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1.
Adv Exp Med Biol ; 1175: 383-405, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583596

RESUMO

Despite over a century of research into Alzheimer's disease (AD), progress in understanding the complex aetiology has been hindered, in part, by a lack of human, disease relevant, cellular models, reflected in an inability to translate results from animal studies to successful human therapies. Induced pluripotent stem cell (iPSC) technology, in which somatic cells are reprogrammed to pluripotent stem cells, creates an ideal physiologically relevant model as they maintain the genetic identity of the donor. These iPSCs can self-renew indefinitely in vitro and have the capacity to differentiate into any cell type, opening up new discovery and therapeutic opportunities. Despite a plethora of publications indicating the generation and utility of iPSC-derived neurones for disease modelling to date, in comparison only a limited number of studies have described generation of enriched astroglia from patients with early- or late-stage onset of AD. We recently reported that iPSC-astroglia derived from these patients are capable of mimicking a wide variety of deficits in homeostatic molecular cascades, intimately associated with AD, that are routinely observed in vivo. This review examines the opportunities and limitations of this innovative technology in the context of AD modelling and uses for preclinical discovery to improve our success for an efficacious therapeutic outcome.


Assuntos
Doença de Alzheimer , Astrócitos/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Animais , Humanos , Neurônios
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(4): 1253-1258, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418389

RESUMO

OBJECTIVE: To obtain induced pluripatent stem cells (iPSC) from peripheral blood mononucleated cells and further induce differentiation into mesenchymal stem cells (MSC), and to compare the biological characteristics of iPSC-derived MSC and other-derived MSC. METHODS: Peripheral blood mononucleated cells were obtained and transduced with reprogramming factors by sendai virus vector. Induced differentiation of MSC was performed in 1 strain of iPSC that completed all identification, and their cell morphology and immunophenotype were identified by immu-nohistochemistry and flow cytometry. Adipogenic and osteogenic media were used to induce the adipogenic and osteogenic differentiation. The expression of immune-related transcription factors was identified by PCR to systematically elucidate the biological characteristics of iPSC-induced MSC. RESULTS: After transfection with sendai virus with reprogramming factor, the fate of peripheral blood mononucleated cells was reversed, initiating the expression of stem cell characteristics, the iPSC was successfully cloned, amplified, and purified, and finally the stable proliferation of iPSC was obtained. Mesenchymal stem cells derived from iPSC, had morphology consistent with other-derived MSC, and the immunophenotypes met the standard. iPSC-MSC possessed the ability of lipogenic and osteogenic differentiation. RT-PCR showed that iPSC-MSC was high expression to PDL1, and low expression to A20; besides, the expression level of STAT3 was equal to BM-MSC; and also as to the expression level of HIF1α and UC-MSC, which was lower than BM-MSC. CONCLUSION: Peripheral blood mononucleated cells successfully initiated the expression of stem cell characteristics after the transduction of sendai virus vector with reprogramming factors, and obtained multi-competent iPSC. iPSC can successfully be induced to the differentiation of MSC, and the iPSC-MSC have standard cell morphology, immunophenotype and differentiation ability. High expression of PDL1 and low expression of A20 in iPSC-MSC suggest that iPSC-derived cells have different biological characteristics in cell proliferation and immune regulation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Mesenquimais , Adipogenia , Diferenciação Celular , Humanos , Osteogênese
3.
Nihon Yakurigaku Zasshi ; 154(2): 72-77, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31406046

RESUMO

In drug disposition, the liver and small intestine are very important as tissues involving in drug metabolism, absorption, and excretion. Thus, in drug development studies, it is necessary to evaluate the pharmacokinetics in these tissues accurately including the contributions of drug-metabolizing enzymes and drug transporters. Currently, all kinds of evaluation systems have been used for the pharmacokinetic prediction; however, there are some issues in these systems. Therefore, the researches for the development of human induced pluripotent stem (iPS) cell-derived hepatocytes and enterocytes, as novel systems besides existing ones, are being advanced. Because human iPS cells have abilities of pluripotency and almost infinite proliferation, it is thought to be possible to stably provide the high-quality cells that have similar characteristics to human normal tissue cells by using human iPS cells. In this review, we describe current status of differentiation studies of human iPS cell-derived hepatocytes and enterocytes and the functional characteristics of these cells centered on pharmacokinetic functions.


