Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 72
Filtrar
1.
Haematologica ; 108(8): 2130-2145, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36794499

RESUMO

Sustained ANKRD26 expression associated with germline ANKRD26 mutations causes thrombocytopenia 2 (THC2), an inherited platelet disorder associated with a predisposition to leukemia. Some patients also present with erythrocytosis and/or leukocytosis. Using multiple human-relevant in vitro models (cell lines, primary patients' cells and patient-derived induced pluripotent stem cells) we demonstrate for the first time that ANKRD26 is expressed during the early steps of erythroid, megakaryocyte and granulocyte differentiation, and is necessary for progenitor cell proliferation. As differentiation progresses, ANKRD26 expression is progressively silenced, to complete the cellular maturation of the three myeloid lineages. In primary cells, abnormal ANKRD26 expression in committed progenitors directly affects the proliferation/differentiation balance for the three cell types. We show that ANKRD26 interacts with and crucially modulates the activity of MPL, EPOR and G-CSFR, three homodimeric type I cytokine receptors that regulate blood cell production. Higher than normal levels of ANKRD26 prevent the receptor internalization that leads to increased signaling and cytokine hypersensitivity. These findings afford evidence how ANKRD26 overexpression or the absence of its silencing during differentiation is responsible for myeloid blood cell abnormalities in patients with THC2.


Assuntos
Leucemia , Receptores de Citocinas , Humanos , Citocinas , Hematopoese , Leucemia/patologia , Diferenciação Celular , Peptídeos e Proteínas de Sinalização Intercelular
2.
Sci Rep ; 11(1): 13982, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234171

RESUMO

Samples used in biomedical research are often collected over years, in some cases from subjects that may have died and thus cannot be retrieved in any way. The value of these samples is priceless. Sample misidentification or mix-up are unfortunately common problems in biomedical research and can eventually result in the publication of incorrect data. Here we have compared the Fluidigm SNPtrace and the Agena iPLEX Sample ID panels for the authentication of human genomic DNA samples. We have tested 14 pure samples and simulated their cross-contamination at different percentages (2%, 5%, 10%, 25% and 50%). For both panels, we report call rate, allele intensity/probability score, performance in distinguishing pure samples and contaminated samples at different percentages, and sex typing. We show that both panels are reliable and efficient methods for sample authentication and we highlight their advantages and disadvantages. We believe that the data provided here is useful for sample authentication especially in biorepositories and core facility settings.


Assuntos
Bancos de Espécimes Biológicos/normas , Pesquisa Biomédica/normas , Identificação Biométrica , Pesquisa Biomédica/métodos , Identificação Biométrica/métodos , Contaminação por DNA , Feminino , Humanos , Masculino , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único
3.
J Histochem Cytochem ; 69(7): 451-460, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34142588

RESUMO

"Multi-Omics" technologies have contributed greatly to the understanding of various diseases by enabling researchers to accurately and rapidly investigate the molecular circuitry that connects cellular systems. The tissue-engineered, three-dimensional (3D), in vitro disease model "organoid" integrates the "omics" results in a model system, elucidating the complex links between genotype and phenotype. These 3D structures have been used to model cancer, infectious disease, toxicity, and neurological disorders. Here, we describe the advantage of using the tissue microarray (TMA) technology to analyze human-induced pluripotent stem cell-derived cerebral organoids. Compared with the conventional processing of individual samples, sectioning and staining of TMA slides are faster and can be automated, decreasing labor and reagent costs. The TMA technology faithfully captures cell morphology variations and detects specific biomarkers. The use of this technology can scale up organoid research results in at least two ways: (1) in the number of specimens that can be analyzed simultaneously and (2) in the number of consecutive sections that can be produced for analysis with different probes and antibodies.


