Project description:To characterise the human trophoblast cells derived from human ESCs and the effects of ZIKV infection on them, we performed RNA-seq on two sets of samples: 1)human ES cell line HuES8 and the trophoblast cells differentiated. 2)trophoblast cells infected at 4 days after differentiation by MOCK and ZIKV, and harvested 72hpi. Here, we demonstrate gene expression profile of trophoblasts derived from human ESCs is similar to the trophoectoderm cells isolated from human blastocysts. And ZIKV infection on the human ESCs derived trophoblasts activated a panel of pathways, including programmed cell death.
Project description:Zika virus (ZIKV) infection during pregnancy results in an increased risk of spontaneous abortion and vertical transmission across placenta results in severe congenital defects in newborns. While the infectivity and pathological effects of ZIKV on the placental trophoblast progenitor cells in early human embryos remains largely unknown. Here, using the human trophoblast stem cells (hTSCs) isolated from human blastocyst, we showed that hTSCs were permissive to ZIKV infection, while resistance to ZIKV increased with differentiation. Combined CRISPR/Cas9-mediated gene knockout and RNA-seq assays, we demonstrated that the intrinsic expression of AXL and TIM-1, as well as the absence of potent interferon (IFN)-stimulated genes (ISGs), contributed to the high sensitivity of hTSCs to ZIKV. Furthermore, using our newly developed hTSC-derived 3 dimensional (3D) placental trophoblast organoid model, we demonstrated that ZIKV infection completely disrupted the structure of mature hTSC-organoids and inhibited syncytialization. Overall, our results clearly demonstrated that hTSCs represented the major target cells of ZIKV, and a possible reduced syncytialization may result from ZIKV infection of early developing placenta. These findings deepened our understanding of the characteristics and consequences of ZIKV infection of trophoblast stem cells in early human embryo.
Project description:To determine the effect of Zika virus infection on pre-implantation embryonic development, we performed single blastocyst RNA-Seq on MOCK and ZIKV infected embryos. ZIKV infection results in an increased risk of spontaneous abortion and poor intrauterine growth although the mechanisms underlying fetal loss remain undetermined. Little is known about the impact of ZIKV infection during the earliest stages of pregnancy, or pre- and peri-implantation, because most current studies of ZIKV infection in pregnancy models focus on post-implantation stages. Here, we demonstrate that trophectoderm cells of pre-implantation human and mouse embryos can be efficiently infected with ZIKV, and that trophectoderm can propagate virus causing cell death of neural progenitors. These findings were corroborated by our demonstration that hESC-derived trophectoderm cells are infected by ZIKV in a dose dependent manner. RNAseq of single blastocysts revealed key transcriptional changes in cellular and physiologic functions upon ZIKV infection, including nervous system development and function, prior to commitment to the neural cell lineage. Finally, the pregnancy rate of mice infected pre-implantation was > 50% lower than females infected at E4.5. These results demonstrate that pre-implantation ZIKV infection of trophectoderm leads to miscarriage or spontaneous abortion. Moreover, pre- and peri-implantation ZIKV infects trophectoderm cells that propagate virus over time causing cell death in neural progenitors. Cumulatively, these data demonstrate that vertical pre- and peri-implantation ZIKV infection of trophectoderm impairs fetal development and causes neural progenitor cell death, elucidating a previously unappreciated association of pre- and peri-implantation ZIKV infection and microcephaly.
