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Wilson's disease (WD) is a copper metabolic disorder caused by a defective ATP7B function. Conventional therapies cause severe side effects and significant variation in efficacy, according to cohort studies. Thus, exploring new therapeutic approaches to prevent progression to liver failure is urgent. To study the physiology and pathology of WD, immortalized cell lines and rodent WD models have been used conventionally; however, a large gap remains among different species as well as in genetic backgrounds among individuals. We generated induced pluripotent stem cells (iPSCs) from four WD patients carrying compound heterozygous mutations in the ATP7B gene. ATP7B loss- and gain-of-functions were further manifested with ATP7B-deficient iPSCs and heterozygously corrected R778L WD patient-derived iPSCs using CRISPR-Cas9-based gene editing. Although the expression of ATP7B protein varied among WD-specific hepatocytes differentiated from these iPSCs, the expression and secretion of ceruloplasmin (Cp), a downstream copper carrier in plasma, were consistently decreased in WD patient-derived and ATP7B-deficient hepatocytes. A transcriptome analysis detected abnormalities in the retinoid signaling pathway and lipid metabolism in WD-specific hepatocytes. Drug screening using WD patient-derived hepatocytes identified retinoids as promising candidates for rescuing Cp secretion. All-trans retinoic acid also alleviates reactive oxygen species production induced by lipid accumulation in WD-specific hepatocytes treated with oleic acid. These patient-derived iPSC-based hepatic models function as effective platforms for the development of potential therapeutics for hepatic steatosis in WD and other fatty liver diseases.
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Degeneração Hepatolenticular , Humanos , Degeneração Hepatolenticular/tratamento farmacológico , Degeneração Hepatolenticular/genética , Ceruloplasmina/genética , Ceruloplasmina/metabolismo , Cobre/metabolismo , Retinoides/metabolismo , Retinoides/uso terapêutico , ATPases Transportadoras de Cobre/genética , Hepatócitos/metabolismo , Estresse Oxidativo , MutaçãoRESUMO
Type 1 diabetes (T1D) is an autoimmune disease characterized by the immune system's failure to maintain self-tolerance, resulting in the autoimmune destruction of pancreatic beta cells. Although T1D has conventionally been viewed as a T-cell-dominant disease, recent research has emphasized the contribution of B cells in the onset of the disease. However, the mechanism underlying aberrant B cell responses remains unknown. B cell metabolism is a crucial prerequisite for B cell function and the development of adaptive immune responses. Here, we investigated the metabolic features of B cells, first in a cross-sectional cohort and subsequently in non-obese diabetic (NOD) mice, and revealed that there is an increased frequency of high-glucose-avidity (2-NBDGhigh) B cell population that may contribute to T1D progression. Further characterization of the metabolic, transcriptional and functional phenotype of B cells in NOD mice found that elevated glucose avidity is associated with a greater capacity for co-stimulation, proliferation and inflammatory cytokine production. Mechanistically, elevated Myc signaling orchestrated the glucose metabolism and the pro-inflammatory response of B cells in T1D. In vitro experiments demonstrated that pharmacological inhibition of glucose metabolism using metformin and 2-DG reduced pro-inflammatory cytokine production and B cell proliferation. Moreover, the combination of these inhibitors successfully delayed insulitis development, onset of diabetes, and improved high blood glucose levels in streptozotocin (STZ)-induced diabetic mice model. Taken together, our work has uncovered these high-glucose-avidity B cells as novel adjuvant diagnostic and therapeutic targets for T1D.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Humanos , Camundongos , Animais , Camundongos Endogâmicos NOD , Estudos Transversais , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/uso terapêutico , Transdução de Sinais , Citocinas , GlucoseRESUMO
In this paper, the authors report the fabrication of a sensitive deep ultraviolet (DUV) photodetector by using an individual GaSe nanobelt with a thickness of 52.1 nm, which presents the highest photoresponse at 265 nm illumination with a responsivity and photoconductive gain of about 663 A W-1 and 3103 at a 3 V bias, respectively, comparable to or even better than other reported devices based on conventional wide bandgap semiconductors. According to the simulation, this photoelectric property is associated with the wavelength-dependent absorption coefficient of the GaSe crystal, for which incident light with shorter wavelengths will be absorbed near the surface, while light with longer wavelengths will have a larger penetration depth, leading to a blueshift of the absorption edge with decreasing thickness. Further finite element method (FEM) simulation reveals that the relatively thin GaSe nanobelt exhibits an enhanced transversal standing wave pattern compared to its thicker counterpart at a wavelength of 265 nm, leading to an enhanced light-matter interaction and thereby more efficient photocurrent generation. The device can also function as an effective image sensor with acceptable spatial resolution. This work will shed light on the facile fabrication of a high-performance DUV photodetector from non-ultrawide bandgap semiconductors.
