Inactivated genotype 1a, 2a and 3a HCV vaccine candidates induced broadly neutralising antibodies in mice

Garazi Pena Alzua, Anne Finne Pihl, Anna Offersgaard, Carlos Rene Duarte Hernandez, Zhe Duan, Shan Feng, Ulrik Fahnøe, Christina Sølund, Nina Weis, Mansun Law, Jannick C. Prentoe, Jan Pravsgaard Christensen, Jens Bukh, Judith Margarete Gottwein*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

11 Citations (Scopus)
34 Downloads (Pure)

Abstract

Objective: A prophylactic vaccine is needed to control the HCV epidemic, with genotypes 1-3 causing >80% of worldwide infections. Vaccine development is hampered by HCV heterogeneity, viral escape including protection of conserved neutralising epitopes and suboptimal efficacy of HCV cell culture systems. We developed cell culture-based inactivated genotype 1-3 HCV vaccine candidates to present natively folded envelope proteins to elicit neutralising antibodies. Design: High-yield genotype 1a, 2a and 3a HCV were developed by serial passage of TNcc, J6cc and DBN3acc in Huh7.5 cells and engineering of acquired mutations detected by next-generation sequencing. Neutralising epitope exposure was determined in cell-based neutralisation assays using human monoclonal antibodies AR3A and AR4A, and polyclonal antibody C211. BALB/c mice were immunised with processed and inactivated genotype 1a, 2a or 3a viruses using AddaVax, a homologue of the licenced adjuvant MF-59. Purified mouse and patient serum IgG were assayed for neutralisation capacity; mouse IgG and immune-sera were assayed for E1/E2 binding. Results: Compared with the original viruses, high-yield viruses had up to ∼1000 fold increased infectivity titres (peak titres: 6-7 log10 focus-forming units (FFU)/mL) and up to ∼2470 fold increased exposure of conserved neutralising epitopes. Vaccine-induced IgG broadly neutralised genotype 1-6 HCV (EC50: 30-193 μg/mL; mean 71 μg/mL), compared favourably with IgG from chronically infected patients, and bound genotype 1-3 E1/E2; immune-sera endpoint titres reached up to 32 000. Conclusion: High-yield genotype 1-3 HCV could be developed as basis for inactivated vaccine candidates inducing broadly neutralising antibodies in mice supporting further preclinical development.

Original languageEnglish
JournalGut
Volume72
Issue number3
Pages (from-to)560-572
ISSN0017-5749
DOIs
Publication statusPublished - 2023

Bibliographical note

Publisher Copyright:
© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Keywords

  • chronic viral hepatitis
  • HCV
  • hepatitis C
  • immune response
  • molecular biology

Cite this