Fig. 7
Specificity of antibodies in plasma of DNA amyloid-β peptide 1–42 (Aβ42) immunized rabbits to Aβ1–42. Plasma samples from the sixth immunization time point of the six immunized rhesus monkeys were tested for binding to a variety of different peptides (Aβ1–42, scrambled Aβ1–42, islet amyloid protein [IAPP], serum amyloid P component [SAP], prion protein fragments [Prp], tau peptide repeat 2 domain, tetanus toxin peptide [TTX], ovalbumin peptides [OVA]). Plasma was diluted 1:500 for these assays. In the comparison of binding to Aβ1–42, significant differences were found for binding of immunoglobulin G (IgG; blue bars) and IgA (red bars) antibodies in plasma to the distinct peptides tested (indicated by *, **, *** p values above the bars). Differences in IgG and IgA antibody binding in plasma samples from the immunized monkeys to nonrelated OVA peptides compared with binding to Aβ1–42 were nonsignificant (Mann-Whitney p values of 0.1246 and 0.5532, respectively). OD 450 450-nm Optical density