Selection and Characterization of Single-Stranded DNA Aptamers of Diagnostic Potential against the Whole Zika Virus

Zika virus became a major public health problem in early 2015, when cases of Guillain-Barré syndrome and microcephaly were associated with viral infection. Currently, ZIKV is endemic in all tropical areas of the world, and the chance for future Zika epidemics remains very real and accurate diagnosis is crucial. The aim of this work was to select specific ssDNA aptamers that bind to the entire Zika virus and can be used to compose specific diagnostics, without cross-reactivity with other flaviviruses. Zika virus was cultivated in Vero cells and used as a target for aptamer selection. Aptamers specific for the ZIKV were selected using whole-virus SELEX, with counterselection for other flavivirus. Secondary and tertiary structures were evaluated and the molecular anchoring between the aptamers and target were simulated by the HDOCK server. Aptamer interaction was evaluated by ELISA/ELASA and the dissociation constant (Kd) was calculated by thermophoresis. Four ZIKV-specific aptamers were selected. The best two were further characterized and proved to be specific for ZIKV. Aptamers are capable of binding specifically to the ZIKV and differentiate from Dengue virus. The aptamers selected in this work can be used as capture agents in the composition of diagnostic tests to specifically detect ZIKV infection.