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This work reports the design of a wavelength sensor composed of two identical perovskite (FA0.85 Cs0.15 PbI3 ) photodetectors (PDs) that are capable of discriminating incident wavelength in a quantitative way. Due to strong wavelength-dependent absorption coefficient, the penetration depth of the photons in the FA0.85 Cs0.15 PbI3 nanofilms increases with the increasing wavelength, leading to a gradual decrease of photo-generated current for PD1, but an increase of photocurrent in PD2, according to the theoretical simulation of Technology Computer Aided Design. This special evolution of photo-generated current as a function of wavelength facilitates the quantitative determination of the wavelength since the current ratio of both PDs monotonously decreases with the increase of wavelength from 265 to 810 nm. The average absolute error and the average relative error are estimated to be 7.6 nm and 1.68%, respectively, which are much better than other semiconductors materials-based wavelength sensors previously reported. It is believed that the present perovskite film-based wavelength sensor will have potential application in the future color/spectrum optoelectronic devices.
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To evaluate the safety and efficacy in terms of infarct-related artery (IRA) patency of prourokinase (proUK) injection within 6 h after symptom onset in patients with ST-elevation myocardial infarction (STEMI). A total of 1851 patients with acute myocardial infarction were enrolled to receive thrombolytic therapy with proUK. Qualifying patients were injected with 20 mg proUK intravenously followed by intravenous infusion of 30 mg proUK within 30 min. IRA was evaluated by coronary angiography at 120 min after thrombolysis. The efficacy and safety of proUK thrombolysis were analyzed in all the enrolled patients. Successful clinical reperfusion was observed in 1580 patients (85.4%). The number of leads with ST segment elevation and the amplitude of ST segment elevation were significantly reduced within 24 h after thrombolytic therapy with proUK. Eighty-three patients (4.48%) had died by the end of follow-up (7 days after thrombolysis), and the incidences of post-infarction angina, re-infarction or reocclusion, and emergency revascularization were 15.2, 4.21, and 8.27%, respectively. The most common bleeding complication was subcutaneous or mucosal bleeding and the incidence of intracranial hemorrhage was as lower as 0.32%. The fibrinolysis therapy with proUK is efficient and safe with very low rate of bleeding complications. It provides an alternative treatment options for STEMI patients especially in settings where primary PCI cannot be offered in a timely manner.
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Eletrocardiografia , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagem , Adolescente , Adulto , Idoso , Angiografia Coronária , Relação Dose-Resposta a Droga , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Resultado do Tratamento , Adulto JovemRESUMO
The effective isolation of rare target cells, such as circulating tumor cells, from whole blood is still challenging due to the lack of a capturing surface with strong target-binding affinity and non-target-cell resistance. Here we present a solution leveraging the flexibility of bacterial virus (phage) nanofibers with their sidewalls displaying target circulating tumor cell-specific aptamers and their ends tethered to magnetic beads. Such flexible phages, with low stiffness and Young's modulus, can twist and adapt to recognize the cell receptors, energetically enhancing target cell capturing and entropically discouraging non-target cells (white blood cells) adsorption. The magnetic beads with flexible phages can isolate and count target cells with significant increase in cell affinity and reduction in non-target cell absorption compared to magnetic beads having rigid phages. This differentiates breast cancer patients and healthy donors, with impressive area under the curve (0.991) at the optimal detection threshold (>4 target cells mL-1). Immunostaining of captured circulating tumor cells precisely determines breast cancer subtypes with a diagnostic accuracy of 91.07%. Our study reveals the power of viral mechanical attributes in designing surfaces with superior target binding and non-target anti-fouling.
