Project description:Amniotic fluid is a complex biological medium that offers mechanical protection and nutrition to the fetus, and also plays a key role in normal fetal growth, organogenesis, and potentially fetal programming. Amniotic fluid is also critically involved in longitudinally shaping the in utero milieu during pregnancy. Yet, the molecular mechanism of action by which amniotic fluid regulates fetal development is ill-defined partly due to an incomplete understanding of the evolving composition of the amniotic fluid proteome. Prior research consisting of cross-sectional studies suggests that the amniotic fluid proteome changes as pregnancy advances, yet longitudinal alterations have not been confirmed because repeated sampling is prohibitive in humans. We therefore performed serial amniocenteses at early, mid, and late gestational time-points within the same pregnancies in a rhesus macaque model. Longitudinally-collected rhesus amniotic fluid samples were paired with gestational-age matched cross-sectional human samples. Utilizing LC-MS/MS isobaric labeling quantitative proteomics, we demonstrate considerable cross-species similarity between the amniotic fluid proteomes and large scale gestational-age associated changes in protein content throughout pregnancy. This is the first study to establish a reference proteomic profile across gestation. This non-human primate model holds promise as a translational platform for amniotic fluid studies and to identify adversely affected pregnancies.
Project description:Amniotic fluid has been proposed as an easily available source of cells for numerous applications in regenerative medicine and tissue engineering. The use of amniotic fluid cells in biomedical applications necessitates their unequivocal characterization; however, the exact cellular composition of amniotic fluid and the precise tissue origins of these cells remain largely unclear. Using cells cultured from human amniotic fluid of the second trimester from a healthy fetus and fetuses with spina bifida aperta, we have performed single-cell RNA sequencing to characterize the tissue origin and marker expression of cultured amniotic fluid cells at the single-cell level. Our analysis identified nine different cell types of stromal, epithelial and immune cell phenotype, and from various fetal tissue origins, demonstrating the heterogeneity of the cultured amniotic fluid cell population at single-cell resolution. Further, our data question the presence of pluripotent stem cell populations in cultured AF, and provide a comprehensive list of markers for the characterization of its various progenitor and terminally differentiated cell types. Our study highlights the relevance of single-cell analysis approaches for the characterization of amniotic fluid cells in order to harness their full potential in biomedical research and clinical applications.
Project description:Isolation of tissue-specific fetal stem cells and derivation of primary organoids is currently limited to post-termination samples. This hampers the prenatal investigation of fetal development and congenital diseases. Therefore, novel patient-specific in vitro models are needed. To this aim, isolation and expansion of fetal stem cells during pregnancy, without the need for tissue or cellular reprogramming, would be advantageous. The amniotic fluid (AF) is a source of cells originating from multiple developing organs. Using single cell analysis, we characterised the cellular identities present in the human AF. We identified and isolated viable epithelial stem/progenitor cells of fetal gastrointestinal, renal and pulmonary origin. Upon culture, these cells formed clonal epithelial organoids, manifesting small intestine, kidney tubule and lung identity. AF organoids (AFO) exhibit transcriptomic, protein expression and functional features of their tissue of origin. With relevance for prenatal disease modelling, we derived lung organoids from the amniotic and tracheal fluid cells of Congenital Diaphragmatic Hernia (CDH) fetuses. CDH organoids show differences to non-CDH controls recapitulating some features of the disease. AFO are derived in a timeline compatible with prenatal intervention, potentially allowing investigation of therapeutic tools and regenerative medicine strategies personalised to the fetus at clinically relevant developmental stages.
Project description:Fetal wounds repair by regeneration rather than wound healing and the environment is dominated by amniotic fluid. We are looking at early transcriptional regulation of keratinocytes cultured in amniotic fluid in vitro. Keratinocytes were isolated and expanded to passage three after which they were starved in DMEM for 12h then cultured for 24h in human amniotic fluid (50%), fcs (50%) or DMEM alone for another 24h. N=2, pooled replicates per CEL-file.
Project description:Intra-amniotic infection, the invasion of microbes into the amniotic cavity resulting in an inflammatory process, is a clinical condition that can lead to adverse pregnancy outcomes for the mother and fetus as well as severe long-term neonatal morbidities. Despite much research focused on the consequences of intra-amniotic infection, there is still little knowledge about the functional roles of innate immune cells that respond to invading microbes. In the current study, we performed RNA sequencing of sorted neutrophils and monocytes/macrophages from amniotic fluid from women with intra-amniotic infection to determine the transcriptomic differences between these innate immune cells. Further, we sought to identify specific transcriptomic pathways that were significantly altered by the maternal or fetal origin of amniotic fluid neutrophils and monocytes, the presence of a severe fetal inflammatory response, and pregnancy outcome (i.e. preterm or term delivery). We showed that significant transcriptomic differences exist between amniotic fluid neutrophils and monocytes/macrophages from women with intra-amniotic infection that are indicative of the distinct roles these cells play. We also found that amniotic fluid monocytes/macrophages of fetal origin display impaired ability to clear out microbes invading the amniotic cavity compared to those of maternal origin. Notably, we demonstrate that the transcriptomic changes in amniotic fluid monocytes/macrophages are heavily associated with the severity of the fetal inflammatory response, suggesting that the trafficking of fetal neutrophils throughout the umbilical cord is partially modulated by monocytes/macrophages in the amniotic cavity. Finally, we show that amniotic fluid neutrophils and monocytes/macrophages from preterm deliveries display enhanced transcriptomic activity compared to those from term deliveries, highlighting the protective role of these innate immune cells in this vulnerable period. Collectively, these findings demonstrate the underlying complexity of local innate immune responses in women with intra-amniotic infection, and provide new insights into the functions of amniotic fluid neutrophils and monocytes in the amniotic cavity.
Project description:The goal of the experiment was to uncover novel TTTS biomarkers using microarray gene expression analysis of cell free fetal RNA from the amniotic fluid of TTTS-affected and non-affected pregnant women.
Project description:Mesenchymal stromal cells (MSC) are currently being evaluated in numerous preclinical and clinical cell-based therapy studies. Furthermore, there is an increasing interest in exploring alternative uses of these cells in disease modelling, pharmaceutical screening and regenerative medicine by applying reprogramming technologies. However, the limited availability of MSCs from various sources, restricts their use. Term amniotic fluid has been proposed as an alternative source of MSCs. Previously, only low volumes of term fluid and its cellular constituents have been collected, and current knowledge of the MSCs derived from this fluid is limited. In this study, we collected amniotic fluid at term using a novel collection system and evaluated amniotic fluid MSC content and their characteristics, including their feasibility to undergo cellular reprogramming.