CpG ss-ODN augments the immunogenicity of K25V fusion peptide.

(A) 25 μg of ss-ODN #1826 was mixed with fusion peptide K25V dissolved as described in the legend to Figure 1. A dose titration of peptide was set up, with a constant volume maintained by dilution with N-saline. A solution of 100 μL containing peptide and 25 μg ss-ODN was injected once subcutaneously into the following numbers of Tg mice: 100 nmol, n = 6; 50 nmol, n = 10; and 25 nmol, n = 2. After 14 days, mice were killed and spleens were removed, and one IVS was carried out as described in “Materials and methods.” CRA was performed as described in “Materials and methods” with pp65_495-503 cytotoxicity represented by filled symbols and p53_149-157 specificity represented by open symbols. Targets and calculation of cytotoxicity were the same as described in the legend to Figure 1. (B) 50 nmol of KTet₈₃₀V (Table 1) alone (●) or with 25 μg ss-ODN #1826 (⋄) was used to immunize Tg mice (n = 6) as described in panel A. (C) The same conditions as panel B (n = 4), except the fusion peptide is Tet₆₃₉V (Table 1), and symbols represent 50 nmol peptide alone (●) or with 25 μg ss-ODN #1826 (⋄).