Assuntos
Enterócitos/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Diferenciação Celular , Avaliação Pré-Clínica de Medicamentos , Enterócitos/citologia , Hepatócitos/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Intestino Delgado , Fígado , Farmacocinética
4.
J Cell Biol ; 218(9): 2826-2828, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31427369

RESUMO

Lamins A and C are intermediate filaments that provide structural support to the nuclear envelope and regulate gene expression. In this issue, Bertero et al. (2019. J. Cell Biol. https://doi.org/10.1083/jcb.201902117) report that although lamin A/C haploinsufficient cardiomyocytes show disease-associated phenotypes, those changes cannot be explained by alterations in chromatin compartmentalization.


Assuntos
Cromatina , Células-Tronco Pluripotentes Induzidas , Haploinsuficiência , Lamina Tipo A/genética , Membrana Nuclear
5.
Biomater Sci ; 7(9): 3906-3917, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31322163

RESUMO

Cardiovascular diseases represent a major socio-economic burden. In recent years, considerable effort has been invested in optimizing cell delivery strategies to advance cell transplantation therapies to restore heart function for example after an infarct. A particular issue is that the implantation of cells using a non-electroconductive matrix potentially causes arrhythmia. Here, we demonstrate that our hydrazide-functionalized nanotubes-pericardial matrix-derived electroconductive biohybrid hydrogel provides a suitable environment for maturation of human-induced pluripotent stem cell (hiPSC)-derived cardiomyocytes. hiPSC-derived cardiomyocytes exhibited an improved contraction amplitude (>500%) on conductive hydrogels compared to cells cultured on Matrigel®. This was accompanied by increased cellular alignment, enhanced connexin 43 expression, and improved sarcomere organization suggesting maturation of the hiPSC-derived cardiomyocytes. Sarcomeric length of these cells increased from 1.3 to 1.7 µm. Moreover, 3D cell-laden engineered tissues exhibited enhanced calcium handling as well as positive response to external electrical and pharmaceutical stimulation. Collectively, our data indicate that our biohybrid hydrogels consisting of solubilized nanostructured pericardial matrix and electroconductive positively charged hydrazide-conjugated carbon nanotubes provide a promising material for stem cell-based cardiac tissue engineering.


Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Nanotubos de Carbono/química , Pericárdio/química , Tecidos Suporte/química , Biomarcadores/metabolismo , Cálcio/metabolismo , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Colágeno/química , Conexina 43/metabolismo , Combinação de Medicamentos , Condutividade Elétrica , Humanos , Laminina/química , Células-Tronco Mesenquimais/citologia , Tamanho da Partícula , Proteoglicanas/química
6.
Brain Nerve ; 71(8): 875-883, 2019 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-31346144

RESUMO

Parkinson's disease (PD), a common neurodegenerative disorder, is characterized by selective degeneration of dopaminergic neurons in the substantia nigra. There is no effective treatment to delay or halt the progression of PD. The establishment of disease models, based on human biology, is therefore important for developing effective disease-modifying therapies. The recent progress of human induced pluripotent stem cell-associated technologies provides an opportunity to understand disease etiology, discover new drugs, and develop novel therapeutic interventions.


Assuntos
Células-Tronco Pluripotentes Induzidas , Doença de Parkinson/patologia , Neurônios Dopaminérgicos/patologia , Humanos , Modelos Biológicos , Substância Negra/patologia
7.
Artigo em Chinês | MEDLINE | ID: mdl-31327193

RESUMO

Objective:The purpose of the present study was to explore the characteristics and differentiation of somatic cells in vitro undergoing a low pH treatment, so as to provide new therapeutic strategies for treating sensorineural hearing loss.Method: The human mature somatic cells were selected as the target cells, and the cells were treated with different pH values to observe the cell morphology. The cell characteristics were identified from alkaline phosphatase (AKP) activity, immunohistochemical staining and molecular biology, and the most suitable pH value was selected. In addition, a mouse model of the cochlear lesion was constructed using bilirubin. Subsequently, the characteristics and therapeutic effect of somatic cells undergoing low pH treatment were examined by morphology, AKP activity, immunofluorescence assay and Q-PCR.Result:The cell growth of the experimental group was significantly better than those in the control group. The activity of AKP in the experimental group was higher than that in the control group. The expression of Nanog and Oct4 was both positive in the two groups. When the cells were changed to neurobasol medium, the marker of Nestin was positive.Conclusion:The human somatic cells undergoing a low pH treatment showed the similar characteristics as those of induced pluripotent stem (iPS) cells; although the functions and therapeutic effect of these altered human somatic cells need to be further studied.


