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2.
Vox Sang ; 118(9): 783-789, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37533171

RESUMO

BACKGROUND AND OBJECTIVES: Bone marrow (BM) harvesting is one of the essential sources of stem cells for haematopoietic stem cell transplantation. In 2019, commercial BM collection kits became unavailable in Europe. Consequently, we created an in-house BM collection kit as an alternative. MATERIALS AND METHODS: We compared two groups of BM collections. The first collections were taken using an in-house kit from June 2022 through February 2023 and the second with a commercial kit from February 2021 through May 2022. These all took place at seven collection centres (CC). We analysed the harvest quality (cell blood count, CD34+ cells, viability, potency and sterility), the incidents occurring with each kit and the time to neutrophil and platelet engraftment in recipients. RESULTS: A total of 23 donors underwent BM harvesting with the in-house kit and 23 with the commercial one. Both cohorts were comparable regarding donor characteristics, CC and time to procedure. No statistical differences were found in harvest quality between the in-house and commercial kits. A new transfusion set was required in three BM harvests (13%) with the in-house kit because of filter clogging. The median time to neutrophil and platelet engraftment was 21 days for both cohorts and 29 days (in-house) and 33 days (commercial), p = 0.284, respectively. CONCLUSION: The in-house BM collection kit offers a real approach to solve the diminished supply of commercial kits. A higher risk of filter clogging was observed compared with commercial kits due to the lack of 850 and 500 µm filters.


Assuntos
Transplante de Medula Óssea , Transplante de Células-Tronco Hematopoéticas , Humanos , Transplante de Medula Óssea/métodos , Medula Óssea , Transplante Homólogo , Doadores de Tecidos
3.
Transplant Cell Ther ; 29(9): 572.e1-572.e13, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37290691

RESUMO

During the first outbreak of an emergent virus, methods need to be developed to rapidly establish suitable therapies for patients with high risk of severe disease caused by the pathogen. Considering the importance of the T-cell response in controlling viral infections, adoptive cell therapy with virus-specific T cells has been used as a safe and effective antiviral prophylaxis and treatment for immunocompromised patients. The main objective of this study was to establish an effective and safe method to cryostore whole blood as starting material and to adapt a T-cell activation and expansion protocol to generate an off-the-shelf antiviral therapeutic option. Additionally, we studied how memory T-cell phenotype, clonality based on T-cell receptor, and antigen specificity could condition characteristics of the final expanded T-cell product. Twenty-nine healthy blood donors were selected from a database of convalescent plasma donors with a confirmed history of SARS-CoV-2 infection. Blood was processed using a fully automated, clinical-grade, and 2-step closed system. Eight cryopreserved bags were advanced to the second phase of the protocol to obtain purified mononucleated cells. We adapted the T-cell activation and expansion protocol, without specialized antigen-presenting cells or presenting molecular structures, in a G-Rex culture system with IL-2, IL-7, and IL-15 cytokine stimulation. The adapted protocol successfully activated and expanded virus-specific T cells to generate a T-cell therapeutic product. We observed no major impact of post-symptom onset time of donation on the initial memory T-cell phenotype or clonotypes resulting in minor differences in the final expanded T-cell product. We showed that antigen competition in the expansion of T-cell clones affected the T-cell clonality based on the T-cell receptor ß repertoire. We demonstrated that good manufacturing practice of blood preprocessing and cryopreserving is a successful procedure to obtain an initial cell source able to activate and expand without a specialized antigen-presenting agent. Our 2-step blood processing allowed recruitment of the cell donors independently of the expansion cell protocol timing, facilitating donor, staff, and facility needs. Moreover, the resulting virus-specific T cells could be also banked for further use, notably maintaining viability and antigen specificity after cryopreservation.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/terapia , Soroterapia para COVID-19 , SARS-CoV-2 , Linfócitos T , Criopreservação , Surtos de Doenças , Antivirais
4.
Biotechnol Bioeng ; 120(9): 2717-2724, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36919270

