Integrin αvβ5 internalizes Zika virus during neural stem cells infection and is a target for antiviral therapy

Here, we performed the first CRISPR-Cas9 genome-wide screen in glioblastoma stem cells (GSCs) to identify factors determining ZIKV neurotropism. Using a ZIKV-ZsGreen reporter virus, a new strategy was developed to sort infection-resistant cells, expand, and enrich the resistant pool. Importantly, bioinformatics analysis and functional validation revealed integrin αvβ5 as an internalization factor for ZIKV. Expression of αvβ5 is correlated with ZIKV susceptibility in various cell lines and matched the cell tropism in developing human cerebral cortex. Blocking antibody against integrin αvβ5 but not αvβ3 efficiently inhibited ZIKV infection. Mechanistic evaluation showed that ZIKV binds to cells but fails to internalize when treated with integrin αvβ5 blocking antibody. αvβ5 directly binds to ZIKV virions, activates FAK (focal adhesion kinase), which is required for ZIKV infection. Strikingly, pharmaceutical inhibitors of αvβ5, SB273005 and cilengitide suppressed ZIKV infection at nanomolar concentrations. Finally, αvβ5 blocking antibody or inhibitors reduced ZIKV infection and alleviated ZIKV induced pathology in human neural stem cells (hNSC) and in mouse brain. This is the first study, to the best of our knowledge, identifying integrin αvβ5 is an internalization factor for ZIKV providing a new therapeutic target as well as two promising drug candidates that potentially can be used as prophylactics or treatments for ZIKV infections. Examination of sgRNA populations in ZIKV-ZsGreen negative GSCs