Recombinant HIV-1 vaccine candidates based on replication-defective flavivirus vector

Sci Rep. 2019 Dec 27;9(1):20005. doi: 10.1038/s41598-019-56550-4.

Abstract

Multiple approaches utilizing viral and DNA vectors have shown promise in the development of an effective vaccine against HIV. In this study, an alternative replication-defective flavivirus vector, RepliVax (RV), was evaluated for the delivery of HIV-1 immunogens. Recombinant RV-HIV viruses were engineered to stably express clade C virus Gag and Env (gp120TM) proteins and propagated in Vero helper cells. RV-based vectors enabled efficient expression and correct maturation of Gag and gp120TM proteins, were apathogenic in a sensitive suckling mouse neurovirulence test, and were similar in immunogenicity to recombinant poxvirus NYVAC-HIV vectors in homologous or heterologous prime-boost combinations in mice. In a pilot NHP study, immunogenicity of RV-HIV viruses used as a prime or boost for DNA or NYVAC candidates was compared to a DNA prime/NYVAC boost benchmark scheme when administered together with adjuvanted gp120 protein. Similar neutralizing antibody titers, binding IgG titers measured against a broad panel of Env and Gag antigens, and ADCC responses were observed in the groups throughout the course of the study, and T cell responses were elicited. The entire data demonstrate that RV vectors have the potential as novel HIV-1 vaccine components for use in combination with other promising candidates to develop new effective vaccination strategies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS Vaccines / immunology*
  • Animals
  • Antibodies, Neutralizing / immunology
  • Chlorocebus aethiops
  • Cross Reactions
  • Defective Viruses / genetics*
  • Female
  • Flavivirus / genetics*
  • Genetic Vectors*
  • HIV Infections / virology
  • HIV-1 / immunology*
  • HIV-1 / pathogenicity
  • Macaca mulatta
  • Mice
  • Mice, Inbred BALB C
  • Vaccines, Synthetic / immunology*
  • Vero Cells
  • Virulence

Substances

  • AIDS Vaccines
  • Antibodies, Neutralizing
  • Vaccines, Synthetic