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1.
Nature ; 571(7765): 355-360, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31270458

RESUMO

Defining the transcriptomic identity of malignant cells is challenging in the absence of surface markers that distinguish cancer clones from one another, or from admixed non-neoplastic cells. To address this challenge, here we developed Genotyping of Transcriptomes (GoT), a method to integrate genotyping with high-throughput droplet-based single-cell RNA sequencing. We apply GoT to profile 38,290 CD34+ cells from patients with CALR-mutated myeloproliferative neoplasms to study how somatic mutations corrupt the complex process of human haematopoiesis. High-resolution mapping of malignant versus normal haematopoietic progenitors revealed an increasing fitness advantage with myeloid differentiation of cells with mutated CALR. We identified the unfolded protein response as a predominant outcome of CALR mutations, with a considerable dependency on cell identity, as well as upregulation of the NF-κB pathway specifically in uncommitted stem cells. We further extended the GoT toolkit to genotype multiple targets and loci that are distant from transcript ends. Together, these findings reveal that the transcriptional output of somatic mutations in myeloproliferative neoplasms is dependent on the native cell identity.


Assuntos
Genótipo , Mutação , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Neoplasias/genética , Neoplasias/patologia , Transcriptoma/genética , Animais , Antígenos CD34/metabolismo , Calreticulina/genética , Linhagem Celular , Proliferação de Células , Células Clonais/classificação , Células Clonais/metabolismo , Células Clonais/patologia , Endorribonucleases/metabolismo , Hematopoese/genética , Células-Tronco Hematopoéticas/classificação , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Camundongos , Modelos Moleculares , Transtornos Mieloproliferativos/classificação , NF-kappa B/metabolismo , Neoplasias/classificação , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Mielofibrose Primária/genética , Mielofibrose Primária/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Resposta a Proteínas não Dobradas/genética
2.
Nat Biotechnol ; 37(7): 810-818, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31267104

RESUMO

A major challenge for stem cell engineering is achieving a holistic understanding of the molecular networks and biological processes governing cell differentiation. To address this challenge, we describe a computational approach that combines gene expression analysis, previous knowledge from proteomic pathway informatics and cell signaling models to delineate key transitional states of differentiating cells at high resolution. Our network models connect sparse gene signatures with corresponding, yet disparate, biological processes to uncover molecular mechanisms governing cell fate transitions. This approach builds on our earlier CellNet and recent trajectory-defining algorithms, as illustrated by our analysis of hematopoietic specification along the erythroid lineage, which reveals a role for the EGF receptor family member, ErbB4, as an important mediator of blood development. We experimentally validate this prediction and perturb the pathway to improve erythroid maturation from human pluripotent stem cells. These results exploit an integrative systems perspective to identify new regulatory processes and nodes useful in cell engineering.


Assuntos
Engenharia Celular , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Pluripotentes Induzidas/fisiologia , Biologia de Sistemas/métodos , Algoritmos , Animais , Antígenos CD34/genética , Antígenos CD34/metabolismo , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Biologia Computacional/métodos , Eritrócitos , Eritropoese , Citometria de Fluxo , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Camundongos , Receptor ErbB-4/metabolismo , Transdução de Sinais , Peixe-Zebra
3.
Ann Hematol ; 98(9): 2063-2072, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31312928

RESUMO

Rigosertib is a novel multi-kinase inhibitor, which has clinical activity towards leukemic progenitor cells of patients with high-risk myelodysplastic syndromes (MDS) after failure or progression on hypomethylating agents. Since the bone marrow microenvironment plays an important role in MDS pathogenesis, we investigated the impact of rigosertib on cellular compartments within the osteo-hematopoietic niche. Healthy C57BL/6J mice treated with rigosertib for 3 weeks showed a mild suppression of hematopoiesis (hemoglobin and red blood cells, both - 16%, p < 0.01; white blood cells, - 34%, p < 0.05; platelets, - 38%, p < 0.05), whereas there was no difference in the number of hematopoietic stem cells in the bone marrow. Trabecular bone mass of the spine was reduced by rigosertib (- 16%, p = 0.05). This was accompanied by a lower trabecular number and thickness (- 6% and - 10%, respectively, p < 0.05), partly explained by the increase in osteoclast number and surface (p < 0.01). Milder effects of rigosertib on bone mass were detected in an MDS mouse model system (NHD13). However, rigosertib did not further aggravate MDS-associated cytopenia in NHD13 mice. Finally, we tested the effects of rigosertib on human mesenchymal stromal cells (MSC) in vitro and demonstrated reduced cell viability at nanomolar concentrations. Deterioration of the hematopoietic supportive capacity of MDS-MSC after rigosertib pretreatment demonstrated by decreased number of colony-forming units, especially in the monocytic lineage, further supports the idea of disturbed crosstalk within the osteo-hematopoietic niche mediated by rigosertib. Thus, rigosertib exerts inhibitory effects on the stromal components of the osteo-hematopoietic niche which may explain the dissociation between anti-leukemic activity and the absence of hematological improvement.