Assuntos
Encéfalo/citologia , Organoides/citologia , Análise Serial de Tecidos , Diferenciação Celular , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Neurônios/citologia
4.
Elife ; 102021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34059198

RESUMO

Thrombocytopenic disorders have been treated with the Thrombopoietin-receptor agonist Eltrombopag. Patients with the same apparent form of thrombocytopenia may respond differently to the treatment. We describe a miniaturized bone marrow tissue model that provides a screening bioreactor for personalized, pre-treatment response prediction to Eltrombopag for individual patients. Using silk fibroin, a 3D bone marrow niche was developed that reproduces platelet biogenesis. Hematopoietic progenitors were isolated from a small amount of peripheral blood of patients with mutations in ANKRD26 and MYH9 genes, who had previously received Eltrombopag. The ex vivo response was strongly correlated with the in vivo platelet response. Induced Pluripotent Stem Cells (iPSCs) from one patient with mutated MYH9 differentiated into functional megakaryocytes that responded to Eltrombopag. Combining patient-derived cells and iPSCs with the 3D bone marrow model technology allows having a reproducible system for studying drug mechanisms and for individualized, pre-treatment selection of effective therapy in Inherited Thrombocytopenias.


Platelets are tiny cell fragments essential for blood to clot. They are created and released into the bloodstream by megakaryocytes, giant cells that live in the bone marrow. In certain genetic diseases, such as Inherited Thrombocytopenia, the bone marrow fails to produce enough platelets: this leaves patients extremely susceptible to bruising, bleeding, and poor clotting after an injury or surgery. Certain patients with Inherited Thrombocytopenia respond well to treatments designed to boost platelet production, but others do not. Why these differences exist could be investigated by designing new test systems that recreate the form and function of bone marrow in the laboratory. However, it is challenging to build the complex and poorly understood bone marrow environment outside of the body. Here, Di Buduo et al. have developed an artificial three-dimensional miniature organ bioreactor system that recreates the key features of bone marrow. In this system, megakaryocytes were grown from patient blood samples, and hooked up to a tissue scaffold made of silk. The cells were able to grow as if they were in their normal environment, and they could shed platelets into an artificial bloodstream. After treating megakaryocytes with drugs to stimulate platelet production, Di Buduo et al. found that the number of platelets recovered from the bioreactor could accurately predict which patients would respond to these drugs in the clinic. This new test system enables researchers to predict how a patient will respond to treatment, and to tailor therapy options to each individual. This technology could also be used to test new drugs for Inherited Thrombocytopenias and other blood-related diseases; if scaled-up, it could also, one day, generate large quantities of lab-grown blood cells for transfusion.


Assuntos
Benzoatos/farmacologia , Plaquetas/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Hidrazinas/farmacologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Megacariócitos/efeitos dos fármacos , Pirazóis/farmacologia , Receptores de Trombopoetina/agonistas , Nicho de Células-Tronco , Trombocitopenia/tratamento farmacológico , Trombopoese/efeitos dos fármacos , Adulto , Idoso , Reatores Biológicos , Plaquetas/metabolismo , Técnicas de Cultura de Células , Células Cultivadas , Feminino , Fibroínas/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Megacariócitos/metabolismo , Pessoa de Meia-Idade , Miniaturização , Mutação , Cadeias Pesadas de Miosina/genética , Receptores de Trombopoetina/metabolismo , Trombocitopenia/sangue , Trombocitopenia/genética , Adulto Jovem
5.
BioTech (Basel) ; 10(3)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35822767

RESUMO

BACKGROUND: The emergence of "multi-omics" and "multi-parametric" types of analysis based on a high number of biospecimens enforces the use of a great number of high-quality "Biological Materials and Associated Data" (BMaD). To meet the demands of biomedical research, several Biological Resource Centers (BRCs) or Biobanks world-wide have implemented a specific Quality Management System (QMS) certified ISO 9001:2015 or accredited by CAP9 ISO 20387:2018. For the first time, ISO, with the support of several Biobanking experts, issued the ISO 20387:2018 which is the first ISO norm specific for Biobanks. The fundamental difference with present certification/accreditation standards is that the ISO 20387:2018 focuses not only on the operational aspects of the Biobank, but also on the "competence of the Biobank to carry our specific Biobanking tasks". METHODS: The accreditation process for ISO 20387:2018 required the definition of: (1) objectives, goals and organizational structure of the Biobank, including procedures for governance, confidentiality and impartiality policies; (2) standard operating procedures (SOPs) of all activities performed, including acquisition, analysis, collection, data management, distribution, preparation, preservation, testing facility and equipment maintenance, calibration, and monitoring; (3) procedures for control of documents and records, the identification of risks and opportunities, improvements, corrective actions, nonconforming records and evaluation of external providers (4) an internal audit and management reviews, verification of QMS performance, monitoring of quality objectives and personnel qualification and competency in carrying out specific Biobanking tasks. RESULTS: The accreditation process is performed by an independent authorized organization which certifies that all processes are performed according to the QMS, and that the infrastructure is engineered and managed according to the GDP and/or GMP guidelines. CONCLUSION: Accreditation is given by an accreditation body, which recognizes formally that the Biobank is "competent to carry out specific Biobanking tasks".