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Neoplasias da Mama , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Neoplasias da Mama/virologia , Feminino , Aptâmeros de Nucleotídeos/metabolismo , Nanofibras/química , Linhagem Celular Tumoral , Bacteriófagos/genéticaRESUMO
Extracellular vesicles (EVs) are nanoscale extracellular particles that have received widespread scientific attention for carrying a variety of biomolecules such as nucleic acids and proteins and participating in the process of intercellular information exchange, making them become a research hotspot due to their potential diagnostic value. Breast cancer is the leading cause of cancer-related death in women, approximately 90% of patient deaths are due to metastasis complications. Brain metastasis is an important cause of mortality in breast cancer patients, about 10-15% of breast cancer patients will develop brain metastasis. Therefore, early prevention of brain metastasis and the development of new treatments are crucial. Small EVs have been discovered to be involved in the entire process of breast cancer brain metastasis (BCBM), playing an important role in driving organ-specific metastasis, forming pre-metastatic niches, disrupting the blood-brain barrier, and promoting metastatic tumor cell proliferation. We summarize the mechanisms of small EVs in the aforementioned pathological processes at the cellular and molecular levels, and anticipate their potential applications in the treatment of breast cancer brain metastasis, with the hope of providing new ideas for the precise treatment of breast cancer brain metastasis.
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Autoimmune diseases are heterogeneous disorders believed to stem from the immune system's inability to distinguish between auto- and foreign- antigens. B lymphocytes serve a crucial role in humoral immunity as they generate antibodies and present antigens. Dysregulation of B cell function induce the onset of autoimmune disorders by generating autoantibodies and pro-inflammatory cytokines, resulting in an imbalance in immune regulation. New research in immunometabolism shows that cellular metabolism plays an essential role in controlling B lymphocytes immune reactions by providing the energy and substrates for B lymphocytes activation, differentiation, and function. However, dysregulated immunometabolism lead to autoimmune diseases by disrupting self-tolerance mechanisms. This review summarizes the latest research on metabolic reprogramming of B lymphocytes in autoimmune diseases, identifying crucial pathways and regulatory factors. Moreover, we consider the potential of metabolic interventions as a promising therapeutic strategy. Understanding the metabolic mechanisms of B cells brings us closer to developing novel therapies for autoimmune disorders.
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Doenças Autoimunes , Humanos , Doenças Autoimunes/terapia , Linfócitos B , Autoanticorpos , Imunidade Humoral , Transdução de SinaisRESUMO
Although recent advances in genome editing technology with homology-directed repair have enabled the insertion of various reporter genes into the genome of mammalian cells, the efficiency is still low due to the random insertion of donor vectors into the host genome. To efficiently select knocked-in cells without random insertion, we developed the "double-tk donor vector system," in which the expression units of the thymidine kinase of herpes simplex virus (HSV-tk) are placed on both outer sides of homology arms. This system is superior in enriching knocked-in human induced pluripotent stem cells (hiPSCs) than conventional donor vector systems with a single or no HSV-tk cassette. Using this system, we efficiently generated fluorescent reporter knockin hiPSCs targeting POU5F1 (OCT3/4), EEF1A1, H2BC21 (H2B clustered histone 21), ISL1, and MYH7 genes. These results indicate that the double-tk donor vector system enables efficient selection of knocked-in hiPSCs carrying reporter proteins.
