Long-term cellular immunity of vaccines for Zaire Ebola Virus Diseases

Nat Commun. 2024 Sep 3;15(1):7666. doi: 10.1038/s41467-024-51453-z.

Abstract

Recent Ebola outbreaks underscore the importance of continuous prevention and disease control efforts. Authorized vaccines include Merck's Ervebo (rVSV-ZEBOV) and Johnson & Johnson's two-dose combination (Ad26.ZEBOV/MVA-BN-Filo). Here, in a five-year follow-up of the PREVAC randomized trial (NCT02876328), we report the results of the immunology ancillary study of the trial. The primary endpoint is to evaluate long-term memory T-cell responses induced by three vaccine regimens: Ad26-MVA, rVSV, and rVSV-booster. Polyfunctional EBOV-specific CD4+ T-cell responses increase after Ad26 priming and are further boosted by MVA, whereas minimal responses are observed in the rVSV groups, declining after one year. In-vitro expansion for eight days show sustained EBOV-specific T-cell responses for up to 60 months post-prime vaccination with both Ad26-MVA and rVSV, with no decline. Cytokine production analysis identify shared biomarkers between the Ad26-MVA and rVSV groups. In secondary endpoint, we observed an elevation of pro-inflammatory cytokines at Day 7 in the rVSV group. Finally, we establish a correlation between EBOV-specific T-cell responses and anti-EBOV IgG responses. Our findings can guide booster vaccination recommendations and help identify populations likely to benefit from revaccination.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Antibodies, Viral / immunology
  • CD4-Positive T-Lymphocytes* / immunology
  • Cytokines / immunology
  • Cytokines / metabolism
  • Ebola Vaccines* / administration & dosage
  • Ebola Vaccines* / immunology
  • Ebolavirus* / immunology
  • Female
  • Follow-Up Studies
  • Hemorrhagic Fever, Ebola* / immunology
  • Hemorrhagic Fever, Ebola* / prevention & control
  • Humans
  • Immunity, Cellular*
  • Immunization, Secondary
  • Immunologic Memory / immunology
  • Male
  • Memory T Cells / immunology
  • Middle Aged
  • Vaccination
  • Young Adult

Substances

  • Ebola Vaccines
  • Antibodies, Viral
  • Cytokines