Fig. 1
Comparison of HPV16 E7-specific CD8+ T cell responses induced by different combination of pNGVL4a-Sig/E7(detox)/HSP70 DNA vaccine and TA-CIN vaccination. Five to eight weeks old female C57BL/6 mice (5 mice/group) were vaccinated with 1) 25 μg/mouse of pNGVL4a-Sig/E7(detox)/HSP70 DNA in 50 μl via intramuscular injection (leg muscle) three times with 1-week intervals between each vaccination (D + D + D); 2) 25 μg/mouse of TA-CIN in 20 μl via i.d. injection (lower back) three times with 1-week intervals between each vaccination (P + P + P); 3) 25 μg/mouse of pNGVL4a-Sig/E7(detox)/HSP70 DNA in 50 μl via intramuscular injection twice followed by once with 25 μg/mouse of TA-CIN in 20 μl via i.d. injection with 1-week intervals between each vaccination (D + D + P); 4) 25 μg/mouse of pNGVL4a-Sig/E7(detox)/HSP70 DNA in 50 μl via intramuscular injection once followed by twice with 25 μg/mouse of TA-CIN in 20 μl via i.d. injection with 1-week intervals between each vaccination (D + P + P); 5) 25 μg/mouse of pNGVL4a-Sig/E7(detox)/HSP70 DNA in 50 μl via intramuscular injection once, followed by 25 μg/mouse of pNGVL4a-Sig/E7(detox)/HSP70 DNA in 50 μl via intramuscular injection +25 μg/mouse of TA-CIN in 20 μl via i.d. injection concomitantly once, followed by 25 μg/mouse of TA-CIN in 20 μl via i.d. injection one time, with 1-week intervals between each set of vaccinations (D + DP + P); and 6) 25 μg/mouse of pNGVL4a-Sig/E7(detox)/HSP70 DNA in 50 μl via intramuscular injection +25 μg/mouse of TA-CIN in 20 μl via i.d. injection concomitantly three times with 1-week interval between each set of vaccinations (DP + DP + DP). Seven days after last vaccination, PBMCs were prepared and stained with anti-mouse CD8 and HPV16 E7 tetramer. Splenocytes were prepared and stimulated with 1 μg/ml of HPV16 E7aa49–57 peptide at the presence of GolgiPlug (1 μl/ml) overnight at 37 °C and stained with anti-mouse CD8 followed by intracellular IFN-γ. The data were acquired with FACSCalibur and analyzed with CellQuest. a Schematic illustration of the experiment. b and c Flow cytometry analysis of HPV16 E7-specific CD8+ T cells in peripheral blood. d and e Flow cytometry analysis of HPV16 E7-specific CD8+ T cells in spleen