Aim: Human induced pluripotent stem cells (iPSCs) are inefficiently derived from somatic cells by overexpression of defined transcription factors. Overexpression of H2A histone variant macroH2A1.1, but not macroH2A1.2, leads to increased iPSC reprogramming by unclear mechanisms. Materials & methods: Cleavage under targets and tagmentation (CUT&Tag) allows robust epigenomic profiling of a low cell number. We performed an integrative CUT&Tag-RNA-Seq analysis of macroH2A1-dependent orchestration of iPSCs reprogramming using human endothelial cells. Results: We demonstrate wider genome occupancy, predicted transcription factors binding, and gene expression regulated by macroH2A1.1 during reprogramming, compared to macroH2A1.2. MacroH2A1.1, previously associated with neurodegenerative pathologies, specifically activated ectoderm/neural processes. Conclusion: CUT&Tag and RNA-Seq data integration is a powerful tool to investigate the epigenetic mechanisms occurring during cell reprogramming.

• Klíčová slova
• CUT&Tag, iPSCs, induced pluripotent stem cells, macroH2A1, reprogramming, somatic cells,
• MeSH
• endoteliální buňky metabolismus   MeSH
• histony * metabolismus   MeSH
• indukované pluripotentní kmenové buňky * metabolismus   MeSH
• lidé MeSH
• přeprogramování buněk genetika   MeSH
• sekvenování transkriptomu MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• histony * MeSH
• transkripční faktory MeSH

One of the challenges in clinical translation of cell-replacement therapies is the definition of optimal cell generation and storage/recovery protocols which would permit a rapid preparation of cell-treatment products for patient administration. Besides, the availability of injection devices that are simple to use is critical for potential future dissemination of any spinally targeted cell-replacement therapy into general medical practice. Here, we compared the engraftment properties of established human-induced pluripotent stem cells (hiPSCs)-derived neural precursor cell (NPCs) line once cells were harvested fresh from the cell culture or previously frozen and then grafted into striata or spinal cord of the immunodeficient rat. A newly developed human spinal injection device equipped with a spinal cord pulsation-cancelation magnetic needle was also tested for its safety in an adult immunosuppressed pig. Previously frozen NPCs showed similar post-grafting survival and differentiation profile as was seen for freshly harvested cells. Testing of human injection device showed acceptable safety with no detectable surgical procedure or spinal NPCs injection-related side effects.

• Klíčová slova
• cryopreservation, human induced pluripotent stem cells (hiPSCs), human injection device, immunosuppressed adult pig, neural precursor cells (NPCs), spinal cord,
• MeSH
• buněčná diferenciace fyziologie   MeSH
• dospělí MeSH
• genetické vektory genetika   MeSH
• indukované pluripotentní kmenové buňky * fyziologie   transplantace   MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• mícha MeSH
• mozek MeSH
• nervové kmenové buňky * fyziologie   transplantace   MeSH
• odběr biologického vzorku metody   MeSH
• odběr tkání a orgánů metody   MeSH
• prasata MeSH
• přeprogramování buněk * genetika   fyziologie   MeSH
• přežívání štěpu fyziologie   MeSH
• spinální injekce * škodlivé účinky   přístrojové vybavení   metody   MeSH
• transplantace kmenových buněk * škodlivé účinky   přístrojové vybavení   metody   MeSH
• virus Sendai MeSH
• výsledek terapie MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Embryonic stem cells and induced pluripotent stem cells provided us with fascinating new knowledge in recent years. Mechanistic insight into intricate regulatory circuitry governing pluripotency stemness and disclosing parallels between pluripotency stemness and cancer instigated numerous studies focusing on roles of pluripotency transcription factors, including Oct4, Sox2, Klf4, Nanog, Sall4 and Tfcp2L1, in cancer. Although generally well substantiated as tumour-promoting factors, oncogenic roles of pluripotency transcription factors and their clinical impacts are revealing themselves as increasingly complex. In certain tumours, both Oct4 and Sox2 behave as genuine oncogenes, and reporter genes driven by composite regulatory elements jointly recognized by both the factors can identify stem-like cells in a proportion of tumours. On the other hand, cancer stem cells seem to be biologically very heterogeneous both among different tumour types and among and even within individual tumours. Pluripotency transcription factors are certainly implicated in cancer stemness, but do not seem to encompass its entire spectrum. Certain cancer stem cells maintain their stemness by biological mechanisms completely different from pluripotency stemness, sometimes even by engaging signalling pathways that promote differentiation of pluripotent stem cells. Moreover, while these signalling pathways may well be antithetical to stemness in pluripotent stem cells, they may cooperate with pluripotency factors in cancer stem cells - a paradigmatic example is provided by the MAPK-AP-1 pathway. Unexpectedly, forced expression of pluripotency transcription factors in cancer cells frequently results in loss of their tumour-initiating ability, their phenotypic reversion and partial epigenetic normalization. Besides the very different signalling contexts operating in pluripotent and cancer stem cells, respectively, the pronounced dose dependency of reprogramming pluripotency factors may also contribute to the frequent loss of tumorigenicity observed in induced pluripotent cancer cells. Finally, contradictory cell-autonomous and non-cell-autonomous effects of various signalling molecules operate during pluripotency (cancer) reprogramming. The effects of pluripotency transcription factors in cancer are thus best explained within the concept of cancer stem cell heterogeneity.