6.
J Pathol Clin Res ; 6(1): 17-29, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31111685

RESUMO

Suppressor of Lin-12-like (C. elegans) (SEL1L) participates in the endoplasmic reticulum-associated protein degradation pathway, malignant transformation and stem cell biology. We explored the role of SEL1L in 110 adult gliomas, of different molecular subtype and grade, in relation to cell proliferation, stemness, glioma-associated microglia/macrophages (GAMs), prognostic markers and clinical outcome. SEL1L protein expression was assessed by immunohistochemistry and Western blotting. Genetic and epigenetic alterations were detected by molecular genetics techniques. SEL1L was overexpressed in anaplastic gliomas (World Health Organization [WHO] grade III) and in glioblastoma (GB, WHO grade IV) with the highest labelling index (LI) in the latter. Immunoreactivity was significantly associated with histological grade (p = 0.002) and cell proliferation index Ki-67/MIB-1 (p = 0.0001). In GB, SEL1L co-localised with stemness markers Nestin and Sox2. Endothelial cells and vascular pericytes of proliferative tumour blood vessels expressed SEL1L suggesting a role in tumour neo-vasculature. GAMs consistently expressed SEL1L. SEL1L overexpression was significantly associated with TERT promoter mutations (p = 0.0001), EGFR gene amplification (p = 0.0013), LOH on 10q (p = 0.0012) but was mutually exclusive with IDH1/2 mutations (p = 0.0001). SEL1L immunoreactivity correlated with tumour progression and cell proliferation, conditioning poor patient survival and response to therapy. This study emphasises SEL1L as a potential biomarker for the most common subgroup of TERT mutant/EGFR amplified/IDH-WT GBs.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Proteínas/metabolismo , Neoplasias Encefálicas/genética , Receptores ErbB/genética , Amplificação de Genes , Glioma/genética , Humanos , Mutação , Telomerase/genética
7.
Mov Disord ; 35(3): 401-408, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31724242

RESUMO

BACKGROUND: Although Huntington's disease (HD) is caused by a single dominant gene, it is clear that there are genetic modifiers that may influence the age of onset and disease progression. OBJECTIVES: We sought to investigate whether new inflammation-related genetic variants may contribute to the onset and progression of HD. METHODS: We first used postmortem brain material from patients at different stages of HD to look at the protein expression of toll-like receptor 4 (TLR4) and triggering receptor expressed on myeloid cells 2 (TREM2). We then genotyped the TREM2 R47H gene variant and 3 TLR4 single nucleotide polymorphisms in a large cohort of HD patients from the European Huntington's Disease Network REGISTRY. RESULTS: We found an increase in the number of cells expressing TREM2 and TLR4 in postmortem brain samples from patients dying with HD. We also found that the TREM2 R47H gene variant was associated with changes in cognitive decline in the large cohort of HD patients, whereas 2 of 3 TLR4 single nucleotide polymorphisms assessed were associated with changes in motor progression in this same group. CONCLUSIONS: These findings identify TREM2 and TLR4 as potential genetic modifiers for HD and suggest that inflammation influences disease progression in this condition. © 2019 International Parkinson and Movement Disorder Society.


