Project description:During pregnancy, trophoblast cells in the placenta are the only fetal cells in direct contact with the maternal blood and decidua. They have many functions, including transport of nutrients and oxygen, remodelling the uterine arteries, and communicating with maternal cells. Despite their importance in development and in the success of pregnancy, little is known about human trophoblast progenitors and their differentiation. We identify a proliferative trophoblast niche at the base of cytotrophoblast cell columns in first trimester placentas that is characterised by integrin α2 (ITGA2) expression. Pulse-chase experiments with 5-Iodo-2′-deoxyuridine (IdU) imply that these cells can contribute to both villous and extravillous lineages. Importantly, these cells can be isolated by ITGA2 using flow cytometry and express genes from both VCT and EVT. Microarray shows that they display a unique gene signature including NOTCH signalling and mesenchymal characteristics. ITGA2 allows for the first time the study of a pure population of trophoblast progenitor cells.
Project description:Cytotrophoblast (CTB) are bipotent progenitor epithelial cells of the human placenta, which can differentiate into invasive extravillous trophoblast (EVT) and multinucleated syncytiotrophoblast (STB). Trophoblast stem cells (TSC) have also been shown to be bipotential. In this study, we set out to probe the transcriptional diversity of first trimester CTB and compare TSC to various subgroups of CTB. We performed single-cell RNA sequencing on six normal placentae, four 6-week placentae, two of which were separated into basal and chorionic fractions prior to sequencing, and two 13-week placentae. We also sequenced three TSC lines, derived from 6-8 week placentae, to evaluate similarities and differences between primary CTB and TSC. CTB clusters displayed notable distinctions based on gestational age, with 6-week placentae showing enrichment for specific CTB subtypes, further influenced by origin from the basal or chorionic plate. Differential expression analysis of CTB from basal versus chorionic plate highlighted pathways associated with proliferation, unfolded protein response, and oxidative phosphorylation. We identified trophoblast states representing initial progenitor CTB, precursor STB, precursor and mature EVT, and multiple CTB subtypes. CTB progenitors were enriched at 6-weeks, with basal plate cells biased toward EVT, and chorionic plate cells toward STB, precursors. Clustering and trajectory inference analysis indicated that TSC were most like EVT precursor cells, with only a small percentage of TSC on the pre-STB differentiation trajectory. This was confirmed by flow cytometric analysis of 6 different TSC lines, which showed uniform expression of proximal column markers ITGA2 and ITGA5. Additionally, we found that only ITGA5+ CTB could be plated in 2D, and these cells formed only EVT upon spontaneous differentiation. Our findings suggest that distinct CTB states exist in different regions of the placenta as early as six weeks gestation and that current TSC lines most closely resemble ITGA5+ CTB, biased toward the EVT lineage.
Project description:Cytotrophoblast (CTB) are bipotent progenitor epithelial cells of the human placenta, which can differentiate into invasive extravillous trophoblast (EVT) and multinucleated syncytiotrophoblast (STB). Trophoblast stem cells (TSC) have also been shown to be bipotential. In this study, we set out to probe the transcriptional diversity of first trimester CTB and compare TSC to various subgroups of CTB. We performed single-cell RNA sequencing on six normal placentae, four 6-week placentae, two of which were separated into basal and chorionic fractions prior to sequencing, and two 13-week placentae. We also sequenced three TSC lines, derived from 6-8 week placentae, to evaluate similarities and differences between primary CTB and TSC. CTB clusters displayed notable distinctions based on gestational age, with 6-week placentae showing enrichment for specific CTB subtypes, further influenced by origin from the basal or chorionic plate. Differential expression analysis of CTB from basal versus chorionic plate highlighted pathways associated with proliferation, unfolded protein response, and oxidative phosphorylation. We identified trophoblast states representing initial progenitor CTB, precursor STB, precursor and mature EVT, and multiple CTB subtypes. CTB progenitors were enriched at 6-weeks, with basal plate cells biased toward EVT, and chorionic plate cells toward STB, precursors. Clustering and trajectory inference analysis indicated that TSC were most like EVT precursor cells, with only a small percentage of TSC on the pre-STB differentiation trajectory. This was confirmed by flow cytometric analysis of 6 different TSC lines, which showed uniform expression of proximal column markers ITGA2 and ITGA5. Additionally, we found that only ITGA5+ CTB could be plated in 2D, and these cells formed only EVT upon spontaneous differentiation. Our findings suggest that distinct CTB states exist in different regions of the placenta as early as six weeks gestation and that current TSC lines most closely resemble ITGA5+ CTB, biased toward the EVT lineage.
