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1.
Int J Nanomedicine ; 15: 6263-6277, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922002

RESUMO

Background: Nowadays, smart synthesized nanostructures have attracted wide attention in the field of stem cell nanotechnology due to their effect on different properties of stem cells. Methods: GFc7 growth nanofactor was synthesized based on nanochelating technology as an iron-containing copper chelator nanocomplex. The effect of this nanocomplex on the expansion and differentiation of hematopoietic stem cells (HSCs) as well as its performance as a cryoprotectant was evaluated in the present study. Results: The results showed that the absolute count of CD34+ and CD34+CD38- cells on days 4, 7, 10 and 13; the percentage of lactate dehydrogenase enzyme on the same days and CD34+CXCR4 population on day 10 were significantly increased when they were treated with GFc7 growth nanofactor in a fetal bovine serum (FBS)-free medium. This medium also led to delayed differentiation in HSCs. One noticeable result was that CD34+CD38- cells cultured in an FBS medium were immediately differentiated into CD34+CD38+ cells, while CD34+CD38- cells treated with GFc7 growth nanofactor in FBS medium did not show such an immediate significant differentiation. De-freezing GFc7-treated CD34+ cells, which were already frozen according to cord blood bank protocols, showed a higher percentage of cell viability and a larger number of colonies according to colony-forming cell assay as compared to control. Conclusion: It can be claimed that treating HSCs with GFc7 growth nanofactor leads to quality and quantity improvement of HSCs, both in terms of expansion in vitro and freezing and de-freezing processes.


Assuntos
Citoproteção , Células-Tronco Hematopoéticas/citologia , Nanopartículas/química , ADP-Ribosil Ciclase 1/metabolismo , Antígenos CD34/metabolismo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Difusão Dinâmica da Luz , Congelamento , Regulação da Expressão Gênica , Humanos , Nanopartículas/ultraestrutura , Receptores CXCR4/metabolismo
2.
Blood Adv ; 4(17): 4147-4150, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32886750

RESUMO

Donor registries and transplantation societies recommend cryopreservation of unrelated donor hemopoietic progenitor cell (HPC) products before the recipient commences conditioning therapy to mitigate the donor and travel risks associated with the COVID-19 pandemic. However, little is known regarding the postthaw quality of such allogeneic products or the effect of precryopreservation storage and processing on these characteristics. We investigated the postthaw CD34+ cell recovery and viability of 305 allogeneic HPC products cryopreserved at 9 laboratories across Australia. Median postthaw CD34+ cell recovery was 76% and ranged from 6% to 122%. Longer transit time before cryopreservation, white cell count (WCC) during storage, and complex product manipulation before cryopreservation were independently associated with inferior postthaw CD34+ cell recovery. Longer precryopreservation transit time and WCC were also associated with inferior postthaw CD34+ cell viability. We conclude that although postthaw CD34+ cell recovery and viability of cryopreserved allogeneic HPC is generally acceptable, there is a significant risk of poor postthaw product quality, associated with prolonged storage time, higher WCC, and complex product manipulation precryopreservation. Awareness of expected postthaw recovery and practices that influence it will assist collection, processing, and transplant centers in optimizing outcomes for transplant recipients.


Assuntos
Antígenos CD34/análise , Criopreservação , Células-Tronco Hematopoéticas/citologia , Sobrevivência Celular , Infecções por Coronavirus/epidemiologia , Transplante de Células-Tronco Hematopoéticas , Humanos , Pandemias , Pneumonia Viral/epidemiologia , Transplante Homólogo
3.
J Transl Med ; 18(1): 297, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32746922

RESUMO

BACKGROUND: The severe acute respiratory syndrome virus SARS-CoV-2, a close relative of the SARS-CoV virus, is the cause of the recent COVID-19 pandemic affecting, to date, over 14 million individuals across the globe and demonstrating relatively high rates of infection and mortality. A third virus, the H5N1, responsible for avian influenza, has caused infection with some clinical similarities to those in COVID-19 infections. Cytokines, small proteins that modulate immune responses, have been directly implicated in some of the severe responses seen in COVID-19 patients, e.g. cytokine storms. Understanding the immune processes related to COVID-19, and other similar infections, could help identify diagnostic markers and therapeutic targets. METHODS: Here we examine data of cytokine, immune cell types, and disease associations captured from biomedical literature associated with COVID-19, Coronavirus in general, SARS, and H5N1 influenza, with the objective of identifying potentially useful relationships and areas for future research. RESULTS: Cytokine and cell-type associations captured from Medical Subject Heading (MeSH) terms linked to thousands of PubMed records, has identified differing patterns of associations between the four corpuses of publications (COVID-19, Coronavirus, SARS, or H5N1 influenza). Clustering of cytokine-disease co-occurrences in the context of Coronavirus has identified compelling clusters of co-morbidities and symptoms, some of which already known to be linked to COVID-19. Finally, network analysis identified sub-networks of cytokines and immune cell types associated with different manifestations, co-morbidities and symptoms of Coronavirus, SARS, and H5N1. CONCLUSION: Systematic review of research in medicine is essential to facilitate evidence-based choices about health interventions. In a fast moving pandemic the approach taken here will identify trends and enable rapid comparison to the literature of related diseases.


