Effect of Different Adjuvants on the Immunogenicity of a Recombinant Herpes Zoster Vaccine in Mice, Rats and Non-Human Primates

<b>Background</b>: Varicella zoster virus (VZV) is a globally circulating pathogen that usually infects children and establishes a latent state in host nerve cells. Recurrence of latent varicella zoster virus (VZV) is often triggered by predisposing factors such as aging and immune dysfunction, which may lead to herpes zoster (HZ) and its related complications. At present, there is no specific treatment for herpes zoster or postherpetic neuralgia, so vaccination is an important preventive measure. <b>Methods</b>: In this study, a variety of vaccine formulations were developed by combining the gE protein with different adjuvants. Enzyme-linked immunosorbent assay (ELISA), flow cytometry, and ELISpot were used to evaluate the immune response induced by each combination of vaccines in C57BL/6 mice, and the optimal combination of adjuvants. Then, its immunogenicity was verified in SD rats and rhesus monkeys. <b>Results</b>: All combinations of gE/squalene oil-in-water emulsion (SWE)/CpG1018 adjuvant induced a good humoral immune response 28 days after secondary immunization. GE/SWE/CPG1018, combined with adjuvant, induced a higher cellular immune response in mice. The selected gE/SWE/CpG1018 combined with the adjuvant vaccine combination could effectively stimulate the humoral and cellular immune responses in SD rats and rhesus monkeys. <b>Conclusions</b>: The gE/SWE/CpG1018 combined with adjuvant vaccine may be a low-cost and highly effective vaccine candidate for the prevention of varicella zoster.