Strategies to improve the immunogenicity of prM+E dengue virus type-2 DNA vaccine

Asian Pac J Allergy Immunol. 2017 Mar;35(1):11-19. doi: 10.12932/AP0728.


Background: An important goal for dengue vaccines is to induce a high and durable level of neutralizing antibody.

Objective: Three strategies were investigated for improving the immunogenicity of a prM+E dengue serotype 2 (DENV-2) DNA vaccine: 1) expression in two different plasmids; 2) adjustment of dose; and, 3) introduction of the E sequence of Japanese encephalitis virus (JEV) at the carboxy-terminal portion of DENV-2 E.

Method: Expression cassettes were designed to encode a full-length prM+E sequence of DENV-2 virus employing human-preferred codons (D2prMEopt), or a chimeric prM+E sequence in which the 100-residue carboxy-terminal region of E was derived from JEV (D2prMEJE20opt). pHIS and pCMVkan in the presence and absence of CpG motif, respectively, were used for cassette expression. The immunogenicity was compared in mice.

Results: Three injections of full-length-D2prMEopt in pHIS and pCMVkan induced a comparable neutralizing antibody titer at post-week-2-injection and post-week-4-injection. The 100-μg DNA dose induced a numerically but not statistically higher neutralizing antibody titer than the 10-μg dose. The chimeric-D2prMEJE20opt produced higher extracellular prM and E protein levels in transfected Vero cells, but had a tendency to induce a lower neutralizing antibody titer in mice when compared with the full-length-D2prMEopt. To optimize the immunogenicity of D2prMEopt-DNA candidate, both expression plasmids can be used to generate reproducible high neutralizing titer. A higher dose of DNA immunogen may induce a higher neutralizing antibody response.

Conclusion: The strategy of the C-terminal region chimeric counterpart with JE20 did not improve but may have reduced the induction of neutralizing antibodies.

MeSH terms

  • Animals
  • Antibodies, Neutralizing / immunology
  • Antibodies, Viral / immunology*
  • Dengue Vaccines / administration & dosage
  • Dengue Vaccines / immunology*
  • Dengue Virus / immunology
  • Encephalitis Virus, Japanese / immunology
  • Fluorescent Antibody Technique
  • Humans
  • Immunoblotting
  • Injections, Jet
  • Mice
  • Vaccines, DNA / administration & dosage
  • Vaccines, DNA / immunology
  • Viral Envelope Proteins / immunology*


  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Dengue Vaccines
  • Vaccines, DNA
  • Viral Envelope Proteins
  • E protein TH Sman, Dengue virus