Project description:Transcriptional profiling comparison of human primary villous trophoblast and extra-villous trophoblast (VT and EVT respectively) cells, isolated from the placenta at 8 to 12 weeks gestation, with complimentary transcriptional profiling of choriocarcinoma cell lines JEG-3 and JAR. Based on phenotypic markers, JEG is frequently used as a model for EVT and JAR is used as a model for VT.
Project description:This study aims to compare in vivo human trophoblast differentiation into EVTs to different in vitro trophoblast organoids using single-cell and single-nuclei RNA sequencing. The study includes two type of systems: human primary trophoblast organoids (PTO) and trophoblast stem cells (TSCs). Trophoblast stem cell (TSC) lines BTS5 and BTS11 derived by Okae and colleagues were grown as described previously (Okae et al. 2018) and together with EVT media. Primary trophoblast organoids (PTO) were grown and differentiated into EVT as previously described by Turco & Sheridan (Turco et al 2018; Sheridan et al 2020). This study shows that the main regulatory programs mediating EVT invasion in vivo are preserved in in vitro models of EVT differentiation from primary trophoblast organoids and trophoblast stem cells.
Project description:Invasive extravillous trophoblasts (EVTs) of the human placenta are critically involved in successful pregnancy outcome since they remodel the uterine spiral arteries to increase blood flow and oxygen delivery to the placenta and the developing fetus. To gain more insights into their biological role different primary cell culture models are commonly utilised. However, access to early placental tissue may be limited and primary trophoblasts rapidly cease proliferation in vitro impairing genetic manipulation. Hence, trophoblastic cell lines have been widely used as surrogates to study EVT function. Although the cell lines share some molecular marker expression with their primary counterpart, it is unknown to what extent they recapture the invasive phenotype of EVT. Therefore, we here report the first thorough GeneChip analyses of SGHPL-5, HTR-8/SVneo, BeWo, JEG-3 and the novel ACH-3P trophoblast cells in comparison to previously analysed primary villous cytrophoblasts and extravillous trophoblasts. To identify EVT-specific gene expression signatures in trophoblast cell lines, we calcuted differentially expressed genes between pre-defined groups based on the distinct origins of the five trophoblast cell lines under investigation. Comparison 1 comprised EVT, HTR-8/Svneo and SGHPL-5 vs choriocarcinoma cells (ACH-3P, BeWo, JEG-3). Comparison 2 comprised EVT, ACH-3P, BeWo, JEG-3 vs extravillous trophoblast cell lines (HTR-8/SVneo, SGHPL-5).
Project description:Comparison of genes associated with the EMT between undifferentiated cytotrophoblast cells (CTB) and differentiated extravillous trophoblast cells (EVT) from third trimester human placenta. Cells isolated from control (placenta previa) and cases (preeclampsia). Cells isolated by immunomagnetic separation using anti-integrin beta4 antibody to purify CTB and anti-HLA-G antibody to purify EVT.
Project description:Comparison of genes associated with the EMT between cytotrophoblast cells (CTB) and extravillous trophoblast cells (EVT) from normal third trimester placenta and abnormally invasive placenta (AIP)
Project description:We used trophoblast organoids differentiating to extravillous trophoblast (EVT) to study the effects of key cytokines secreted by uterine Natural Killer (uNK) cells on EVT behaviour. Specifically, we exposed the organoids to four uNK-derived cytokines (CSF1, CSF2, XCL1, CCL5) and collected cells at different time points along the EVT differentiation pathway for scRNA-seq. We observe enhanced EVT differentiation in cytokine-treated organoids demonstrated by the increased proportion of late EVT subtypes and regulation of related pathways such as epithelial-mesenchymal transition. Moreover, uNK cytokines affect other processes important during early pregnancy including dampening of inflammatory and adaptive immune responses, regulation of blood flow, and placental access to nutrients.
Project description:During pregnancy, normal extravillous trophoblast (EVT) invade the endomyometrium of the maternal uterus and remodel the spiral arteries to control blood supply and nutrient transfer. Recent reports have described first trimester EVT as polyploid and senescent. Here we extend these earlier reports by performing comprehensive profiling of the genomic organization and transcriptome of first trimester EVT and term EVT. We define pathways and gene regulatory networks involved in both initial differentiation and maturation of this important trophoblast lineage at the maternal-fetal interface. Our results suggest that like first trimester EVT, term EVT undergo senescence and endoreduplication, are primarily tetraploid, and lack high rates of copy number variations. Additionally, we have highlighted senescence and polyploidy-related genes, pathways, networks, and transcription factors that appeared to be important in normal EVT differentiation and maturation and have validated a critical role for the unfolded protein response in EVT differentiation.