(A) HeLa cells were plated at equal numbers and infected 24 hr later with Zika virus MR766 (Uganda, 1947) at an MOI of 0.2. At 48 hr after infection, the cells were fixed, permeabilized, and immunostained for the viral envelope (E) protein using monoclonal antibody 4G2 (green). The nuclei of the cells were also stained for DNA with Hoechst 33342 dye (blue). Imaging analysis software was used to determine the percentage infection (numbers shown ± SD) and the number of nuclei. 4× magnification.

(B) HeLa cell lines were plated at equal numbers and infected 24 hr later with Zika virus strain MR766 or FSS13025 at an MOI of 1. 3 days later, the cells were incubated with Cell Titer Glo and the relative light units were recorded and normalized to the control shScramble uninfected samples.

(C) Immunoblots of the lysates from the cells used in (A) and (B) using the indicated antibodies. Actin serves as a loading control. kDa, kilodalton.

Values in (A) and (B) indicate the mean of n = 3 independent experiments ± SD. ∗p ≤ 0.05 (Student’s t test).