Trophoblast stem cell-based organoid models of the human placental barrier.

Human placental villi have essential roles in producing hormones, mediating nutrient and waste exchange, and protecting the fetus from exposure to xenobiotics. Human trophoblast organoids that recapitulate the structure of villi could provide an important in vitro tool to understand placental development and the transplacental passage of xenobiotics. However, such organoids do not currently exist. Here we describe the generation of trophoblast organoids using human trophoblast stem (TS) cells. Following treatment with three kinds of culture medium, TS cells form spherical organoids with a single outer layer of syncytiotrophoblast (ST) cells that display a barrier function. Furthermore, we develop a column-type ST barrier model based on the culture condition of the trophoblast organoids. The bottom membrane of the column is almost entirely covered with syndecan 1-positive ST cells. The barrier integrity and maturation levels of the model are confirmed by measuring transepithelial/transendothelial electrical resistance (TEER) and the amount of human chorionic gonadotropin. Further analysis reveals that the model can be used to derive the apparent permeability coefficients of model compounds. In addition to providing a suite of tools for the study of placental development, our trophoblast models allow the evaluation of compound transfer and toxicity, which will facilitate drug development.

Modeling embryo-endometrial interface recapitulating human embryo implantation.

The initiation of human pregnancy is marked by the implantation of an embryo into the uterine environment; however, the underlying mechanisms remain largely elusive. To address this knowledge gap, we developed hormone-responsive endometrial organoids (EMO), termed apical-out (AO)-EMO, which emulate the in vivo architecture of endometrial tissue. The AO-EMO comprise an exposed apical epithelium surface, dense stromal cells, and a self-formed endothelial network. When cocultured with human embryonic stem cell-derived blastoids, the three-dimensional feto-maternal assembloid system recapitulates critical implantation stages, including apposition, adhesion, and invasion. Endometrial epithelial cells were subsequently disrupted by syncytial cells, which invade and fuse with endometrial stromal cells. We validated this fusion of syncytiotrophoblasts and stromal cells using human blastocysts. Our model provides a foundation for investigating embryo implantation and feto-maternal interactions, offering valuable insights for advancing reproductive medicine.

CRISPR screening in human trophoblast stem cells reveals both shared and distinct aspects of human and mouse placental development.

The placenta serves as the interface between the mother and fetus, facilitating the exchange of gases and nutrients between their separate blood circulation systems. Trophoblasts in the placenta play a central role in this process. Our current understanding of mammalian trophoblast development relies largely on mouse models. However, given the diversification of mammalian placentas, findings from the mouse placenta cannot be readily extrapolated to other mammalian species, including humans. To fill this knowledge gap, we performed CRISPR knockout screening in human trophoblast stem cells (hTSCs). We targeted genes essential for mouse placental development and identified more than 100 genes as critical regulators in both human hTSCs and mouse placentas. Among them, we further characterized in detail two transcription factors, DLX3 and GCM1, and revealed their essential roles in hTSC differentiation. Moreover, a gene function-based comparison between human and mouse trophoblast subtypes suggests that their relationship may differ significantly from previous assumptions based on tissue localization or cellular function. Notably, our data reveal that hTSCs may not be analogous to mouse TSCs or the extraembryonic ectoderm (ExE) in which in vivo TSCs reside. Instead, hTSCs may be analogous to progenitor cells in the mouse ectoplacental cone and chorion. This finding is consistent with the absence of ExE-like structures during human placental development. Our data not only deepen our understanding of human trophoblast development but also facilitate cross-species comparison of mammalian placentas.

Development of a lip vermilion epithelium reconstruction model using keratinocytes from skin and oral mucosa.