Assuntos
Glicina/análogos & derivados , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Síndromes Mielodisplásicas , Nicho de Células-Tronco/efeitos dos fármacos , Sulfonas/farmacologia , Animais , Glicina/farmacologia , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Transgênicos , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia
4.
Adv Exp Med Biol ; 1143: 59-74, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31338815

RESUMO

One of the bottlenecks of the treatments for malignant hematopoietic disorders is the unavailability of sufficient amount of hematopoietic stem cells (HSCs). HSCs are considered to be originated from the aorta-gonad-mesonephros and gradually migrates into fetal liver and resides in a unique microenvironment/niche of bone marrow. Although many intrinsic and extrinsic factors (niche components) are reported to be involved in the origination, maturation, migration, and localization of HSCs at different developmental stages, the detailed molecular mechanisms still remain largely unknown. Previous studies have shown that intrinsic metabolic networks may be critical for the cell fate determinations of HSCs. For example, HSCs mainly utilize glycolysis as the main energy sources; oxidative phosphorylation is required for the homeostasis of HSCs; lipid or amino acid metabolisms may also sustain HSC stemness. Mechanistically, lots of regulatory pathways, such as MEIS1/HIF1A and PI3K/AKT/mTOR signaling, are found to fine-tune the different nutrient metabolisms and cell fate commitments of HSCs. However, more efforts are required for the optimization and establishment of precise metabolic techniques specific for the HSCs with relatively rare cell frequency and understanding of the basic metabolic properties and their underlying regulatory mechanisms of different nutrients (such as glucose) during the different developmental stages of HSCs.


Assuntos
Diferenciação Celular , Células-Tronco Hematopoéticas , Transdução de Sinais , Medula Óssea/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos
5.
Immunity ; 50(6): 1439-1452.e5, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31178352

RESUMO

Hematopoietic stem cells (HSCs) are generated from specialized endothelial cells of the embryonic aorta. Inflammatory factors are implicated in regulating mouse HSC development, but which cells in the aorta-gonad-mesonephros (AGM) microenvironment produce these factors is unknown. In the adult, macrophages play both pro- and anti-inflammatory roles. We sought to examine whether macrophages or other hematopoietic cells found in the embryo prior to HSC generation were involved in the AGM HSC-generative microenvironment. CyTOF analysis of CD45+ AGM cells revealed predominance of two hematopoietic cell types, mannose-receptor positive macrophages and mannose-receptor negative myeloid cells. We show here that macrophage appearance in the AGM was dependent on the chemokine receptor Cx3cr1. These macrophages expressed a pro-inflammatory signature, localized to the aorta, and dynamically interacted with nascent and emerging intra-aortic hematopoietic cells (IAHCs). Importantly, upon macrophage depletion, no adult-repopulating HSCs were detected, thus implicating a role for pro-inflammatory AGM-associated macrophages in regulating the development of HSCs.


Assuntos
Diferenciação Celular , Desenvolvimento Embrionário , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Macrófagos/metabolismo , Animais , Biomarcadores , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Imunofluorescência , Imunofenotipagem , Inflamação/etiologia , Inflamação/metabolismo , Macrófagos/citologia , Macrófagos/imunologia , Camundongos , Camundongos Transgênicos , Células Mieloides/citologia , Células Mieloides/metabolismo
6.
Nat Commun ; 10(1): 2891, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253791

RESUMO

Our ability to manage acute myeloid leukemia (AML) is limited by our incomplete understanding of the epigenetic disruption central to leukemogenesis, including improper histone methylation. Here we examine 16 histone H3 genes in 434 primary AML samples and identify Q69H, A26P, R2Q, R8H and K27M/I mutations (1.6%), with higher incidence in secondary AML (9%). These mutations occur in pre-leukemic hematopoietic stem cells (HSCs) and exist in the major leukemic clones in patients. They increase the frequency of functional HSCs, alter differentiation, and amplify leukemic aggressiveness. These effects are dependent on the specific mutation. H3K27 mutation increases the expression of genes involved in erythrocyte and myeloid differentiation with altered H3K27 tri-methylation and K27 acetylation. The functional impact of histone mutations is independent of RUNX1 mutation, although they at times co-occur. This study establishes that H3 mutations are drivers of human pre-cancerous stem cell expansion and important early events in leukemogenesis.