Assuntos
Ácidos/farmacologia , Diferenciação Celular , Células Cultivadas/citologia , Células Cultivadas/efeitos dos fármacos , Animais , Humanos , Concentração de Íons de Hidrogênio , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Camundongos
9.
Stud Health Technol Inform ; 261: 274-279, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31156129

RESUMO

The main goal of this research is to design, develop and implement an efficient protocol to generate 3D neural cultures derived from human induced Pluripotent Stem Cells (hiPSCs) coupled to Micro Electrode Arrays (MEA) in order to obtain an engineered and controlled brain-on-a-chip model. The use of patient specific iPSCs may offer novel insights into the pathophysiology of a large variety of disorders, including numerous neurodevelopmental and late-onset neurodegenerative conditions. With these in vitro patient specific models, we may have the possibility to test drugs and find ad hoc therapies in the direction of precision medicine.


Assuntos
Encéfalo , Células-Tronco Pluripotentes Induzidas , Dispositivos Lab-On-A-Chip , Técnicas de Cultura de Órgãos , Encéfalo/fisiologia , Humanos , Doenças Neurodegenerativas , Transtornos do Neurodesenvolvimento , Organoides
10.
Nat Commun ; 10(1): 2880, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253799

RESUMO

Cell state-specific promoters constitute essential tools for basic research and biotechnology because they activate gene expression only under certain biological conditions. Synthetic Promoters with Enhanced Cell-State Specificity (SPECS) can be superior to native ones, but the design of such promoters is challenging and frequently requires gene regulation or transcriptome knowledge that is not readily available. Here, to overcome this challenge, we use a next-generation sequencing approach combined with machine learning to screen a synthetic promoter library with 6107 designs for high-performance SPECS for potentially any cell state. We demonstrate the identification of multiple SPECS that exhibit distinct spatiotemporal activity during the programmed differentiation of induced pluripotent stem cells (iPSCs), as well as SPECS for breast cancer and glioblastoma stem-like cells. We anticipate that this approach could be used to create SPECS for gene therapies that are activated in specific cell states, as well as to study natural transcriptional regulatory networks.


Assuntos
Aprendizado de Máquina , Regiões Promotoras Genéticas , Software , Neoplasias da Mama , Linhagem Celular Tumoral , Separação Celular/métodos , Feminino , Regulação da Expressão Gênica , Biblioteca Gênica , Glioblastoma , Humanos , Células-Tronco Pluripotentes Induzidas , Lentivirus , Células-Tronco Neoplásicas , Organoides , Elementos Reguladores de Transcrição
11.
Cell Physiol Biochem ; 53(1): 36-48, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31169990

RESUMO

BACKGROUND/AIMS: Ivabradine lowers the heart rate by inhibition of hyperpolarisation-activated cyclic nucleotide-gated (HCN) channels mediating the 'funny' pacemaker current If in the sinoatrial node. It is clinically approved for the treatment of heart failure and angina pectoris. Due to its proposed high selectivity for If administration of ivabradine is not associated with the side effects commonly observed following the application of other heart rate lowering agents. Recent evidence, however, has shown significant affinity of ivabradine towards Kv11.1 (ether-a-go-go related gene, ERG) potassium channels. Despite the inhibition of Kv11.1 channels by ivabradine, cardiac action potential (AP) duration and heart rate corrected QT interval (QTc) of the human electrocardiogram (ECG) were not prolonged. We thus surmised that compensatory mechanisms might counteract the drug's inhibitory action on Kv11.1. METHODS: The effects of ivabradine on human Kv11.1 and Kv7.1 potassium, Cav1.2 calcium, and Nav1.5 sodium channels, heterologously expressed in tsA-201 cells, were studied in the voltage-clamp mode of the whole cell patch clamp technique. In addition, changes in action potential parameters of human induced pluripotent stem cell (iPSC) derived cardiomyocytes upon application of ivabradine were studied with current-clamp experiments. RESULTS: Here we show that ivabradine exhibits significant affinity towards cardiac ion channels other than HCN. We demonstrate for the first time inhibition of human voltage-gated Nav1.5 sodium channels at therapeutically relevant concentrations. Within this study we also confirm recent findings of human Kv11.1 inhibition by low µM concentrations of ivabradine and observed no prolongation of ventricular-like APs in cardiomyocytes derived from iPSCs. CONCLUSION: Our results provide an explanation why ivabradine, despite its affinity for Kv11.1 channels, does not prolong the cardiac AP and QTc interval. Furthermore, our results suggest the inhibition of voltage-gated Nav1.5 sodium channels to underlie the recent observations of slowed atrioventricular conduction by increased atrial-His bundle intervals upon administration of ivabradine.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Fármacos Cardiovasculares/farmacologia , Canais Iônicos/metabolismo , Ivabradina/farmacologia , Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo L/metabolismo , Linhagem Celular , Canal de Potássio ERG1/antagonistas & inibidores , Canal de Potássio ERG1/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Canais Iônicos/antagonistas & inibidores , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.5/química , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Técnicas de Patch-Clamp
12.
Nat Cell Biol ; 21(6): 687-699, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160711