Project description:Zika virus (ZIKV) infection of maternal and placental cells at the maternal-fetal interface is associated with a spectrum of adverse pregnancy outcomes including fetal demise and pregnancy loss. Trophoblast cell types that comprise the placenta include cytotrophoblasts, syncytiotrophoblasts (STs), and extravillous trophoblasts (EVTs). To determine which trophoblast cells are permissive to ZIKV and to understand how infection impacts cellular gene expression, we utilized a macaque in vitro trophoblast stem cell (TSC) model. TSCs were derived from primary cytotrophoblasts and represent a proliferative trophoblast that can be differentiated into STs and EVTs. TSCs and ST3Ds (STs grown in suspension) were highly permissive to infection with ZIKV strain DAK AR 41524, whereas EVTs maintained a level of resistance to productive infection. The impact of ZIKV on cellular gene expression was determined by transcriptomic and miRNAome analysis. Infection of TSCs and ST3Ds results in increased expression of immune related genes, including those in the type I and type III interferon response. ZIKV exposure impacts EV protein, mRNA, and miRNA cargo, regardless of productive infection. Altogether, these findings suggest TSCs and STs of the macaque are permissive to ZIKV infection and that EV analysis has the potential to identify ZIKV infection. These findings provide a foundation for further ZIKV study and allow for potential ZIKV infection biomarker identification in a highly translational model.
Project description:To identify the various host factors involved in ZIKV infection, we compared the transcriptional profile for ZIKV-infected human first-trimester placenta trophoblast cell (HTR8) and glioblastoma astrocytoma (U251-MG). Our results demonstrated that the common IFN, inflammatory cytokine, and chemokine production were activated upon ZIKV infection of these two cell types while serval DEGs were enriched in distinct biological processes related to the characteristics of cell types. Our findings identified multiple host factors associated with ZIKV pathogenesis and potential treatment of congenital zika syndrome (CZS)
Project description:Brain abnormalities and congenital malformations have been linked to the circulating strain of Zika virus (ZIKV) in Brazil since 2016 during the microcephaly outbreak; however, the molecular mechanisms behind several of these alterations and differential viral molecular targets have not been fully elucidated. Here we explore the proteomic alterations induced by ZIKV by comparing the Brazilian (Br ZIKV) and the African (MR766) viral strains, in addition to comparing them to the molecular responses to the Dengue virus (DENV). Neural stem cells (NSCs) derived from induced pluripotent stem (iPSCs) were cultured both as monolayers and in suspension (resulting in neurospheres), which were then infected with ZIKV (Br ZIKV or ZIKV MR766) or DENV to assess alterations within neural cells. Large-scale proteomic analyses allowed the comparison not only between viral strains but also regarding the two- and three-dimensional cellular models of neural cells derived from iPSCs, and the effects on their interaction. Altered pathways and biological processes were observed, related to cell death, cell cycle dysregulation, and neurogenesis. These results reinforce already published data and provide further information regarding the biological alterations induced by ZIKV and DENV.
Project description:We employed 3D brain organoids generated from induced human pluripotent stem cells (ihPSC) as ex vivo model of viral infection in the developing brain and utilized wild type (WT) ZIKV producing sfRNA and mutant ZIKV deficient in production of sfRNA. Global transcriptome profiling by RNA-Seq revealed that production of sfRNA affects expression of >1000 genes. We uncovered that in addition to activation of pro-apoptotic pathways, organoids infected with sfRNA-producing WT, but not sfRNA-deficient mutant ZIKV, exhibited strong down-regulation of genes involved in signaling pathways that control neuron differentiation and brain develop-ment, which indicates the requirement of sfRNA for suppression of neurodevelopment associated with ZIKV infection. Using gene set enrichment analysis and gene network reconstruction, we demonstrated that the effect of sfRNA on pathways that control brain development occurs via crosstalk between Wnt-signaling and proapoptotic pathways.
Project description:Trophoblast lineages, as the precursor of placenta, are essential for post-implantation embryo survival. However, the regulatory networks for trophoblast development remains incompletely understood. Here, we identified CITED1 as a regulator to induce trophoblast-like differentiation from mESCs. Overexpression of CITED1 in ESCs prompted differentiation towards trophoblast accompanying with elevated expression of trophoblast marker genes. To evaluate the ability of CITED1 to induce trophoblast differentiation at a genome-wide scale, we compared the global transcriptional profiles between CITED1 overexpressing cells and control ESCs by Affymetrix microarray analysis at day 1 and day 2 after transfection. We used microarrays to identify genes affected by CITED1 overexpression in mouse ESCs.