Mucosal CD8+ T cell responses induced by an MCMV based vaccine vector confer protection against influenza challenge

PLoS Pathog. 2019 Sep 16;15(9):e1008036. doi: 10.1371/journal.ppat.1008036. eCollection 2019 Sep.

Abstract

Cytomegalovirus (CMV) is a ubiquitous β-herpesvirus that establishes life-long latent infection in a high percentage of the population worldwide. CMV induces the strongest and most durable CD8+ T cell response known in human clinical medicine. Due to its unique properties, the virus represents a promising candidate vaccine vector for the induction of persistent cellular immunity. To take advantage of this, we constructed a recombinant murine CMV (MCMV) expressing an MHC-I restricted epitope from influenza A virus (IAV) H1N1 within the immediate early 2 (ie2) gene. Only mice that were immunized intranasally (i.n.) were capable of controlling IAV infection, despite the greater potency of the intraperitoneally (i.p.) vaccination in inducing a systemic IAV-specific CD8+ T cell response. The protective capacity of the i.n. immunization was associated with its ability to induce IAV-specific tissue-resident memory CD8+ T (CD8TRM) cells in the lungs. Our data demonstrate that the protective effect exerted by the i.n. immunization was critically mediated by antigen-specific CD8+ T cells. CD8TRM cells promoted the induction of IFNγ and chemokines that facilitate the recruitment of antigen-specific CD8+ T cells to the lungs. Overall, our results showed that locally applied MCMV vectors could induce mucosal immunity at sites of entry, providing superior immune protection against respiratory infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Intranasal
  • Amino Acid Sequence
  • Animals
  • CD8-Positive T-Lymphocytes / immunology*
  • Cell Line
  • Chemokines / biosynthesis
  • Epitopes, T-Lymphocyte / administration & dosage
  • Epitopes, T-Lymphocyte / genetics
  • Epitopes, T-Lymphocyte / immunology
  • Female
  • Gene Products, env / administration & dosage
  • Gene Products, env / genetics
  • Gene Products, env / immunology
  • Genetic Vectors
  • Humans
  • Immunity, Mucosal*
  • Influenza A Virus, H1N1 Subtype / genetics
  • Influenza A Virus, H1N1 Subtype / immunology
  • Influenza Vaccines / administration & dosage
  • Influenza Vaccines / genetics
  • Influenza Vaccines / immunology*
  • Influenza, Human / immunology
  • Influenza, Human / prevention & control
  • Lung / immunology
  • Lung / virology
  • Mice
  • Mice, Inbred BALB C
  • Muromegalovirus / genetics
  • Muromegalovirus / immunology*
  • NIH 3T3 Cells
  • Peptide Fragments / administration & dosage
  • Peptide Fragments / genetics
  • Peptide Fragments / immunology
  • Respiratory Mucosa / immunology
  • Respiratory Mucosa / virology
  • Vaccines, Synthetic / administration & dosage
  • Vaccines, Synthetic / genetics
  • Vaccines, Synthetic / immunology

Substances

  • Chemokines
  • Epitopes, T-Lymphocyte
  • Gene Products, env
  • Influenza Vaccines
  • Peptide Fragments
  • Vaccines, Synthetic
  • peptide fragment P828