Construção e avaliação do potencial protetor, em modelo murino, de diferentes construções do Vaccinia Virus Ankara Modificado (MVA) expressando a proteína E de Dengue Virus sorotipos 1, 2 e 4.

Abstract

Dengue is the main arbovirus that affecting humans and a serious public health problem. The four dengue virus serotypes (DENV1, 2, 3 and 4) are transmitted through the bite of female Aedes mosquitoes. A vaccine available worldwide has immunological gaps, which motivates further research for an effective vaccine. The Modified Vaccinia Ankara Virus (MVA) is among the most advanced and intensely studied viral vectors worldwide, and is considered as an excellent tool for vaccine generation. The aim of this work was to construct recombinant MVAs expressing the protein E of DENV1, 2 and 4 and to evaluate the protective potential of these constructs in a murine model. Synthetic genes coding for protein E from DENV1, 2 and 4 were designed, optimized, commercially obtained and subcloned into plasmid pLW44, giving rise to transfer plasmids used in the construction of recombinant viruses. Chicken embryo fibroblast cultures – CEF, or BHK-21 were infected with MVA and transfected with the transfer plasmids pLW44-DENV1, pLW44-DENV2 and pLW44-DENV4 for the construction of recombinant MVAs (rMVA). The generated rMVAs had their correct construction confirmed by PCR, sequencing and flow cytometry. The protective potential of rMVA-DENV1 was tested in C57 / BL6 mice on a homologous dose-boosting immunization schedule, followed by intracranial challenge with the corresponding DENV. Animals were immunized with 107 pfu or 108 pfu of rVA-DENV1 and challenged with DENV1 Mochizuki. During the challenge, they were monitored evaluated through a SHIRPA protocol. Based on the results we can conclude that the construction of the different recombinant viruses was effective, especially rMVA-DENV1, the only one tested for protective capacity. The data generated in this research can be added to those previously obtained for DENV3 in order to obtain a tetravalent vaccine against DENV.