RESUMO

We recently derived mouse expanded potential stem cells (EPSCs) from individual blastomeres by inhibiting the critical molecular pathways that predispose their differentiation. EPSCs had enriched molecular signatures of blastomeres and possessed developmental potency for all embryonic and extra-embryonic cell lineages. Here, we report the derivation of porcine EPSCs, which express key pluripotency genes, are genetically stable, permit genome editing, differentiate to derivatives of the three germ layers in chimeras and produce primordial germ cell-like cells in vitro. Under similar conditions, human embryonic stem cells and induced pluripotent stem cells can be converted, or somatic cells directly reprogrammed, to EPSCs that display the molecular and functional attributes reminiscent of porcine EPSCs. Importantly, trophoblast stem-cell-like cells can be generated from both human and porcine EPSCs. Our pathway-inhibition paradigm thus opens an avenue for generating mammalian pluripotent stem cells, and EPSCs present a unique cellular platform for translational research in biotechnology and regenerative medicine.


Assuntos
Diferenciação Celular/genética , Reprogramação Celular/genética , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes/citologia , Animais , Blastômeros/citologia , Blastômeros/metabolismo , Linhagem da Célula/genética , Células-Tronco Embrionárias/citologia , Camadas Germinativas/crescimento & desenvolvimento , Camadas Germinativas/metabolismo , Humanos , Camundongos , Medicina Regenerativa , Transdução de Sinais/genética , Suínos , Trofoblastos/citologia , Trofoblastos/metabolismo
13.
Biochemistry (Mosc) ; 84(3): 283-290, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31221066

RESUMO

Reprogramming of somatic cells is associated with overcoming the established epigenetic barrier. Key events in this process are changes in the DNA methylation landscape and histone modifications. Studying the factors affecting epigenetic plasticity will allow not only to reveal the principles underlying cell reprogramming but also to find possible ways to influence this process. Kaiso transcription factor is one of the protein interpreters of methylated DNA. By binding to methylated DNA, Kaiso attracts corepressor complexes affecting chromatin structure. In this work, we showed that the Kaiso gene knockout contributes to more efficient somatic reprogramming by affecting both cell proliferation and DNA methylation. The proposed mechanisms for the increase in the efficiency of somatic reprogramming associated with the Kaiso gene knockout is a decrease in the methylation level of the Oct4 promoter region in mouse embryonic fibroblasts before reprogramming.


Assuntos
Reprogramação Celular , Técnicas de Inativação de Genes , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Transcrição/metabolismo
14.
Biochemistry (Mosc) ; 84(3): 291-298, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31221067

RESUMO

Generation of patient-specific induced pluripotent stem cells (iPSCs) and their subsequent differentiation into cardiomyocytes opened new opportunities for studying pathogenesis of inherited cardiovascular diseases. One of these diseases is hypertrophic cardiomyopathy (HCM) for which no efficient therapy methods have been developed so far. In this study, the approach based on patient-specific iPSCs was applied to create a model of the disease. Genetic analysis of a hypertrophic cardiomyopathy patient revealed R326Q mutation in the MYBPC3 gene. iPSCs of the patient were generated and characterized. The cells were differentiated into cardiomyocytes together with the control iPSCs from a healthy donor. The patient's iPSC-derived cardiomyocytes exhibited early HCM features, such as abnormal calcium handling and increased intracellular calcium concentration. Therefore, cardiomyocytes obtained by directed differentiation of iPSCs from the HCM patient can be used as a model system to study HCM pathogenesis.


