Hereditary retinal dystrophies, specifically retinitis pigmentosa (RP) are clinically and genetically heterogeneous diseases affecting primarily retinal cells and retinal pigment epithelial cells with blindness as a final outcome. Understanding the pathogenicity behind these diseases has been largely precluded by the unavailability of affected tissue from patients, large genetic heterogeneity and animal models that do not faithfully represent some human diseases. A landmark discovery of human induced pluripotent stem cells (hiPSCs) permitted the derivation of patient-specific cells. These cells have unlimited self-renewing capacity and the ability to differentiate into RP-affected cell types, allowing the studies of disease mechanism, drug discovery, and cell replacement therapies, both as individual cell types and organoid cultures. Together with precise genome editing, the patient specific hiPSC technology offers novel strategies for targeting the pathogenic mutations and design therapies toward retinal dystrophies. This study summarizes current hiPSC-based RP models and highlights key achievements and challenges of these cellular models, as well as questions that still remain unanswered. Stem Cells 2018;36:474-481.

• MeSH
• autologní štěp MeSH
• buněčná diferenciace * MeSH
• editace genu * MeSH
• genom lidský * MeSH
• indukované pluripotentní kmenové buňky metabolismus   patologie   MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• retinopathia pigmentosa * genetika   metabolismus   patologie   terapie   MeSH
• transplantace kmenových buněk * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

The genomic destabilization associated with the adaptation of human embryonic stem cells (hESCs) to culture conditions or the reprogramming of induced pluripotent stem cells (iPSCs) increases the risk of tumorigenesis upon the clinical use of these cells and decreases their value as a model for cell biology studies. Base excision repair (BER), a major genomic integrity maintenance mechanism, has been shown to fail during hESC adaptation. Here, we show that the increase in the mutation frequency (MF) caused by the inhibition of BER was similar to that caused by the hESC adaptation process. The increase in MF reflected the failure of DNA maintenance mechanisms and the subsequent increase in MF rather than being due solely to the accumulation of mutants over a prolonged period, as was previously suggested. The increase in the ionizing-radiation-induced MF in adapted hESCs exceeded the induced MF in nonadapted hESCs and differentiated cells. Unlike hESCs, the overall DNA maintenance in iPSCs, which was reflected by the MF, was similar to that in differentiated cells regardless of the time spent in culture and despite the upregulation of several genes responsible for genome maintenance during the reprogramming process. Taken together, our results suggest that the changes in BER activity during the long-term cultivation of hESCs increase the mutagenic burden, whereas neither reprogramming nor long-term propagation in culture changes the MF in iPSCs.

• MeSH
• buněčná diferenciace účinky záření   MeSH
• buněčné linie MeSH
• genetické lokusy * MeSH
• hypoxanthinfosforibosyltransferasa genetika   metabolismus   MeSH
• indukované pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• lidé MeSH
• mutační rychlost * MeSH
• záření gama MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Induced pluripotent stem (iPS) cells are derived from differentiated cells by different reprogramming techniques, by introducing specific transcription factors responsible for pluripotency. Induced pluripotent stem cells can serve as an excellent source for differentiated neural stem/progenitor cells (NSCs/NPs). Several methods and protocols are utilized to create a robust number of NSCs/NPs without jeopardizing the safety issues required for in vivo applications. A variety of disease-specific iPS cells have been used to study nervous system diseases. In this chapter, we will focus on some of the derivation and differentiation approaches and the application of iPS-NPs in the treatment of spinal cord injury and stroke.