Assuntos
Doença de Alzheimer , Doença de Huntington , Encéfalo , Humanos , Doença de Huntington/genética , Glicoproteínas de Membrana/genética , Células Mieloides , Receptores Imunológicos/genética , Receptor 4 Toll-Like/genética
8.
Br J Cancer ; 121(9): 768-775, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31558803

RESUMO

BACKGROUND: Current approaches aimed at inducing immunogenic cell death (ICD) to incite an immune response against cancer neoantigens are based on the use of chemotherapeutics and other agents. Results are hampered by issues of efficacy, combinatorial approaches, dosing and toxicity. Here, we adopted a strategy based on the use of an immunomolecule that overcomes pharmachemical limitations. METHODS: Cytofluorometry, electron microscopy, RT-PCR, western blotting, apotome immunofluorescence, MLR and xenografts. RESULTS: We report that an ICD process can be activated without the use of pharmacological compounds. We show that in Kras-mut/TP53-mut colorectal cancer cells the 15 kDa ßGBP cytokine, a T cell effector with onco-suppressor properties and a potential role in cancer immunosurveillance, induces key canonical events required for ICD induction. We document ER stress, autophagy that extends from cancer cells to the corresponding xenograft tumours, CRT cell surface shifting, ATP release and evidence of dendritic cell activation, a process required for priming cytotoxic T cells into a specific anticancer immunogenic response. CONCLUSIONS: Our findings provide experimental evidence for a rationale to explore a strategy based on the use of an immunomolecule that as a single agent couples oncosuppression with the activation of procedures necessary for the induction of long term response to cancer.


Assuntos
Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Proteínas Proto-Oncogênicas p21(ras)/imunologia , Trifosfato de Adenosina/imunologia , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Morte Celular Autofágica/efeitos dos fármacos , Morte Celular Autofágica/imunologia , Calreticulina/imunologia , Calreticulina/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Morte Celular/imunologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/imunologia , Feminino , Galectinas/farmacologia , Xenoenxertos , Humanos , Vigilância Imunológica , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos
10.
Stem Cell Res ; 31: 102-112, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30071393

RESUMO

The successful exploitation of human pluripotent stem cells (hPSCs) for research, translational or commercial reasons requires the implementation of a simple and efficient cryopreservation method. Cryopreservation is usually performed with dimethylsulphoxide (DMSO), in addition to animal proteins. However, even at sub-toxic levels, DMSO diminishes the pluripotency capacity of hPSCs and affects their epigenetic system by acting on the three DNA methyltransferases (Dnmts) and histone modification enzymes. Our study aimed to test trehalose-based cryosolutions containing ethylene glycol (EG) or glycerol (GLY) on hESCs RC17, hiPSCs CTR2#6 and long-term neuroepithelial-like stem cells (lt-NES) AF22. Here, we demostrate the effectiveness of these cryosolutions in hPSCs by showing an acceptable rate of cell viability and high stability compared to standard 10% DMSO freezing medium (CS10). All cell lines retained their morphology, self renewal potential and pluripotency, and none of the cryosolutions affected their differentiation potential. Genotoxicity varied among different stem cells types, while trehalose-based cryopreservation did not sensibly alter the homeostasis of endoplasmic reticulum (ER). This study provides evidence that pluripotent and neural stem cells stored in trehalose alone or with other cryoprotectants (CPAs) maintain their functional properties, indicating their potential use in cell therapies if produced in good manufacturing practice (GMP) facility.


Assuntos
Criopreservação/métodos , Células-Tronco Pluripotentes/metabolismo , Trealose/metabolismo , Humanos
11.
Stem Cells Dev ; 27(4): 287-295, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29239282

RESUMO

Wolfram syndrome (WFS) is a rare autosomal premature aging syndrome that shows signs of diabetes mellitus, optic atrophy, and deafness in addition to central nervous system and endocrine complications. The frequent form of WFS type 1 (WFS1) harbors causative mutations in the WFS1 gene, whereas the rare form or WFS type 2 (WFS2) involves CISD2. Mutations in these two genes are recognized by a subset of variable clinical symptoms and a set of overlapping features. In this study, we report on the generation of stable human-induced pluripotent stem cells (hiPSCs) derived from primary fibroblasts of a previously reported Italian family with CISD2 mutation (c.103 + 1G>A), occurring in the consensus intron 1 splicing site in two sisters, deleting the first exon of the transcript. The generated hiPSCs provide a cell model system to study the mutation's role in the multisystemic clinical disorders previously described and test eventual drug effects on the specific and associated clinical phenotype.


