Characterization of an immunocompetent animal model for dengue virus infection

Background: Dengue is the main arbovirose that affects humans and despite its high epidemiological importance there are no effective drugs or a completely safe and widely available vaccine capable of preventing viral infection when used in endemic areas. Methods and materials: In the present study, we characterized acute, sub-lethal systemic DENV2 infection in WT B6 mice using a triple plaque-purified version of non-adapted DENV2 JHA1 strain. Results: WT B6 mice develop transient viremia, with mild dissemination to different tissues (mostly the brain), accompanied by induction of cytokine-producing DENV2-specific T cells, leading to recovery or partial lethality by encephalitis-like disease. This phenotype is much more severe in B6 mice that lack CD8 or CD27 expression, indicating than CD8 T cells are important mediators of protection in this model. Conclusion: Hence, the study shows that the C57BL/6 mouse model can be used to examine T-cell-inducing vaccine candidates for dengue disease.