A DNA vaccine candidate expressing dengue-3 virus prM and E proteins elicits neutralizing antibodies and protects mice against lethal challenge.
In an effort to develop a suitable DNA vaccine candidate for dengue, using dengue-3 virus (DENV-3) as a prototype, the genes coding for premembrane (prM) and envelope proteins (E) were inserted into an expression plasmid. After selecting recombinant clones containing prM/E genes, protein expression in the cell monolayer was detected by indirect immunofluorescence and immunoprecipitation assays. After selecting three vaccine candidates (pVAC1DEN3, pVAC2DEN3 and pVAC3DEN3), they were analyzed in vivo to determine their ability to induce a DENV-3-specific immune response. After three immunizations, the spleens of the immunized animals were isolated, and the cells were cultivated to measure cytokine levels by ELISA and used for lymphoproliferation assays. All of the animals inoculated with the recombinant clones induced neutralizing antibodies against DENV-3 and produced a T cell proliferation response after specific stimuli. Immunized and control mice were challenged with a lethal dose of DENV-3 and observed in order to assess their survival capability. The groups that presented the best survival rate after the challenge were the animals vaccinated with the pVAC3DEN3 clones, with an 80% survival rate. Thus, these data show that we have manufactured a vaccine candidate for DENV-3 that is able to induce a specific immune response and protects mice against a lethal challenge.
De Paula
Sérgio Oliveira
SO
Laboratório de Imunovirologia Molecular, Departamento de Biologia Geral, Universidade Federal de Viçosa, Av PH Rolfs, s/n, Viçosa, Minas Gerais, CEP 36570-000, Brazil. depaula@ufv.br
Lima
Danielle Malta
DM
de Oliveira França
Rafael Freitas
RF
Gomes-Ruiz
Alessandra Cristina
AC
da Fonseca
Benedito Antônio Lopes
BA
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002522:Chlorocebus aethiops; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D003715:Dengue / Q000276:immunology / Q000401:mortality / Q000517:prevention & control*; D053059:Dengue Vaccines / Q000235:genetics / Q000276:immunology* / Q000627:therapeutic use; D003716:Dengue Virus / Q000235:genetics / Q000276:immunology*; D005260:Female; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D009500:Neutralization Tests; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology* / Q000627:therapeutic use; D014709:Vero Cells; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology*; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology*
D000914:Antibodies, Viral; D016207:Cytokines; D053059:Dengue Vaccines; C084188:E protein, Dengue virus type 3; D011994:Recombinant Proteins; D019444:Vaccines, DNA; D014759:Viral Envelope Proteins; D014764:Viral Proteins; C084187:prM protein, Dengue virus type 3