• MeSH
• buněčná diferenciace * MeSH
• cévní mozková příhoda patologie   terapie   MeSH
• indukované pluripotentní kmenové buňky cytologie   MeSH
• lidé MeSH
• modely neurologické * MeSH
• nervové kmenové buňky cytologie   MeSH
• poranění míchy patologie   terapie   MeSH
• přeprogramování buněk MeSH
• transkripční faktory metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

New approaches in regenerative medicine and vasculogenesis have generated a demand for sufficient numbers of human endothelial cells (ECs). ECs and their progenitors reside on the interior surface of blood and lymphatic vessels or circulate in peripheral blood; however, their numbers are limited, and they are difficult to expand after isolation. Recent advances in human induced pluripotent stem cell (hiPSC) research have opened possible avenues to generate unlimited numbers of ECs from easily accessible cell sources, such as the peripheral blood. In this study, we reprogrammed peripheral blood mononuclear cells, human umbilical vein endothelial cells (HUVECs), and human saphenous vein endothelial cells (HSVECs) into hiPSCs and differentiated them into ECs. The phenotype profiles, functionality, and genome stability of all hiPSC-derived ECs were assessed and compared with HUVECs and HSVECs. hiPSC-derived ECs resembled their natural EC counterparts, as shown by the expression of the endothelial surface markers CD31 and CD144 and the results of the functional analysis. Higher expression of endothelial progenitor markers CD34 and kinase insert domain receptor (KDR) was measured in hiPSC-derived ECs. An analysis of phosphorylated histone H2AX (γH2AX) foci revealed that an increased number of DNA double-strand breaks upon reprogramming into pluripotent cells. However, differentiation into ECs restored a normal number of γH2AX foci. Our hiPSCs retained a normal karyotype, with the exception of the HSVEC-derived hiPSC line, which displayed mosaicism due to a gain of chromosome 1. Peripheral blood from adult donors is a suitable source for the unlimited production of patient-specific ECs through the hiPSC interstage. hiPSC-derived ECs are fully functional and comparable to natural ECs. The protocol is eligible for clinical applications in regenerative medicine, if the genomic stability of the pluripotent cell stage is closely monitored.

• MeSH
• biologické markery metabolismus   MeSH
• buněčná diferenciace fyziologie   MeSH
• endoteliální buňky pupečníkové žíly (lidské) cytologie   metabolismus   MeSH
• endoteliální buňky cytologie   metabolismus   MeSH
• fibroblasty cytologie   metabolismus   MeSH
• fyziologická neovaskularizace fyziologie   MeSH
• indukované pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• kultivované buňky MeSH
• leukocyty mononukleární cytologie   metabolismus   MeSH
• lidé MeSH
• regenerativní lékařství metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Preclinical studies have demonstrated the promising potential of human induced pluripotent stem cells (hiPSCs) for clinical application. To fulfil this goal, efficient and safe methods to generate them must be established. Various reprogramming techniques were presented during seven years of hiPSCs research. Genome non-integrating and completely xeno-free protocols from the first biopsy to stable hiPSC clones are highly preferable in terms of future clinical application. In this short communication, we summarize the reprogramming experiments performed in our laboratories. We successfully generated hiPSCs using STEMCCA lentivirus, Sendai virus or episomal vectors. Human neonatal fibroblasts and CD34(+) blood progenitors were used as cell sources and were maintained either on mouse embryonic feeder cells or in feeder-free conditions. The reprogramming efficiency was comparable for all three methods and both cell types, while the best results were obtained in feeder-free conditions.

• MeSH
• antigeny CD34 metabolismus   MeSH
• biologické markery metabolismus   MeSH
• buněčné kultury metody   MeSH
• buněčné linie MeSH
• genom lidský genetika   MeSH
• imunohistochemie MeSH
• indukované pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• lidé MeSH
• myši MeSH
• pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• přeprogramování buněk genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Ectopic expression of defined sets of genetic factors can reprogramme somatic cells to induced pluripotent stem cells (iPSCs) that closely resemble embryonic stem cells. However, the low reprogramming efficiency is a significant handicap for mechanistic studies and potential clinical application. In this study, we used human bone marrow-derived mesenchymal stem cells (hBMMSCs) as target cells for reprogramming and investigated efficient iPSC generation from hBMMSCs using the compounds of p53 siRNA, valproic acid (VPA) and vitamin C (Vc) with four transcription factors OCT4, SOX2, KLF4, and c-MYC (compound induction system). The synergetic mechanism of the compounds was studied. Our results showed that the compound induction system could efficiently reprogramme hBMMSCs to iPSCs. hBMMSC-derived iPSC populations expressed pluripotent markers and had multi-potential to differentiate into three germ layer-derived cells. p53 siRNA, VPA and Vc had a synergetic effect on cell reprogramming and the combinatorial use of these substances greatly improved the efficiency of iPSC generation by suppressing the expression of p53, decreasing cell apoptosis, up-regulating the expression of the pluripotent gene OCT4 and modifying the cell cycle. Therefore, our study highlights a straightforward method for improving the speed and efficiency of iPSC generation and provides versatile tools for investigating early developmental processes such as haemopoiesis and relevant diseases. In addition, this study provides a paradigm for the combinatorial use of genetic factors and molecules to improve the efficiency of iPSC generation.