Assuntos
Epigenômica , Regulação Leucêmica da Expressão Gênica/fisiologia , Histonas/metabolismo , Leucemia Mieloide Aguda/metabolismo , Animais , Animais Geneticamente Modificados , Antineoplásicos/farmacologia , Sequência de Bases , Células da Medula Óssea , Diferenciação Celular , Transformação Celular Neoplásica , DNA/genética , Drosophila melanogaster/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Camundongos , Mutação , Neoplasias Experimentais
7.
Nat Commun ; 10(1): 2395, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160568

RESUMO

Hematopoietic Stem/Progenitor cells (HSPCs) are endowed with the role of maintaining a diverse pool of blood cells throughout the human life. Despite recent efforts, the nature of the early cell fate decisions remains contentious. Using single-cell RNA-Seq, we show that existing approaches to stratify bone marrow CD34+ cells reveal a hierarchically-structured transcriptional landscape of hematopoietic differentiation. Still, this landscape misses important early fate decisions. We here provide a broader transcriptional profiling of bone marrow lineage negative hematopoietic progenitors that recovers a key missing branchpoint into basophils and expands our understanding of the underlying structure of early adult human haematopoiesis. We also show that this map has strong similarities in topology and gene expression to that found in mouse. Finally, we identify the sialomucin CD164, as a reliable marker for the earliest branches of HSPCs specification and we showed how its use can foster the design of alternative transplantation cell products.


Assuntos
Hematopoese/genética , Células-Tronco Hematopoéticas/metabolismo , Animais , Antígenos CD34/metabolismo , Células da Medula Óssea , Linhagem da Célula , Endolina/metabolismo , Perfilação da Expressão Gênica , Humanos , Camundongos , Análise de Sequência de RNA , Análise de Célula Única
8.
Gene ; 710: 265-272, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31200085

RESUMO

Patients with leukocyte adhesion deficiency type 1 (LAD1) suffer from life-threatening bacterial infections due to mutations in the common ß2 integrin subunit (CD18/ITGB2 gene). We tested different fragments of the ubiquitous chromatin opening element (UCOE) from the human HNRPA2B1-CBX3 locus for their efficiency in driving the human CD18 gene expression and compared it with that of an elongation factor 1 alpha promoter (EF1αL, 1169 bp; EF1αS 248 bp) and a murine stem cell virus (MSCV) promoter within the context of the same lentiviral vector backbone. These vectors were tested in vitro for the human CD18 gene expression on the surface of CD34+ hematopoietic stem cells (HSCs) isolated from both moderate and severe LAD1 patients. Among the promoters tested in the patients' CD34+ HSCs, only U631 bp, U652 bp, U1262 bp, 5' 2.2 kb A2UCOE and EF1αS resulted in higher percentage of CD18+CD34+ cells comparable to that of the MSCV promoter. The U655 bp, U723 bp, U1296 bp, U2598 bp and EF1αL promoters resulted in comparatively lower numbers of CD18+CD34+ cells. This study would be useful in investigating the human CD18 gene expression in an ex vivo experiment to demonstrate the phenotypic correction of LAD1 in a pre-clinical model.


Assuntos
Antígenos CD18/genética , Proteínas Cromossômicas não Histona/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Lentivirus/genética , Síndrome da Aderência Leucocítica Deficitária/genética , Fator 1 de Elongação de Peptídeos/genética , Terapia Genética , Vetores Genéticos/genética , Células HEK293 , Células-Tronco Hematopoéticas/metabolismo , Humanos , Síndrome da Aderência Leucocítica Deficitária/terapia , Regiões Promotoras Genéticas , Elementos Reguladores de Transcrição , Transdução Genética
9.
Nat Cell Biol ; 21(6): 700-709, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31061465

RESUMO

Haematopoietic stem cells (HSCs) maintain balanced self-renewal and differentiation, but how these functions are precisely regulated is not fully understood. N6-methyladenosine (m6A) messenger RNA methylation has emerged as an important mode of epitranscriptional gene expression regulation affecting many biological processes. We show that deletion of the m6A methyltransferase Mettl3 from the adult haematopoietic system led to an accumulation of HSCs in the bone marrow and a marked reduction of reconstitution potential due to a blockage of HSC differentiation. Interestingly, deleting Mettl3 from myeloid cells using Lysm-cre did not impact myeloid cell number or function. RNA sequencing revealed 2,073 genes with significant m6A modifications in HSCs. Myc was identified as a direct target of m6A in HSCs. Mettl3-deficient HSCs failed to upregulate MYC expression following stimulation to differentiate and enforced expression of Myc rescued differentiation defects of Mettl3-deficient HSCs. Our results reveal a key role of m6A in governing HSC differentiation.