Assuntos
Betacoronavirus , Infecções por Coronavirus/imunologia , Pneumopatias/imunologia , Pneumonia Viral/imunologia , Publicações , Análise por Conglomerados , Comorbidade , Síndrome da Liberação de Citocina/virologia , Citocinas/imunologia , Células-Tronco Hematopoéticas/citologia , Humanos , Sistema Imunitário , Virus da Influenza A Subtipo H5N1 , Influenza Humana/imunologia , Pandemias , PubMed , Síndrome Respiratória Aguda Grave/imunologia
4.
Nature ; 583(7817): 585-589, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32669716

RESUMO

Bone marrow transplantation therapy relies on the life-long regenerative capacity of haematopoietic stem cells (HSCs)1,2. HSCs present a complex variety of regenerative behaviours at the clonal level, but the mechanisms underlying this diversity are still undetermined3-11. Recent advances in single-cell RNA sequencing have revealed transcriptional differences among HSCs, providing a possible explanation for their functional heterogeneity12-17. However, the destructive nature of sequencing assays prevents simultaneous observation of stem cell state and function. To solve this challenge, we implemented expressible lentiviral barcoding, which enabled simultaneous analysis of lineages and transcriptomes from single adult HSCs and their clonal trajectories during long-term bone marrow reconstitution. Analysis of differential gene expression between clones with distinct behaviour revealed an intrinsic molecular signature that characterizes functional long-term repopulating HSCs. Probing this signature through in vivo CRISPR screening, we found the transcription factor TCF15 to be required and sufficient to drive HSC quiescence and long-term self-renewal. In situ, Tcf15 expression labels the most primitive subset of true multipotent HSCs. In conclusion, our work elucidates clone-intrinsic molecular programmes associated with functional stem cell heterogeneity and identifies a mechanism for the maintenance of the self-renewing HSC state.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem da Célula , Hematopoese , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Análise de Célula Única , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Sistemas CRISPR-Cas , Autorrenovação Celular , Feminino , Camundongos
5.
Nature ; 583(7815): 296-302, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612232

RESUMO

The mammalian immune system implements a remarkably effective set of mechanisms for fighting pathogens1. Its main components are haematopoietic immune cells, including myeloid cells that control innate immunity, and lymphoid cells that constitute adaptive immunity2. However, immune functions are not unique to haematopoietic cells, and many other cell types display basic mechanisms of pathogen defence3-5. To advance our understanding of immunology outside the haematopoietic system, here we systematically investigate the regulation of immune genes in the three major types of structural cells: epithelium, endothelium and fibroblasts. We characterize these cell types across twelve organs in mice, using cellular phenotyping, transcriptome sequencing, chromatin accessibility profiling and epigenome mapping. This comprehensive dataset revealed complex immune gene activity and regulation in structural cells. The observed patterns were highly organ-specific and seem to modulate the extensive interactions between structural cells and haematopoietic immune cells. Moreover, we identified an epigenetically encoded immune potential in structural cells under tissue homeostasis, which was triggered in response to systemic viral infection. This study highlights the prevalence and organ-specific complexity of immune gene activity in non-haematopoietic structural cells, and it provides a high-resolution, multi-omics atlas of the epigenetic and transcriptional networks that regulate structural cells in the mouse.


