Recent research published in the Zoonoses journal highlights the need to enhance vaccine efficacy against varicella zoster virus (VZV) infections, which are on the rise. The current in vivo utilization of antigens and adjuvants has been inefficient, limiting immune protection provided by VZV vaccines. Therefore, improving the efficiency of antigen and adjuvant utilization is crucial for boosting VZV vaccine performance.

To address this challenge, researchers developed a co-delivery system using manganese-coordinated lipid nanoparticles (Mn-LNPs). By coordinating palmitic acid with manganese through hydrothermal synthesis and incorporating it into lipid nanoparticles along with VZV glycoprotein E (gE) antigen and CpG adjuvant, the Mn-LNPs were able to enhance VZV vaccine-induced immune responses in a mouse model.

The Mn-LNPs were found to be positively charged spherical particles with a diameter of approximately 270 nm, encapsulating the VZV gE antigen and CpG adjuvant in a specific mass ratio. Compared to traditional aluminium adjuvants, the Mn-LNP co-delivery system significantly boosted VZV gE antigen-specific CD4+ and CD8+ T cell responses, resulting in increased levels of IFN-γ, TNF-α, and IL-2. Additionally, the Mn-LNPs outperformed commercial aluminium adjuvants in enhancing the antigen-specific IgG2b subclass response.

Overall, the Mn-LNP co-delivery system efficiently delivered VZV antigen and CpG adjuvant, leading to a substantial improvement in VZV vaccine-induced T cell responses. This innovative approach shows great promise in enhancing the efficacy of VZV vaccines and combating the increasing prevalence of VZV infections.