Zikavirus prME Envelope Pseudotyped Human Immunodeficiency Virus Type-1 as a Novel Tool for Glioblastoma-Directed Virotherapy

Glioblastoma multiforme is the most lethal type of brain tumor that is not yet curable owing to its frequent resurgence after surgery. Resistance is mainly caused by the presence of a subpopulation of tumor cells, the glioma stem cells (GSCs), which are highly resistant to radiation and chemotherapy. In 2015, Zikavirus (ZIKV)-induced microcephaly emerged in newborns, indicating that ZIKV has a specific neurotropism. Accordingly, an oncolytic tropism for infecting GSCs was demonstrated in a murine tumor model. Like other flaviviruses, ZIKV is enveloped by two proteins, prM and E. The pME expression plasmid along with the HIV-1 vector pNL Luc AM generated prME pseudotyped viral particles. Four different prME envelopes, Z1 to Z4, were cloned, and the corresponding pseudotypes, Z1- to Z4-HIVluc, produced by this two-plasmid system, were tested for entry efficiency using Vero-B4 cells. The most efficient pseudotype, Z1-HIVluc, also infected glioma-derived cell lines U87 and 86HG39. The pseudotype system was then extended by using a three-plasmid system including pME-Z1, the HIV-1 packaging plasmid psPAX2, and the lentiviral vector pLenti-luciferase-P2A-Neo. The corresponding pseudotype, designated Z1-LENTIluc, also infected U87 and 86HG39 cells. Altogether, a pseudotyped virus especially targeting glioma-derived cells might be a promising candidate for a prospective glioblastoma-directed virotherapy.