Fig. 4.

Freeze-drying formulations #4 and #5 protect the immunogenicity of adenovirus vaccine from being damaged due to lyophilization. A Vaccination schedule in C57BL/6 mice. Three different groups were designed using the same two inoculations of the DNA vaccine and different treatments of recombinant adenovirus vaccine. Each DNA vaccine (pSV1.0-ENV 100 ng per mouse) and adenovirus vaccine (Ad5-ENV 10⁸ TCID50 per mouse) were administered into mice via intramuscular injection at 2-week intervals. Two weeks after the last vaccination, we detected the immunogenicity of the viral vaccines. B–C The protection of antigen-specific T cell responses was detected by ELISPOT (B) and intracellular cytokine staining (C). Mouse splenocytes were stimulated by the ENV peptide pool. D The protection of specific binding antibodies was measured by ELISA at the same time. Data are the mean of each cohort (N = 6), and error bars indicate SD (***P < 0.001, *P < 0.05).