Heat Shock Protein 70 (Hsp70) Is Involved In The Zika Virus Cellular Infection Process

Zika virus (ZIKV) is a historically neglected flavivirus that has recently caused epidemics in the western hemisphere. ZIKV has been associated with severe symptoms including infant microcephaly and Guillain Barre syndrome, stimulating interest in understanding factors governing ZIKV infection. Heat shock protein 70 (Hsp70) has been shown to be an infection factor for multiple viruses. We investigated the role of Hsp70 in the ZIKV infection process. We localized Hsp70 protein to the Vero cell membrane surface by confocal microscopy and demonstrated that, inside the cell, there is significant co-localization between Hsp70 and ZIKV E protein. Inducing and suppressing Hsp70 expression increased and decreased ZIKV production, respectively. Antibody blocking cell surface-localized Hsp70 decreased ZIKV cell infection rates and production of infectious virus particles, as did competition with recombinant Hsp70 protein. Our data suggest that Hsp70 is an important factor in the ZIKV infection process. Understanding the interactions between Hsp70 and ZIKV may lead to novel therapeutics for ZIKV infection, particularly for pregnant women and fetuses.