Fig. 6
Analysis of Aβ-specific immune responses in APPPS1 mice upon vaccination with Aβ-derived nonamer epitopes. APPPS1 mice or WT littermates were immunized with indicated native or NP-modified peptides mixed in CpG/HBV/IFA or with PBS/CpG/HBV/IFA alone. (a) Frequency of peptide-specific IFNγ-producing cells among CD8+ lymphocytes in the blood was determined 14 days after vaccination, by intracellular IFNγ staining after restimulation with the native or NP peptides. (b) Frequency of Aβ-specific IFNγ-secreting splenocytes in immunized mice, as assessed by ELISPOT. Fourteen days after vaccination, spleen cells (106/wells) were restimulated in triplicate for 18 h with either the matching native or NP peptide or with HBV-derived helper peptide (10 μg/ml). In the case of immunization with PBS/CpG/HBV/IFA, splenocytes were restimulated with each of the native or NP peptides and data are expressed as the mean of the two values obtained for each category of peptide (i.e., native or NP). Splenocytes from immunized mice were also stimulated in vitro with mitomycin-treated 1C11 cells (2 × 104/wells). Results are presented as numbers of IFN-γ-secreting cells per 106 splenocytes, calculated after subtracting the mean number of spots obtained in the absence of peptide or cells. Mean ± SD (three to four mice/group). Results are representative of two independent experiments. Mann–Whitney U test, *p ≤ 0.05