Fig. 6

Amyloid-β peptide 1–42 (Aβ42) epitope binding of immunoglobulin G (IgG), IgA, and IgM isotypes at different time points of the immunization schedule. A panel of shorter Aβ peptides (Aβ_1–16, Aβ_6–20, Aβ_10–26, Aβ_17–31, Aβ_22–35, and Aβ_23–42) was used to detect linear epitope binding of antibodies generated in the animals after DNA Aβ42 immunization. a Aβ epitope binding pattern of IgG, IgA, and IgM antibodies observed after three immunizations. b Epitope binding pattern after four immunizations. c Epitope binding pattern found with six immunization time points. d Aβ epitope binding of antibodies of the IgG, IgA, and IgM isotypes after the 3-month rest period. Results are presented in box-and-whisker graphs with minimum to maximum values. Median levels are indicated by the horizontal lines, and the SEM is shown for all columns above and below the boxes. Each circle within the bars represents the value for one individual monkey that had received active DNA Aβ42 immunizations. IgG antibodies are indicated in blue, IgA antibodies are indicated in red, and IgM antibodies are indicated in green. OD ₄₅₀ 450-nm Optical density