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Células-Tronco Pluripotentes Induzidas , Animais , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Simplexvirus , Edição de Genes , Genes Homeobox , MamíferosRESUMO
Innovations in synthetic chemistry have a profound impact on the drug discovery process, and will always be a necessary driver of drug development. As a result, it is of significance to develop novel simple and effective synthetic installation of medicinal modules to promote drug discovery. Herein, we have developed a NaClO-mediated cross installation of indoles and azoles, both of which are frequently encountered in drugs and natural products. This effective toolbox provides a convenient synthetic route to access a library of N-linked 2-(azol-1-yl) indole derivatives, and can be used for late-stage modification of drugs, natural products and peptides. Moreover, biological screening of the library has revealed that several adducts showed promising anticancer activities against A549 and NCI-H1975 cells, which give us a hit for anticancer drug discovery.
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Azóis , Produtos Biológicos , Indóis , Descoberta de DrogasRESUMO
Different Sn/H-zeolite (ß, MOR, SSZ-13, FER, and Y zeolite) catalysts are prepared with the improved impregnation method. The effects of reaction temperature and the composition of the reaction gas (ammonia, oxygen, and ethane) on the catalytic reaction are investigated. Adjusting the fraction of ammonia and/or ethane in the reaction gas can effectively strengthen the ethane dehydrogenation (ED) route and ethylamine dehydrogenation (EA) route and inhibit the ethylene peroxidation (EO) route, whereas the adjustment of oxygen cannot effectively promote acetonitrile formation because it cannot avoid enhancing the EO route. By comparing the acetonitrile yields on different Sn/H-zeolite catalysts at 600 °C, it is revealed that the ammonia pool effect, the residual Brönsted acid in the zeolite, and the Sn-Lewis acid synergistically catalyze ethane ammoxidation. Moreover, a higher L/B ratio of the Sn/H zeolite is beneficial to the improvement of acetonitrile yield. With a certain application potential, the Sn/H-FER-zeolite catalyst shows an ethane conversion of 35.2% and an acetonitrile yield of 22.9% at 600 °C; although a similar catalytic performance was observed on the best Co-zeolite catalyst in literature, the Sn/H-FER-zeolite catalyst is more selective to ethene and CO than the Co catalyst. In addition, the selectivity to CO2 is less than 2% of that on the Sn-zeolite catalyst. This may be attributed to the special 2D topology and pore/channel system of the FER zeolite, which guarantee an ideal synergistic effect of the ammonia pool, the residual Brönsted acid in the zeolite, and the Sn-Lewis acid for the Sn/H-FER-catalyzed ethane ammoxidation reaction.
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We have developed a method of introducing biological oxime ether fragments into peptides by CuI-catalyzed late-stage modification and functionalization of peptides, utilizing their acid moiety and varied 2H-azirines. As a result of its mild conditions, high atom economy, moderate yield, and excellent functional-group tolerance, the method can provide access to late-stage peptide modification and functionalization at their acid sites both in the homogeneous phase and on resins in SPPS, providing a new tool kit for peptide functionalization, diversification, and fluorescent labeling.
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Cobre , Éteres , Ácidos Carboxílicos , Oximas , Peptídeos , CatáliseRESUMO
Herein, we explored an unprecedented mild, nonirritating, conveniently available, and recyclable coupling reagent NDTP, which could activate the carboxylic acids via acyl thiocyanide and enable the rapid amide and peptide synthesis at very mild conditions. In addition, the methodology was compatible with Fmoc-SPPS, which may provide an alternative to peptide manufacturing.
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Amidas/síntese química , Peptídeos/síntese química , Amidas/química , Ácidos Carboxílicos/química , Estrutura Molecular , Peptídeos/química , Estereoisomerismo , Tiocianatos/químicaRESUMO
In this work, we report on the synthesis of InSe nanobelts through a catalyst-free chemical vapor deposition (CVD) growth approach. A remarkable blue shift of the peak photoresponse was observed when the thickness of the InSe nanobelt decreases from 562 to 165 nm. Silvaco Technology Computer Aided Design (TCAD) simulation reveals that such a shift in spectral response should be ascribed to the wavelength-dependent absorption coefficient of InSe, for which incident light with shorter wavelengths will be absorbed near the surface, while light with longer wavelengths will have a greater penetration depth, leading to a red shift of the absorption edge for thicker nanobelt devices. Considering the above theory, three kinds of photodetectors sensitive to blue (450 nm), green (530 nm), and red (660 nm) incident light were achieved by tailoring the thickness of the nanobelts, which can enable the spectral reconstruction of a purple "H" pattern, suggesting the potential application of 2D layered semiconductors in full-color imaging.
