Roles of PD-L1 in human adipose-derived mesenchymal stem cells under inflammatory microenvironment.

Mesenchymal stem cells (MSCs) display unique homing and immunosuppression features which make them promising candidates for cell therapy in inflammatory disorders. It is known that C-X-C chemokine receptor type 4 (CXCR4, also known as CD184) is a critical receptor implicated in MSCs migration, and the protein programmed death ligand-1 (PD-L1) is involved in MSC's immunosuppression. However, it remains unclear how the molecular mechanisms regulate PD-L1 expression for migration and immunosuppression of MSCs under the inflammatory microenvironment. In this article, we used the human adipose-derived mesenchymal stem cells (hADMSCs) treated with lipopolysaccharide (LPS) as an in vitro inflammatory model to explore the roles of PD-L1 on the migration and immunosuppression of MSC. Our results demonstrate that in hADMSCs, LPS significantly increased PD-L1 expression, which mediated the migration of the LPS-treated hADMSCs via CXCR4. In addition, we found that the increased PD-L1 expression in the LPS-treated hADMSCs inhibited B cell proliferation and immunoglobulin G secretion through nuclear factor-κB. Our study suggests that the PD-L1 plays critical roles in the homing and immunosuppression of MSCs which are a promising cell therapy to treat inflammatory diseases.

[Effects of Foliar Application of Silicon Fertilizers on Phyllosphere Bacterial Community and Functional Genes of Paddy Irrigated with Reclaimed Water].

Agricultural utilization of reclaimed water is considered to be an effective way to solve water shortage and reduce water environmental pollution. Silicon fertilizer can improve crop yield and quality and enhance crop resistance. The effect of foliar spray with silicon fertilizer on phyllosphere microbial communities remains lacking. In this study, a pot experiment was conducted to explore the effects of different types of silicon fertilizer on the composition and diversity of a phyllosphere bacterial community and the abundances of related functional genes in rice irrigated with reclaimed water. The results showed that Firmicutes, Proteobacteria, Actinobacteriota, Bacteroidota, and Verrucomicrobiota dominated the phyllosphere bacteria of rice. The relative abundance of Bacillus was higher than that of other treatments in RIS3. Reclaimed water irrigation significantly increased the relative abundances of the potential pathogens Pantoea and Enterobacter. The unclassified bacteria were also an important part of the bacterial community in the rice phyllosphere. Bacillus, Exiguobacterium, Aeromonas, and Citrobacter were significantly enriched by silicon fertilizer treatments. Functional prediction analysis showed that indicator species were mainly involved in metabolism and degradation functions, and the predicted functional groups of phyllosphere bacteria were attributed to chemoheterotrophy, aerobic chemoheterotrophy, nitrate reduction, and fermentation. Quantitative PCR results showed that AOA, AOB, and nifH genes were at low abundance levels in all treatments, and nirK genes was not significantly different among treatments. These results contribute to the in-depth understanding of the effects of foliar spray silicon fertilizer on the bacterial community structure and diversity of rice phyllosphere and provide a theoretical basis for the application of silicon fertilizer in reclaimed water irrigation agriculture.

Alizarin, an Agonist of AHR Receptor, Enhances CYP1A1 Enzyme Activity and Induces Transcriptional Changes in Hepatoma Cells.

The phytopigment alizarin was previously characterized as an anti-tumor drug owing to its antioxidant or antigenotoxic activities. However, the safety of alizarin is currently still under dispute. In this study, we explored the activity of alizarin in the AHR-CYP1A1 pathway and analyzed the transcriptional changes affected by alizarin using human hepatoma cell line HepG2-based assays. The results showed that alizarin decreased HepG2 cell viability in a dose-dependent manner, with IC50 values between 160.4 and 216.8 µM. Furthermore, alizarin significantly upregulated the expression of CYP1A1 and increased the ethoxyresorufin-O-deethylase activity. Alizarin also exhibited agonistic activity toward the AHR receptor in the XRE-mediated luciferase reporter gene assay, which was further confirmed via the molecular docking assay. In addition, the transcriptional analysis indicated that alizarin may act as a potential carcinogen through significantly enriching several items related to cancer in both DO and KEGG analysis. In brief, our findings indicated that alizarin shows agonistic activities to the AHR receptor through activating the AHR-CYP1A1 signaling pathway in HepG2 cells, which may lead to the risks for cancer developing.

