Project description:The objective of this study was to identify the tissue expression patterns and biological pathways enriched in term amniotic fluid cell-free fetal RNA by comparing functional genomic analyses of term and second-trimester amniotic fluid supernatants. There were 2,871 significantly differentially regulated genes. In term amniotic fluid, tissue expression analysis showed enrichment of salivary gland, tracheal, and renal transcripts as compared with brain and embryonic neural cells in the second trimester. Functional analysis of genes upregulated at term revealed pathways that were highly specific for postnatal adaptation such as immune function, digestion, respiration, carbohydrate metabolism, and adipogenesis. Inflammation and prostaglandin synthesis, two key processes involved in normal labor, were also activated in term amniotic fluid. This was a prospective whole genome microarray study comparing eight amniotic fluid samples collected from eight women at term who underwent prelabor cesarean delivery and eight second-trimester amniotic fluid samples from routine amniocenteses. A functional annotation tool was used to compare tissue expression patterns in term and second-trimester samples. Pathways analysis software identified physiologic systems, molecular and cellular functions, and upstream regulators that were significantly overrepresented in term amniotic fluid.
Project description:The objective of this study was to identify the tissue expression patterns and biological pathways enriched in term amniotic fluid cell-free fetal RNA by comparing functional genomic analyses of term and second-trimester amniotic fluid supernatants. There were 2,871 significantly differentially regulated genes. In term amniotic fluid, tissue expression analysis showed enrichment of salivary gland, tracheal, and renal transcripts as compared with brain and embryonic neural cells in the second trimester. Functional analysis of genes upregulated at term revealed pathways that were highly specific for postnatal adaptation such as immune function, digestion, respiration, carbohydrate metabolism, and adipogenesis. Inflammation and prostaglandin synthesis, two key processes involved in normal labor, were also activated in term amniotic fluid.
Project description:Induced pluripotent stem cells (iPSCs) with potential for therapeutic applications can be derived from somatic cells via ectopic expression of a set of limited and defined transcription factors. However, due to risks of random integration of the reprogramming transgenes into the host genome, the low efficiency of the process, and the potential risk of virally induced tumorigenicity, alternative methods have been developed to generate pluripotent cells using nonintegrating systems, albeit with limited success. Here, we show that c-KIT+ human first-trimester amniotic fluid stem cells (AFSCs) can be fully reprogrammed to pluripotency without ectopic factors, by culture on Matrigel in human embryonic stem cell (hESC) medium supplemented with the histone deacetylase inhibitor (HDACi) valproic acid (VPA). The cells share 82% transcriptome identity with hESCs and are capable of forming embryoid bodies (EBs) in vitro and teratomas in vivo. After long-term expansion, they maintain genetic stability, protein level expression of key pluripotency factors, high cell-division kinetics, telomerase activity, repression of X-inactivation, and capacity to differentiate into lineages of the three germ layers, such as definitive endoderm, hepatocytes, bone, fat, cartilage, neurons, and oligodendrocytes. We conclude that AFSC can be utilized for cell banking of patient-specific pluripotent cells for potential applications in allogeneic cellular replacement therapies, pharmaceutical screening, and disease modeling. Total RNA obtained from mid gestation human amniotic fluid cells (AFSCs/2nd trimester AFSCs), early gestation human amniotic fluid cells (eAFSCs/1st trimester AFSCs) and human embryonic stem cells (hESCs) as described in the corresponding Materials and Methods sections.
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: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:We have discovered that GBS significantly remodels its transcriptome in response to exposure to human amniotic fluid. A large number of the affected genes are of unknown function, which means that much remains to be learned about the full influence of amniotic fluid on GBS. The majority of the observed changes in transcripts affects genes involved in basic bacterial metabolism and is connected to AF composition and nutritional requirements of the bacterium. The observation that many genes encoding adhesions are down-regulated, and genes encoding known virulence factors such as a hemolysin and a potent IL-8 proteinase are up-regulated likely have consequences for the outcome of host-pathogen interactions. Streptococcus agalactiae, serotype III strain NEM316 was grown in human amniotic fluid. Samples of bacteria were collected in mid log, late log and stationary growth phases and were used for RNA isolation for microarray analysis
Project description:The second trimester fetal transcriptome can be assessed based on cell-free RNA found within the amniotic fluid supernatant. The objective of this study was to compare the suitability of two technologies for profiling the human fetal transcriptome: RNA-Seq and expression microarray. Comparisons were based on total numbers of gene detected, rank-order gene expression, and functional genomic analysis. Fewer gene transcripts were observed using RNA-Seq than microarray (4,158 vs 8,842). Correlation of total expression within each sample ranged from R=0.43 to R=0.57. On average, there was 59% concordance in gene identity among the top 10% of genes ranked by expression. The RNA-Seq data yielded more significant pathways enrichment within the ?Physiological Systems Development and Function? categories of IPA. Alternative splicing of many well-known genes, including those previously studied in fetal development, such as H19 and IGF2 is detected by RNA-Seq. Also included in this paper is discussion of the technical challenges inherent to working with cell-free fetal RNA and possible solutions. Cell-free fetal RNA from the amniotic fluid supernatant of five second trimester fetuses was divided and prepared in tandem for analysis using either the Illumina HiSeq 2000 or Affymetrix HG-U133 Plus 2.0 GeneChip microarray.