Lip vermilion is unique and can be distinguished from the adjacent skin and oral mucosa. However, because of the lack of appropriate evaluation tools, skin and/or oral mucosa substitutes such as in vitro vermilion epithelial models have been used for lip product testing. We aimed to develop and characterize a lip vermilion epithelium reconstruction model (LVERM) using skin and oral keratinocytes. LVERM was manufactured by co-culturing primary skin and oral keratinocytes, using a device that allowed the separation of cell seeding, and created an intercalated cell-free zone, referred to as the vermilion part. After removing the device, LVERM construction was completed in 8 days, in a submerged condition. Subsequently, they were placed in an air-liquid interface for 7 days. To determine the epithelial characteristics of LVERM, keratin 2e (KRT2) and small proline-rich protein 3 (SPRR3) expression patterns were examined. The in vivo expression profiles of KRT2 and SPRR3 genes in vermilion were also examined. We found that a continuous multi-layered epithelium was generated in the LVERM that exhibited ortho- and para-keratinization in the skin and oral mucosa parts, respectively. Although an intermediate keratinization pattern was observed in the vermilion part, KRT2 and SPRR3 were co-expressed in the suprabasal layer, consistent with the expression pattern of a single vermilion epithelial model. Clustering analysis revealed that KRT2 and SPRR3 gene expression in vermilion was location-dependent within the sample. Therefore, LVERM can be used as an evaluation tool for lip products and has great importance in innovative approaches for cosmetic testing.

Ten-year follow-up of infliximab treatment for uveitis in Behçet disease patients: A multicenter retrospective study.

Purpose: To evaluate 10-year outcome of infliximab (IFX) treatment for uveitis in Behçet disease (BD) patients using a standardized follow-up protocol. Design: Retrospective longitudinal cohort study. Participants: 140 BD uveitis patients treated with IFX enrolled in our previous study. Methods: Medical records were reviewed for demographic information, duration of IFX treatment, number of ocular attacks before IFX initiation, best corrected visual acuity (VA) at baseline and 1, 2, 3, 4, 5, and 10 years after IFX initiation, uveitis recurrence after IFX initiation and main anatomical site, concomitant therapies, and adverse events (AEs). Main outcome measures: 10-year IFX continuation rate and change in LogMAR VA. Results: Of 140 BD patients, 106 (75.7%) continued IFX treatment for 10 years. LogMAR VA improved gradually after initiation of IFX, and the improvement reached statistical significance from 2 years of treatment. Thereafter, significant improvement compared with baseline was maintained until 10 years, despite a slight deterioration of logMAR VA from 5 years. However, eyes with worse baseline decimal VA < 0.1 showed no significant improvement from baseline to 10 years. Uveitis recurred after IFX initiation in 50 patients (recurrence group) and did not recur in 56 (non-recurrence group). Ocular attacks/year before IFX initiation was significantly higher in the recurrence group (2.82 ± 3.81) than in the non-recurrence group (1.84 ± 1.78). In the recurrence group, uveitis recurred within 1 year in 58% and within 2 years in 74%. Seventeen patients (34%) had recurrent anterior uveitis, 17 (34%) had posterior uveitis, and 16 (32%) had panuveitis, with no significant difference in VA outcome. In addition, logMAR VA at 10 years did not differ between the recurrence and non-recurrence groups. AEs occurred among 43 patients (30.7%), and 24 (17.1%) resulted in IFX discontinuation before 10 years. Conclusions: Among BD patients with uveitis who initiated IFX, approximately 75% continued treatment for 10 years, and their VA improved significantly and was maintained for 10 years. Uveitis recurred in one-half of the patients, but visual acuity did not differ significantly from the patients without recurrence.

Genomic imprinting in human placentation.

Background: Genomic imprinting (GI) is a mammalian-specific epigenetic phenomenon that has been implicated in the evolution of the placenta in mammals. Methods: Embryo transfer procedures and trophoblast stem (TS) cells were used to re-examine mouse placenta-specific GI genes. For the analysis of human GI genes, cytotrophoblast cells isolated from human placental tissues were used. Using human TS cells, the biological roles of human GI genes were examined. Main findings: (1) Many previously identified mouse GI genes were likely to be falsely identified due to contaminating maternal cells. (2) Human placenta-specific GI genes were comprehensively determined, highlighting incomplete erasure of germline DNA methylation in the human placenta. (3) Human TS cells retained normal GI patterns. (4) Complete hydatidiform mole-derived TS cells were characterized by aberrant GI and enhanced trophoblastic proliferation. The maternally expressed imprinted gene p57KIP2 may be responsible for the enhanced proliferation. (5) The primate-specific microRNA cluster on chromosome 19, which is a placenta-specific GI gene, is essential for self-renewal and differentiation of human TS cells. Conclusion: Genomic imprinting plays diverse and important roles in human placentation. Experimental analyses using TS cells suggest that the GI maintenance is necessary for normal placental development in humans.