Insights into the toxicities of UV-328, UV-329, UV-P in HepG2 cells and their roles in AHR-mediated pathway.

The widespread high concentrations of benzotriazole ultraviolet stabilizers (BUVSs) in many biotic and abiotic samples have raised urgent concerns of their adverse effects on environmental and human health. In this study, we investigated the toxicity of three typical BUVSs (UV-328, UV-329, UV-P) with HepG2 cells in vitro. Results indicated that the three BUVSs showed weak cytotoxicity in HepG2 cells at concentrations lower than 50 µM. Transcriptional analysis indicated that the toxic effects of the three chemicals followed the order of UV-P > UV-329 > UV-328. UV-P and UV-329 may act as potential environmental diabetogens by significantly enriching several diabetic related items in both GO and KEGG analysis. Moreover, UV-P and UV-329 significantly upregulated the expression of AHR target genes (CYP1A1, CYP1A2, UGT1A1, etc.), and increased the ethoxyresorufin-O-deethylase (EROD) activity and exhibited agonistic activity toward AHR in the XRE-mediated luciferase reporter gene assay. Molecular docking assay also indicated that UV-329 and UV-P had higher binding affinities to AHR-LBD than UV-328. In brief, our findings indicated that UV-P and UV-329 were potential agonist of AHR ligand, and may exert more toxicity than UV-328 in inducing liver toxicity.

Transcriptomic Sequencing Analysis on Key Genes and Pathways Regulating Cadmium (Cd) in Ryegrass (Lolium perenne L.) under Different Cadmium Concentrations

Perennial ryegrass (Lolium perenne L.) is an important forage grass and has the potential to be used in phytoremediation, while little information is available regarding the transcriptome profiling of ryegrass leaves in response to high levels of Cd. To investigate and uncover the physiological responses and gene expression characteristics of perennial ryegrass under Cd stress, a pot experiment was performed to study the transcriptomic profiles of ryegrass with Cd-spiked soils. Transcriptome sequencing and comparative analysis were performed on the Illumina RNA-Seq platform at different concentrations of Cd-treated (0, 50 and 500 mg·kg−1 soil) ryegrass leaves and differentially expressed genes (DEGs) were verified by RT-qPCR. The results show that high concentrations of Cd significantly inhibited the growth of ryegrass, while the lower concentrations (5 and 25 mg·kg−1) showed minor effects. The activity levels of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and malondialdehyde (MDA) increased in Cd-treated ryegrass leaves. We identified 1103 differentially expressed genes (DEGs) and profiled the molecular regulatory pathways of ryegrass leaves with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis in response to Cd stress. Cd stress significantly increased the membrane part, the metabolic process, the cellular process and catalytic activity. The numbers of unigenes related to signal transduction mechanisms, post-translational modification, replication, recombination and repair significantly increased. KEGG function annotation and enrichment analysis were performed based on DEGs with different treatments, indicating that the MAPK signaling pathway, the mRNA surveillance pathway and RNA transport were regulated significantly. Taken together, this study explores the effect of Cd stress on the growth physiology and gene level of ryegrass, thus highlighting significance of preventing and controlling heavy metal pollution in the future.

Profiling biotoxicities of hexafluoropropylene oxide trimer acid with human embryonic stem cell-based assays.

Hexafluoropropylene oxide trimer acid (HFPO-TA), an emerging replacement of perfluorooctanoic acid (PFOA), has recently been reported to be a potential environmental contaminant. Due to the similar structure to PFOA, HFPO-TA may cause comparable adverse effects on human health. Therefore, evaluating the toxic profiles of HFPO-TA has become an urgent task. In this study, we investigated the cytotoxicity and hepatoxicity of HFPO-TA using human embryonic stem cell (hESC)-based assays. Results showed that HFPO-TA reduced hESCs' viability in a dose dependent manner, and the calculated IC50 for 24, 48 and 72 hr were 222.8, 167.4, and 80.6 µmol/L, respectively. Significant intracellular ROS accumulation and mitochondrion membrane potential reduction were detected with HFPO-TA exposure, and increased apoptotic/necrotic cells were also observed in high dose of HFPO-TA treated group. Moreover, HFPO-TA at noncytotoxic concentrations also significantly impaired the functions of induced hepatocytes by diminishing cell glycogen storage ability and deregulating specific functional genes. Transcriptome sequencing analysis identified a set of hepatic associated biological processes responding to HFPO-TA exposure. PPAR was the most significantly enriched pathway. Genes including FGA, FGB, FGG, AHSG, HRG, ITIH2, ALB were characterized as hub genes by cytoHubba plug-in. These data indicated that HFPO-TA is a potential hepatotoxicant, and may not be a safe replacement for PFOA.

