FIG. 6.

Ad5 vectors with capsid-displaying retro-DAF complement inhibitor induce significantly diminished Ad-derived transgene-specific T-cell responses in Ad5-immune mice. WT BALB/c mice were made Ad5-immune by two 2-week-spaced IM injections with Ad5-Null (10¹⁰ vp/mouse), followed by one or two doses of either Ad5-Gag or Ad5-Gag-IX-dDAF (10¹⁰ vp/mouse, IM). At 14 dpi (one dose; left) or 28 dpi (two doses; right), splenocytes and PBMCs were harvested and processed as described in Materials and Methods. PBMCs (A) or splenocytes (B) derived from individual mice were analyzed for the presence of CD3⁺CD8⁺Gag-tetramer⁺ T cells by flow cytometry. Columns represent means ± SD. Statistical analysis was completed using one-way ANOVA with a Student-Newman-Keuls post hoc test; p < 0.05 was deemed a statistically significant difference. *p < 0.05, statistically different from naive mice; ^#p < 0.05, ^##p < 0.01, statistically different from WT Ad5-Gag mice. (C) Representative samples of Gag-tetramer staining of splenocytes, derived from each of three groups (28 dpi). (D) For intracellular cytokine staining, splenocytes (n = 5) collected at 14 dpi were stimulated with AMQMLKETI Gag-specific peptide and stained as detailed in Materials and Methods. Columns represent means ± SD. Statistical analysis was completed using one-way ANOVA with a Student-Newman-Keuls post hoc test; p < 0.05 was deemed a statistically significant difference. *p < 0.05, statistically different from naive mice; ^#p < 0.05, statistically different from WT Ad5-Gag mice.