Immune response and protective efficacy of mannosylated polyethylenimine (PEI) as an antigen delivery vector, administered with a Streptococcus agalactiae DNA vaccine in Nile tilapia (Oreochromis niloticus)

Fish Shellfish Immunol. 2023 Apr:135:108684. doi: 10.1016/j.fsi.2023.108684. Epub 2023 Mar 13.

Abstract

This study examined the effectiveness of a DNA vaccine for S. agalactiae that was delivered by mannose-based polyethyleneimine (Man-PEI). The results showed that Man-PEI/pcDNA-Sip stimulated a higher serum antibody titer compared to control or other vaccine groups (p < 0.05). Additionally, it induced higher expression of immune-related genes, and increased activities of superoxide dismutase (SOD), acid phosphatase (ACP) and alkaline phosphatase (AKP). Furthermore, the Man-PEI/pcDNA-Sip group showed an improved relative percent survival (RPS) of 85.71%. These results demonstrate the potential value of Man-PEI as a vaccine delivery vehicle, and suggest that it can be effective in boosting the immune protective rate induced by pcDNA-Sip vaccines.

Keywords: Antibody titer; Antigen delivery vector; Gene expression analysis; Histopathological examination; Immune response; Man-PEI.

MeSH terms

  • Animals
  • Cichlids*
  • Fish Diseases* / prevention & control
  • Immunity
  • Polyethyleneimine / pharmacology
  • Streptococcal Infections* / prevention & control
  • Streptococcal Infections* / veterinary
  • Streptococcal Vaccines*
  • Streptococcus agalactiae
  • Vaccines, DNA*

Substances

  • Vaccines, DNA
  • mannose polyethylenimine
  • Polyethyleneimine
  • Streptococcal Vaccines