Washington DC: In a significant development, scientists say they have gained new insight into how the Zika virus infects the fetus, and a potential means of preventing infection.
The virus has two potential routes to the developiFetus,ng fetus: a placental route established in the first trimester, and a route across the amniotic sac that only becomes available in the second trimester, according to the study.
The scientists found that the epithelial cells of the amniotic membrane surrounding the fetus were particularly susceptible to Zika virus infection.
Zika virus also uses other receptors, including Axl and Tyro3, which are found in various placental cells. However, the investigators found that only TIM1 was strongly and consistently expressed in placental cell types throughout gestation.
TIM1 binds to phosphatidylethanolamine (PE), a membrane lipid present in the Zika virus envelope that is also present in dengue, West Nile and Ebola.
Duramycin, a 19-amino acid cyclic small molecule, binds to PE in the virion envelope, and by doing so it can block these viruses from latching onto the TIM1 receptor to get into cells.
The scientists found that duramycin blocked infection of all the placental and fetal membrane cell types they tested, including cytotrophoblasts and amniotic epithelial cells, as well as chorionic villus explants. What’s more, the infection was substantially blocked at relatively low concentrations of the drug.