• Klíčová slova
• AP-1, Cancer stem cells, Embryonic stem cells, Induced pluripotent cancer cells, Induced pluripotent stem cells, Pluripotency reprogramming, Pluripotency transcription factors, Sarcoma,
• MeSH
• buněčná diferenciace genetika   MeSH
• embryonální kmenové buňky MeSH
• indukované pluripotentní kmenové buňky * metabolismus   MeSH
• lidé MeSH
• nádory * genetika   metabolismus   MeSH
• oktamerní transkripční faktor 3 genetika   metabolismus   MeSH
• pluripotentní kmenové buňky * MeSH
• přeprogramování buněk genetika   MeSH
• transkripční faktory genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• oktamerní transkripční faktor 3 MeSH
• transkripční faktory MeSH

Significance: Since their discovery, induced pluripotent stem cells (iPSCs) had generated considerable interest in the scientific community for their great potential in regenerative medicine, disease modeling, and cell-based therapeutic approach, due to their unique characteristics of self-renewal and pluripotency. Recent Advances: Technological advances in iPSC genome-wide epigenetic profiling led to the elucidation of the epigenetic control of cellular identity during nuclear reprogramming. Moreover, iPSC physiology and metabolism are tightly regulated by oxidation-reduction events that mainly occur during the respiratory chain. In theory, iPSC-derived differentiated cells would be ideal for stem cell transplantation as autologous cells from donors, as the risks of rejection are minimal. Critical Issues: However, iPSCs experience high oxidative stress that, in turn, confers a high risk of increased genomic instability, which is most often linked to DNA repair deficiencies. Genomic instability has to be assessed before iPSCs can be used in therapeutic designs. Future Directions: This review will particularly focus on the links between redox balance and epigenetic modifications-in particular based on the histone variant macroH2A1-that determine DNA damage response in iPSCs and derived differentiated cells, and that might be exploited to decrease the teratogenic potential on iPSC transplantation. Antioxid. Redox Signal. 34, 335-349.

• Klíčová slova
• DNA damage, histone variant macroH2A1, induced pluripotent stem cells (iPSCs), oxidative stress,
• MeSH
• buněčná diferenciace * genetika   MeSH
• buněčná sebeobnova MeSH
• epigeneze genetická * MeSH
• indukované pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• lidé MeSH
• metylace DNA MeSH
• mitochondrie genetika   metabolismus   MeSH
• nádorová transformace buněk genetika   metabolismus   MeSH
• nestabilita genomu MeSH
• oxidace-redukce * MeSH
• oxidační stres MeSH
• oxidativní fosforylace MeSH
• pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• přeprogramování buněk genetika   MeSH
• regenerativní lékařství MeSH
• transplantace kmenových buněk MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Histone H3.3 glycine 34 to arginine/valine (G34R/V) mutations drive deadly gliomas and show exquisite regional and temporal specificity, suggesting a developmental context permissive to their effects. Here we show that 50% of G34R/V tumors (n = 95) bear activating PDGFRA mutations that display strong selection pressure at recurrence. Although considered gliomas, G34R/V tumors actually arise in GSX2/DLX-expressing interneuron progenitors, where G34R/V mutations impair neuronal differentiation. The lineage of origin may facilitate PDGFRA co-option through a chromatin loop connecting PDGFRA to GSX2 regulatory elements, promoting PDGFRA overexpression and mutation. At the single-cell level, G34R/V tumors harbor dual neuronal/astroglial identity and lack oligodendroglial programs, actively repressed by GSX2/DLX-mediated cell fate specification. G34R/V may become dispensable for tumor maintenance, whereas mutant-PDGFRA is potently oncogenic. Collectively, our results open novel research avenues in deadly tumors. G34R/V gliomas are neuronal malignancies where interneuron progenitors are stalled in differentiation by G34R/V mutations and malignant gliogenesis is promoted by co-option of a potentially targetable pathway, PDGFRA signaling.