Project description:The second trimester fetal transcriptome can be assessed based on cell-free RNA found within the amniotic fluid supernatant. The objective of this study was to compare the suitability of two technologies for profiling the human fetal transcriptome: RNA-Seq and expression microarray. Comparisons were based on total numbers of gene detected, rank-order gene expression, and functional genomic analysis. Fewer gene transcripts were observed using RNA-Seq than microarray (4,158 vs 8,842). Correlation of total expression within each sample ranged from R=0.43 to R=0.57. On average, there was 59% concordance in gene identity among the top 10% of genes ranked by expression. The RNA-Seq data yielded more significant pathways enrichment within the ?Physiological Systems Development and Function? categories of IPA. Alternative splicing of many well-known genes, including those previously studied in fetal development, such as H19 and IGF2 is detected by RNA-Seq. Also included in this paper is discussion of the technical challenges inherent to working with cell-free fetal RNA and possible solutions. Cell-free fetal RNA from the amniotic fluid supernatant of five second trimester fetuses was divided and prepared in tandem for analysis using either the Illumina HiSeq 2000 or Affymetrix HG-U133 Plus 2.0 GeneChip microarray.
Project description:We used the rhesus monkey (Macaca mulatta) as our animal model for the current study with two goals: to characterize the changes in histology and gene expression from early to late gestation (prenatal uterine organogenesis) and to determine if there are effects of prenatal exposure to bisphenol A (BPA) on the developing female uterus. Pregnant rhesus monkeys carrying a female fetus (N=22) were divided into two experimental groups, based on gestational timing: 'early' (N=10) and 'late' (N=12). These groups were then equally sub-divided into control (unexposed) and BPA (exposed) groups (5 Early Control, 5 Early BPA-exposed, 6 Late Control and 6 Late BPA-exposed.) The BPA-exposed monkeys received a deuterated BPA (dBPA, CDN Isotopes, Quebec, Canada) fruit treat on a daily basis, at a dose of 400ug/kg/day). The dosing was aimed at achieving serum levels of BPA detected in adult human biomonitoring studies. The control animals received a vehicle control on a daily basis. The 'early' time period (mid-gestation) referred to gestational days 50-100, approximating the second trimester of human gestation. The fetal monkeys in the 'early' group were delivered via cesarean section on gestation day 100 and euthanized. Samples of maternal and fetal blood and amniotic fluid were obtained. Maternal and fetal weights were also recorded. The 'late' time period referred to gestational days 100-165, approximating the third trimester of human gestation. The fetal monkeys in the 'late' group were delivered vaginally and euthanized. There were five idiopathic stillbirths (2 Control, 3 BPA-exposed) in the late group. Samples of maternal and fetal blood and amniotic fluid were obtained. Maternal and fetal weights were also recorded. After delivery, the fetal uterus was excised and cut sagitally from fundus to cervix; one side was fixed for histological evaluation and the other half was frozen for analysis of gene expression by microarray. The stillbirths were excluded from the microarray.
Project description:In order to characterize the differences between second trimester Down syndrome (DS) and euploid fetuses, we compared gene expression in uncultured amniotic fluid supernatant samples. We identified individually differentially expressed genes via paired t-tests in the matched samples, and a set of differentially expressed genes on chromosome 21 using Gene Set Enrichment Analysis. Functional pathway analysis of the resulting genes highlighted the importance of oxidative stress, ion transport, and G-protein signaling in the DS fetuses. We profiled seven DS expression samples and seven controls matched for gender and approximate gestational age..