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Non-genetically modified somatic cells can only be inefficiently and stochastically reprogrammed to pluripotency by exogenous expression of reprogramming factors. Low competence of natural reprogramming factors may prevent the majority of cells to successfully and synchronously reprogram. Here we screened DNA-interacting amino acid residues in the zinc-finger domain of KLF4 for enhanced reprogramming efficiency using alanine-substitution scanning methods. Identified KLF4 L507A mutant accelerated and stabilized reprogramming to pluripotency in both mouse and human somatic cells. By testing all the variants of L507 position, variants with smaller amino acid residues in the KLF4 L507 position showed higher reprogramming efficiency. L507A bound more to promoters or enhancers of pluripotency genes, such as KLF5, and drove gene expression of these genes during reprogramming. Molecular dynamics simulations predicted that L507A formed additional interactions with DNA. Our study demonstrates how modifications in amino acid residues of DNA-binding domains enable next-generation reprogramming technology with engineered reprogramming factors.
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Adrenoleukodystrophy (ALD) is an X-linked genetic disorder, characterized by demyelination in the central nervous system and adrenal insufficiency. Human induced pluripotent stem cell (hiPSC) lines derived from two Japanese male patients with ALD were generated from skin fibroblasts using retroviral vectors. The generated hiPSC lines showed self-renewal and pluripotency, and carried either a missense or a nonsense mutation in ABCD1 gene. Since the molecular pathogenesis caused by ABCD1 dysfunction remains unclear, these cell resources provide useful tools to establish disease models and to develop new therapies for X-ALD.
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Adrenoleucodistrofia , Doenças Genéticas Ligadas ao Cromossomo X , Células-Tronco Pluripotentes Induzidas , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Adrenoleucodistrofia/genética , Fibroblastos , Humanos , Masculino , Mutação/genéticaRESUMO
Functional assessment is an essential part of rehabilitation protocols after stroke. Conventionally, the assessment process relies heavily on clinical experience and lacks quantitative analysis. In order to objectively quantify the upper-limb motor impairments in patients with post-stroke hemiparesis, this study proposes a novel assessment approach based on motor synergy quantification and multi-modality fusion. Fifteen post-stroke hemiparetic patients and fifteen age-matched healthy persons participated in this study. During different goal-directed tasks, kinematic data and surface electromyography(sEMG) signals were synchronously collected from these participants, and then motor features extracted from each modal data could be fed into the respective local classifiers. In addition, kinematic synergies and muscle synergies were quantified by principal component analysis (PCA) and k weighted angular similarity ( k WAS) algorithm to provide in-depth analysis of the coactivated features responsible for observable movement impairments. By integrating the outputs of local classifiers and the quantification results of motor synergies, ensemble classifiers can be created to generate quantitative assessment for different modalities separately. In order to further exploit the complementarity between the evaluation results at kinematic and muscular levels, a multi-modal fusion scheme was developed to comprehensively analyze the upper-limb motor function and generate a probability-based function score. Under the proposed assessment framework, three types of machine learning methods were employed to search the optimal performance of each classifier. Experimental results demonstrated that the classification accuracy was respectively improved by 4.86% and 2.78% when the analysis of kinematic and muscle synergies was embedded in the assessment system, and could be further enhanced to 96.06% by fusing the characteristics derived from different modalities. Furthermore, the assessment result of multi-modality fusion framework exhibited a significant correlation with the score of standard clinical tests ( R = - 0.87, P = 1.98e - 5 ). These promising results show the feasibility of applying the proposed method to clinical assessments for post-stroke hemiparetic patients.