Assuntos
Endotélio/imunologia , Células Epiteliais/imunologia , Fibroblastos/imunologia , Regulação da Expressão Gênica/imunologia , Sistema Imunitário/citologia , Sistema Imunitário/imunologia , Especificidade de Órgãos/imunologia , Imunidade Adaptativa , Animais , Cromatina/genética , Cromatina/metabolismo , Endotélio/citologia , Epigênese Genética/imunologia , Epigenoma/genética , Células Epiteliais/citologia , Feminino , Fibroblastos/citologia , Regulação da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/imunologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Sistema Imunitário/virologia , Imunidade Inata , Coriomeningite Linfocítica/imunologia , Coriomeningite Linfocítica/virologia , Vírus da Coriomeningite Linfocítica/imunologia , Masculino , Camundongos , Especificidade de Órgãos/genética , Transcrição Genética/imunologia , Transcriptoma/genética
6.
Genes Dev ; 34(13-14): 950-964, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32499402

RESUMO

Hematopoietic stem cell (HSC) ontogeny is accompanied by dynamic changes in gene regulatory networks. We performed RNA-seq and histone mark ChIP-seq to define the transcriptomes and epigenomes of cells representing key developmental stages of HSC ontogeny in mice. The five populations analyzed were embryonic day 10.5 (E10.5) endothelium and hemogenic endothelium from the major arteries, an enriched population of prehematopoietic stem cells (pre-HSCs), fetal liver HSCs, and adult bone marrow HSCs. Using epigenetic signatures, we identified enhancers for each developmental stage. Only 12% of enhancers are primed, and 78% are active, suggesting the vast majority of enhancers are established de novo without prior priming in earlier stages. We constructed developmental stage-specific transcriptional regulatory networks by linking enhancers and predicted bound transcription factors to their target promoters using a novel computational algorithm, target inference via physical connection (TIPC). TIPC predicted known transcriptional regulators for the endothelial-to-hematopoietic transition, validating our overall approach, and identified putative novel transcription factors, including the broadly expressed transcription factors SP3 and MAZ. Finally, we validated a role for SP3 and MAZ in the formation of hemogenic endothelium. Our data and computational analyses provide a useful resource for uncovering regulators of HSC formation.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/genética , Redes Reguladoras de Genes/genética , Hematopoese/genética , Células-Tronco Hematopoéticas/citologia , Algoritmos , Animais , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos/genética , Epigênese Genética/genética , Edição de Genes , Camundongos , Fator de Transcrição Sp3/metabolismo , Fatores de Transcrição/metabolismo , Transcriptoma
7.
Nature ; 584(7819): 130-135, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32581364

RESUMO

The extent to which the biology of oncogenesis and ageing are shaped by factors that distinguish human populations is unknown. Haematopoietic clones with acquired mutations become common with advancing age and can lead to blood cancers1-10. Here we describe shared and population-specific patterns of genomic mutations and clonal selection in haematopoietic cells on the basis of 33,250 autosomal mosaic chromosomal alterations that we detected in 179,417 Japanese participants in the BioBank Japan cohort and compared with analogous data from the UK Biobank. In this long-lived Japanese population, mosaic chromosomal alterations were detected in more than 35.0% (s.e.m., 1.4%) of individuals older than 90 years, which suggests that such clones trend towards inevitability with advancing age. Japanese and European individuals exhibited key differences in the genomic locations of mutations in their respective haematopoietic clones; these differences predicted the relative rates of chronic lymphocytic leukaemia (which is more common among European individuals) and T cell leukaemia (which is more common among Japanese individuals) in these populations. Three different mutational precursors of chronic lymphocytic leukaemia (including trisomy 12, loss of chromosomes 13q and 13q, and copy-neutral loss of heterozygosity) were between two and six times less common among Japanese individuals, which suggests that the Japanese and European populations differ in selective pressures on clones long before the development of clinically apparent chronic lymphocytic leukaemia. Japanese and British populations also exhibited very different rates of clones that arose from B and T cell lineages, which predicted the relative rates of B and T cell cancers in these populations. We identified six previously undescribed loci at which inherited variants predispose to mosaic chromosomal alterations that duplicate or remove the inherited risk alleles, including large-effect rare variants at NBN, MRE11 and CTU2 (odds ratio, 28-91). We suggest that selective pressures on clones are modulated by factors that are specific to human populations. Further genomic characterization of clonal selection and cancer in populations from around the world is therefore warranted.


