Fig. 2

Transient ablation of regulatory T cells strongly enhances the therapeutic effect of functionalized CaP nanoparticles. a DEREG mice on C57BL/6 background were vaccinated as described in Additional file 1: Figure S1. In addition, mice were injected with 800 ng/mouse of diphtheria toxin (DT) 2 and 4 days before vaccination as well as 2 and 4 days after vaccination with functionalized CaP nanoparticles. b Frequencies of Foxp3⁺ CD4⁺ regulatory T cells and c GzmB expression by CD8⁺ or CD4⁺ CD43⁺ T cells in the spleen of naïve and FV chronically infected DEREG mice after vaccination 7 d.p.v. Representative dot plots are shown. d Splenocytes were isolated 7 d.p.v. from chronically FV infected DEREG mice treated with or without DT and restimulated ex vivo with 5 µg/ml of GagL_85–93 or gp70_123–141 peptide. After 24 h, the numbers of IFN-γ-producing CD4⁺ and CD8⁺ T cells were determined by ELISpot. The figure illustrates the results of three independent experiments. 9 mice per group are shown. Bars represent mean ± SEM. One-way ANOVA followed by Bonferoni’s multiple comparison test was performed to analyze statistics of multiple group sets. *p < 0.05; **p < 0.01; ***p < 0.001