Intranasal vaccination with influenza HA/GO-PEI nanoparticles provides immune protection against homo- and heterologous strains

Proc Natl Acad Sci U S A. 2021 May 11;118(19):e2024998118. doi: 10.1073/pnas.2024998118.


Intranasal (i.n.) immunization is a promising vaccination route for infectious respiratory diseases such as influenza. Recombinant protein vaccines can overcome the safety concerns and long production phase of virus-based influenza vaccines. However, soluble protein vaccines are poorly immunogenic if administered by an i.n. route. Here, we report that polyethyleneimine-functionalized graphene oxide nanoparticles (GP nanoparticles) showed high antigen-loading capacities and superior immunoenhancing properties. Via a facile electrostatic adsorption approach, influenza hemagglutinin (HA) was incorporated into GP nanoparticles and maintained structural integrity and antigenicity. The resulting GP nanoparticles enhanced antigen internalization and promoted inflammatory cytokine production and JAWS II dendritic cell maturation. Compared with soluble HA, GP nanoparticle formulations induced significantly enhanced and cross-reactive immune responses at both systemic sites and mucosal surfaces in mice after i.n. immunization. In the absence of any additional adjuvant, the GP nanoparticle significantly boosted antigen-specific humoral and cellular immune responses, comparable to the acknowledged potent mucosal immunomodulator CpG. The robust immune responses conferred immune protection against challenges by homologous and heterologous viruses. Additionally, the solid self-adjuvant effect of GP nanoparticles may mask the role of CpG when coincorporated. In the absence of currently approved mucosal adjuvants, GP nanoparticles can be developed into potent i.n. influenza vaccines, providing broad protection. With versatility and flexibility, the GP nanoplatform can be easily adapted for constructing mucosal vaccines for different respiratory pathogens.

Keywords: graphene oxide nanoparticles; homologous and heterologous protection; immunoenhancing effect; intranasal vaccination; recombinant protein vaccines.

Publication types

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

MeSH terms

  • Administration, Intranasal
  • Animals
  • Cell Line
  • Cross Reactions / immunology*
  • Cytokines / immunology
  • Cytokines / metabolism
  • Female
  • Graphite / chemistry
  • Graphite / immunology
  • Hemagglutinin Glycoproteins, Influenza Virus / chemistry
  • Hemagglutinin Glycoproteins, Influenza Virus / immunology
  • Humans
  • Immunity, Humoral / drug effects
  • Immunity, Humoral / immunology
  • Immunity, Mucosal / drug effects
  • Immunity, Mucosal / immunology
  • Influenza A Virus, H3N2 Subtype / drug effects
  • Influenza A Virus, H3N2 Subtype / immunology*
  • Influenza A Virus, H3N2 Subtype / physiology
  • Influenza Vaccines / administration & dosage
  • Influenza Vaccines / chemistry
  • Influenza Vaccines / immunology*
  • Influenza, Human / immunology*
  • Influenza, Human / prevention & control
  • Influenza, Human / virology
  • Mice, Inbred BALB C
  • Nanoparticles / administration & dosage
  • Nanoparticles / chemistry*
  • Oligodeoxyribonucleotides / chemistry
  • Oligodeoxyribonucleotides / immunology
  • Orthomyxoviridae Infections / immunology*
  • Orthomyxoviridae Infections / prevention & control
  • Orthomyxoviridae Infections / virology
  • Polyethyleneimine / chemistry
  • Vaccination / methods


  • CpG ODN 1826
  • Cytokines
  • Hemagglutinin Glycoproteins, Influenza Virus
  • Influenza Vaccines
  • Oligodeoxyribonucleotides
  • graphene oxide
  • Graphite
  • Polyethyleneimine