Assuntos
Envelhecimento/genética , Aberrações Cromossômicas , Cromossomos Humanos/genética , Células Clonais/metabolismo , Genoma Humano/genética , Células-Tronco Hematopoéticas/metabolismo , Mutação , Idoso de 80 Anos ou mais , Alelos , Linhagem da Célula , Células Clonais/citologia , Células Clonais/patologia , Estudos de Coortes , Feminino , Loci Gênicos/genética , Hematopoese/genética , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/patologia , Humanos , Japão , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Leucemia de Células T/genética , Leucemia de Células T/patologia , Masculino , Mosaicismo , Reino Unido
8.
Nat Commun ; 11(1): 2722, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483172

RESUMO

Mammalian gene expression patterns are controlled by regulatory elements, which interact within topologically associating domains (TADs). The relationship between activation of regulatory elements, formation of structural chromatin interactions and gene expression during development is unclear. Here, we present Tiled-C, a low-input chromosome conformation capture (3C) technique. We use this approach to study chromatin architecture at high spatial and temporal resolution through in vivo mouse erythroid differentiation. Integrated analysis of chromatin accessibility and single-cell expression data shows that regulatory elements gradually become accessible within pre-existing TADs during early differentiation. This is followed by structural re-organization within the TAD and formation of specific contacts between enhancers and promoters. Our high-resolution data show that these enhancer-promoter interactions are not established prior to gene expression, but formed gradually during differentiation, concomitant with progressive upregulation of gene activity. Together, these results provide new insight into the close, interdependent relationship between chromatin architecture and gene regulation during development.


Assuntos
Diferenciação Celular/genética , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica no Desenvolvimento , Genoma/genética , Regiões Promotoras Genéticas/genética , Células-Tronco/metabolismo , Animais , Células Cultivadas , Cromatina/genética , Cromossomos de Mamíferos/genética , Feminino , Perfilação da Expressão Gênica/métodos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco/citologia
9.
PLoS One ; 15(6): e0234638, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569325

RESUMO

Hematopoietic stem cell transplantation is successfully applied since the late 1950s; however, its efficacy still needs to be increased. A promising strategy is to transplant high numbers of pluripotent hematopoietic stem cells (HSCs). Therefore, an improved ex vivo culture system that supports proliferation and maintains HSC pluripotency would override possible limitations in cell numbers gained from donors. To model the natural HSC niche in vitro, we optimized the HSC medium composition with a panel of cytokines and valproic acid and used an artificial 3D bone marrow-like scaffold made of polydimethylsiloxane (PDMS). This 3D scaffold offered a suitable platform to amplify human HSCs in vitro and, simultaneously, to support their viability, multipotency and ability for self-renewal. Silicon oxide-covering of PDMS structures further improved amplification of CD34+ cells, although the conservation of naïve HSCs was better on non-covered 3D PDMS. Finally, we found that HSC cultivated on non-covered 3D PDMS generated most pluripotent colonies within colony forming unit assays. In conclusion, by combining biological and biotechnological approaches, we optimized in vitro HSCs culture conditions, resulting in improved amplification, multipotency maintenance and vitality of HSCs.


Assuntos
Materiais Biomiméticos/farmacologia , Células-Tronco Hematopoéticas/citologia , Nicho de Células-Tronco , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colágeno/farmacologia , Dimetilpolisiloxanos/farmacologia , Feminino , Fibronectinas/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Masculino , Purinas/farmacologia , Nicho de Células-Tronco/efeitos dos fármacos , Ácido Valproico/farmacologia
10.
Nat Commun ; 11(1): 3013, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541654

RESUMO

B lymphoid development is initiated by the differentiation of hematopoietic stem cells into lineage committed progenitors, ultimately generating mature B cells. This highly regulated process generates clonal immunological diversity via recombination of immunoglobulin V, D and J gene segments. While several transcription factors that control B cell development and V(D)J recombination have been defined, how these processes are initiated and coordinated into a precise regulatory network remains poorly understood. Here, we show that the transcription factor ETS Related Gene (Erg) is essential for early B lymphoid differentiation. Erg initiates a transcriptional network involving the B cell lineage defining genes, Ebf1 and Pax5, which directly promotes expression of key genes involved in V(D)J recombination and formation of the B cell receptor. Complementation of Erg deficiency with a productively rearranged immunoglobulin gene rescued B lineage development, demonstrating that Erg is an essential and stage-specific regulator of the gene regulatory network controlling B lymphopoiesis.