Assuntos
Adenosina/análogos & derivados , Diferenciação Celular/genética , Células-Tronco Hematopoéticas/citologia , Metiltransferases/genética , Proteínas Proto-Oncogênicas c-myc/genética , Adenosina/genética , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Células-Tronco Hematopoéticas/metabolismo , Metilação , Camundongos , RNA Mensageiro/genética , Análise de Sequência de RNA
10.
Nat Cell Biol ; 21(5): 560-567, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30988422

RESUMO

Haematopoietic stem cells (HSCs) are maintained by bone marrow niches in vivo1,2, but the ability of niche cells to maintain HSCs ex vivo is markedly diminished. Expression of niche factors by Nestin-GFP+ mesenchymal-derived stromal cells (MSCs) is downregulated upon culture, suggesting that transcriptional rewiring may contribute to this reduced HSC maintenance potential. Using an RNA sequencing screen, we identified five genes encoding transcription factors (Klf7, Ostf1, Xbp1, Irf3 and Irf7) that restored HSC niche function in cultured bone marrow-derived MSCs. These revitalized MSCs (rMSCs) exhibited enhanced synthesis of HSC niche factors while retaining their mesenchymal differentiation capacity. In contrast to HSCs co-cultured with control MSCs, HSCs expanded with rMSCs showed higher repopulation capacity and protected lethally irradiated recipient mice. Competitive reconstitution assays revealed an approximately sevenfold expansion of functional HSCs by rMSCs. rMSCs prevented the accumulation of DNA damage in cultured HSCs, a hallmark of ageing and replication stress. Analysis of the reprogramming mechanisms uncovered a role for myocyte enhancer factor 2c (Mef2c) in the revitalization of MSCs. These results provide insight into the transcriptional regulation of the niche with implications for stem cell-based therapies.


Assuntos
Diferenciação Celular/genética , Engenharia Celular/métodos , Células-Tronco Hematopoéticas/citologia , Nicho de Células-Tronco/genética , Animais , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Regulação da Expressão Gênica/genética , Células-Tronco Hematopoéticas/metabolismo , Humanos , Fator Regulador 3 de Interferon/genética , Fatores de Transcrição Kruppel-Like/genética , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Transgênicos , Nestina/genética , Peptídeos/genética , Análise de Sequência de RNA/métodos , Proteína 1 de Ligação a X-Box/genética
11.
Int J Mol Sci ; 20(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027199

RESUMO

Preeclampsia (PE) has been associated with placental dysfunction, resulting in fetal hypoxia, accelerated erythropoiesis, and increased erythroblast count in the umbilical cord blood (UCB). Although the detailed effects remain unknown, placental dysfunction can also cause inflammation, nutritional, and oxidative stress in the fetus that can affect erythropoiesis. Here, we compared the expression of surface adhesion molecules and the erythroid differentiation capacity of UCB hematopoietic stem/progenitor cells (HSPCs), UCB erythroid profiles along with the transcriptome and proteome of these cells between male and female fetuses from PE and normotensive pregnancies. While no significant differences were observed in UCB HSPC migration/homing and in vitro erythroid colony differentiation, the UCB HSPC transcriptome and the proteomic profile of the in vitro differentiated erythroid cells differed between PE vs. normotensive samples. Accordingly, despite the absence of significant differences in the UCB erythroid populations in male or female fetuses from PE or normotensive pregnancies, transcriptional changes were observed during erythropoiesis, particularly affecting male fetuses. Pathway analysis suggested deregulation in the mammalian target of rapamycin complex 1/AMP-activated protein kinase (mTORC1/AMPK) signaling pathways controlling cell cycle, differentiation, and protein synthesis. These results associate PE with transcriptional and proteomic changes in fetal HSPCs and erythroid cells that may underlie the higher erythroblast count in the UCB in PE.