• Klíčová slova
• GSX2, H3.3 G34R/V, PDGFRA, cell-of-origin, chromatin conformation, gliomas, interneuron progenitors, oncohistones, pediatric cancer, single-cell transcriptome,
• MeSH
• astrocyty metabolismus   patologie   MeSH
• biologické modely MeSH
• buněčný rodokmen MeSH
• chromatin metabolismus   MeSH
• embryo savčí metabolismus   MeSH
• epigeneze genetická MeSH
• genetická transkripce MeSH
• gliom genetika   patologie   MeSH
• histony genetika   metabolismus   MeSH
• interneurony metabolismus   MeSH
• karcinogeneze genetika   patologie   MeSH
• lysin metabolismus   MeSH
• mutace genetika   MeSH
• myši inbrední C57BL MeSH
• nádory mozku genetika   patologie   MeSH
• nervové kmenové buňky metabolismus   MeSH
• oligodendroglie metabolismus   MeSH
• přední mozek embryologie   MeSH
• přeprogramování buněk genetika   MeSH
• promotorové oblasti (genetika) genetika   MeSH
• regulace genové exprese u nádorů MeSH
• růstový faktor odvozený z trombocytů - receptor alfa genetika   metabolismus   MeSH
• stupeň nádoru MeSH
• transkriptom genetika   MeSH
• umlčování genů MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• chromatin MeSH
• histony MeSH
• lysin MeSH
• růstový faktor odvozený z trombocytů - receptor alfa MeSH

DNA damage can result from intrinsic cellular processes and from exposure to stressful environments. Such DNA damage generally threatens genome integrity and cell viability1. However, here we report that the transient induction of DNA strand breaks (single-strand breaks, double-strand breaks or both) in the moss Physcomitrella patens can trigger the reprogramming of differentiated leaf cells into stem cells without cell death. After intact leafy shoots (gametophores) were exposed to zeocin, an inducer of DNA strand breaks, the STEM CELL-INDUCING FACTOR 1 (STEMIN1)2 promoter was activated in some leaf cells. These cells subsequently initiated tip growth and underwent asymmetric cell divisions to form chloronema apical stem cells, which are in an earlier phase of the life cycle than leaf cells and have the ability to form new gametophores. This DNA-strand-break-induced reprogramming required the DNA damage sensor ATR kinase, but not ATM kinase, together with STEMIN1 and closely related proteins. ATR was also indispensable for the induction of STEMIN1 by DNA strand breaks. Our findings indicate that DNA strand breaks, which are usually considered to pose a severe threat to cells, trigger cellular reprogramming towards stem cells via the activity of ATR and STEMINs.

• MeSH
• listy rostlin genetika   růst a vývoj   MeSH
• mechy genetika   růst a vývoj   MeSH
• meristém genetika   růst a vývoj   MeSH
• poškození DNA fyziologie   MeSH
• přeprogramování buněk genetika   MeSH
• proliferace buněk MeSH
• zvětšování buněk * MeSH
• Publikační typ
• časopisecké články MeSH

Reprogramming of non-endocrine pancreatic cells into insulin-producing cells represents a promising therapeutic approach for the restoration of endogenous insulin production in diabetic patients. In this paper, we report that human organoid cells derived from the pancreatic tissue can be reprogrammed into the insulin-producing cells (IPCs) by the combination of in vitro transcribed modified mRNA encoding transcription factor neurogenin 3 and small molecules modulating the epigenetic state and signalling pathways. Upon the reprogramming, IPCs formed 4.6 ± 1.2 % of the total cells and expressed typical markers (insulin, glucokinase, ABCC8, KCNJ11, SLC2A2, SLC30A8) and transcription factors (PDX1, NEUROD1, MAFA, NKX2.2, NKX6.1, PAX4, PAX6) needed for the proper function of pancreatic β-cells. Additionally, we have revealed a positive effect of ALK5 inhibitor RepSox on the overall reprogramming efficiency. However, the reprogrammed IPCs possessed only a partial insulin-secretory capacity, as they were not able to respond to the changes in the extracellular glucose concentration by increasing insulin secretion. Based on the achieved results we conclude that due to the incomplete reprogramming, the IPCs have immature character and only partial properties of native human β-cells.