Advantages and prospects of stem cells in nanotoxicology.

Nanomaterials have been widely used in many fields, especially in biomedical and stem cell therapy. However, the potential risks associated with nanomaterials applications are also gradually increasing. Therefore, effective and robust toxicology models are critical to evaluate the developmental toxicity of nanomaterials. The development of stem cell research provides a new idea of developmental toxicology. Recently, many researchers actively investigated the effects of nanomaterials with different sizes and surface modifications on various stem cells (such as embryonic stem cells (ESCs), adult stem cells, etc.) to study the toxic effects and toxic mechanisms. In this review, we summarized the effects of nanomaterials on the proliferation and differentiation of ESCs, mesenchymal stem cells and neural stem cells. Moreover, we discussed the advantages of stem cells in nanotoxicology compared with other cell lines. Finally, combined with the latest research methods and new molecular mechanisms, we analyzed the application of stem cells in nanotoxicology.

The Potential Role of Cathepsin K in Non-Small Cell Lung Cancer.

(1) Background: Cathepsin K has been found overexpressed in several malignant tumors. However, there is little information regarding the involvement of Cathepsin K in non-small cell lung cancer (NSCLC). (2) Methods: Cathepsin K expression was tested in human NSCLC cell lines A549 and human embryo lung fibroblast MRC-5 cells using Western blot and immunofluorescence assay. Cathepsin K was transiently overexpressed or knocked down using transfection with a recombinant plasmid and siRNA, respectively, to test the effects on cell proliferation, migration, invasion, and on the mammalian target of rapamycin (mTOR) signaling pathway. (3) Results: Expression of Cathepsin K was increased significantly in A549 cells and diffused within the cytoplasm compared to the MRC-5 cells used as control. Cathepsin K overexpression promoted the proliferation, migration, and invasion of A549 cells, accompanied by mTOR activation. Cathepsin K knockdown reversed the above malignant behavior and inhibited the mTOR signaling activation, suggesting that Cathepsin K may promote the progression of NSCLC by activating the mTOR signaling pathway. (4) Conclusion: Cathepsin K may potentially represent a viable drug target for NSCLC treatment.

Silver nanoparticles (AgNPs) and AgNO3 perturb the specification of human hepatocyte-like cells and cardiomyocytes.

Silver nanoparticles (AgNPs) are commonly utilized industrial compounds mostly because of their antimicrobial properties. Nevertheless, our understanding of their potential developmental toxicity in humans is still limited. Embryonic stem cells (ESCs) are powerful in vitro tools for developmental toxicity assessments of chemicals. Here, we evaluated the potential developmental toxicity during early embryogenesis of AgNPs and AgNO3 with human ESC (hESC)-based differentiation systems in vitro. We found that human relevant concentrations of AgNPs and Ag ions affected the specification of two of the three primary germ layers, endoderm and mesoderm, without drastically affecting ectoderm. Furthermore, the two forms of Ag impaired the generation and functions of hepatocytes-like cells derived from endoderm, by decreasing the expression of important liver markers such as AFP, ALB, and HNF4A, and altering glycogen storage. When considering cardiac development, AgNPs and AgNO3 manifested opposite adverse effects, in that AgNPs increased while AgNO3 decreased the expression of typical cardiac markers (NKX2.5, MYH6, and ISL) in hESC-derived cardiomyocytes. In conclusion, our findings argue for a potential developmental toxicity of AgNP doses we are exposed to, or levels detected in the human body, especially at very early stages during embryogenesis, and which may not be just due to Ag leakage. Moreover, mesendoderm-derived cell types, tissues and organs may be more prone to AgNP toxicity than ectoderm lineages.

Non-cytotoxic silver nanoparticle levels perturb human embryonic stem cell-dependent specification of the cranial placode in part via FGF signaling.

Silver nanoparticles (AgNPs) are compounds used in numerous consumer products because of their desirable optical, conductive and antibacterial properties. However, several in vivo and in vitro studies have raised concerns about their potential developmental toxicity. Here, we employed a human embryonic stem cell model to evaluate the potential ectodermal toxicity of AgNPs, at human relevant concentrations. Among the four major ectodermal lineages tested, only cranial placode specification was significantly affected by AgNPs and AgNO3, morphology-wise and in the expression of specific markers, such as SIX3 and PAX6. Mechanistically, we found that the effects of AgNPs on the cranial placode differentiation were probably due to Ag ion leakage and mediated by the FGF signaling. Thus, AgNPs may have the ability to alter the early stages of embryonic development.