Assuntos
Cardiomiopatia Hipertrófica/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Modelos Biológicos , Adulto , Cálcio/metabolismo , Cardiomiopatia Hipertrófica/diagnóstico , Cardiomiopatia Hipertrófica/genética , Diferenciação Celular , Células Cultivadas , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Masculino
15.
Biochemistry (Mosc) ; 84(3): 299-309, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31221068

RESUMO

Patient-specific induced pluripotent stem cells (iPSCs) capable of differentiation into required cell type are a promising model for studying various pathological processes and development of new therapeutic approaches. However, no conventional strategies for using iPSCs in disease research have been established yet. Genetically encoded biosensors can be used for monitoring messenger molecules, metabolites, and enzyme activity in real time with the following conversion of the registered signals in quantitative data, thus allowing evaluation of the impact of certain molecules on pathology development. In this article, we describe the development of a universal cell-based platform for studying pathological processes associated with amyotrophic lateral sclerosis. For this purpose, we have created a series of plasmid constructs for monitoring endoplasmic reticulum stress, oxidative stress, apoptosis, and Ca2+-dependent hyperexcitability and generated transgenic iPSC line carrying mutation in the superoxide dismutase 1 gene (SOD1) and healthy control cell line. Both cell lines have specific transactivator sequence required for doxycycline-controlled transcriptional activation and can be used for a single-step biosensor insertion.


Assuntos
Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/patologia , Técnicas Biossensoriais/métodos , Células-Tronco Pluripotentes Induzidas/metabolismo , Apoptose , Cálcio/metabolismo , Diferenciação Celular , Células Cultivadas , Estresse do Retículo Endoplasmático , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Mutação , Estresse Oxidativo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
16.
Biochemistry (Mosc) ; 84(3): 310-320, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31221069

RESUMO

Ionotropic glutamate and GABA receptors regulate the differentiation and determine the functional properties of mature neurons. Both insufficient and excessive activity of these neurotransmission systems are associated with various nervous system diseases. Our knowledge regarding the expression profiles of these receptors and the mechanisms of their regulation during the differentiation of specialized human neuron subtypes is limited. Here the expression profiles of the NMDA and GABAA receptor subunits were explored during in vitro differentiation of human induced pluripotent stem cells (iPSCs) into ventral mesencephalic neurons. The correlation between the neuronal maturation and the expression dynamics of these genes was investigated, and the functional activity of these receptors was assessed by calcium imaging. The role of NMDA and GABAA receptors in neurite outgrowth and the development of spontaneous activity was analyzed using the viral transduction of neural progenitors with the reporter genes TagGFP and TagRFP. The data indicate that agonists of the investigated receptors can be employed for optimization of existing protocols for neural differentiation of iPSCs, in particular for acceleration of neuronal maturation.


Assuntos
Células-Tronco Pluripotentes Induzidas/metabolismo , Mesencéfalo/metabolismo , Neurônios/metabolismo , Receptores de GABA-A/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Diferenciação Celular , Células Cultivadas , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Mesencéfalo/citologia , Neurônios/citologia , Receptores de GABA-A/genética , Receptores de N-Metil-D-Aspartato/genética
17.
Semin Ophthalmol ; 34(4): 287-292, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31188052

RESUMO

Stem cells provide a promising new therapeutic approach for the treatment of multiple acquired and inherited retinal conditions. While to date, there have been numerous clinical trials examining the ability of stem cells to treat the geographic atrophy found in advanced non-neovascular age-related macular degeneration, fewer clinical trials have specifically examined stem-cell therapy for inherited retinal disease. Moreover, it remains to be seen if human stem cells will be able to regenerate the lost retinal cell populations that represent a final common pathway for most of the inherited retinal diseases, or if stem cells will secrete a neuroprotective paracrine factor that will delay progression of these diseases. Here, we will review a number of the current clinical trials, either completed or in process, that have been designed to specifically treat inherited retinal conditions. There was considerable initial concern that using human stem cells as therapeutic agents might have the potential to form benign tumors or trigger an immune response that would have deleterious effects on the patient's retina. Currently, the majority of the clinical trials reviewed share the conclusion that intraocular stem-cell approach is generally well tolerated and safe for patients. While there are some efficacy data that have been published for a few of the reviewed trials, none of the completed studies have been empowered to demonstrate statistically significant efficacy in humans.