Assuntos
Linfócitos B/metabolismo , Diferenciação Celular/genética , Células-Tronco Hematopoéticas/metabolismo , Linfopoese/genética , Proteínas Oncogênicas/genética , Transcrição Genética , Regulador Transcricional ERG/genética , Animais , Linfócitos B/citologia , Linhagem da Célula/genética , Células Cultivadas , Redes Reguladoras de Genes/genética , Células-Tronco Hematopoéticas/citologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Oncogênicas/metabolismo , Fator de Transcrição PAX5/genética , Fator de Transcrição PAX5/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulador Transcricional ERG/metabolismo , Recombinação V(D)J/genética
11.
J Leukoc Biol ; 107(6): 1175-1185, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32374077

RESUMO

Treatment with the CXCR4 antagonist, plerixafor (AMD3100), has been proposed for clinical use in patients with WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome and in pulmonary fibrosis. However, there is controversy with respect to the impact of plerixafor on neutrophil dynamics in the lung, which may affect its safety profile. In this study, we investigated the kinetics of endogenous neutrophils by direct imaging, using confocal intravital microscopy in mouse bone marrow, spleen, and lungs. Neutrophils are observed increasing their velocity and exiting the bone marrow following plerixafor administration, with a concomitant increase in neutrophil numbers in the blood and spleen, while the marginated pool of neutrophils in the lung microvasculature remained unchanged in terms of numbers and cell velocity. Use of autologous radiolabeled neutrophils and SPECT/CT imaging in healthy volunteers showed that plerixafor did not affect GM-CSF-primed neutrophil entrapment or release in the lungs. Taken together, these data suggest that plerixafor causes neutrophil mobilization from the bone marrow but does not impact on lung marginated neutrophil dynamics and thus is unlikely to compromise respiratory host defense both in humans and mice.


Assuntos
Medula Óssea/efeitos dos fármacos , Mobilização de Células-Tronco Hematopoéticas/métodos , Compostos Heterocíclicos/farmacologia , Pulmão/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Baço/efeitos dos fármacos , Animais , Medula Óssea/diagnóstico por imagem , Medula Óssea/imunologia , Rastreamento de Células/métodos , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/imunologia , Humanos , Contagem de Leucócitos , Pulmão/citologia , Pulmão/diagnóstico por imagem , Pulmão/imunologia , Camundongos Endogâmicos C57BL , Neutrófilos/citologia , Neutrófilos/imunologia , Compostos Radiofarmacêuticos/administração & dosagem , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Baço/citologia , Baço/diagnóstico por imagem , Baço/imunologia , Tecnécio/administração & dosagem
12.
Exp Hematol ; 86: 1-14, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32422232

RESUMO

The CD34 cell surface antigen is widely expressed in tissues on cells with progenitor-like properties and on mature vascular endothelia. In adult human bone marrow, CD34 marks hematopoietic stem and progenitor cells (HSPCs) starting from the bulk of hematopoietic stem cells with long-term repopulating potential (LT-HSCs) throughout expansion and differentiation of oligopotent and unipotent progenitors. CD34 protein surface expression is typically lost as cells mature into terminal effectors. Because of this expression pattern of HSPCs, CD34 has had a central role in the evaluation or selection of donor graft tissue in HSC transplant (HSCT). Given its clinical importance, it is surprising that the biological functions of CD34 are still poorly understood. This enigma is due, in part, to CD34's context-specific role as both a pro-adhesive and anti-adhesive molecule and its potential functional redundancy with other sialomucins. Moreover, there are also critical differences in the regulation of CD34 expression on HSPCs in humans and experimental mice. In this review, we highlight some of the more well-defined functions of CD34 in HSPCs with a focus on proposed functions most relevant to HSCT biology.


Assuntos
Antígenos CD34/metabolismo , Diferenciação Celular , Células-Tronco Hematopoéticas/metabolismo , Animais , Medula Óssea/metabolismo , Regulação da Expressão Gênica , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Humanos , Camundongos
13.
Exp Hematol ; 85: 3-7, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32437907

RESUMO

Hematopoiesis refers to the developmental process generating all blood lineages. In vertebrates, there are multiple waves of hematopoiesis, which emerge in distinct anatomic locations at different times and give rise to different blood lineages. In the last decade, numerous lineage-tracing studies have been conducted to investigate the hierarchical structure of the hematopoietic system. Yet, the majority of these lineage-tracing studies are not able to integrate the spatial-temporal information with the developmental potential of hematopoietic cells. With the newly developed infrared laser-evoked gene operator (IR-LEGO) microscope heating system, it is now possible to improve our understanding of hematopoiesis to spatial-temporal-controlled single-cell resolution. Here, we discuss the recent development of the IR-LEGO system and its applications in hematopoietic lineage tracing in vivo.