Assuntos
Senilidade Prematura/genética , Perda Auditiva Neurossensorial/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas de Membrana/genética , Doenças Mitocondriais/genética , Mutação , Atrofia Óptica/genética , Senilidade Prematura/patologia , Proliferação de Células/genética , Células Cultivadas , Saúde da Família , Feminino , Fibroblastos/metabolismo , Perda Auditiva Neurossensorial/patologia , Humanos , Íntrons/genética , Masculino , Doenças Mitocondriais/patologia , Atrofia Óptica/patologia , Sítios de Splice de RNA/genética , Irmãos
12.
J Cell Physiol ; 233(7): 5396-5404, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29215726

RESUMO

SEL1L (suppressor/enhancer of Lin-12-like) is a highly conserved gene associated with the endoplasmic reticulum-associated degradation (ERAD) pathway and involved in mediating the balance between stem cells self-renewal and differentiation of neural progenitors. It has been recently shown that SEL1L KO mice are embryonic lethal and display altered organogenesis. To better characterize the function of SEL1L in the early stages of embryonic development, we turned to the zebrafish model (Danio rerio). After exploring sel1l expression by RT-PCR and in situ hybridization, we employed a morpholino-mediated down-regulation approach. Results showed extensive impairments in the vasculature, which supports the mice knock-out findings.


Assuntos
Desenvolvimento Embrionário/genética , Degradação Associada com o Retículo Endoplasmático/genética , Retículo Endoplasmático/genética , Ubiquitina-Proteína Ligases/genética , Animais , Vasos Sanguíneos/crescimento & desenvolvimento , Vasos Sanguíneos/metabolismo , Retículo Endoplasmático/metabolismo , Endotélio/citologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento , Proteínas de Peixe-Zebra/genética
13.
J Cell Physiol ; 233(4): 3152-3163, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28816361

RESUMO

mSEL-1L is a highly conserved ER-resident type I protein, involved in the degradation of misfolded peptides through the ubiquitin-proteasome system (UPS), a pathway known to control the plasticity of the vascular smooth muscle cells (VSMC) phenotype and survival. In this article, we demonstrate that mSEL-1L deficiency interferes with the murine embryonic vascular network, showing particular irregularities in the intracranic and intersomitic neurovascular units and in the cerebral capillary microcirculation. During murine embryogenesis, mSEL-1L is expressed in cerebral areas known to harbor progenitor neural cells, while in the adult brain the protein is specifically restricted to the stem cell niches, co-localizing with Sox2 and Nestin. Null mice are characterized by important defects in the development of telenchephalic regions, revealing conspicuous aberration in neural stem cell lineage commitment. Moreover, mSEL-1L depletion in vitro and in vivo appears to affect the harmonic differentiation of the NSCs, by negatively influencing the corticogenesis processes. Overall, the data presented suggests that the drastic phenotypic characteristics exhibited in mSEL-1L null mice can, in part, be explained by the negative influence it plays on Notch1 signaling pathway.


Assuntos
Linhagem da Célula , Neovascularização Fisiológica , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Proteínas/metabolismo , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Proliferação de Células , Autorrenovação Celular , Genoma , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos Knockout , Receptores Notch/metabolismo , Transcriptoma/genética
14.
Mol Cell Neurosci ; 82: 46-57, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28476540

RESUMO

DNA methylation (DNAm) changes are of increasing relevance to neurodegenerative disorders, including Huntington's disease (HD). We performed genome-wide screening of possible DNAm changes occurring during striatal differentiation in human induced pluripotent stem cells derived from a HD patient (HD-hiPSCs) as cellular model. We identified 240 differentially methylated regions (DMRs) at promoters in fully differentiated HD-hiPSCs. Subsequently, we focused on the methylation differences in a subcluster of genes related to Jumonji Domain Containing 3 (JMJD3), a demethylase that epigenetically regulates neuronal differentiation and activates neuronal progenitor associated genes, which are indispensable for neuronal fate acquisition. Noticeably among these genes, WD repeat-containing protein 5 (WDR5) promoter was found hypermethylated in HD-hiPSCs, resulting in a significant down-modulation in its expression and of the encoded protein. A similar WDR5 expression decrease was seen in a small series of HD-hiPSC lines characterized by different CAG length. The decrease in WDR5 expression was particularly evident in HD-hiPSCs compared to hESCs and control-hiPSCs from healthy subjects. WDR5 is a core component of the MLL/SET1 chromatin remodeling complexes essential for H3K4me3, previously reported to play an important role in stem cells self-renewal and differentiation. These results suggest the existence of epigenetic mechanisms in HD and the identification of genes, which are able to modulate HD phenotype, is important both for biomarker discovery and therapeutic interventions.


