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1.
Rinsho Ketsueki ; 60(9): 1046-1055, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31597826

RESUMO

Human iPS cells are somatic cells reprogrammed to the pluripotent state. Because of their pluripotent nature, iPS cells are now commonly used to model several developmental processes including hematopoiesis in vitro. The in vitro models can be used to study the mechanisms regulating not only normal hematopoiesis but also hematological diseases ranging from monogenic congenital disorders to genetically multifactorial malignancies. Those disease models can also be used to investigate novel treatments through procedures including high throughput drug screening. The possible clinical applications of iPS cell-derived hematopoietic cells include immunotherapy with T lymphocytes, NK cells and macrophages, and transfusion therapy with platelets and red blood cells. Platelets have now been produced from iPS cells in quantities sufficient for clinical use. By developing expandable immortalized megakaryocyte cell lines (imMKCLs), several novel drugs and turbulence-incorporated bioreactors, efficient and scalable generation of platelets was achieved. This review summarizes the current status of iPS cell research in hematopoiesis with details on iPS cell-derived platelets.


Assuntos
Plaquetas/citologia , Terapia Baseada em Transplante de Células e Tecidos , Células-Tronco Pluripotentes Induzidas/citologia , Diferenciação Celular , Eritrócitos , Hematopoese , Humanos , Imunoterapia , Células Matadoras Naturais , Macrófagos , Megacariócitos , Linfócitos T
2.
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
3.
Mol Biol (Mosk) ; 53(5): 725-740, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31661474

RESUMO

Human pluripotent stem cells, which include embryonic stem cells and induced pluripotent cells (iPSCs), are capable of unlimited division and differentiation into all cells of the body. These cells are considered as a potential source of various types of cells for transplantations. The use of autologous iPSCs is not potentially associated with immune rejection and does not require immunosuppression required for allogeneic grafts. However, the high cost of this technology and the duration of obtaining iPSCs and differentiated cells may limit the use of autologous iPSCs in clinical practice. In addition, full equivalence and immunological compatibility of autologous iPSCs and their derivatives have been repeatedly questioned. One approach to solving the problem of the immunological compatibility of allogeneic derivatives of iPSCs can be the establishment of cell lines with reduced immunogenicity. Differentiated derivatives of such iPSCs may be suitable for transplantation to any patient. This review discusses the strategies for evading immune surveillance in normal and tumor processes that can be used to establish stem cell lines with reduced immunogenicity.


Assuntos
Linhagem Celular/citologia , Linhagem Celular/imunologia , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/imunologia , Diferenciação Celular , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/imunologia , Humanos
4.
Adv Exp Med Biol ; 1186: 33-53, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31654385

RESUMO

The advent of stem cell technology, including the technology to induce pluripotency in somatic cells, and direct differentiation of stem cells into specific somatic cell types, has created an exciting new field of scientific research. Much of the work with pluripotent stem (PS) cells has been focused on the exploration and exploitation of their potential as cells/tissue replacement therapies for personalized medicine. However, PS and stem cell-derived somatic cells are also proving to be valuable tools to study disease pathology and tissue-specific responses to injury. High-throughput drug screening assays using tissue-specific injury models have the potential to identify specific and effective treatments that will promote wound healing. Retinal pigment epithelium (RPE) derived from induced pluripotent stem cells (iPS-RPE) are well characterized cells that exhibit the phenotype and functions of in vivo RPE. In addition to their role as a source of cells to replace damaged or diseased RPE, iPS-RPE provide a robust platform for in vitro drug screening to identify novel therapeutics to promote healing and repair of ocular tissues after injury. Proliferative vitreoretinopathy (PVR) is an abnormal wound healing process that occurs after retinal tears or detachments. In this chapter, the role of iPS-RPE in the development of an in vitro model of PVR is described. Comprehensive analyses of the iPS-RPE response to injury suggests that these cells provide a physiologically relevant tool to investigate the cellular mechanisms of the three phases of PVR pathology: migration, proliferation, and contraction. This in vitro model will provide valuable information regarding cellular wound healing responses specific to RPE and enable the identification of effective therapeutics.