The microRNA cluster C19MC confers differentiation potential into trophoblast lineages upon human pluripotent stem cells.

The first cell fate commitment during mammalian development is the specification of the inner cell mass and trophectoderm. This irreversible cell fate commitment should be epigenetically regulated, but the precise mechanism is largely unknown in humans. Here, we show that naïve human embryonic stem (hES) cells can transdifferentiate into trophoblast stem (hTS) cells, but primed hES cells cannot. Our transcriptome and methylome analyses reveal that a primate-specific miRNA cluster on chromosome 19 (C19MC) is active in naïve hES cells but epigenetically silenced in primed ones. Moreover, genome and epigenome editing using CRISPR/Cas systems demonstrate that C19MC is essential for hTS cell maintenance and C19MC-reactivated primed hES cells can give rise to hTS cells. Thus, we reveal that C19MC activation confers differentiation potential into trophoblast lineages on hES cells. Our findings are fundamental to understanding the epigenetic regulation of human early development and pluripotency.

The human vermilion surface contains a rich amount of cholesterol sulfate than the skin.

BACKGROUND: The vermilion of the human lip presents characteristic features and undergoes aging faster than the skin. Therefore, knowledge of the vermilion surface-specific functional molecules is important to understand lip aging and formulate lip care products. Previously, we analyzed the free fatty acids distributions and showed that docosahexaenoic acid highly accumulated in the vermilion's epithelium than in the skin. OBJECTIVE: We aimed to explore the functional molecules other than the free fatty acids on the vermilion's surface. METHODS: Human lip tissues from children and tape-stripped samples from smooth and rough lips of adults were measured by desorption electrospray ionization-mass spectrometry imaging (DESI-MSI). RESULTS: DESI-MSI of children's lip sections revealed a major distribution of five phospholipid species in the viable layer, but not in the superficial area, of both the vermilion and the skin than that in the underlying tissue. Interestingly, a remarkably higher distribution of cholesterol sulfate was observed in the vermilion's superficial area compared to that in the skin in all subjects under this study. Furthermore, DESI-MSI of tape-stripped lip samples showed an overall higher accumulation of cholesterol sulfate in the stratum corneum of the rough lips than that in the smooth lips. CONCLUSION: Our study concluded that cholesterol sulfate has a characteristic distribution to the vermilion's surface and showed an association with the roughness of the lip.

Linoleic acid and squalene are oxidized by discrete oxidation mechanisms in human sebum.

Previous studies suggest that squalene (SQ) in sebum is oxidized by a photooxidation mechanism (i.e., singlet oxygen oxidation) to create SQ hydroperoxide (SQOOH), a compound that causes adverse skin conditions. However, oxidation of other lipids in sebum, such as linoleic acid (LA), has not been fully understood. Elucidating their oxidation, especially its mechanisms, may lead to a further understanding of the relationship between sebum oxidation and skin conditions. In this study, using HPLC-MS/MS, we aimed to detect LA hydroperoxide (LAOOH) directly from sebum and identify the oxidation mechanism of LA in sebum through analysis of LAOOH isomers. We developed extraction and HPLC-MS/MS analysis conditions that can sufficiently quantify each LAOOH isomer in sebum. Using this method, LAOOH was detected in samples from healthy individuals, demonstrating the presence of LAOOH in human sebum. Moreover, isomer analysis of LAOOH and SQOOH indicated that LA and SQ are oxidized in sebum by discrete oxidation mechanisms (LA oxidized by free radical oxidation, whereas SQ oxidized by singlet oxygen oxidation). Such results may further lead to the development of mechanism-specific ways to prevent oxidation of sebum via a selection of appropriate antioxidants, ultimately leading to the promotion of skin health.