Assuntos
Diferenciação Celular/genética , Epigênese Genética/genética , Histona-Lisina N-Metiltransferase/genética , Doença de Huntington/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Linhagem Celular , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina/genética , Humanos , Doença de Huntington/genética , Peptídeos e Proteínas de Sinalização Intracelular , Neurônios/metabolismo
15.
Biopreserv Biobank ; 15(4): 384-392, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28388226

RESUMO

Human induced pluripotent stem cell (hiPSC) biobanks are invaluable resources for basic and clinical research, since they provide a sustainable supply of accessible cell lines that meet high quality and safety standards. hiPSCs are particularly useful for understanding disease mechanisms, creating cell models for drug development, and generating novel clinical therapies. For clinical applications and drug discovery, it is fundamental that the acquired pluripotent cell lines never touch animal-derived products nor xenogeneic reagents (Good Manufacturing Practice-grade); whereas for research grade, it is sufficient to operate under Good Laboratory Practice conditions. However, regardless of the end use, it is important that every step in the whole process, starting from the original cells throughout expansion and manipulation, must be performed and recorded rigorously. Here, we describe our biobanking management system that is applied specifically to human pluripotent stem cells.


Assuntos
Bancos de Espécimes Biológicos/normas , Células-Tronco Pluripotentes Induzidas , Pesquisa/normas , Manejo de Espécimes/normas , Humanos , Manejo de Espécimes/tendências
16.
J Histochem Cytochem ; 64(12): 739-751, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27798288

RESUMO

In the past decade, tissue microarray (TMA) technology has evolved as an innovative tool for high-throughput proteomics analysis and mainly for biomarker validation. Similarly, enormous amount of data can be obtained from the cell line macroarray (CLMA) technology, which developed from the TMA using formalin-fixed, paraffin-embedded cell pellets. Here, we applied CLMA technology in stem cell research and in particular to identify bona fide neogenerated human induced pluripotent stem cell (hiPSC) clones suitable for down the line differentiation. All hiPSC protocols generate tens of clones, which need to be tested to determine genetically stable cell lines suitable for differentiation. Screening methods generally rely on fluorescence-activated cell sorting isolation and coverslip cell growth followed by immunofluorescence; these techniques could be cumbersome. Here, we show the application of CLMA to identify neogenerated pluripotent cell colonies and neuronal differentiated cell products. We also propose the use of the automated image analyzer, TissueQuest, as a reliable tool to quickly select the best clones, based upon the level of expression of multiple pluripotent biomarkers.


Assuntos
Células-Tronco Pluripotentes Induzidas/metabolismo , Análise Serial de Tecidos/métodos , Diferenciação Celular , Linhagem Celular , Ensaios de Triagem em Larga Escala , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Neurônios/citologia
17.
Stem Cells Dev ; 24(20): 2366-77, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26132372

RESUMO

The potential use of human embryonic stem cells (hESCs) in cell-based therapies points out the critical importance of epigenomic evaluation for cell-based therapies. Specifically, DNA methylation appears to be a crucial player in establishing cell fate commitment and lineage choices. In this study, we report the global changes observed on the CpG islands distributed in promoters, gene bodies, and intergenic regions and the major biochemical pathways and genes involved in methylation changes as H9-hESCs turn into a neuronal culture containing medium-sized spiny striatal neurons (MSNs). Using an ontogeny-recapitulating protocol of striatal neuron differentiation, we analyzed DNA methylation profiles during the conversion from pluripotency to neuropotency up to the acquisition of a mature neuronal phenotype. H9-hESCs changed the methylation pattern both through de novo methylation and hypomethylation of specific gene promoters. Bioinformatic analysis allowed us to identify a panel of striatal-associated genes, which were regulated by DNA methylation and differentially expressed during striatal commitment. Importantly, DNA methylation analysis revealed that H9-hESCs did not acquire methylation-based oncogenic properties after differentiation. Indeed, hypermethylation of cancer-associated genes that characterize transformed cells, such as Polycomb repressive complex-associated genes, was not detected in the neuronal cultures. However, the oncosuppressor gene, BCL2L11, became hypermethylated in H9-hESC-derived mature neurons. Whole-genome DNA methylation profiling could become a technological platform to predict the differentiative potential of hESC-derived cultures and establish further biosafety assessment quality control tools of the cell-based products.