Assuntos
Células-Tronco Pluripotentes Induzidas , Epitélio Pigmentado da Retina , Vitreorretinopatia Proliferativa , Diferenciação Celular , Células Cultivadas , Humanos , Técnicas In Vitro , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/patologia , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/patologia , Vitreorretinopatia Proliferativa/patologia
5.
Adv Exp Med Biol ; 1186: 171-193, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31654390

RESUMO

The success rate from investigational new drug filing to drug approval has remained low for decades despite major scientific and technological advances, and a steady increase of funding and investment. The failure to demonstrate drug efficacy has been the major reason that drug development does not progress beyond phase II and III clinical trials. The combination of two-dimensional (2D) cellular in vitro and animal models has been the gold standard for basic science research and preclinical drug development studies. However, most findings from these systems fail to translate into human trials because these models only partly recapitulate human physiology and pathology. The lack of a dynamic three-dimensional microenvironment in 2D cellular models reduces the physiological relevance, and for these reasons, 3D and microfluidic model systems are now being developed as more native-like biological assay platforms. 3D cellular in vitro systems, microfluidics, self-organized organoids, and 3D biofabrication are the most promising technologies to mimic human physiology because they provide mechanical cues and a 3D microenvironment to the multicellular components. With the advent of human-induced pluripotent stem cell (iPSC) technology, the 3D dynamic in vitro systems further enable extensive access to human-like tissue models. As increasingly complex 3D cellular systems are produced, the use of current visualization technologies is limited due to the thickness and opaqueness of 3D tissues. Tissue-clearing techniques improve light penetration deep into tissues by matching refractive indices among the 3D components. 3D segmentation enables quantitative measurements based on 3D tissue images. Using these state-of-the-art technologies, high-throughput screening (HTS) of thousands of drug compounds in 3D tissue models is slowly becoming a reality. In order to screen thousands of compounds, machine learning will need to be applied to help maximize outcomes from the use of cheminformatics and phenotypic approaches to drug screening. In this chapter, we discuss the current 3D ocular models recapitulating physiology and pathology of the back of the eye and further discuss visualization and quantification techniques that can be implemented for drug screening in ocular diseases.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Oftalmopatias , Modelos Biológicos , Organoides , Engenharia Tecidual , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Oftalmopatias/patologia , Oftalmopatias/terapia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Microfluídica
6.
Nature ; 574(7776): 112-116, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31554966

RESUMO

Organogenesis is a complex and interconnected process that is orchestrated by multiple boundary tissue interactions1-7. However, it remains unclear how individual, neighbouring components coordinate to establish an integral multi-organ structure. Here we report the continuous patterning and dynamic morphogenesis of hepatic, biliary and pancreatic structures, invaginating from a three-dimensional culture of human pluripotent stem cells. The boundary interactions between anterior and posterior gut spheroids differentiated from human pluripotent stem cells enables retinoic acid-dependent emergence of hepato-biliary-pancreatic organ domains specified at the foregut-midgut boundary organoids in the absence of extrinsic factors. Whereas transplant-derived tissues are dominated by midgut derivatives, long-term-cultured microdissected hepato-biliary-pancreatic organoids develop into segregated multi-organ anlages, which then recapitulate early morphogenetic events including the invagination and branching of three different and interconnected organ structures, reminiscent of tissues derived from mouse explanted foregut-midgut culture. Mis-segregation of multi-organ domains caused by a genetic mutation in HES1 abolishes the biliary specification potential in culture, as seen in vivo8,9. In sum, we demonstrate that the experimental multi-organ integrated model can be established by the juxtapositioning of foregut and midgut tissues, and potentially serves as a tractable, manipulatable and easily accessible model for the study of complex human endoderm organogenesis.


