Adjuvant effects of combination monophosphoryl lipid A and poly I:C on antigen-specific immune responses and protective efficacy of influenza vaccines

Sci Rep. 2023 Jul 28;13(1):12231. doi: 10.1038/s41598-023-39210-6.

Abstract

Toll-like receptor (TLR) agonists improve vaccine immunogenicity and efficacy, but they are currently unlicensed as adjuvants in influenza vaccines. This study aimed to investigate whether a combination of monophosphoryl lipid A (MPL, a TLR4 agonist) and polyriboinosinic polyribocytidylic acid (poly I:C, a TLR3 agonist) can enhance the protective efficacy of an inactivated A/Puerto Rico/8/1934 (A/PR8) H1N1 influenza vaccine against homologous influenza infection and minimize illness outcomes. Results showed that combination MPL and poly I:C adjuvanted influenza vaccination increased the production of antigen-specific antibodies, decreased the levels of cytokines and cellular infiltrates at the infection sites, and induced significant memory T and B cell responses in mice. The results of this study suggest that the combination of MPL and poly I:C can be developed into a possible adjuvant for enhancing the efficacy of influenza vaccines.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic / pharmacology
  • Adjuvants, Pharmaceutic
  • Animals
  • Antibodies, Viral
  • Humans
  • Immunity
  • Influenza A Virus, H1N1 Subtype*
  • Influenza Vaccines*
  • Influenza, Human*
  • Mice
  • Mice, Inbred BALB C
  • Poly I-C / pharmacology

Substances

  • Influenza Vaccines
  • Poly I-C
  • monophosphoryl lipid A
  • Antibodies, Viral
  • Adjuvants, Immunologic
  • Adjuvants, Pharmaceutic