Assuntos
Linhagem da Célula/fisiologia , Rastreamento de Células , Hematopoese/fisiologia , Células-Tronco Hematopoéticas , Optogenética , Animais , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Raios Infravermelhos , Lasers
14.
PLoS One ; 15(5): e0233751, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32470079

RESUMO

Mesenchymal stromal cells are an important component of the bone marrow hematopoietic niche. Prior studies showed that signaling from members of the transforming growth factor (TGF) superfamily in mesenchymal stromal cells is required for normal niche development. Here, we assessed the impact of TGF family signaling on niche maintenance and stress responses by deleting Smad4 in mesenchymal stromal cells at birth, thereby abrogating canonical TGF signaling. No alteration in the number or spatial organization of CXCL12-abundant reticular (CAR) cells, osteoblasts, or adipocytes was observed in Osx-Cre, Smad4fl/fl mice, and expression of key niche factors was normal. Basal hematopoiesis and stress erythropoiesis responses to acute hemolytic anemia were normal. TGF-ß potently inhibits stromal CXCL12 expression in vitro; however, G-CSF induced decreases in bone marrow CXCL12 expression and subsequent hematopoietic stem/progenitor cell mobilization were normal in Osx-Cre, Tgfbr2fl/fl mice, in which all TGF-ß signaling in mesenchymal stromal is lost. Finally, although a prior study showed that TGF-ß enhances recovery from myeloablative therapy, hematopoietic recovery following single or multiple doses of 5-flurauracil were normal in Osx-Cre, Tgfbr2fl/fl mice. Collectively, these data suggest that TGF family member signaling in mesenchymal stromal cells is dispensable for hematopoietic niche maintenance under basal and stress conditions.


Assuntos
Anemia Hemolítica/metabolismo , Eritropoese , Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Fator de Crescimento Transformador beta/fisiologia , Fatores de Crescimento Transformadores/fisiologia , Doença Aguda , Anemia Hemolítica/patologia , Animais , Medula Óssea/metabolismo , Medula Óssea/patologia , Células Cultivadas , Quimiocina CXCL12/metabolismo , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/patologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Nicho de Células-Tronco
15.
Nat Cell Biol ; 22(6): 630-639, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32367048

RESUMO

How transplanted haematopoietic stem cells (HSCs) behave soon after they reside in a preconditioned host has not been studied due to technical limitations. Here, using single-cell RNA sequencing, we first obtained the transcriptome-based classifications of 28 haematopoietic cell types. We then applied them in conjunction with functional assays to track the dynamic changes of immunophenotypically purified HSCs in irradiated recipients within the first week after transplantation. Based on our transcriptional classifications, most homed HSCs in bone marrow and spleen became multipotent progenitors and, occasionally, some HSCs gave rise to megakaryocytic-erythroid or myeloid precursors. Parallel in vitro and in vivo functional experiments supported the paradigm of robust differentiation without substantial HSC expansion during the first week. Therefore, this study uncovers the previously inaccessible kinetics and fate choices of transplanted HSCs in myeloablated recipients at early stage, with implications for clinical applications of HSCs and other stem cells.


Assuntos
Diferenciação Celular , Células Precursoras Eritroides/citologia , Células-Tronco Hematopoéticas/citologia , Megacariócitos/citologia , Células Mieloides/citologia , Análise de Célula Única/métodos , Transcriptoma , Animais , Ciclo Celular , Linhagem da Célula , Células Precursoras Eritroides/metabolismo , Feminino , Células-Tronco Hematopoéticas/metabolismo , Megacariócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/metabolismo
16.
Life Sci ; 256: 117840, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32450173

RESUMO

AIMS: Platelet production improvement can resolve concerns about the limitations of external platelet supply and platelet transfusion in thrombocytopenia patients. To this end, scientists encourage to induce the generation of megakaryocyte and platelet. Curcumin is a safe ingredient of turmeric that affects various cellular pathways. The effect of this component on platelet production has not been yet reported. MAIN METHODS: Our in vitro experiments include the investigation of the effects of nanocurcumin on megakaryocytes production from K562 cells and hematopoietic stem cells via megakaryocyte markers expression, DNA content, ROS, and morphologic analysis, and CFC assay. The regulatory functions of MAPKs pathways were also determined. In the in vivo study tissue distribution of nanocurcumin was determined and two treatment schedules were used to evaluate the capability of nanocurcumin to prevent the occurrence of Busulfan-induced thrombocytopenia in the mouse model. KEY FINDING: In vitro evidences demonstrated that nanocurcumin can induce MK production from K562 cells and hematopoietic stem cells. Inhibition of ERK1/2 and JNK pathways arrested this activity. In vivo experiments showed the uptake of nanocurcumin by tissues in mice. Administration of nanocurcumin could preserve bone marrow integrity and increase of the number of circulating platelets in the Busulfan-treated mice models. SIGNIFICANCE: Our results have demonstrated that nanocurcumin administration can be useful for the improvement of megakaryocytes and platelet generation in vitro. This component may be exerting these beneficial effects on megakaryopoiesis by modulating ERK1/2 and JNK pathways. As well as nanocurcumin has the potential to prevent thrombocytopenia in chemotherapy threated mice.