Assuntos
Diferenciação Celular/genética , Metilação de DNA , Células-Tronco Embrionárias Humanas/citologia , Neurônios/citologia , Linhagem Celular , Corpo Estriado/citologia , Humanos , Fenótipo , Regiões Promotoras Genéticas/genética
18.
Oncotarget ; 6(14): 12452-67, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25948789

RESUMO

The suppressor of Lin-12-like (C. elegans) (SEL1L) is involved in the endoplasmic reticulum (ER)-associated degradation pathway, malignant transformation and stem cells. In 412 formalin-fixed and paraffin-embedded brain tumors and 39 Glioblastoma multiforme (GBM) cell lines, we determined the frequency of five SEL1L single nucleotide genetic variants with regulatory and coding functions by a SNaPShot™ assay. We tested their possible association with brain tumor risk, prognosis and therapy. We studied the in vitro cytotoxicity of valproic acid (VPA), temozolomide (TMZ), doxorubicin (DOX) and paclitaxel (PTX), alone or in combination, on 11 GBM cell lines, with respect to the SNP rs12435998 genotype. The SNP rs12435998 was prevalent in anaplastic and malignant gliomas, and in meningiomas of all histologic grades, but unrelated to brain tumor risks. In GBM patients, the SNP rs12435998 was associated with prolonged overall survival (OS) and better response to TMZ-based radio-chemotherapy. GBM stem cells with this SNP showed lower levels of SEL1L expression and enhanced sensitivity to VPA.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Quimiorradioterapia , Glioblastoma/genética , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Western Blotting , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Doxorrubicina/administração & dosagem , Genótipo , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Estimativa de Kaplan-Meier , Paclitaxel/administração & dosagem , Reação em Cadeia da Polimerase , Temozolomida , Ácido Valproico/administração & dosagem
20.
J Cell Physiol ; 230(8): 1770-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25502508

RESUMO

MicroRNAs (miRNAs) are important regulators of several cellular processes. During hematopoiesis, specific expression signatures have been reported in different blood cell lineages and stages of hematopoietic stem cell (HSC) differentiation. Here we explored the expression of miRNAs in umbilical cord blood stem (HSC) and progenitor cells (HPC) and compared it to unilineage granulocyte and granulo-monocyte differentiation as well as to primary blasts from patients with acute myeloid leukemia (AML). CD34 + CD38- ad CD34 + CD38 + cells were profiled using a global array consisting of about 2000 miRNAs. An approach combining bioinformatic prediction of miRNA targets with mRNA expression profiling was used to search for putative biologically enriched functions and networks. At least 15 miRNAs to be differentially expressed between HSC and HPC cell population, a cluster of 7 miRNAs are located in the q32 region of human chromosome 14 (miR-377-3p, -136-5p, 376a-3p, 495-3p, 654-3p, 376c-3p and 381-3p) whose expression decreased during the early stages of normal myelopoiesis but were markedly increased in a small set of AML. Interestingly, miR-4739 and -4516, two novel microRNA whose function and targets are presently unknown, showed specific and peculiar expression profile during the hematopoietic stem cells differentiation into unilineages and resulted strongly upregulated in almost all AML subsets. miR-181, -126-5p, -29b-3p and -22-3p resulted dis-regulated in specific leukemias phenotypes. This study provides the first evidence of a miRNA signature in human cord blood stem and progenitor cells with a potential role in hematopoietic stemness properties and possibly in leukemogenesis of specific AML subtypes.


Assuntos
Diferenciação Celular/genética , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Leucemia Mieloide Aguda/genética , MicroRNAs/genética , Transcriptoma/genética , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Biologia Computacional , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...