Fig. 1.

ZIKV AF and ZIKV AS differentially infect and impair the RPE. IPSC-derived-RPE were infected with both ZIKV strains at MOI 0.1 over different time periods. (A) Viral titers in the supernatants of RPE grown in 96 well plates at various times post-infection were assayed by the TCID 50 method. Results are expressed as mean ± SEM of 3 independent experiments and each time point was compared between strains using an unpaired t-test, *p < .05, **p < .01. (B) Transepithelial resistance (TER) of mock (control, CT)- or ZIKV-infected RPE grown on cell culture inserts was measured at various dpi. Each point represents the mean ± SEM of 3 independent experiments. (C) Viral titers from apical and basal compartments of RPE grown on cell culture inserts at 4 dpi. Results are expressed as mean ± SEM of 3 independent experiments and analyzed using an unpaired t-test, *p < .05, ***p < .001 (ZIKV AF compared to ZIKV AS). (D-E) Mock- and ZIKV-infected RPE grown on cell culture insert were fixed at 11 dpi. Indirect immunofluorescence studies were used to label actin (green), ZIKV (pan-flavi, magenta), ZO-1 (D, cyan) or β-catenin (E, cyan); as well as nuclei (DAPI, blue). Representative images of 2 independent experiments are shown. Scale bars 20 μm. (F) Western blot analysis of the expression of junction (ZO-1, N-Cadherin and β-catenin) and RPE (MERTK and CRALBP) markers in mock- and ZIKV-infected RPE at 11 dpi. Representative images are shown. The quantification of the expression of these markers, as a function of GAPDH expression, is expressed as means ± SEM of 3 experiments *p < .05, **p < .01, ***p < .001.