Assuntos
Degeneração Retiniana/terapia , Transplante de Células-Tronco/métodos , Ensaios Clínicos como Assunto , Células-Tronco Embrionárias/transplante , Humanos , Células-Tronco Pluripotentes Induzidas/transplante
18.
Nat Commun ; 10(1): 2238, 2019 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31110246

RESUMO

Cardiac fibroblasts (CFs) play critical roles in heart development, homeostasis, and disease. The limited availability of human CFs from native heart impedes investigations of CF biology and their role in disease. Human pluripotent stem cells (hPSCs) provide a highly renewable and genetically defined cell source, but efficient methods to generate CFs from hPSCs have not been described. Here, we show differentiation of hPSCs using sequential modulation of Wnt and FGF signaling to generate second heart field progenitors that efficiently give rise to hPSC-CFs. The hPSC-CFs resemble native heart CFs in cell morphology, proliferation, gene expression, fibroblast marker expression, production of extracellular matrix and myofibroblast transformation induced by TGFß1 and angiotensin II. Furthermore, hPSC-CFs exhibit a more embryonic phenotype when compared to fetal and adult primary human CFs. Co-culture of hPSC-CFs with hPSC-derived cardiomyocytes distinctly alters the electrophysiological properties of the cardiomyocytes compared to co-culture with dermal fibroblasts. The hPSC-CFs provide a powerful cell source for research, drug discovery, precision medicine, and therapeutic applications in cardiac regeneration.


Assuntos
Diferenciação Celular , Fibroblastos/fisiologia , Coração/crescimento & desenvolvimento , Células-Tronco Pluripotentes Induzidas/fisiologia , Miocárdio/citologia , Linhagem Celular , Técnicas de Cocultura/métodos , Derme/citologia , Voluntários Saudáveis , Humanos , Microscopia Intravital , Microscopia de Fluorescência , Cultura Primária de Células
19.
Nat Commun ; 10(1): 2212, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101808

RESUMO

In mammalian cells, double-stranded DNA breaks (DSBs) are preferentially repaired through end-joining processes that generally lead to mixtures of insertions and deletions (indels) or other rearrangements at the cleavage site. In the presence of homologous DNA, homology-directed repair (HDR) can generate specific mutations, albeit typically with modest efficiency and a low ratio of HDR products:indels. Here, we develop hRad51 mutants fused to Cas9(D10A) nickase (RDN) that mediate HDR while minimizing indels. We use RDN to install disease-associated point mutations in HEK293T cells with comparable or better efficiency than Cas9 nuclease and a 2.7-to-53-fold higher ratio of desired HDR product:undesired byproducts. Across five different human cell types, RDN variants generally result in higher HDR:indel ratios and lower off-target activity than Cas9 nuclease, although HDR efficiencies remain strongly site- and cell type-dependent. RDN variants provide precision editing options in cell types amenable to HDR, especially when byproducts of DSBs must be minimized.


Assuntos
Proteína 9 Associada à CRISPR/metabolismo , Engenharia Genética/métodos , Rad51 Recombinase/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Reparo de DNA por Recombinação , Proteína 9 Associada à CRISPR/genética , Quebras de DNA de Cadeia Dupla , Edição de Genes/métodos , Células HEK293 , Células HeLa , Humanos , Células-Tronco Pluripotentes Induzidas , Células K562 , Rad51 Recombinase/genética , Proteínas Recombinantes de Fusão/genética , Transfecção/métodos
20.
Nat Genet ; 51(6): 999-1010, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31110351

RESUMO

Human embryonic stem cells (ESCs) and human induced pluripotent stem cells hold great promise for cell-based therapies and drug discovery. However, homogeneous differentiation remains a major challenge, highlighting the need for understanding developmental mechanisms. We performed genome-scale CRISPR screens to uncover regulators of definitive endoderm (DE) differentiation, which unexpectedly uncovered five Jun N-terminal kinase (JNK)-JUN family genes as key barriers of DE differentiation. The JNK-JUN pathway does not act through directly inhibiting the DE enhancers. Instead, JUN co-occupies ESC enhancers with OCT4, NANOG, SMAD2 and SMAD3, and specifically inhibits the exit from the pluripotent state by impeding the decommissioning of ESC enhancers and inhibiting the reconfiguration of SMAD2 and SMAD3 chromatin binding from ESC to DE enhancers. Therefore, the JNK-JUN pathway safeguards pluripotency from precocious DE differentiation. Direct pharmacological inhibition of JNK significantly improves the efficiencies of generating DE and DE-derived pancreatic and lung progenitor cells, highlighting the potential of harnessing the knowledge from developmental studies for regenerative medicine.


Assuntos
Diferenciação Celular/genética , Endoderma/embriologia , Endoderma/metabolismo , Genoma , Genômica , Sistema de Sinalização das MAP Quinases , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Linhagem Celular , Cromatina/genética , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Expressão Gênica , Técnicas de Inativação de Genes , Genes Reporter , Genômica/métodos , Humanos , Células-Tronco Pluripotentes Induzidas , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Modelos Biológicos , Reprodutibilidade dos Testes , Proteínas Smad
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