Assuntos
Células Eritroides/metabolismo , Feto/patologia , Pré-Eclâmpsia/genética , Proteômica , Caracteres Sexuais , Transcrição Genética , Diferenciação Celular/genética , Movimento Celular/genética , Eritropoese/genética , Feminino , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Humanos , Masculino , Pré-Eclâmpsia/patologia , Gravidez , Resultado da Gravidez/genética , Biossíntese de Proteínas , Transcriptoma/genética , Cordão Umbilical/patologia
12.
Biomed Pharmacother ; 114: 108806, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30928804

RESUMO

Agents that provide protection against irradiation-induced hematopoietic injury are urgently needed for radiotherapy. We examined the effects of the small molecule, 1,2-propanediol (PPD), on total body irradiation (TBI)-induced hematopoietic injury in C57BL/6 mice. PPD administration 1 h before TBI significantly increased hematopoietic parameters such as white blood cell, platelet, red blood cell, and lymphocyte counts in vivo and enhanced the survival of mice exposed to TBI (7.0 and 7.5 Gy). PPD administration 1 h before TBI improved bone marrow (BM) and spleen recovery after TBI, with increases in both BM cellularity and spleen index. The number of colony-forming-units in bone marrow mononuclear cells (BMNCs) in vitro also increased significantly. PPD pretreatment increased the numbers of hematopoietic stem cells and hematopoietic progenitor cells in BM. Importantly, PPD also maintained endogenous antioxidant status by decreasing levels of malondialdehyde and increasing the expression of reduced glutathione, superoxide dismutase and catalase in the serum of irradiated mice. PPD alleviated the levels of apoptosis in HSCs induced by TBI, thus increasing the proportion of dividing BMNCs. These results suggest that PPD protects against TBI-induced hematopoietic injury through the increased activities of antioxidant enzymes and the inhibition of apoptosis in HSCs. PPD increased the serum levels of granulocyte-colony stimulating factor and interleukin-6 irrespective of TBI. In conclusion, these data suggest that PPD acts as a radioprotector against radiation-induced hematopoietic injury.


Assuntos
Células-Tronco Hematopoéticas/efeitos dos fármacos , Propilenoglicol/farmacologia , Lesões Experimentais por Radiação/tratamento farmacológico , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Medula Óssea/metabolismo , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Ensaio de Unidades Formadoras de Colônias/métodos , Fator Estimulador de Colônias de Granulócitos/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Irradiação Corporal Total/métodos
13.
Int J Mol Sci ; 20(7)2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30965622

RESUMO

Although human pluripotent stem cells (hPSCs) can theoretically differentiate into any cell type, their ability to produce hematopoietic cells is highly variable from one cell line to another. The underlying mechanisms of this heterogeneity are not clearly understood. Here, using a whole miRNome analysis approach in hPSCs, we discovered that their hematopoietic competency was associated with the expression of several miRNAs and conversely correlated to that of miR-206 specifically. Lentiviral-based miR-206 ectopic expression in H1 hematopoietic competent embryonic stem (ES) cells markedly impaired their differentiation toward the blood lineage. Integrative bioinformatics identified a potential miR-206 target gene network which included hematopoietic master regulators RUNX1 and TAL1. This work sheds light on the critical role of miR-206 in the generation of blood cells off hPSCs. Our results pave the way for future genetic manipulation of hPSCs aimed at increasing their blood regenerative potential and designing better protocols for the generation of bona fide hPSC-derived hematopoietic stem cells.


Assuntos
MicroRNAs/metabolismo , Células-Tronco Pluripotentes/citologia , Diferenciação Celular/fisiologia , Linhagem Celular , Linhagem da Célula , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Células-Tronco Pluripotentes/metabolismo
14.
Lancet Haematol ; 6(5): e239-e253, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30981783

RESUMO

BACKGROUND: Wiskott-Aldrich syndrome is a rare, life-threatening, X-linked primary immunodeficiency characterised by microthrombocytopenia, infections, eczema, autoimmunity, and malignant disease. Lentiviral vector-mediated haemopoietic stem/progenitor cell (HSPC) gene therapy is a potentially curative treatment that represents an alternative to allogeneic HSPC transplantation. Here, we report safety and efficacy data from an interim analysis of patients with severe Wiskott-Aldrich syndrome who received lentiviral vector-derived gene therapy. METHODS: We did a non-randomised, open-label, phase 1/2 clinical study in paediatric patients with severe Wiskott-Aldrich syndrome, defined by either WAS gene mutation or absent Wiskott-Aldrich syndrome protein (WASP) expression or a Zhu clinical score of 3 or higher. We included patients who had no HLA-identical sibling donor available or, for children younger than 5 years of age, no suitable 10/10 matched unrelated donor or 6/6 unrelated cord blood donor. After treatment with rituximab and a reduced-intensity conditioning regimen of busulfan and fludarabine, patients received one intravenous infusion of autologous CD34+ cells genetically modified with a lentiviral vector encoding for human WAS cDNA. The primary safety endpoints were safety of the conditioning regimen and safety of lentiviral gene transfer into HSPCs. The primary efficacy endpoints were overall survival, sustained engraftment of genetically corrected HSPCs, expression of vector-derived WASP, improved T-cell function, antigen-specific responses to vaccinations, and improved platelet count and mean platelet volume normalisation. This interim analysis was done when the first six patients treated had completed at least 3 years of follow-up. The planned analyses are presented for the intention-to-treat population. This trial is registered with ClinicalTrials.gov (number NCT01515462) and EudraCT (number 2009-017346-32). FINDINGS: Between April 20, 2010, and Feb 26, 2015, nine patients (all male) were enrolled of whom one was excluded after screening; the age range of the eight treated children was 1·1-12·4 years. At the time of the interim analysis (data cutoff April 29, 2016), median follow-up was 3·6 years (range 0·5-5·6). Overall survival was 100%. Engraftment of genetically corrected HSPCs was successful and sustained in all patients. The fraction of WASP-positive lymphocytes increased from a median of 3·9% (range 1·8-35·6) before gene therapy to 66·7% (55·7-98·6) at 12 months after gene therapy, whereas WASP-positive platelets increased from 19·1% (range 4·1-31·0) to 76·6% (53·1-98·4). Improvement of immune function was shown by normalisation of in-vitro T-cell function and successful discontinuation of immunoglobulin supplementation in seven patients with follow-up longer than 1 year, followed by positive antigen-specific response to vaccination. Severe infections fell from 2·38 (95% CI 1·44-3·72) per patient-year of observation (PYO) in the year before gene therapy to 0·31 (0·04-1·11) per PYO in the second year after gene therapy and 0·17 (0·00-0·93) per PYO in the third year after gene therapy. Before gene therapy, platelet counts were lower than 20 × 109 per L in seven of eight patients. At the last follow-up visit, the platelet count had increased to 20-50 × 109 per L in one patient, 50-100 × 109 per L in five patients, and more than 100 × 109 per L in two patients, which resulted in independence from platelet transfusions and absence of severe bleeding events. 27 serious adverse events in six patients occurred after gene therapy, 23 (85%) of which were infectious (pyrexia [five events in three patients], device-related infections, including one case of sepsis [four events in three patients], and gastroenteritis, including one case due to rotavirus [three events in two patients]); these occurred mainly in the first 6 months of follow-up. No adverse reactions to the investigational drug product and no abnormal clonal proliferation or leukaemia were reported after gene therapy. INTERPRETATION: Data from this study show that gene therapy provides a valuable treatment option for patients with severe Wiskott-Aldrich syndrome, particularly for those who do not have a suitable HSPC donor available. FUNDING: Italian Telethon Foundation, GlaxoSmithKline, and Orchard Therapeutics.


Assuntos
Terapia Genética , Vetores Genéticos/genética , Células-Tronco Hematopoéticas/metabolismo , Lentivirus/genética , Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/terapia , Criança , Pré-Escolar , Feminino , Terapia Genética/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Lactente , Itália , Masculino , Mutação , Linfócitos T/imunologia , Linfócitos T/metabolismo , Condicionamento Pré-Transplante/métodos , Resultado do Tratamento , Síndrome de Wiskott-Aldrich/sangue , Síndrome de Wiskott-Aldrich/diagnóstico , Proteína da Síndrome de Wiskott-Aldrich/genética
15.
Best Pract Res Clin Haematol ; 32(1): 13-23, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30927970

RESUMO

Clonal Hematopoiesis is defined as the presence of mutations in peripheral blood in the absence of myeloid malignancies and is thought to occur as a normal part of ageing due to the fitness advantage conferred by these mutations in an ageing hematopoietic compartment. Therapy related myeloid neoplasms are malignancies that occur after exposure to chemotherapy/radiation and are associated with poor survival. Clonal hematopoiesis mutations represent a pre malignant state that can be triggered by exposure to cytotoxic damage and rapid hematopoietic stem cell expansion. We discuss in this review clinical evidence of association of clonal hematopoiesis with risk of therapy related myeloid neoplasms, the underlying mechanisms of clonal expansion under different cellular stresses and recommendations on clinical follow up of patients with clonal hematopoiesis including possible strategies for prevention of therapy related myeloid neoplasms.


Assuntos
Hematopoese/genética , Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Mutação , Síndromes Mielodisplásicas , Segunda Neoplasia Primária , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/terapia , Segunda Neoplasia Primária/genética , Segunda Neoplasia Primária/metabolismo , Segunda Neoplasia Primária/patologia , Segunda Neoplasia Primária/terapia
16.
Best Pract Res Clin Haematol ; 32(1): 31-39, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30927973

RESUMO

Therapy-related myeloid neoplasms are unintended and unwanted complications of cytotoxic chemotherapy and radiation. Unlike other environmental toxin-induced malignancies, exposure to the inciting agent is required to eradicate a primary and life-threatening cancer. In this review, we will focus on the biochemical mechanisms that lead to therapy-induced myeloid malignancy. This includes discussion of known mechanisms by which cytotoxic chemotherapy and radiation induce genetic mutations and promote evolution and expansion of malignant hematopoietic clones. Mechanisms by which the hematopoietic stem and progenitor microenvironment may be injured during the course of chemotherapy and radiation therapy will also be presented. While prevention strategies have not yet been brought into clinical testing or practice, there is active basic research relevant to prevention of t-MNs which is also included in our attempt to answer the question of whether we can do better to prevent stem cell injury after chemotherapy and radiation.


Assuntos
Neoplasias Hematológicas , Células-Tronco Hematopoéticas , Mutação , Transtornos Mieloproliferativos , Nicho de Células-Tronco , Microambiente Tumoral , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patologia , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Segunda Neoplasia Primária/genética , Segunda Neoplasia Primária/metabolismo , Segunda Neoplasia Primária/patologia , Radioterapia/efeitos adversos , Nicho de Células-Tronco/efeitos dos fármacos , Nicho de Células-Tronco/genética , Nicho de Células-Tronco/efeitos da radiação , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/efeitos da radiação
17.
Nat Commun ; 10(1): 1634, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30967552

RESUMO

Gene correction in human long-term hematopoietic stem cells (LT-HSCs) could be an effective therapy for monogenic diseases of the blood and immune system. Here we describe an approach for X-linked sSevere cCombined iImmunodeficiency (SCID-X1) using targeted integration of a cDNA into the endogenous start codon to functionally correct disease-causing mutations throughout the gene. Using a CRISPR-Cas9/AAV6 based strategy, we achieve up to 20% targeted integration frequencies in LT-HSCs. As measures of the lack of toxicity we observe no evidence of abnormal hematopoiesis following transplantation and no evidence of off-target mutations using a high-fidelity Cas9 as a ribonucleoprotein complex. We achieve high levels of targeting frequencies (median 45%) in CD34+ HSPCs from six SCID-X1 patients and demonstrate rescue of lymphopoietic defect in a patient derived HSPC population in vitro and in vivo. In sum, our study provides specificity, toxicity and efficacy data supportive of clinical development of genome editing to treat SCID-Xl.


Assuntos
DNA Complementar/genética , Edição de Genes/métodos , Transplante de Células-Tronco Hematopoéticas , Subunidade gama Comum de Receptores de Interleucina/genética , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/terapia , Animais , Antígenos CD34/metabolismo , Sistemas CRISPR-Cas/genética , Linhagem Celular , Códon de Iniciação/genética , Éxons/genética , Sangue Fetal/citologia , Vetores Genéticos/genética , Voluntários Saudáveis , Células-Tronco Hematopoéticas/metabolismo , Humanos , Masculino , Camundongos , Mutação , Parvovirinae/genética , Cultura Primária de Células , Fatores de Tempo , Transdução Genética/métodos , Quimeras de Transplante/genética , Transplante Heterólogo/métodos , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/genética
18.
Nat Commun ; 10(1): 1903, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015418

RESUMO

Single-cell transcriptomic assays have enabled the de novo reconstruction of lineage differentiation trajectories, along with the characterization of cellular heterogeneity and state transitions. Several methods have been developed for reconstructing developmental trajectories from single-cell transcriptomic data, but efforts on analyzing single-cell epigenomic data and on trajectory visualization remain limited. Here we present STREAM, an interactive pipeline capable of disentangling and visualizing complex branching trajectories from both single-cell transcriptomic and epigenomic data. We have tested STREAM on several synthetic and real datasets generated with different single-cell technologies. We further demonstrate its utility for understanding myoblast differentiation and disentangling known heterogeneity in hematopoiesis for different organisms. STREAM is an open-source software package.


Assuntos
Algoritmos , Linhagem da Célula/genética , Genômica/métodos , Células-Tronco Hematopoéticas/metabolismo , Análise de Célula Única/estatística & dados numéricos , Transcriptoma , Animais , Diferenciação Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células Eritroides/citologia , Células Eritroides/metabolismo , Fator de Transcrição GATA1/genética , Fator de Transcrição GATA1/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Hematopoéticas/citologia , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Linfócitos/citologia , Linfócitos/metabolismo , Camundongos , Redução Dimensional com Múltiplos Fatores , Células Mieloides/citologia , Células Mieloides/metabolismo , Mioblastos/citologia , Mioblastos/metabolismo , Transdução de Sinais , Análise de Célula Única/métodos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Int J Mol Sci ; 20(7)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30978983

RESUMO

The bone marrow (BM) microenvironment plays a crucial role in the maintenance and regeneration of hematopoietic stem (HSC) and progenitor cells (HSPC). In particular, the vascular niche is responsible for regulating HSC maintenance, differentiation, and migration of cells in and out of the BM. Damage to this niche upon exposure to ionizing radiation, whether accidental or as a result of therapy, can contribute to delays in HSC recovery and/or function. The ability of BM derived-endothelial cells (BMEC) to alter and/or protect HSPC after exposure to ionizing radiation was investigated. Our data show that exposure of BMEC to ionizing radiation resulted in alterations in Akt signaling, increased expression of PARP-1, IL6, and MCP-1, and decreased expression of MMP1 and MMP9. In addition, global analysis of gene expression of HSC and BMEC in response to mixed neutron/gamma field (MF) radiation identified 60 genes whose expression was altered after radiation in both cell types, suggesting that a subset of genes is commonly affected by this type of radiation. Focused gene analysis by RT-PCR revealed two categories of BMEC alterations: (a) a subset of genes whose expression was altered in response to radiation, with no additional effect observed during coculture with HSPC, and (b) a subset of genes upregulated in response to radiation, and altered when cocultured with HSPC. Coculture of BMEC with CD34+ HSPC induced HSPC proliferation, and improved BM function after MF radiation. Nonirradiated HSPC exhibited reduced CD34 expression over time, but when irradiated, they maintained higher CD34 expression. Nonirradiated HSPC cocultured with nonirradiated BMEC expressed lower levels of CD34 expression compared to nonirradiated alone. These data characterize the role of each cell type in response to MF radiation and demonstrate the interdependence of each cell's response to ionizing radiation. The identified genes modulated by radiation and coculture provide guidance for future experiments to test hypotheses concerning specific factors mediating the beneficial effects of BMEC on HSPC. This information will prove useful in the search for medical countermeasures to radiation-induced hematopoietic injury.


Assuntos
Células da Medula Óssea/efeitos da radiação , Técnicas de Cocultura , Células Endoteliais/efeitos da radiação , Células-Tronco Hematopoéticas/efeitos da radiação , Antígenos CD34/análise , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos da radiação , Linhagem Celular , Proliferação de Células/efeitos da radiação , Técnicas de Cocultura/métodos , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Raios gama , Regulação da Expressão Gênica/efeitos da radiação , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Nêutrons , Fenótipo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Lesões por Radiação/prevenção & controle , Transdução de Sinais/efeitos da radiação
20.
Acta Haematol ; 141(3): 189-198, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30840964

RESUMO

Calorie restriction (CR) has been studied as a way to prolong longevity, and CR before chemotherapy can reduce hematological toxicity in cancer patients. We investigated the influence of fasting on immune cells and immature hematopoietic cells. In fasted mice, there was a significant reduction in the hematopoietic stem cell count but no significant difference for progenitor cells. Colony assays showed no difference and the rates of early and late apoptosis were almost identical when comparing fasted and control mice. DNA cell cycle analysis of immature bone marrow (BM) cells showed that CR caused a significant increase in the percentage in the G0/G1 phase and decreases in the S and G2/M phases. We detected a remarkable increase of T cells in the BM of fasted mice. CD44- naïve CD8+ T cells were more numerous in fasted BM, as were naïve CD4+ T cells, and part of those T cells showed less tendency in the G0/G1 phase. Immature hematopoietic cells remained in a relatively quiescent state and retention of colony-forming capacity during CR. The number of naïve T cells in the BM of fasted mice increased. These findings imply immature hematopoietic cells and some lymphoid cells can survive starvation, whilst maintaining their function.


Assuntos
Medula Óssea/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Pontos de Checagem do Ciclo Celular/fisiologia , Jejum/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Células-Tronco Hematopoéticas/citologia , Camundongos
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