Bisphenol A and several derivatives exert neural toxicity in human neuron-like cells by decreasing neurite length.

Bisphenol A (BPA) and its derivatives, including bisphenols S (BPS), F (BPF), E (BPE), B (BPB), Z (BPZ), and AF (BPAF), are widely used in consumer products. Moreover, they are typically detected in the environment, food, and humans. Previous studies have linked BPA to several health risks, but it is still unclear whether BPA replacements are safe. In this study, we developed an in vitro model based on human embryonic stem cells (hESCs) to explore the potential neural toxicity of these compounds. We observed that the bisphenols affected the viability of hESCs and hESC-derived neural stem cells (NSCs) at high concentrations, with BPS being the least cytotoxic and BPAF the strongest cytotoxic compound. At human-relevant concentrations, the bisphenols did not significantly interfere with gene expression and protein levels during hESC differentiation into the neural epithelium, as well as during specification of neuron-like cells from NSCs. Nevertheless, monitoring of cell morphology changes indicated that exposure to BPA and its derivatives impaired neurite length in neuron-like cells. Thus, our findings provide insights into the molecular mechanisms of bisphenol-dependent neurotoxicity at low nanomolar levels and support the view that BPA substitutes may not be sufficiently safe for widespread use as industrial chemicals.

Typical halogenated flame retardants affect human neural stem cell gene expression during proliferation and differentiation via glycogen synthase kinase 3 beta and T3 signaling.

2',2',4,4'-tetrabromo diphenyl ether (BDE-47), one of the most abundant congeners of commercial pentaBDE utilized as flame retardants, has been phased out of production due to its potential neural toxicity and endocrine disrupting activities, and yet still present in the environment. Several alternatives to BDE-47, including tetrabromobisphenol A (TBBPA), tetrabromobisphenol S (TBBPS), tetrachlorobisphenol A (TCBPA) and decabromodiphenyl ether (BDE-209), are presently employed without restrictions and their potential toxic effects on human neural development are still unclear. In this study, we utilized a human neural stem cell (hNSC)-based system to evaluate the potential developmental neurotoxic effects of the above-mentioned five chemicals, at environment and human exposure relevant concentrations. We found that those compounds slightly altered the expression of hNSC identity markers (SOX2, SOX3 and NES), without impairing cell viability or proliferation, in part by either modulating glycogen synthase kinase 3 beta (GSK3ß) signaling (TBBPS, TCBPA and BDE-47), and slightly disturbing the NOTCH pathway (TBBPA, TBBPS and TCBPA). Moreover, the five chemicals seemed to alter hNSC differentiation by perturbing triiodothyronine (T3) cellular signaling. Thus, our findings suggest that the five compounds, especially TBBPS, TCBPA, and BDE-47, may affect hNSC self-renewal and differentiation abilities and potentially elicit neural developmental toxicity.

Toxicogenomic analyses of the effects of BDE-47/209, TBBPA/S and TCBPA on early neural development with a human embryonic stem cell in vitro differentiation system.

Flame retardants are detected in the environment worldwide, and thus pose great risks to human health. The potential effects of these chemicals on the development of the central nervous system, have recently raised public concern. In this study, to explore the toxicity of these chemicals during the early developmental stages of the human central nervous system, we induced human embryonic stem cells to differentiate into neural ectoderm in the presence of five halogenated flame retardants, BDE-47, BDE-209, TBBPA, TBBPS and TCBPA, individually or in combination. We identified a set of neural development-related biological processes that responded to these chemicals, by analyzing the whole transcriptional changes. We confirmed the RNA-seq results by qRT-PCR and found that transcription factors crucial for neural development, such as ZIC1, ZIC3, HES3, IGFBP3 and DLX5, were dysregulated by those chemicals. In addition, the five flame retardants might also influence axon growth/guidance and neuron transmission-related processes, by dysregulating genes including CNTN2, SLIT1, LRRC4C, RELN, CBLN1, CHRNB4 and GDF7. Furthermore, the chemical treatments seemed to interfere with the WNT and AHR signaling pathways. Overall, our findings revealed that BDE-209 had similar toxicity as BDE-47, whereas TBBPS and TCBPA might not be safe alternatives to TBBPA. Interestingly, we observed no obvious synergistic effects when we mixed those five flame retardants together.