• MeSH
• biologické markery metabolismus   MeSH
• buněčné kultury metody   MeSH
• buněčný cyklus účinky léků   genetika   MeSH
• buňky kostní dřeně cytologie   účinky léků   metabolismus   MeSH
• down regulace genetika   účinky záření   MeSH
• indukované pluripotentní kmenové buňky cytologie   účinky léků   metabolismus   MeSH
• kyselina askorbová farmakologie   MeSH
• kyselina valproová farmakologie   MeSH
• lidé MeSH
• malá interferující RNA metabolismus   MeSH
• mezenchymální kmenové buňky cytologie   účinky léků   metabolismus   MeSH
• multipotentní kmenové buňky cytologie   metabolismus   MeSH
• myši inbrední ICR MeSH
• myši MeSH
• nádorový supresorový protein p53 metabolismus   MeSH
• oktamerní transkripční faktor 3 genetika   metabolismus   MeSH
• přeprogramování buněk účinky léků   genetika   MeSH
• upregulace účinky léků   genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

MicroRNA (miRNAs) are short noncoding RNA molecules involved in many cellular processes and shown to play a key role in somatic cell induced reprogramming. We performed an array based screening to identify candidates that are differentially expressed between dermal skin fibroblasts (DFs) and induced pluripotent stem cells (iPSCs). We focused our investigations on miR-145 and showed that this candidate is highly expressed in DFs relative to iPSCs and significantly downregulated during reprogramming process. Inhibition of miR-145 in DFs led to the induction of "cellular plasticity" demonstrated by: (a) alteration of cell morphology associated with downregulation of mesenchymal and upregulation of epithelial markers; (b) upregulation of pluripotency-associated genes including SOX2, KLF4, C-MYC; (c) downregulation of miRNA let-7b known to inhibit reprogramming; and (iv) increased efficiency of reprogramming to iPSCs in the presence of reprogramming factors. Together, our results indicate a direct functional link between miR-145 and molecular pathways underlying reprogramming of somatic cells to iPSCs.

• MeSH
• fibroblasty cytologie   metabolismus   MeSH
• indukované pluripotentní kmenové buňky cytologie   MeSH
• lidé MeSH
• mikro RNA genetika   metabolismus   MeSH
• molekulární sekvence - údaje MeSH
• přeprogramování buněk * genetika   MeSH
• regulace genové exprese MeSH
• reprodukovatelnost výsledků MeSH
• sekvence nukleotidů MeSH
• škára cytologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Human pluripotent stem cells have the potential to change the way in which human diseases are cured. Clinical-grade human embryonic stem cells and human induced pluripotent stem cells have to be created according to current good manufacturing practices and regulations. Quality and safety must be of the highest importance when humans' lives are at stake. With the rising number of clinical trials, there is a need for a consensus on hPSCs characterization. Here, we summarize mandatory and 'for information only' characterization methods with release criteria for the establishment of clinical-grade hPSC lines.