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Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Fenômenos Biomecânicos , Humanos , Paresia/etiologia , Acidente Vascular Cerebral/complicações , Extremidade SuperiorRESUMO
Replacing expensive and thermally unstable growth factors with synthetic alternatives has been an important issue in stem cell-based regenerative medicines. Here we developed DNA aptamer-assemblies that act as functional mimics of basic fibroblast growth factor (bFGF), one of the essential factors for stem cell culture. The most potent aptamer assembly named TD0, composed solely of 76-mer single-stranded DNA, could support the self-renewal and pluripotency of induced pluripotent stem cells (iPSCs). This work presents the first application of DNA aptamer in the maintenance of iPSCs.
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Aptâmeros de Nucleotídeos/química , Materiais Biocompatíveis/química , Aptâmeros de Nucleotídeos/metabolismo , Aptâmeros de Nucleotídeos/farmacologia , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fatores de Crescimento de Fibroblastos/química , Fatores de Crescimento de Fibroblastos/farmacologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Fosforilação , Ligação Proteica , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/agonistas , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Regulação para Cima/genéticaRESUMO
The kinematic redundancy of human arm imposes challenges on joint space trajectory planning for upper-limb rehabilitation robot. This paper aims to investigate normal motion patterns in reaching and reach-to-grasp movements, and obtain the unique solution in joint space for a five-DOF exoskeleton. Firstly, a six-camera optical motion tracking system was used to capture participants' arm motion during goal-directed reaching or reach-to-grasp movements. Secondly, statistical analysis was executed to explore the characteristics of swivel angle, which revealed that the swivel angle can be approximated to the mean value (155° ± 5°) in resolving the arm redundancy problem. Thirdly, combined with the minimum-jerk trajectory of end-effector, the generated joint trajectory complied well with the joint trajectory captured in healthy humans. Consequently, the obtained results facilitate a new way for three-dimensional trajectory planning of the exoskeleton robot. Further, adaptive assist-as-needed control of the exoskeleton robot can be implemented based on the optimal reference trajectory, with aims to provide assistance according to the patient's performance, and in turn promote neural plasticity.
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Exoesqueleto Energizado , Robótica , Fenômenos Biomecânicos , Objetivos , Humanos , Movimento (Física) , Reabilitação/instrumentação , Extremidade SuperiorRESUMO
Various somatic stem cells divide asymmetrically; however, it is not known whether embryonic stem cells (ESCs) divide symmetrically or asymmetrically, not only while maintaining an undifferentiated state but also at the onset of differentiation. In this study, we observed single ESCs using time-lapse imaging and compared sister cell pairs derived from the same mother cell in either the maintenance or differentiation medium. Mouse ESCs were cultured on E-cadherin-coated glass-based dishes, which allowed us to trace single cells. The undifferentiated cell state was detected by green fluorescent protein (GFP) expression driven by the Nanog promoter, which is active only in undifferentiated cells. Cell population analysis using flow cytometry showed that the peak width indicating distribution of GFP expression broadened when cells were transferred to the differentiation medium compared to when they were in the maintenance medium. This finding suggested that the population of ESCs became more heterogeneous at the onset of differentiation. Using single-cell analysis by time-lapse imaging, we found that although the total survival ratio decreased by changing to differentiation medium, the one-live-one-dead ratio of sister cell pairs was smaller compared with randomly chosen non-sister cell pairs, defined as an unsynchronized cell pair control, in both media. This result suggested that sister cell pairs were more positively synchronized with each other compared to non-sister cell pairs. The differences in interdivision time (the time interval between mother cell division and the subsequent cell division) between sister cells was smaller than that between non-sister cell pairs in both media, suggesting that sister cells divided synchronously. Although the difference in Nanog-GFP intensity between sister cells was smaller than that between non-sister cells in the maintenance medium, it was the same in differentiation medium, suggesting asymmetrical Nanog-GFP intensity. These data suggested that ESCs may divide asymmetrically at the onset of differentiation resulting in heterogeneity.