Comparison between the effects of normal saline with and without heparin for the prevention and management of arterial catheter occlusion: a triple-blinded randomized trial.

PURPOSE: We aimed to compare the effects of saline with and without heparin on the catheter-occlusion rate and coagulation-related blood test results for the management of arterial catheters among patients admitted to a short-term intensive care unit postoperatively. METHODS: This prospective, triple-blinded, randomized controlled study recruited patients aged 20-90 years scheduled to undergo radial arterial catheter insertion and postoperative intensive care unit admission between February and August 2019. Patients were randomly allocated to two groups (1:1 ratio) depending on the use of heparin: study (normal saline with heparin, 3000 units to 500 ml of normal saline) and control (normal saline without heparin) groups with arterial catheters. The allocated management method was employed immediately after intensive care unit admission. Occlusion assessment (every 12 h), arterial blood gas tests (every 6 h), and blood sample collection (every 24 h) were performed. The occlusion of arterial catheter was assessed using occlusion rate, and blood test results were assessed using a linear mixed model. RESULTS: There were 147 patients in the arterial catheter groups. There were no significant differences in occlusion rates and changes in platelet counts and activated partial thromboplastin time between the groups with arterial (p = 0.98, 0.16, and 0.32, respectively) catheters during the first 6 days after intensive care unit admission. CONCLUSION: Normal saline with and without heparin showed similar efficiency for both the prevention of occlusion and the results of coagulation.

Unique features and emerging in vitro models of human placental development.

BACKGROUND: The placenta is an essential organ for the normal development of mammalian fetuses. Most of our knowledge on the molecular mechanisms of placental development has come from the analyses of mice, especially histopathological examination of knockout mice. Choriocarcinoma and immortalized cell lines have also been used for basic research on the human placenta. However, these cells are quite different from normal trophoblast cells. METHODS: In this review, we first provide an overview of mouse and human placental development with particular focus on the differences in the anatomy, transcription factor networks, and epigenetic characteristics between these species. Next, we discuss pregnancy complications associated with abnormal placentation. Finally, we introduce emerging in vitro models to study the human placenta, including human trophoblast stem (TS) cells, trophoblast and endometrium organoids, and artificial embryos. MAIN FINDINGS: The placental structure and development differ greatly between humans and mice. The recent establishment of human TS cells and trophoblast and endometrial organoids enhances our understanding of the mechanisms underlying human placental development. CONCLUSION: These in vitro models will greatly advance our understanding of human placental development and potentially contribute to the elucidation of the causes of infertility and other pregnancy complications.

Melanophilin Accelerates Insulin Granule Fusion without Predocking to the Plasma Membrane.

Direct observation of fluorescence-labeled secretory granule exocytosis in living pancreatic ß-cells has revealed heterogeneous prefusion behaviors: some granules dwell beneath the plasma membrane before fusion, while others fuse immediately once they are recruited to the plasma membrane. Although the former mode seems to follow sequential docking-priming-fusion steps as found in synaptic vesicle exocytosis, the latter mode, which is unique to secretory granule exocytosis, has not been explored well. Here, we show that melanophilin, one of the effectors of the monomeric guanosine-5'-triphosphatase Rab27 on the granule membrane, is involved in such an accelerated mode of exocytosis. Melanophilin-mutated leaden mouse and melanophilin-downregulated human pancreatic ß-cells both exhibit impaired glucose-stimulated insulin secretion, with a specific reduction in fusion events that bypass stable docking to the plasma membrane. Upon stimulus-induced [Ca2+]i rise, melanophilin mediates this type of fusion by dissociating granules from myosin-Va and actin in the actin cortex and by associating them with a fusion-competent, open form of syntaxin-4 on the plasma membrane. These findings provide the hitherto unknown mechanism to support sustainable exocytosis by which granules are recruited from the cell interior and fuse promptly without stable predocking to the plasma membrane.