Assuntos
Sistema Biliar/embriologia , Intestinos/embriologia , Fígado/embriologia , Modelos Biológicos , Morfogênese , Pâncreas/embriologia , Animais , Sistema Biliar/citologia , Biomarcadores/análise , Biomarcadores/metabolismo , Padronização Corporal , Endoderma/citologia , Endoderma/embriologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Intestinos/citologia , Fígado/citologia , Masculino , Camundongos , Organoides/citologia , Organoides/embriologia , Pâncreas/citologia , Esferoides Celulares/citologia , Esferoides Celulares/metabolismo , Esferoides Celulares/transplante , Fatores de Transcrição HES-1/análise , Fatores de Transcrição HES-1/metabolismo
7.
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
8.
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.
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
10.
Cancer Sci ; 110(10): 3027-3037, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31348591

RESUMO

We previously established a method to generate myeloid cells with a proliferative capability from pluripotent stem cells and designated them iPS-ML. Human iPS-ML cells share features with physiological macrophages including the capability to infiltrate into cancer tissues. We observed therapeutic effects of human iPS-ML cells expressing interferon ß (iPS-ML/interferon (IFN)-ß) in xenograft cancer models. However, assessment of host immune system-mediated therapeutic and adverse effects of this therapy is impossible by xenograft models. We currently evaluated the therapeutic effects of a mouse equivalent of human iPS-ML/IFN, a mouse embryonic stem (ES) cell-derived myeloid cell line producing IFN (ES-ML/IFN). The ES-MLs producing IFN-ß (ß-ML) and IFN-γ (γ-ML) and originating from E14 ES cells derived from the 129 mouse strain (H-2b ) were generated, and the MHC (H-2Kb , Db , and I-Ab ) genes of the ES-ML/IFN were disrupted using the clustered regularly interspaced short palindromic repeats (CRISPR)/CAS9 method. We used the ES-ML/IFN to treat allogeneic BALB/c mice (H-2d ) transplanted with Colon26 cancer cells. Treatment with ß-ML but not with γ-ML cells repressed the growth of colon cancer in the peritoneal cavity and liver. The transferred ES-ML/IFN infiltrated into cancer tissues and enhanced infiltration of T cells into cancer tissues. ES-ML/IFN therapy increased the number of immune cells in the lymphoid organs. Sensitization of both cancer antigen-specific CD8+ T cells and natural killer (NK) cells were enhanced by the therapy, and CD8+ T cells were essential for the therapeutic effect, implying that donor MHC-deficient ß-ML exhibited a therapeutic effect through the activation of host immune cells derived from allogeneic recipient mice. The results suggested the usefulness of HLA-deficient human iPS-ML/IFN-ß cells for therapy of HLA-mismatched allogeneic cancer patients.


Assuntos
Neoplasias do Colo/terapia , Células-Tronco Embrionárias/citologia , Antígenos de Histocompatibilidade/genética , Interferon beta/metabolismo , Células Mieloides/transplante , Animais , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/imunologia , Células-Tronco Embrionárias/metabolismo , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células Matadoras Naturais/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células Mieloides/citologia , Células Mieloides/metabolismo , Transplante Homólogo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
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
12.
Cell Mol Life Sci ; 76(20): 3953-3967, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31250034

RESUMO

The brain tissue has only a limited capacity for generating new neurons. Therefore, to treat neurological diseases, there is a need of other cell sources for brain repair. Different sources of cells have been subject of intense research over the years, including cells from primary tissue, stem cell-derived cells and reprogrammed cells. As an alternative, direct reprogramming of resident brain cells into neurons is a recent approach that could provide an attractive method for treating brain injuries or diseases as it uses the patient's own cells for generating novel neurons inside the brain. In vivo reprogramming is still in its early stages but holds great promise as an option for cell therapy. To date, both inhibitory and excitatory neurons have been obtained via in vivo reprogramming, but the precise phenotype or functionality of these cells has not been analysed in detail in most of the studies. Recent data shows that in vivo reprogrammed neurons are able to functionally mature and integrate into the existing brain circuitry, and compose interneuron phenotypes that seem to correlate to their endogenous counterparts. Interneurons are of particular importance as they are essential in physiological brain function and when disturbed lead to several neurological disorders. In this review, we describe a comprehensive overview of the existing studies involving brain repair, including in vivo reprogramming, with a focus on interneurons, along with an overview on current efforts to generate interneurons for cell therapy for a number of neurological diseases.


Assuntos
Lesões Encefálicas/terapia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células-Tronco Pluripotentes Induzidas/citologia , Interneurônios/citologia , Doenças Neurodegenerativas/terapia , Regeneração/fisiologia , Animais , Biomarcadores/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Lesões Encefálicas/genética , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Transdiferenciação Celular , Reprogramação Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Injeções Intraventriculares , Interneurônios/metabolismo , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Neurogênese/genética , Transplante de Células-Tronco/métodos
13.
Int J Mol Sci ; 20(11)2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31146354

RESUMO

Modern diagnostic strategies for early recognition of cancer therapeutics-related cardiac dysfunction involve cardiac troponins measurement. Still, the role of other markers of cardiotoxicity is still unclear. The present study was designed to investigate dynamics of response of human cardiomyocytes derived from induced pluripotent stem cells (hiPCS-CMs) to doxorubicin with the special emphasis on their morphological changes in relation to expression and organization of troponins. The hiPCS-CMs were treated with doxorubicin concentrations (1 and 0.3 µM) for 48 h and followed for next up to 6 days. Exposure of hiPCS-CMs to 1 µM doxorubicininduced suppression of both cardiac troponin T (cTnT) and cardiac troponin I (cTnI) gene expression. Conversely, lower 0.3 µM doxorubicin concentration produced no significant changes in the expression of aforementioned genes. However, the intracellular topography, arrangement, and abundance of cardiac troponin proteins markedly changed after both doxorubicin concentrations. In particular, at 48 h of treatment, both cTnT and cTnI bundles started to reorganize, with some of them forming compacted shapes extending outwards and protruding outside the cells. At later intervals (72 h and onwards), the whole troponin network collapsed and became highly disorganized following, to some degree, overall changes in the cellular shape. Moreover, membrane permeability of cardiomyocytes was increased, and intracellular mitochondrial network rearranged and hypofunctional. Together, our results demonstrate complex effects of clinically relevant doxorubicin concentrations on hiPCS-CM cells including changes in cTnT and cTnI, but also in other cellular compartments contributing to the overall cytotoxicity of this class of cytostatics.


Assuntos
Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Troponina/metabolismo , Antineoplásicos/farmacologia , Cardiotoxicidade , Linhagem Celular , Doxorrubicina/farmacologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo
14.
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
15.
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
16.
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
17.
Cell Prolif ; 52(4): e12604, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31069891

RESUMO

OBJECTIVE: For optimized expansion of human-induced pluripotent stem cells (hiPSCs) with regards to clinical applications, we investigated the influence of the inoculum density on the expansion procedure in 3D hollow-fibre bioreactors. MATERIALS AND METHODS: Analytical-scale bioreactors with a cell compartment volume of 3 mL or a large-scale bioreactor with a cell compartment volume of 17 mL were used and inoculated with either 10 × 106 or 50 × 106 hiPSCs. Cells were cultured in bioreactors over 15 days; daily measurements of biochemical parameters were performed. At the end of the experiment, the CellTiter-Blue® Assay was used for culture activity evaluation and cell quantification. Also, cell compartment sections were removed for gene expression and immunohistochemistry analysis. RESULTS: The results revealed significantly higher values for cell metabolism, cell activity and cell yields when using the higher inoculation number, but also a more distinct differentiation. As large inoculation numbers require cost and time-extensive pre-expansion, low inoculation numbers may be used preferably for long-term expansion of hiPSCs. Expansion of hiPSCs in the large-scale bioreactor led to a successful production of 5.4 × 109 hiPSCs, thereby achieving sufficient cell amounts for clinical applications. CONCLUSIONS: In conclusion, the results show a significant effect of the inoculum density on cell expansion, differentiation and production of hiPSCs, emphasizing the importance of the inoculum density for downstream applications of hiPSCs. Furthermore, the bioreactor technology was successfully applied for controlled and scalable production of hiPSCs for clinical use.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Reatores Biológicos , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos
18.
Methods Mol Biol ; 1975: 363-405, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31062319

RESUMO

The notion of reprogramming cell fate is a direct challenge to the traditional view in developmental biology that a cell's phenotypic identity is sealed after undergoing differentiation. Direct experimental evidence, beginning with the somatic cell nuclear transfer experiments of the twentieth century and culminating in the more recent breakthroughs in transdifferentiation and induced pluripotent stem cell (iPSC) reprogramming, have rewritten the rules for what is possible with cell fate transformation. Research is ongoing in the manipulation of cell fate for basic research in disease modeling, drug discovery, and clinical therapeutics. In many of these cell fate reprogramming experiments, there is often little known about the genetic and molecular changes accompanying the reprogramming process. However, gene regulatory networks (GRNs) can in some cases be implicated in the switching of phenotypes, providing a starting point for understanding the dynamic changes that accompany a given cell fate reprogramming process. In this chapter, we present a framework for computationally analyzing cell fate changes by mathematically modeling these GRNs. We provide a user guide with several tutorials of a set of techniques from dynamical systems theory that can be used to probe the intrinsic properties of GRNs as well as study their responses to external perturbations.


Assuntos
Diferenciação Celular , Reprogramação Celular , Biologia Computacional/métodos , Redes Reguladoras de Genes , Células-Tronco Pluripotentes Induzidas/citologia , Linhagem da Célula , Simulação por Computador , Humanos , Modelos Teóricos
19.
Methods Mol Biol ; 1975: 427-454, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31062321

RESUMO

The field of cell fate engineering is contingent on tools that can quantitatively assess the efficacy of cell fate engineering protocols and experiments. CellNet is such a cell fate assessment tool that utilizes network biology to both evaluate and suggest candidate transcriptional regulatory modifications to improve the similarity of an engineered population to its corresponding in vivo target population. CellNet takes in expression profiles in the form of RNA-sequencing data and generates several metrics of cell identity and protocol efficacy. In this chapter, we demonstrate how to (1) preprocess raw RNA-sequencing data to generate an expression matrix, (2) train CellNet using preprocessed expression matrices, and (3) apply CellNet to a query study and interpret its results. We demonstrate the utility of CellNet for analysis of iPSC disease modeling studies, which we evaluate through the lens of cell fate engineering.


Assuntos
Engenharia Celular/métodos , Linhagem da Célula , Biologia Computacional/métodos , Doença/genética , Regulação da Expressão Gênica , Células-Tronco Pluripotentes Induzidas/citologia , Software , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia
20.
Neurochem Res ; 44(7): 1736-1744, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31037609

RESUMO

Recent advances in human induced pluripotent stem cells (hiPSCs) offer new possibilities for biomedical research and clinical applications. Neurons differentiated from hiPSCs may be promising tools to develop novel treatment methods for various neurological diseases. However, the detailed process underlying functional maturation of hiPSC-derived neurons remains poorly understood. Here, we analyze the developmental architecture of hiPSC-derived cortical neurons, iCell GlutaNeurons, focusing on the primary cilium, a single sensory organelle that protrudes from the surface of most growth-arrested vertebrate cells. To characterize the neuronal cilia, cells were cultured for various periods and evaluated immunohistochemically by co-staining with antibodies against ciliary markers Arl13b and MAP2. Primary cilia were detected in neurons within days, and their prevalence and length increased with increasing days in culture. Treatment with the mood stabilizer lithium led to primary cilia length elongation, while treatment with the orexigenic neuropeptide melanin-concentrating hormone caused cilia length shortening in iCell GlutaNeurons. The present findings suggest that iCell GlutaNeurons develop neuronal primary cilia together with the signaling machinery for regulation of cilia length. Our approach to the primary cilium as a cellular antenna can be useful for both assessment of neuronal maturation and validation of pharmaceutical agents in hiPSC-derived neurons.


Assuntos
Cílios/metabolismo , Cílios/ultraestrutura , Células-Tronco Pluripotentes Induzidas/citologia , Neurônios/citologia , Fatores de Ribosilação do ADP/imunologia , Adenilil Ciclases/imunologia , Animais , Anticorpos/imunologia , Linhagem Celular , Cílios/efeitos dos fármacos , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Humanos , Hormônios Hipotalâmicos/farmacologia , Imuno-Histoquímica , Lítio/farmacologia , Melaninas/farmacologia , Proteínas Associadas aos Microtúbulos/imunologia , Neurogênese/fisiologia , Neurônios/efeitos dos fármacos , Hormônios Hipofisários/farmacologia , Ratos Wistar , Receptores de Somatostatina/imunologia
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