Figure 7

Dissociation of Aβ-IgG immune complexes occurs at both pH 2.5 and pH 3.5. Mouse anti-human Aβ1–16 monoclonal antibody (6E10) at 10 μg/ml (7A) and serum from mice vaccinated with Aβ diluted 1:100 were preincubated with Aβ1–42 peptide at 1 μg/ml to form antigen-antibody complexes (solid bars) or preincubated with PBS as a control (open bars) at 37°C for 60 minutes. Aliquots from each sample were then incubated with a 10-fold larger volume (1:1000 final serum dilution in panel B) of dissociation buffer at pH 7, pH 2.5 and pH 3.5, respectively, for 20 minutes, separated by centrifugation through 10,000 MW filters, neutralized and reconstituted to original volume for standard ELISA assay with full length human Aβ coating the plate.