 3.5 does not induce artifactual ELISA signals nor inactivate authentic anti-Aβ antibody binding in ELISA assay. Sera collected from unvaccinated mice (6A) and mice vaccinated with Aβ 1–42 peptide (6B) were incubated with dissociation buffer at pH 7.0 (open bars), 3.5 (grid bars) or 2.5 (solid bars) for 20 minutes, separated by centrifugation through 10,000 MW filters neutralized and reconstituted to original volume. They were then incubated in a standard ELISA assay using full length Aβ to coat the plate. * P < 0.05 compared to pH 7.0; ** P < 0.001 compared to pH 7.0.