Glycerophospholipid profile alterations are associated with murine muscle-wasting phenotype.

INTRODUCTION: Phospholipids are essential components of cellular membranes and are closely associated with cellular functions, but relationships involving skeletal muscle phospholipid profiles and their physiological phenotypes have remained unclear. METHODS: We carried out comprehensive phospholipid analyses using liquid chromatography-tandem mass spectrometry to determine the phospholipid profiles of skeletal muscles derived from muscle-wasting mouse models, including denervated and Duchenne muscular dystrophy mouse models (mdx) as well as rescued mdx mice expressing truncated dystrophin. RESULTS: Consistent phosphatidylcholine and phosphatidylethanolamine alterations in skeletal muscles isolated from denervated and mdx mice were observed. Notably, the levels of these phospholipids binding polyunsaturated fatty acids were reduced in denervated and mdx muscles. Moreover, rescuing the mdx pathology by expressing truncated dystrophin led to the restoration of phospholipid profiles. DISCUSSION: Our findings support the hypothesis that phospholipid profiles of the skeletal muscle may be associated with skeletal muscle function.

Exophilin-5 regulates allergic airway inflammation by controlling IL-33-mediated Th2 responses.

A common variant in the RAB27A gene in adults was recently found to be associated with the fractional exhaled nitric oxide level, a marker of eosinophilic airway inflammation. The small GTPase Rab27 is known to regulate intracellular vesicle traffic, although its role in allergic responses is unclear. We demonstrated that exophilin-5, a Rab27-binding protein, was predominantly expressed in both of the major IL-33 producers, lung epithelial cells, and the specialized IL-5 and IL-13 producers in the CD44hiCD62LloCXCR3lo pathogenic Th2 cell population in mice. Exophilin-5 deficiency increased stimulant-dependent damage and IL-33 secretion by lung epithelial cells. Moreover, it enhanced IL-5 and IL-13 production in response to TCR and IL-33 stimulation from a specific subset of pathogenic Th2 cells that expresses a high level of IL-33 receptor, which exacerbated allergic airway inflammation in a mouse model of asthma. Mechanistically, exophilin-5 regulates extracellular superoxide release, intracellular ROS production, and phosphoinositide 3-kinase activity by controlling intracellular trafficking of Nox2-containing vesicles, which seems to prevent the overactivation of pathogenic Th2 cells mediated by IL-33. This is the first report to our knowledge to establish the significance of the Rab27-related protein exophilin-5 in the development of allergic airway inflammation, and provides insights into the pathophysiology of asthma.

Pharmacokinetic and pharmacodynamic considerations in antimicrobial therapy for sepsis.

Introduction: Antimicrobial dose optimization for the treatment of sepsis remains challenging because of dynamic pharmacokinetic alterations and physiological/pathological responses of the host. Subtherapeutic plasma levels of antimicrobials are commonly observed in patients with sepsis, which potentially leads to both treatment failure and emergence of antimicrobial resistance. The knowledge of antimicrobial pharmacokinetics and pharmacodynamics is helpful in order to tailor antimicrobial dosing strategies.Areas covered: This narrative review summarizes pharmacokinetic alterations of antimicrobial agents and provides useful information on antimicrobial dose optimization. Literature was searched using PubMed database, focusing on pharmacokinetics and pharmacodynamics of antibacterial and antifungal agents in sepsis.Expert opinion: In patients with sepsis, increased volume of distribution and variable changes in renal clearance are the two major factors for antimicrobial pharmacokinetic alterations. Traditional 'one-dose-fits-all' dosing strategy is not suitable for patients with sepsis and hence individualized antimicrobial dosing adjustment is preferable. In general, the initial dose of hydrophilic antimicrobials such as ß-lactams, aminoglycosides, and vancomycin should be given at a high dose regardless of renal function. Improved methods of drug administration (e.g. extended/continuous infusion of ß-lactams) help to increase the chance of pharmacodynamic target attainment. The use of therapeutic drug monitoring should be considered where available.