Discovery and Verification of Extracellular miRNA Biomarkers for Non-invasive Prediction of Pre-eclampsia in Asymptomatic Women.

Development of effective prevention and treatment strategies for pre-eclampsia is limited by the lack of accurate methods for identification of at-risk pregnancies. We performed small RNA sequencing (RNA-seq) of maternal serum extracellular RNAs (exRNAs) to discover and verify microRNAs (miRNAs) differentially expressed in patients who later developed pre-eclampsia. Sera collected from 73 pre-eclampsia cases and 139 controls between 17 and 28 weeks gestational age (GA), divided into separate discovery and verification cohorts, are analyzed by small RNA-seq. Discovery and verification of univariate and bivariate miRNA biomarkers reveal that bivariate biomarkers verify at a markedly higher rate than univariate biomarkers. The majority of verified biomarkers contain miR-155-5p, which has been reported to mediate the pre-eclampsia-associated repression of endothelial nitric oxide synthase (eNOS) by tumor necrosis factor alpha (TNF-α). Deconvolution analysis reveals that several verified miRNA biomarkers come from the placenta and are likely carried by placenta-specific extracellular vesicles.

Epidural pneumorrhachis, a rare complication of asthma exacerbation.

Introduction: An association between pneumorrhachis and asthma exacerbation is uncommon. However, we present a clinical case involving a patient with exacerbated asthma, subcutaneous emphysema, spontaneous pneumomediastinum (SPM), and pneumorrhachis. Case study: The patient was an 18-year-old male with asthma since childhood who only relied on salbutamol to control his asthma symptoms. Results: The patient suddenly experienced dyspnea, chest tightness, and paroxysmal coughing, which prompted him to visit the emergency department. Upon arrival, subcutaneous emphysema was detected on the face, neck, thorax, and left forearm. Chest X-ray showed air in the mediastinum, neck, left supraclavicular region, and chest, all of which were verified by a computed tomography scan that also revealed air in the epidural region. At the hospital, his treatment focused on preventing asthma exacerbation and managing associated symptoms. Conclusion: When a patient has asthma exacerbation that is accompanied by SPM and extensive emphysema, the presence of epidural pneumorrhachis should not be overlooked.

Maternal obesity and sex-specific differences in placental pathology.

OBJECTIVE: Adverse effects of obesity have been linked to inflammation in various tissues, but studies on placental inflammation and obesity have demonstrated conflicting findings. We sought to investigate the influence of pregravid obesity and fetal sex on placental histopathology while controlling for diabetes and hypertension. METHODS: Placental histopathology focusing on inflammatory markers of a cohort of normal weight (BMI = 20-24.9) and obese (BMI ≥ 30) patients was characterized. Demographic, obstetric and neonatal variables were assessed. RESULTS: 192 normal and 231 obese women were included. Placental characteristics associated with obesity and fetal sex independent of diabetes and hypertension were placental disc weight >90(th) percentile, decreased placental efficiency, chronic villitis (CV), fetal thrombosis, and normoblastemia. Additionally, female fetuses of obese mothers had higher rates of CV and fetal thrombosis. Increasing BMI increased the risk of normoblastemia and CV. The final grade and extent of CV was significantly associated with obesity and BMI, but not fetal gender. Finally, CV was less common in large-for-gestation placentas. CONCLUSIONS: Maternal obesity results in placental overgrowth and fetal hypoxia as manifested by normoblastemia; it is also associated with an increased incidence of CV and fetal thrombosis, both more prevalent in female placentas. We have shown for the first time that the effect of maternal obesity on placental inflammation is independent of diabetes and hypertension, but significantly affected by fetal sex. Our data also point to the intriguing possibility that CV serves to normalize placental size, and potentially fetal growth, in the setting of maternal obesity.

p63 inhibits extravillous trophoblast migration and maintains cells in a cytotrophoblast stem cell-like state.

Proper differentiation of placental epithelial cells, called trophoblast, is required for implantation. Early during placentation, trophoblast cell columns help anchor the developing embryo in the uterine wall. Although proximally continuous with villous cytotrophoblast (CTB) distally, these cells differentiate into invasive extravillous trophoblast. We previously reported that p63, a p53 family member, is highly expressed in proliferative villous CTB and required for induction of the trophoblast lineage in human pluripotent stem cells. We now further explore its function in human trophoblast by using both primary CTB from the early placenta and established trophoblast cell lines. We show that p63 is expressed in epidermal growth factor receptor-positive CTB and that its expression decreases with differentiation into HLA-G(+) extravillous trophoblast. In trophoblast cell lines, p63 is expressed in JEG3 cells but absent from HTR8 cells. Overexpression of p63 in both cell lines enhances cell proliferation and significantly reduces cell migration; conversely, down-regulation of p63 in JEG3 cells reduces cell proliferation and restores cell migration. Analysis of epithelial-to-mesenchymal transition, cell adhesion, and matrix degradation pathways shows that p63 blocks epithelial-to-mesenchymal transition, promotes a CTB-specific cell adhesion profile, and inhibits expression of matrix metalloproteinases. Taken together, these data show that p63 maintains the proliferative CTB state, at least partially through regulation of epithelial-to-mesenchymal transition, cell adhesion, and matrix degradation pathways.

BMP4-directed trophoblast differentiation of human embryonic stem cells is mediated through a ΔNp63+ cytotrophoblast stem cell state.

The placenta is a transient organ that is necessary for proper fetal development. Its main functional component is the trophoblast, which is derived from extra-embryonic ectoderm. Little is known about early trophoblast differentiation in the human embryo, owing to lack of a proper in vitro model system. Human embryonic stem cells (hESCs) differentiate into functional trophoblast following BMP4 treatment in the presence of feeder-conditioned media; however, this model has not been widely accepted, in part owing to a lack of proof for a trophoblast progenitor population. We have previously shown that p63, a member of the p53 family of nuclear proteins, is expressed in proliferative cytotrophoblast (CTB), precursors to terminally differentiated syncytiotrophoblast (STB) in chorionic villi and extravillous trophoblast (EVT) at the implantation site. Here, we show that BMP4-treated hESCs differentiate into bona fide CTB by direct comparison with primary human placental tissues and isolated CTB through gene expression profiling. We show that, in primary CTB, p63 levels are reduced as cells differentiate into STB, and that forced expression of p63 maintains cyclin B1 and inhibits STB differentiation. We also establish that, similar to in vivo events, hESC differentiation into trophoblast is characterized by a p63(+)/KRT7(+) CTB stem cell state, followed by formation of functional KLF4(+) STB and HLA-G(+) EVT. Finally, we illustrate that downregulation of p63 by shRNA inhibits differentiation of hESCs into functional trophoblast. Taken together, our results establish that BMP4-treated hESCs are an excellent model of human trophoblast differentiation, closely mimicking the in vivo progression from p63(+) CTB stem cells to terminally differentiated trophoblast subtypes.