Assuntos
Plaquetas/efeitos dos fármacos , Curcumina/farmacologia , Megacariócitos/efeitos dos fármacos , Nanoestruturas , Trombocitopenia/prevenção & controle , Animais , Antineoplásicos Alquilantes/toxicidade , Plaquetas/metabolismo , Bussulfano/toxicidade , Curcumina/administração & dosagem , Curcumina/farmacocinética , Feminino , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Células K562 , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Megacariócitos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Trombocitopenia/induzido quimicamente , Distribuição Tecidual
17.
Mol Cell ; 78(3): 506-521.e6, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32386543

RESUMO

Higher-order chromatin structure and DNA methylation are implicated in multiple developmental processes, but their relationship to cell state is unknown. Here, we find that large (>7.3 kb) DNA methylation nadirs (termed "grand canyons") can form long loops connecting anchor loci that may be dozens of megabases (Mb) apart, as well as inter-chromosomal links. The interacting loci cover a total of ∼3.5 Mb of the human genome. The strongest interactions are associated with repressive marks made by the Polycomb complex and are diminished upon EZH2 inhibitor treatment. The data are suggestive of the formation of these loops by interactions between repressive elements in the loci, forming a genomic subcompartment, rather than by cohesion/CTCF-mediated extrusion. Interestingly, unlike previously characterized subcompartments, these interactions are present only in particular cell types, such as stem and progenitor cells. Our work reveals that H3K27me3-marked large DNA methylation grand canyons represent a set of very-long-range loops associated with cellular identity.


Assuntos
Cromatina/química , Cromatina/genética , Metilação de DNA , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Diferenciação Celular , Cromatina/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigênese Genética , Regulação da Expressão Gênica , Histonas/genética , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Hibridização in Situ Fluorescente , Lisina/genética , Lisina/metabolismo , Proteínas Nucleares/genética , Fatores de Transcrição SOXB1/genética , Proteína de Homoeobox de Baixa Estatura/genética , Fatores de Transcrição/genética
18.
Adv Wound Care (New Rochelle) ; 9(5): 264-276, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32226650

RESUMO

Objective: Epidermal CD34+ stem cells located in the hair follicle (HF) bulge area are capable of inducing HF neogenesis and enhancing wound healing after transplantation. In this study, we observed CD34+ cells derived from blood directly participate in dermal regeneration during full-thickness excisional wound healing. Approach: We isolated and in vitro expanded a subset of hematopoietic stem cell (HSC)-like precursor cells from the peripheral blood of adult mice with the surface markers: CD34+, leucine rich repeat containing G protein-coupled receptor 5 (LGR5)+, CD44+, c-kit+, lineage negative (lin-), and E-cadherin-. These blood-derived precursor cells (BDPCs), can be further differentiated into epithelial-like cells (eBDPCs) and secret fibroblast growth factor 9 (Fgf9) protein. Result: When transplanted into full-thickness skin wounds, eBDPC treatment produced accelerated healing and enhanced skin structure regeneration with less dermal scar formation. Also, HF neogenesis (HFN) was observed with incorporation of labeled BDPCs in the wound area. Innovation:Nondermal-derived CD34+ cells (BDPCs) from the adult unmobilized peripheral blood are capable of in vitro expansion and differentiation.Successful establishment of an in vitro technical platform for BDPCs expansion and differentiation.The in vitro expanded and differentiated epithelial-like cells (eBDPCs) enhance wound healing and directly contribute to skin regeneration and HFN. Conclusion: BDPCs isolated and expanded from adult peripheral blood may provide a possible new cell-based treatment strategy for HF neogenesis and skin wound regeneration.