• MeSH
• antigen AC133 metabolismus   MeSH
• beta-buňky cytologie   účinky léků   MeSH
• dospělí MeSH
• genetická transkripce účinky léků   MeSH
• homeoboxový protein Nkx-2.2 MeSH
• homeodoménové proteiny MeSH
• inzulin biosyntéza   MeSH
• jaderné proteiny MeSH
• knihovny malých molekul farmakologie   MeSH
• lidé MeSH
• messenger RNA genetika   metabolismus   MeSH
• organoidy cytologie   MeSH
• přeprogramování buněk účinky léků   genetika   MeSH
• proliferace buněk MeSH
• proteiny nervové tkáně genetika   metabolismus   MeSH
• transkripční faktory bHLH genetika   metabolismus   MeSH
• transkripční faktory MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigen AC133 MeSH
• homeoboxový protein Nkx-2.2 MeSH
• homeodoménové proteiny MeSH
• inzulin MeSH
• jaderné proteiny MeSH
• knihovny malých molekul MeSH
• messenger RNA MeSH
• NEUROG3 protein, human MeSH Prohlížeč
• NKX2-2 protein, human MeSH Prohlížeč
• proteiny nervové tkáně MeSH
• transkripční faktory bHLH MeSH
• transkripční faktory MeSH

Monocytes play a major role in the defense against pathogens. They are rapidly mobilized to inflamed sites where they exert both proinflammatory and regulatory effector functions. It is still poorly understood how this dynamic and exceptionally plastic system is controlled at the molecular level. Herein, we evaluated the differentiation process that occurs in Ly6Chi monocytes during oral infection by Toxoplasma gondii. Flow cytometry and single-cell analysis revealed distinct activation status and gene expression profiles in the bone marrow, the spleen and the lamina propria of infected mice. We provide further evidence that acquisition of effector functions, such as the capacity to produce interleukin-27, is accompanied by distinct waves of epigenetic programming, highlighting a role for STAT1/IRF1 in the bone marrow and AP-1/NF-κB in the periphery. This work broadens our understanding of the molecular events that occur in vivo during monocyte differentiation in response to inflammatory cues.

• Klíčová slova
• Epigenetics in immune cells, Infection, Interleukins, Monocytes and macrophages,
• MeSH
• analýza jednotlivých buněk MeSH
• buněčná diferenciace imunologie   MeSH
• epigeneze genetická MeSH
• makrofágy imunologie   metabolismus   MeSH
• monocyty cytologie   imunologie   metabolismus   MeSH
• myši MeSH
• přeprogramování buněk genetika   MeSH
• stanovení celkové genové exprese MeSH
• Toxoplasma imunologie   MeSH
• toxoplazmóza genetika   imunologie   metabolismus   parazitologie   MeSH
• výpočetní biologie metody   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The potential clinical applications of human induced pluripotent stem cells (hiPSCs) are limited by genetic and epigenetic variations among hiPSC lines and the question of their equivalency with human embryonic stem cells (hESCs). We used MethylScreen technology to determine the DNA methylation profile of pluripotency and differentiation markers in hiPSC lines from different source cell types compared to hESCs and hiPSC source cells. After derivation, hiPSC lines compromised a heterogeneous population characterized by variable levels of aberrant DNA methylation. These aberrations were induced during somatic cell reprogramming and their levels were associated with the type of hiPSC source cells. hiPSC population heterogeneity was reduced during prolonged culture and hiPSCs acquired an hESC-like methylation profile. In contrast, the expression of differentiation marker genes in hiPSC lines remained distinguishable from that in hESCs. Taken together, in vitro culture facilitates hiPSC acquisition of hESC epigenetic characteristics. However, differences remain between both pluripotent stem cell types, which must be considered before their use in downstream applications.

• MeSH
• buněčná diferenciace genetika   MeSH
• buněčné linie MeSH
• fibroblasty cytologie   metabolismus   MeSH
• indukované pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• kultivované buňky MeSH
• lidé MeSH
• lidské embryonální kmenové buňky cytologie   metabolismus   MeSH
• metylace DNA * MeSH
• přeprogramování buněk genetika   MeSH
• shluková analýza MeSH
• stanovení celkové genové exprese MeSH
• vývojová regulace genové exprese MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články 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.

• Klíčová slova
• Induced pluripotent stem cells, KLF4, Mesenchymal-to-epithelial transition, OCT4, Reprogramming, SOX2, c-MYC, miR-145, microRNA,
• MeSH
• fibroblasty cytologie   metabolismus   MeSH
• indukované pluripotentní kmenové buňky cytologie   MeSH
• Krüppel-like faktor 4 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
• Názvy látek
• KLF4 protein, human MeSH Prohlížeč
• Krüppel-like faktor 4 MeSH
• mikro RNA MeSH
• MIRN145 microRNA, human MeSH Prohlížeč