• MeSH
• Bacteria MeSH
• buněčná a tkáňová terapie metody   MeSH
• endotoxiny MeSH
• indukované pluripotentní kmenové buňky MeSH
• lidé MeSH
• lidské embryonální kmenové buňky MeSH
• Mycoplasma MeSH
• pluripotentní kmenové buňky * MeSH
• viry MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Neural differentiation of human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) can produce a valuable and robust source of human neural cell subtypes, holding great promise for the study of neurogenesis and development, and for treating neurological diseases. However, current hESCs and hiPSCs neural differentiation protocols require either animal factors or embryoid body formation, which decreases efficiency and yield, and strongly limits medical applications. Here we develop a simple, animal-free protocol for neural conversion of both hESCs and hiPSCs in adherent culture conditions. A simple medium formula including insulin induces the direct conversion of >98% of hESCs and hiPSCs into expandable, transplantable, and functional neural progenitors with neural rosette characteristics. Further differentiation of neural progenitors into dopaminergic and spinal motoneurons as well as astrocytes and oligodendrocytes indicates that these neural progenitors retain responsiveness to instructive cues revealing the robust applicability of the protocol in the treatment of different neurodegenerative diseases. The fact that this protocol includes animal-free medium and human extracellular matrix components avoiding embryoid bodies makes this protocol suitable for the use in clinic. Stem Cells Translational Medicine 2017;6:1217-1226.

• MeSH
• buněčná a tkáňová terapie MeSH
• buněčná diferenciace fyziologie   MeSH
• embryonální kmenové buňky fyziologie   MeSH
• indukované pluripotentní kmenové buňky cytologie   MeSH
• kultivované buňky MeSH
• lidé MeSH
• pluripotentní kmenové buňky cytologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Mucopolysaccharidosis type II (MPSII) is a rare X-linked lysosomal storage disorder caused by mutations in the iduronate-2-sulfatase (IDS) gene (IDS, Xq28). MPSII is characterized by skeletal deformities, hearing loss, airway obstruction, hepatosplenomegaly, cardiac valvular disease, and progressive neurological impairment. At the cellular level, IDS deficiency leads to lysosomal storage of glycosaminoglycans (GAGs), dominated by accumulation of dermatan and heparan sulfates. Human induced pluripotent stem cells (iPSC) represent an alternative system that complements the available MPSII murine model. Herein we report on the reprogramming of peripheral white blood cells from male and female MPSII patients into iPSC using a non-integrating protocol based on the Sendai virus vector system. We differentiated the iPSC lines into IDS deficient and GAG accumulating β-Tubulin III+ neurons, GFAP+ astrocytes, and CNPase+ oligodendrocytes. The lysosomal system in these cells displayed structural abnormalities reminiscent of those previously found in patient tissues and murine IDS deficient neuronal stem cells. Furthermore, quantitative determination of GAGs revealed a moderate increase in GAG levels in IDS deficient neurons and glia. We also tested the effects of recombinant IDS and found that the exogenous enzyme was internalized from the culture media and partially decreased the intracellular GAG levels in iPSC-derived neural cells; however, it failed to completely prevent accumulation of GAGs. In summary, we demonstrate that this human iPSC based model expresses the cellular and biochemical features of MPSII, and thus represents a useful experimental tool for further pathogenesis studies as well as therapy development and testing.

• MeSH
• astrocyty enzymologie   patologie   MeSH
• buněčný rodokmen MeSH
• fenotyp MeSH
• glykosaminoglykany metabolismus   MeSH
• iduronátsulfatasa genetika   metabolismus   MeSH
• indukované pluripotentní kmenové buňky enzymologie   patologie   MeSH
• kultivované buňky MeSH
• lidé MeSH
• lyzozomy enzymologie   patologie   MeSH
• mukopolysacharidóza II enzymologie   genetika   patologie   MeSH
• nervové kmenové buňky enzymologie   patologie   MeSH
• neurogeneze * MeSH
• neuroglie enzymologie   patologie   MeSH
• neurony enzymologie   patologie   MeSH
• oligodendroglie enzymologie   patologie   MeSH
• prekurzorové buňky oligodendrocytů enzymologie   patologie   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH