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1.
Nat Commun ; 11(1): 4034, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32788576

RESUMO

Wiskott-Aldrich syndrome (WAS) is an X-linked primary immunodeficiency with severe platelet abnormalities and complex immunodeficiency. Although clinical gene therapy approaches using lentiviral vectors have produced encouraging results, full immune and platelet reconstitution is not always achieved. Here we show that a CRISPR/Cas9-based genome editing strategy allows the precise correction of WAS mutations in up to 60% of human hematopoietic stem and progenitor cells (HSPCs), without impairing cell viability and differentiation potential. Delivery of the editing reagents to WAS HSPCs led to full rescue of WASp expression and correction of functional defects in myeloid and lymphoid cells. Primary and secondary transplantation of corrected WAS HSPCs into immunodeficient mice showed persistence of edited cells for up to 26 weeks and efficient targeting of long-term repopulating stem cells. Finally, no major genotoxicity was associated with the gene editing process, paving the way for an alternative, yet highly efficient and safe therapy.


Assuntos
Edição de Genes , Terapia Genética , Células-Tronco Hematopoéticas/metabolismo , Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/terapia , Animais , Plaquetas/metabolismo , Sistemas CRISPR-Cas/genética , Linhagem da Célula , Códon/genética , Feminino , Loci Gênicos , Células HEK293 , Transplante de Células-Tronco Hematopoéticas , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Macrófagos/metabolismo , Masculino , Camundongos , Testes de Mutagenicidade , Células Mieloides/metabolismo , Linfócitos T/metabolismo , Síndrome de Wiskott-Aldrich/patologia , Proteína da Síndrome de Wiskott-Aldrich/genética
2.
Nat Commun ; 11(1): 4075, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796847

RESUMO

Hematopoietic ageing involves declining erythropoiesis and lymphopoiesis, leading to frequent anaemia and decreased adaptive immunity. How intrinsic changes to the hematopoietic stem cells (HSCs), an altered microenvironment and systemic factors contribute to this process is not fully understood. Here we use bone marrow stromal cells as sensors of age-associated changes to the bone marrow microenvironment, and observe up-regulation of IL-6 and TGFß signalling-induced gene expression in aged bone marrow stroma. Inhibition of TGFß signalling leads to reversal of age-associated HSC platelet lineage bias, increased generation of lymphoid progenitors and rebalanced HSC lineage output in transplantation assays. In contrast, decreased erythropoiesis is not an intrinsic property of aged HSCs, but associated with decreased levels and functionality of erythroid progenitor populations, defects ameliorated by TGFß-receptor and IL-6 inhibition, respectively. These results show that both HSC-intrinsic and -extrinsic mechanisms are involved in age-associated hematopoietic decline, and identify therapeutic targets that promote their reversal.


Assuntos
Envelhecimento/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Interleucina-6/metabolismo , Células-Tronco Mesenquimais/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Envelhecimento/genética , Animais , Medula Óssea , Ciclo Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Células Precursoras Eritroides , Eritropoese/genética , Eritropoese/fisiologia , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Hematopoese , Interleucina-6/genética , Linfopoese/genética , Linfopoese/fisiologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides , Transdução de Sinais , Nicho de Células-Tronco , Fator de Crescimento Transformador beta1/genética
3.
Nat Commun ; 11(1): 3327, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620863

RESUMO

Gaucher disease is a lysosomal storage disorder caused by insufficient glucocerebrosidase activity. Its hallmark manifestations are attributed to infiltration and inflammation by macrophages. Current therapies for Gaucher disease include life-long intravenous administration of recombinant glucocerebrosidase and orally-available glucosylceramide synthase inhibitors. An alternative approach is to engineer the patient's own hematopoietic system to restore glucocerebrosidase expression, thereby replacing the affected cells, and constituting a potential one-time therapy for this disease. Here, we report an efficient CRISPR/Cas9-based approach that targets glucocerebrosidase expression cassettes with a monocyte/macrophage-specific element to the CCR5 safe-harbor locus in human hematopoietic stem and progenitor cells. The targeted cells generate glucocerebrosidase-expressing macrophages and maintain long-term repopulation and multi-lineage differentiation potential with serial transplantation. The combination of a safe-harbor and a lineage-specific promoter establishes a universal correction strategy and circumvents potential toxicity of ectopic glucocerebrosidase in the stem cells. Furthermore, it constitutes an adaptable platform for other lysosomal enzyme deficiencies.


Assuntos
Edição de Genes/métodos , Glucosilceramidase/metabolismo , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/enzimologia , Macrófagos/enzimologia , Monócitos/enzimologia , Animais , Diferenciação Celular/genética , Células Cultivadas , Doença de Gaucher/genética , Doença de Gaucher/terapia , Glucosilceramidase/genética , Células HEK293 , Hematopoese/genética , Células-Tronco Hematopoéticas/metabolismo , Humanos , Macrófagos/metabolismo , Engenharia Metabólica , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Monócitos/metabolismo , Transplante Autólogo
4.
Nat Commun ; 11(1): 3702, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32710081

RESUMO

Spinal cord injury (SCI) causes immune dysfunction, increasing the risk of infectious morbidity and mortality. Since bone marrow hematopoiesis is essential for proper immune function, we hypothesize that SCI disrupts bone marrow hematopoiesis. Indeed, SCI causes excessive proliferation of bone marrow hematopoietic stem and progenitor cells (HSPC), but these cells cannot leave the bone marrow, even after challenging the host with a potent inflammatory stimulus. Sequestration of HSPCs in bone marrow after SCI is linked to aberrant chemotactic signaling that can be reversed by post-injury injections of Plerixafor (AMD3100), a small molecule inhibitor of CXCR4. Even though Plerixafor liberates HSPCs and mature immune cells from bone marrow, competitive repopulation assays show that the intrinsic long-term functional capacity of HSPCs is still impaired in SCI mice. Together, our data suggest that SCI causes an acquired bone marrow failure syndrome that may contribute to chronic immune dysfunction.


Assuntos
Transtornos da Insuficiência da Medula Óssea/etiologia , Medula Óssea/metabolismo , Traumatismos da Medula Espinal/complicações , Animais , Medula Óssea/patologia , Células da Medula Óssea , Transtornos da Insuficiência da Medula Óssea/patologia , Proliferação de Células , Quimiocina CXCL12 , Modelos Animais de Doenças , Feminino , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Compostos Heterocíclicos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Receptores CXCR4/antagonistas & inibidores , Transdução de Sinais , Traumatismos da Medula Espinal/imunologia
5.
Nat Commun ; 11(1): 3778, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728076

RESUMO

Targeted genome editing has a great therapeutic potential to treat disorders that require protein replacement therapy. To develop a platform independent of specific patient mutations, therapeutic transgenes can be inserted in a safe and highly transcribed locus to maximize protein expression. Here, we describe an ex vivo editing approach to achieve efficient gene targeting in human hematopoietic stem/progenitor cells (HSPCs) and robust expression of clinically relevant proteins by the erythroid lineage. Using CRISPR-Cas9, we integrate different transgenes under the transcriptional control of the endogenous α-globin promoter, recapitulating its high and erythroid-specific expression. Erythroblasts derived from targeted HSPCs secrete different therapeutic proteins, which retain enzymatic activity and cross-correct patients' cells. Moreover, modified HSPCs maintain long-term repopulation and multilineage differentiation potential in transplanted mice. Overall, we establish a safe and versatile CRISPR-Cas9-based HSPC platform for different therapeutic applications, including hemophilia and inherited metabolic disorders.


Assuntos
Engenharia Celular/métodos , Edição de Genes , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/metabolismo , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular , Feminino , Regulação da Expressão Gênica , Hemofilia A/terapia , Humanos , Doenças Metabólicas/terapia , Camundongos , Regiões Promotoras Genéticas/genética , Transplante Autólogo/métodos , Transplante Heterólogo , alfa-Globinas/genética , alfa-Globinas/metabolismo
6.
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
7.
Nat Commun ; 11(1): 3021, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541670

RESUMO

The caudal-related homeobox transcription factor CDX2 is expressed in leukemic cells but not during normal blood formation. Retroviral overexpression of Cdx2 induces AML in mice, however the developmental stage at which CDX2 exerts its effect is unknown. We developed a conditionally inducible Cdx2 mouse model to determine the effects of in vivo, inducible Cdx2 expression in hematopoietic stem and progenitor cells (HSPCs). Cdx2-transgenic mice develop myelodysplastic syndrome with progression to acute leukemia associated with acquisition of additional driver mutations. Cdx2-expressing HSPCs demonstrate enrichment of hematopoietic-specific enhancers associated with pro-differentiation transcription factors. Furthermore, treatment of Cdx2 AML with azacitidine decreases leukemic burden. Extended scheduling of low-dose azacitidine shows greater efficacy in comparison to intermittent higher-dose azacitidine, linked to more specific epigenetic modulation. Conditional Cdx2 expression in HSPCs is an inducible model of de novo leukemic transformation and can be used to optimize treatment in high-risk AML.


Assuntos
Fator de Transcrição CDX2/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Síndromes Mielodisplásicas/metabolismo , Animais , Fator de Transcrição CDX2/genética , Transformação Celular Neoplásica , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/fisiopatologia
8.
Nat Commun ; 11(1): 3150, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561755

RESUMO

MLKL is the essential effector of necroptosis, a form of programmed lytic cell death. We have isolated a mouse strain with a single missense mutation, MlklD139V, that alters the two-helix 'brace' that connects the killer four-helix bundle and regulatory pseudokinase domains. This confers constitutive, RIPK3 independent killing activity to MLKL. Homozygous mutant mice develop lethal postnatal inflammation of the salivary glands and mediastinum. The normal embryonic development of MlklD139V homozygotes until birth, and the absence of any overt phenotype in heterozygotes provides important in vivo precedent for the capacity of cells to clear activated MLKL. These observations offer an important insight into the potential disease-modulating roles of three common human MLKL polymorphisms that encode amino acid substitutions within or adjacent to the brace region. Compound heterozygosity of these variants is found at up to 12-fold the expected frequency in patients that suffer from a pediatric autoinflammatory disease, chronic recurrent multifocal osteomyelitis (CRMO).


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Sistema Hematopoético/patologia , Necroptose/genética , Proteínas Quinases/genética , Animais , Animais Recém-Nascidos , Doenças Hereditárias Autoinflamatórias , Humanos , Inflamação/genética , Camundongos , Mutação de Sentido Incorreto , Osteomielite/genética , Proteínas Quinases/metabolismo
9.
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
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.
Vascular ; 28(5): 664-672, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32390561

RESUMO

BACKGROUND: The high rate of clinical failure of prosthetic arteriovenous grafts continues to suggest the need for novel tissue-engineered vascular grafts. We tested the hypothesis that the decellularized rat jugular vein could be successfully used as a conduit and that it would support reendothelialization as well as adaptation to the arterial environment. MATERIALS AND METHODS: Autologous (control) or heterologous decellularized jugular vein (1 cm length, 1 mm diameter) was sewn between the inferior vena cava and aorta as an arteriovenous graft in Wistar rats. Rats were sacrificed on postoperative day 21 for examination. RESULTS: All rats survived, and grafts had 100% patency in both the control and decellularized groups. Both control and decellularized jugular vein grafts showed similar rates of reendothelialization, smooth muscle cell deposition, macrophage infiltration, and cell turnover. The outflow veins distal to the grafts showed similar adaptation to the arteriovenous flow. Both CD34, CD90 and nestin positive cells, as well as M1-type and M2-type macrophages accumulated around the graft. CONCLUSIONS: This model shows that decellularized vein can be successfully used as an arteriovenous graft between the rat aorta and the inferior vena cava. Several types of cells, including progenitor cells and macrophages, are present in the host response to these grafts in this model. This model can be used to test the application of arteriovenous grafts before conducting large animal experiments.


Assuntos
Aorta/cirurgia , Derivação Arteriovenosa Cirúrgica , Veias Jugulares/transplante , Grau de Desobstrução Vascular , Veia Cava Inferior/cirurgia , Animais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Veias Jugulares/metabolismo , Veias Jugulares/patologia , Veias Jugulares/fisiopatologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Ratos Wistar , Fatores de Tempo , Remodelação Vascular
12.
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
13.
J Cancer Res Ther ; 16(1): 23-27, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32362605

RESUMO

Objective: Growth factor independence 1 (GFI1), a transcriptional repressor, is required for hematopoietic stem cell maintenance and self-renewal in addition to controlling differentiation and proliferation of myeloid cells. As murine studies have demonstrated that this transcription factor has a notable role in the initiation and progression of acute myeloid leukemia (AML) disease, the aim of the current study was to investigate and review the influence of GFI1 in human AML cells. Methods: GFI1 expression levels were measured by means of real-time polymerase chain reaction in 96 primary AML samples which were then compared to gene expression levels observed in 18 healthy subjects. Moreover, GFI1 expression patterns were analyzed based on specific AML subtypes including acute promyelocytic leukemia (APL). Finally, leukemic cells were stained to measure levels of myeloperoxidase (MPO) activity. Results: This study reports that AML patients have significantly higher GFI1 mRNA levels in comparison to healthy subjects and that, when considering AML subtypes, patients with APL have higher GFI1 expression than non-APL patients. Conclusion: It is also concluded that GFI1 overexpression in patients with high MPO levels, such as those of the APL subtype, is correlated with favorable disease prognosis as supported by other studies which demonstrate that increased peroxide activity and GFI1 are independently correlated with a favorable prognosis.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Promielocítica Aguda/metabolismo , Fatores de Transcrição/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Proteínas de Ligação a DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Transcrição/genética , Adulto Jovem
14.
Nat Med ; 26(4): 535-541, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32284612

RESUMO

Base editing by nucleotide deaminases linked to programmable DNA-binding proteins represents a promising approach to permanently remedy blood disorders, although its application in engrafting hematopoietic stem cells (HSCs) remains unexplored. In this study, we purified A3A (N57Q)-BE3 base editor for ribonucleoprotein (RNP) electroporation of human-peripheral-blood-mobilized CD34+ hematopoietic stem and progenitor cells (HSPCs). We observed frequent on-target cytosine base edits at the BCL11A erythroid enhancer at +58 with few indels. Fetal hemoglobin (HbF) induction in erythroid progeny after base editing or nuclease editing was similar. A single therapeutic base edit of the BCL11A enhancer prevented sickling and ameliorated globin chain imbalance in erythroid progeny from sickle cell disease and ß-thalassemia patient-derived HSPCs, respectively. Moreover, efficient multiplex editing could be achieved with combined disruption of the BCL11A erythroid enhancer and correction of the HBB -28A>G promoter mutation. Finally, base edits could be produced in multilineage-repopulating self-renewing human HSCs with high frequency as assayed in primary and secondary recipient animals resulting in potent HbF induction in vivo. Together, these results demonstrate the potential of RNP base editing of human HSPCs as a feasible alternative to nuclease editing for HSC-targeted therapeutic genome modification.


Assuntos
Anemia Falciforme/patologia , Edição de Genes , Terapia Genética/métodos , Células-Tronco Hematopoéticas/metabolismo , Proteínas Repressoras/genética , gama-Globinas/genética , Anemia Falciforme/terapia , Animais , Antígenos CD34/metabolismo , Sistemas CRISPR-Cas , Células Cultivadas , Estudos de Viabilidade , Feminino , Edição de Genes/métodos , Marcação de Genes/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/patologia , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Cultura Primária de Células , Proteínas Repressoras/metabolismo , Talassemia beta/patologia , Talassemia beta/terapia , gama-Globinas/metabolismo
15.
PLoS One ; 15(4): e0229593, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324791

RESUMO

Acute myeloid leukaemia (AML) is characterised by phenotypic heterogeneity, which we hypothesise is a consequence of deregulated differentiation with transcriptional reminiscence of the normal compartment or cell-of-origin. Here, we propose a classification system based on normal myeloid progenitor cell subset-associated gene signatures (MAGS) for individual assignments of AML subtypes. We generated a MAGS classifier including the progenitor compartments CD34+/CD38- for haematopoietic stem cells (HSCs), CD34+/CD38+/CD45RA- for megakaryocyte-erythroid progenitors (MEPs), and CD34+/CD38+/CD45RA+ for granulocytic-monocytic progenitors (GMPs) using regularised multinomial regression with three discrete outcomes and an elastic net penalty. The regularisation parameters were chosen by cross-validation, and MAGS assignment accuracy was validated in an independent data set (N = 38; accuracy = 0.79) of sorted normal myeloid subpopulations. The prognostic value of MAGS assignment was studied in two clinical cohorts (TCGA: N = 171; GSE6891: N = 520) and had a significant prognostic impact. Furthermore, multivariate Cox regression analysis using the MAGS subtype, FAB subtype, cytogenetics, molecular genetics, and age as explanatory variables showed independent prognostic value. Molecular characterisation of subtypes by differential gene expression analysis, gene set enrichment analysis, and mutation patterns indicated reduced proliferation and overrepresentation of RUNX1 and IDH2 mutations in the HSC subtype; increased proliferation and overrepresentation of CEBPA mutations in the MEP subtype; and innate immune activation and overrepresentation of WT1 mutations in the GMP subtype. We present a differentiation-dependent classification system for AML subtypes with distinct pathogenetic and prognostic importance that can help identify candidates poorly responding to combination chemotherapy and potentially guide alternative treatments.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/genética , Células Mieloides/metabolismo , Células-Tronco/metabolismo , ADP-Ribosil Ciclase 1/genética , Antígenos CD34/genética , Diferenciação Celular/genética , Linhagem da Célula/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células-Tronco Hematopoéticas/patologia , Humanos , Isocitrato Desidrogenase/genética , Leucemia Mieloide Aguda/patologia , Antígenos Comuns de Leucócito/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Células Mieloides/patologia , Análise de Componente Principal , Análise de Regressão , Células-Tronco/patologia , Proteínas WT1/genética
16.
Toxicol Appl Pharmacol ; 396: 114996, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278510

RESUMO

Antineoplastic drugs cause severe cytotoxicity for normal cells, especially hematopoietic stem cells (HSCs). However, bleomycin (BLM) is glycopeptide antibiotic that is effective on various cancers and has either low or no myelosuppression effects. The aim of the present study was to investigate the effect of BLM on 5-Azacitidine (5-AZA) induced cytotoxicity in bone marrow HSCs. 5-AZA reduced HSC cell viability in a time and dose-dependent manner with an IC50 value of 16 µM. However, pretreatment of the cells with BLM for 4 h induced an antagonistic cytotoxicity with an increased IC50 of 64 µM. 5-AZA decreased the colony formation ability of HSC cells in semi-solid agar culture and this effect was attenuated by BLM. 5-AZA significantly downregulated high mobility group Box1 (HMGB1) and Bcl-2 gene expression but upregulated Bax gene expression, while BLM impeded the action of 5-AZA. Pretreatment with BLM remarkably decreased HMGB1 release into culture media that was induced by 5-AZA. The cells were distribution at the sub/G1 phase. Annexin/PI staining of the cells, poly (ADP-ribose) polymerase (PARP) cleavage, and anion superoxide production indicated that BLM limited 5-AZA induced apoptotic cell death. In conclusion, BLM in combination with 5-AZA effectively reduces the adverse cytotoxic effects of 5-AZA on bone marrow hematopoietic stem cells, providing a new chemotherapeutic strategy.


Assuntos
Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Azacitidina/toxicidade , Bleomicina/farmacologia , Proteína HMGB1/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo , Animais , Azacitidina/antagonistas & inibidores , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismo
17.
J Pathol ; 251(2): 117-122, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32297672

RESUMO

The intestinal epithelium is perpetually renewed from a stem cell niche in the base of crypts to maintain a healthy bowel mucosa. Exit from this niche and maturation of epithelial cells requires tightly controlled gradients in BMP signalling, progressing from low BMP signalling at the crypt base to high signalling at the luminal surface. The BMP antagonist gremlin 1 (Grem1) is highly expressed by subepithelial myofibroblasts adjacent to the intestinal crypts but its role in regulating the stem cell niche and epithelial renewal in vivo has not been explored. To explore the effects of Grem1 loss in adulthood following normal growth and development, we bred mice (ROSA26CreER-Grem1 flx/flx ) in which Grem1 could be deleted by tamoxifen administration. While Grem1 remained intact, these mice were healthy, grew normally, and reproduced successfully. Following Grem1 depletion, the mice became unwell and were euthanised (at 7-13 days). Post-mortem examination revealed extensive mucosal abnormalities throughout the small and large intestines with failure of epithelial cell replication and maturation, villous atrophy, and features of malabsorption. Bone marrow hypoplasia was also observed with associated early haematopoietic failure. These results demonstrate an essential homeostatic role for gremlin 1 in maintaining normal bowel epithelial function in adulthood, suggesting that abnormalities in gremlin 1 expression can contribute to enteropathies. We also identified a previously unsuspected requirement for gremlin 1 in normal haematopoiesis. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Transtornos da Insuficiência da Medula Óssea/metabolismo , Medula Óssea/metabolismo , Células Epiteliais/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Mucosa Intestinal/metabolismo , Síndromes de Malabsorção/metabolismo , Animais , Medula Óssea/patologia , Transtornos da Insuficiência da Medula Óssea/genética , Transtornos da Insuficiência da Medula Óssea/patologia , Linhagem da Célula , Proliferação de Células , Células Epiteliais/patologia , Hematopoese , Células-Tronco Hematopoéticas/patologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Absorção Intestinal , Mucosa Intestinal/patologia , Síndromes de Malabsorção/genética , Síndromes de Malabsorção/patologia , Masculino , Camundongos Knockout , Fenótipo , Nicho de Células-Tronco
18.
Cell Mol Life Sci ; 77(20): 4031-4047, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32318759

RESUMO

Fate determination in self-renewal and differentiation of hematopoietic stem and progenitor cells (HSCs and HPCs) is ultimately controlled by gene expression, which is profoundly influenced by the global and local chromatin state. Cellular metabolism directly influences the chromatin state through the dynamic regulation of the enzymatic activities that modify DNA and histones, but also generates genotoxic metabolites that can damage DNA and thus pose threat to the genome integrity. On the other hand, mechanisms modulating the chromatin state impact metabolism by regulating the expression and activities of key metabolic enzymes. Moreover, through regulating either DNA damage response directly or expression of genes involved in this process, chromatin modulators play active and crucial roles in guarding the genome integrity, breaching of which results in defective HSPC function. Therefore, HSPC function is regulated by the dynamic and two-way interactions between metabolism and chromatin. Here, we review recent advances that provide a chromatin perspective on the major impacts the metabolic and genotoxic factors can have on HSPC function and fate determination.


Assuntos
Cromatina/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Animais , Diferenciação Celular/fisiologia , Dano ao DNA/fisiologia , Histonas/metabolismo , Humanos
19.
Leukemia ; 34(6): 1512-1523, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32313108

RESUMO

Recent investigations indicate that hematopoiesis is coregulated by innate immunity signals and by pathways characteristic of the activation of innate immunity cells that also operate in normal hematopoietic stem progenitor cells (HSPCs). This should not be surprising because of the common developmental origin of these cells from a hemato/lymphopoietic stem cell. An important integrating factor is the Nlrp3 inflammasome, which has emerged as a major sensor of changes in body microenvironments, cell activation, and cell metabolic activity. It is currently the best-studied member of the inflammasome family expressed in hematopoietic and lymphopoietic cells, including also HSPCs. It is proposed as playing a role in (i) the development and expansion of HSPCs, (ii) their release from bone marrow (BM) into peripheral blood (PB) in stress situations and during pharmacological mobilization, (iii) their homing to BM after transplantation, and (iv) their aging and the regulation of hematopoietic cell metabolism. The Nlrp3 inflammasome is also involved in certain hematological pathologies, including (i) myelodysplastic syndrome, (ii) myeloproliferative neoplasms, (iii) leukemia, and (iv) graft-versus-host disease (GvHD) after transplantation. The aim of this review is to shed more light on this intriguing intracellular protein complex that has become a "rising star" in studies focused on both normal steady-state and pathological hematopoiesis.


Assuntos
Hematopoese/fisiologia , Células-Tronco Hematopoéticas/metabolismo , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Humanos , Síndromes Mielodisplásicas/metabolismo
20.
Nat Commun ; 11(1): 1792, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286289

RESUMO

Continuous cancer growth is driven by subsets of self-renewing malignant cells. Targeting of uncontrolled self-renewal through inhibition of stem cell-related signaling pathways has proven challenging. Here, we show that cancer cells can be selectively deprived of self-renewal ability by interfering with their epigenetic state. Re-expression of histone H1.0, a tumor-suppressive factor that inhibits cancer cell self-renewal in many cancer types, can be broadly induced by the clinically well-tolerated compound Quisinostat. Through H1.0, Quisinostat inhibits cancer cell self-renewal and halts tumor maintenance without affecting normal stem cell function. Quisinostat also hinders expansion of cells surviving targeted therapy, independently of the cancer types and the resistance mechanism, and inhibits disease relapse in mouse models of lung cancer. Our results identify H1.0 as a major mediator of Quisinostat's antitumor effect and suggest that sequential administration of targeted therapy and Quisinostat may be a broadly applicable strategy to induce a prolonged response in patients.


Assuntos
Autorrenovação Celular , Histonas/metabolismo , Ácidos Hidroxâmicos/farmacologia , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Autorrenovação Celular/efeitos dos fármacos , Autorrenovação Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Humanos , Camundongos , Neoplasias/genética , Recidiva
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