FIG 1.

Tree shrew primary cells are susceptible to ZIKV infection. All primary cells were isolated from a 5-month-old tree shrew and cultured according to the standard protocol. All primary cells were infected with ZIKV at a multiplicity of infection (MOI) of 1. (A) The cytopathic effects (CPEs) in primary kidney cells (PKCs) and primary testis cells (PTCs) were assessed by imaging at 48 h postinfection (hpi). (B) Immunostaining assays were performed at 48 hpi with ZIKV-specific antibodies. Positive viral antigens are shown in green, and 4′,6-diamidino-2-phenylindole (DAPI) is shown in blue. (C) The viral loads at the indicated time points were determined by reverse transcription quantitative PCR (RT-qPCR). The dotted line indicates the detection limit of the RT-qPCR assay. (D) The mRNA levels of selected genes in infected PBMCs at the indicated time points were determined using RT-qPCR. Each assay was performed at least two times with experimental triplicates. Bar, 50 μm.