Genetic diversity of diazotrophs and total bacteria in the phyllosphere of Pyrus serotina, Prunus armeniaca, Prunus avium, and Vitis vinifera.

The phyllosphere, which supports a large number of microorganisms, represents the interface between the aboveground parts of plants and air. In this study, four nifH clone libraries were constructed from the phyllosphere of Pyrus serotina (L), Vitis vinifera (P), Prunus armeniaca (X), and Prunus avium (Y). Clones related to Skermanella (L, 12.1%; X, 15.6%; Y, 62.5%; P 70.8%), Bradyrhizobium (X, 2.1%; P, 15.1%; L, 63.7%), Erwinia (X, 68.8%), Pseudomonas (L, 3.3%; P, 7.6%), and Chroococcidiopsis (P, 0.9%; L, 4.4%, X; 5.2%, Y; 19.6%) were present at high percentages, highlighting their critical role in contributing nitrogen to the phyllosphere ecosystem. The 16S rDNA sequence analysis suggested that phyllosphere-associated bacteria were affiliated with a wide range of taxa, encompassing members from Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Deltaproteobacteria, Actinobacteria, Bacteroidetes, Firmicutes, Cyanobacteria, Tenericutes, and Deinococcus-Thermus. Additionally, the abundance of the nifH gene and 16S rDNA was assessed with quantitative PCR. The number of copies of nifH and 16S rDNA ranged from 1.14 × 103 to 1.49 × 104 and from 3.72 × 106 to 7.02 × 107 copies/g fresh leaf sample, respectively. In conclusion, our work sheds light on the microbial communities of the phyllosphere that are important for plant growth. Moreover, we observed a unique composition of nitrogen-fixing bacteria in each phyllosphere sample, suggesting the existence of specific interactions between these functional microorganism and plants, which may provide information or be a reference for the development of bacterial fertilizers.

Embryonic stem cell- and transcriptomics-based in vitro analyses reveal that bisphenols A, F and S have similar and very complex potential developmental toxicities.

Bisphenol A (BPA) is a very versatile industrial chemical. Many reports have associated BPA with several health effects. Some bisphenol alternatives have been introduced to replace BPA in its many applications. However, comprehensive toxicological evaluations for these replacements are still lacking. In this study, we examined the potential effects of BPA, bisphenol F (BPF) and bisphenol S (BPS), on embryonic development with an in vitro stem cell toxicology system and transcriptomics analyses. Mouse embryonic stem cells (mESCs) were differentiated via embryoid body formation, either globally towards the three primary germ layers and their lineages, or specifically into neuroectoderm/neural progenitor cells. During the differentiation, cells were treated with BPA, BPF, BPS, or DMSO control. Samples were collected at different time points, for qRT-PCR and RNA-seq analyses. BPA, BPF and BPS disrupted many processes, during mESC global and neural differentiations, in very similar manners. In fact, at each time point the three chemicals differentially regulated analogous gene categories, particularly the ones involved in cell-matrix and cell-cell adhesion, signal transduction pathways, and medical conditions such as cardiovascular diseases and cancer. Our findings demonstrate once more then BPA substitutes may not be very safe. They potentially have a very complex developmental toxicity, similarly to BPA, and seem more toxic than BPA itself. In addition, our results reveal that stem cell-based developmental toxicity assays can be very comprehensive.

Human Pluripotent Stem Cells as Tools for Predicting Developmental Neural Toxicity of Chemicals: Strategies, Applications, and Challenges.

The human central nervous system (CNS) is very sensitive to perturbations, since it performs sophisticated biological processes and requires cooperation from multiple neural cell types. Subtle interference from exogenous chemicals, such as environmental pollutants, industrial chemicals, drug components, food additives, and cosmetic constituents, may initiate severe developmental neural toxicity (DNT). Human pluripotent stem cell (hPSC)-based neural differentiation assays provide effective and promising tools to help evaluate potential DNT caused by those toxicants. In fact, the specification of neural lineages in vitro recapitulates critical CNS developmental processes, such as patterning, differentiation, neurite outgrowth, synaptogenesis, and myelination. Hence, the established protocols to generate a repertoire of neural derivatives from hPSCs greatly benefit the in vitro evaluation of DNT. In this review, we first dissect the various differentiation protocols inducing neural cells from hPSCs, with an emphasis on the signaling pathways and endpoint markers defining each differentiation stage. We then highlight the studies with hPSC-based protocols predicting developmental neural toxicants, and discuss remaining challenges. We hope this review can provide insights for the further progress of DNT studies.

Establishment of a human embryonic stem cell-based liver differentiation model for hepatotoxicity evaluations.

The liver is one of the major targets of hormones, including thyroid hormones (THs), and many industrial chemicals, such as endocrine-disrupting chemicals. Those compounds may permeate the placenta barrier and pose a risk for embryonic development. Therefore, it is necessary to assess the toxic effects of those kind of industrial chemicals during liver development. In this study, to mimic liver specification in vitro, we differentiated human embryonic stem cells (ESCs) into functional hepatocyte-like cells. We performed this differentiation process in presence of two THs, triiodothyronine (T3) and thyroxine (T4), with the purpose of identifying biomarkers for toxicity screening. TH exposure (3, 30 and 300 nM) yielded to hepatocytes with impaired glycogen storage ability and abnormal lipid droplets' accumulation. Global gene expression analysis by RNA-seq identified a number of genes responsible for hepatic differentiation and function which were affected by 30 nM T3 and T4. Those differentially expressed genes were used to assess the potential developmental liver toxicity of two famous environmental pollutants, 2, 2, 4, 4-tetrabromodiphenyl ether (BDE-47) and decabromodiphenyl ether (BDE-209), at 10 nM to 1 µM treatments. Our findings demonstrate that BDE-47 and BDE-209, dysregulated pathways such as "chemical carcinogenesis", "steroid hormone biosynthesis" and "drug metabolism-cytochrome P450". Moreover, we were able to identify a set of 17 biomarkers, very useful to predict the potential developmental hepatotoxicity of industrial chemicals.

TBBPA and Its Alternatives Disturb the Early Stages of Neural Development by Interfering with the NOTCH and WNT Pathways.

Tetrabromobisphenol A (TBBPA), as well as its alternatives Tetrabromobisphenol S (TBBPS) and Tetrachlorobisphenol A (TCBPA), are widely used halogenated flame retardants. Their high detection rates in human breast milk and umbilical cord serum have raised wide concerns about their adverse effects on human fetal development. In this study, we evaluated the cytotoxicity and neural developmental toxicity of TBBPA, TBBPS, and TCBPA with a mouse embryonic stem cell (mESC) system, at human body fluid and environmental relevant doses. All the three compounds showed similar trends in their cytotoxic effects. However, while TBBPA and TBBPS stimulated ESC neural differentiation, TCBPA significantly inhibited neurogenesis. Mechanistically, we demonstrated that, as far as the NOTCH (positive regulator) and WNT (negative regulator) pathways were concerned, TBBPA only partially and slightly disturbed them, whereas TBBPS significantly inhibited the WNT pathway, and TCBPA down-regulated the expression of NOTCH effectors but increased the WNT signaling, actions which both inhibited neural specification. In conclusion, our findings suggest that TBBPS and TCBPA may not be safe alternatives to TBBPA, and their toxicity need to be comprehensively evaluated.

Evaluation of the early developmental neural toxicity of F-53B, as compared to PFOS, with an in vitro mouse stem cell differentiation model.

F-53B, as an alternative to the persistent organic pollutant perfluorooctane sulfonate (PFOS), is amply used in the electric plating industry. F-53B and PFOS have similar physicochemical, biochemical and physiological properties, due to the similarity in their chemical structure. Thus, they may also possess similar toxicities. Although epidemiological studies and in vivo assays have shown that prenatal exposure to PFOS may impair the development of the nervous system, toxicity data for F-53B are still scarce. In this study, we employed an embryonic stem cell (ESC) in vitro differentiation system, to detect the potential developmental neural toxicity of F-53B and PFOS, at human exposure relevant doses. We demonstrated that during early mouse ESC (mESC) neural differentiation, F-53B and PFOS disrupted the expression of neural marker genes and affected the morphology of the differentiated cells. However, the very same treatments did not cause any cytotoxic effects. In conclusion, our ESC in vitro differentiation system was able to prove for the first time that F-53B and PFOS at human exposure relevant concentrations, could alter the expression of differentiation biomarkers, indicating a potential developmental neural toxicity. Based on our findings, it is reasonable to deduce that excessive exposure to F-53B and PFOS may cause severe dysfunctions during early stages of embryo development.