Figure 4
Immunologic profiles and in vivo tumor preventive effects of noncarrier naked CRT/E7 DNA vaccine dissolved in various media and bombarded at various pressures. (a) Representative figures of flow cytometry analysis of E7-specific CD8+ T-cell precursors. (b) Frequencies of E7-specific CD8+ T-cell precursors of noncarrier naked CRT/E7 DNA vaccine in various solutions (note: the numbers of E7-specific CD8+ T-cell precursors for noncarrier naked CRT/E7 DNA vaccinated mice in distilled H2O (ddH2O) or Tris-EDTA (TE) solution were higher than those in phosphate-buffered saline (PBS) solution (P<0.05, one-way analysis of variance (ANOVA)). (c) Titers of anti-E7 antibodies in mice vaccinated with noncarrier naked CRT/E7 DNA in various media (note: the titers of anti-E7 antibodies were not significantly different between the noncarrier naked CRT/E7 DNA groups, regardless of which solution used (P>0.05, one-way ANOVA). (d) In vivo tumor preventive experiments in mice vaccinated with noncarrier naked CRT/E7 DNA vaccine in various solutions (note: mice vaccinated with noncarrier naked CRT/E7 DNA vaccine in ddH2O or TE were 100% tumor-free after 60 days of TC-1 challenge). However, only 60% of mice vaccinated with noncarrier naked CT/E7 DNA vaccine in PBS were tumor-free after 60 days of TC-1 challenge. (e) In vivo tumor preventive experiments in mice that received noncarrier naked CRT/E7 DNA at various pressures (note: mice vaccinated at 50 or 60 psi were 100% tumor-free after 60 days of TC-1 challenge). However, only 40 and 60% of mice were tumor-free after being vaccinated at 30 and 40 psi, respectively.
