Transplacental Zika virus transmission in ex vivo perfused human placentas
Fig 5
Primary Hofbauer cells are permissive for ZIKV infection and ADE of ZIKV infection.
Hofbauer cells (HBCs) and trophoblasts were isolated from term human placentas and infected with ZIKV+flavivirus naive serum (ZIKV+control) or ZIKV+DENV nAbs at an MOI of 0.5 in presence or absence of FcγR blocking antibodies and protein G, for 48 hours. A: Confocal laser scanning microscopy image of ZIKV+DENV nAbs infected HBCs and uninfected HBCs. B: Confocal laser scanning microscopy image of ZIKV+DENV nAbs infected trophoblasts and uninfected trophoblasts. HBCs were visualized by fluorescent staining for CD68, trophoblasts for cytokeratin-7 (Cyto-7), ZIKV by staining for ZIKV envelope protein (ZIKV-E) and nuclei with Hoechst 33342 staining (DNA). C: Percentage of infection of HBCs and trophoblasts was determined with confocal laser scanning microscopy. Bars represent mean+SEM. Significance was determined with a Student’s T-test. D&E: ZIKV titers were determined in supernatants of HBCs and trophoblasts. Bars represent median+95%CI. Significance was determined using the Kruskal-Wallis test followed by Dunn’s post hoc test, comparing ZIKV+DENV nAbs without block to the other conditions. F-I: Cytokines were determined in the supernatants of HBCs with a multiplex bead-based assay. Each dot represents one value of experiments performed in triplicate/quadruplicate, lines represent mean ±SEM. Significance was determined using one-way ANOVA with Dunnett’s post hoc test. N = 2–3 donors per condition for all experiments. *P<0.05, ** P<0.01, ***P<0.001, ****P<0.0001.