Depletion of CD25+CD4+T cells (Tregs) enhances the HBV-specific CD8+ T cell response primed by DNA immunization

Figure 2 Flow cytometry analysis to detect HBV-specific CD8⁺ T cells. Mice (six mice per group) were immunized by HBV plasmid DNA with or without anti-CD25 mAb treatment to eliminate CD25⁺ cells. PBMCs were harvested and the presence of HBV-specific CD8⁺ T cells were examined by flow cytometry on the 10 and 30 d after DNA immunization. A: HBV-specific CD8⁺ T cells were detected by S28-39 peptide loaded DimerX staining. Peptide unloaded empty DimerX was used as a control. B: Intracellular IFN-γ staining was performed to detect functional HBV S23-39 specific CD8⁺ T cells. PBMCs were incubated with 1 μg/mL of S28-39 peptide for 6 h and stained for the production of IFN-γ. Three experiments were performed with similar results. Representative responses of PBMCs from one mouse are shown in each panel.