Assuntos
Folículo Piloso , Transplante de Células-Tronco Hematopoéticas , Regeneração , Pele/patologia , Cicatrização , Animais , Biomarcadores/sangue , Diferenciação Celular , Cicatriz/patologia , Células Epiteliais/metabolismo , Células-Tronco Hematopoéticas/citologia , Masculino , Camundongos
19.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(2): 145-151, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32314712

RESUMO

Objective To construct the hematopoietic microenvironment system simulating different hematopoietic sites during the embryonic stages for in vitro inducing the differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) into hematopoietic cells, and to initially evaluate the efficiency of differentiation. Methods Stereomicroscopy and HE staining were used to observe the anatomical parts and morphology of yolk sac (YS), placenta (PL) and fetal liver (FL) of E11.5 mice. The embryonic YS, PL and FL tissues from the stages of E7.5-E9.5, E10.5-E12.5 and E13.5-E15.5 were collected for stromal cell culture, and conditioned culture media were prepared, namely, yolk sac stromal cell conditioned medium (YSSC-CM), placental SC-CM (PLSC-CM) and fetal liver SC-CM (FLSC-CM), and co-cultured with in vitro expanded SD rat BMSCs. The experimental cells were divided into control group, interleukin 6(IL-6) combined with stem cell factor (SCF) treatment group, YSSC-CM treatment group, PLSC-CM treatment group and FLSC-CM treatment group. After co-culture for 7-9 days, the floating cells in culture medium were collected. Giemsa staining was used to exam cell morphology. Direct immunofluorescence was conducted to detect CD34 and CD45 expression. Colony formation assay was performed to detect granulocyte/macrophage colony formation unit (GM-CFU) to identify differentiated cells. Results Under a stereomicroscope, PL and FL of mouse embryos had the same position as human embryos, while YS was wrapped on the outer side of embryo body and amniotic membrane. HE staining showed that PL vessel labyrinth, FL sinusoids and YS blood islands were rich in blood cells. The inverted phase-contrast microscope and cell counting results indicated that the floating cells in the culture medium of the YSSC-CM group, the PLSC-CM group and the FLSC-CM group significantly increased compared with the control group and the IL-6 combined with SCF group, especially the FLSC-CM group had the most. The floating cells in YSSC-CM group, PLSC-CM group and FLSC-CM group were similar in morphology to lymphoid or mononucleoid cells as showed by Giemsa staining, and expressed hematopoietic cell-specific surface markers CD34 and CD45. The number of hematopoietic cell colonies formed was the most in the FLSC-CM group, followed by the PLSC-CM group, and the least in the YSSC-CM group. The control group and IL-6 combined with SCF treatment group had no changes. Conclusion By collecting YS, PL, and FL according to the stage and time sequence, YSSC-CM, PLSC-CM, and FLSC-CM prepared can induce the differentiation of SD rat's BMSCs into hematopoietic cells, and FLSC-CM-treated cells have better differentiation efficiency.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular , Células-Tronco Hematopoéticas/citologia , Células-Tronco Mesenquimais/citologia , Animais , Células Cultivadas , Embrião de Mamíferos , Feminino , Fígado , Camundongos , Placenta , Gravidez , Ratos , Ratos Sprague-Dawley , Saco Vitelino
20.
Nat Commun ; 11(1): 2042, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341362

RESUMO

The endothelial cell adhesion molecule E-selectin is a key component of the bone marrow hematopoietic stem cell (HSC) vascular niche regulating balance between HSC self-renewal and commitment. We now report in contrast, E-selectin directly triggers signaling pathways that promote malignant cell survival and regeneration. Using acute myeloid leukemia (AML) mouse models, we show AML blasts release inflammatory mediators that upregulate endothelial niche E-selectin expression. Alterations in cell-surface glycosylation associated with oncogenesis enhances AML blast binding to E-selectin and enable promotion of pro-survival signaling through AKT/NF-κB pathways. In vivo AML blasts with highest E-selectin binding potential are 12-fold more likely to survive chemotherapy and main contributors to disease relapse. Absence (in Sele-/- hosts) or therapeutic blockade of E-selectin using small molecule mimetic GMI-1271/Uproleselan effectively inhibits this niche-mediated pro-survival signaling, dampens AML blast regeneration, and strongly synergizes with chemotherapy, doubling the duration of mouse survival over chemotherapy alone, whilst protecting endogenous HSC.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Selectina E/antagonistas & inibidores , Selectina E/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Medula Óssea , Técnicas de Cocultura , Modelos Animais de Doenças , Feminino , Glicolipídeos/uso terapêutico , Glicosilação , Células-Tronco Hematopoéticas/citologia , Humanos , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
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