DNA Vaccines Against Dengue Virus Based on the ns1 Gene: The Influence of Different Signal Sequences on the Protein Expression and Its Correlation to the Immune Response Elicited in Mice

Virology. 2007 Feb 20;358(2):413-23. doi: 10.1016/j.virol.2006.08.052. Epub 2006 Oct 3.

Abstract

We analyzed four DNA vaccines based on DENV-2 NS1: pcENS1, encoding the C-terminal from E protein plus the NS1 region; pcENS1ANC, similar to pcENS1 plus the N-terminal sequence from NS2a (ANC); pcTPANS1, coding the t-PA signal sequence fused to NS1; and pcTPANS1ANC, similar to pcTPANS1 plus the ANC sequence. The NS1 was detected in lysates and culture supernatants from pcTPANS1-, pcENS1- and pcENS1ANC-transfected cells and not in cells with pcTPANS1ANC. Only the pcENS1ANC leads the expression of NS1 in plasma membrane, confirming the importance of ANC sequence for targeting NS1 to cell surface. High levels of antibodies recognizing conformational epitopes of NS1 were induced in mice immunized with pcTPANS1 and pcENS1, while only few pcENS1ANC-inoculated animals presented detectable anti-NS1 IgG. Protection against DENV-2 was verified in pcTPANS1- and pcENS1-immunized mice, although the plasmid pcTPANS1 induced slight higher protective immunity. These plasmids seem to activate distinct patterns of the immune system.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Viral / blood
  • Antigens, Viral / genetics
  • Antigens, Viral / immunology*
  • Antigens, Viral / metabolism
  • Dengue / immunology*
  • Dengue / prevention & control*
  • Dengue Vaccines / administration & dosage*
  • Dengue Vaccines / genetics
  • Dengue Virus / immunology*
  • Immunization*
  • Injections, Intramuscular
  • Mice
  • Mice, Inbred BALB C
  • Plasmids / genetics
  • Plasminogen Activators / genetics
  • Vaccines, DNA / administration & dosage
  • Vaccines, DNA / genetics
  • Viral Envelope Proteins / genetics
  • Viral Envelope Proteins / immunology
  • Viral Nonstructural Proteins / genetics
  • Viral Nonstructural Proteins / immunology*
  • Viral Nonstructural Proteins / metabolism

Substances

  • Antibodies, Viral
  • Antigens, Viral
  • Dengue Vaccines
  • NS1 protein, Dengue virus type 2
  • Vaccines, DNA
  • Viral Envelope Proteins
  • Viral Nonstructural Proteins
  • Plasminogen Activators