Developing a pseudotyping assay for Zika virus glycoprotein

Zika virus (ZIKV) was originally described during 1947 in Uganda when it was isolated from a sentinel macaque in the forest of Zika. After its discovery, discrete outbreaks were reported in Africa and Asia, but it was until 2007 when an outbreak in the Yap Islands where it was identified as a pathogen capable of causing epidemics and became associated with microcephaly. We analysed 10 ZIKV sequences from key locations, tracking the virus’ spread through the Americas, following the Yap Island outbreak. We identified 8 mutations within the M (prM) and E proteins which may alter the tropism or entry kinetics of the virus. To test the influence of these glycoprotein mutants on virus entry we have explored lentivirus pseudotypes with a luciferase reporter to measure infectivity. So far, the model involving the use of PNL 4.3 HIV based retroviral backbone has not given favourable results so in the aim to try to improve the conditions and favour the process we tested different conditions including a matrix of concentrations between the retroviral backbone and the viral glycoprotein. The addition of other viral proteins was also tested in an effort to produce particles capable to infect the target cells.