RESUMO

Three dimensional (3D) bioprinting is an emerging technology that enables complex spatial modeling of cell-based tissue engineering products, whose therapeutic potential in regenerative medicine is enormous. However, its success largely depends on the definition of a bioprintable zone, which is specific for each combination of cell-loaded hydrogels (or bioinks) and scaffolds, matching the mechanical and biological characteristics of the target tissue to be repaired. Therefore proper adjustment of the bioink formulation requires a compromise between: (i) the maintenance of cellular critical quality attributes (CQA) within a defined range of specifications to cell component, and (ii) the mechanical characteristics of the printed tissue to biofabricate. Herein, we investigated the advantages of using natural hydrogel-based bioinks to preserve the most relevant CQA in bone tissue regeneration applications, particularly focusing on cell viability and osteogenic potential of multipotent mesenchymal stromal cells (MSCs) displaying tripotency in vitro, and a phenotypic profile of 99.9% CD105+ /CD45,- 10.3% HLA-DR,+ 100.0% CD90,+ and 99.2% CD73+ /CD31- expression. Remarkably, hyaluronic acid, fibrin, and gelatin allowed for optimal recovery of viable cells, while preserving MSC's proliferation capacity and osteogenic potency in vitro. This was achieved by providing a 3D structure with a compression module below 8.8 ± 0.5 kPa, given that higher values resulted in cell loss by mechanical stress. Beyond the biocompatibility of naturally occurring polymers, our results highlight the enhanced protection on CQA exerted by bioinks of natural origin (preferably HA, gelatin, and fibrin) on MSC, bone marrow during the 3D bioprinting process, reducing shear stress and offering structural support for proliferation and osteogenic differentiation.


Assuntos
Bioimpressão , Células-Tronco Mesenquimais , Hidrogéis/química , Osteogênese , Gelatina/química , Engenharia Tecidual/métodos , Fibrina/metabolismo , Alicerces Teciduais/química , Bioimpressão/métodos , Impressão Tridimensional
5.
Cytotherapy ; 25(1): 14-19, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36041984

RESUMO

BACKGROUND AIMS: To describe and analyze whether a hub-and-spoke organizational model could efficiently provide access to chimeric antigen receptor (CAR) T-cell therapy within a network of academic hospitals and address the growing demands of this complex and specialized activity. METHODS: The authors performed a retrospective evaluation of activity within the Catalan Blood and Tissue Bank network, which was established for hematopoietic stem cell transplantation to serve six CAR T-cell programs in academic hospitals of the Catalan Health Service. Procedures at six hospitals were followed from 2016 to 2021. Collection shipments of starting materials, CAR T-cell returns for storage and infusions for either clinical trials or commercial use were evaluated. RESULTS: A total of 348 leukocytapheresis procedures were performed, 39% of which were delivered fresh and 61% of which were cryopreserved. The network was linked to seven advanced therapy medicinal product manufacturers. After production, 313 CAR T-cell products were shipped back to the central cryogenic medicine warehouse located in the hub. Of the units received, 90% were eventually administered to patients. A total of 281 patients were treated during this period, 45% in clinical trials and the rest with commercially available CAR T-cell therapies. CONCLUSIONS: A hub-and-spoke organizational model based on an existing hematopoietic stem cell transplantation program is efficient in incorporating CAR T-cell therapy into a public health hospital network. Rapid access and support of growing activity enabled 281 patients to receive CAR T cells during the study period.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Receptores de Antígenos Quiméricos , Humanos , Imunoterapia Adotiva/métodos , Saúde Pública , Estudos Retrospectivos , Receptores de Antígenos de Linfócitos T
6.
Bone Marrow Transplant ; 57(10): 1531-1538, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35804055

RESUMO

Cryopreservation was recommended to ensure continuity in allogeneic hematopoietic progenitor cells (HPC) transplantation during the COVID-19 pandemic. Several groups have shown no impact on clinical outcomes for patients who underwent HPC transplantation with cryopreserved products during the first months of this pandemic. However, concerns about quality control attributes after cryopreservation have been raised. We investigated, in 155 allogeneic peripheral blood cryopreserved HPC, leukocytapheresis characteristics influencing viable CD34+ and CD3+ cells, and CFU-GM recoveries after thawing. Collection characteristics such as volume, nucleated cells (NC)/mL and hematocrit correlated with viable CD34+ and CD3+ cells recoveries after thawing in univariate analysis but only CD3+ cells remained statistically significant in multivariate analysis (r2 = 0.376; P = < 0.001). Additionally, transit time also showed correlation with viable CD34+ (r2 = 0.186), CD3+ (r2 = 0.376) and CFU-GM recoveries (r2 = 0.212) in multivariate analysis. Thus, diluting leukocytapheresis below 200 × 106 NC/mL, avoiding red cells contamination above 2%, cryopreserving below 250 × 106 NC/mL and minimizing transit time below 36 h, prevented poor viable CD34+ and CD3+ cells, and CFU-GM recoveries. In summary, optimizing leukocytapheresis practices and minimizing transportation time may better preserve the quality attributes of HPC when cryopreservation is indicated.


Assuntos
COVID-19 , Transplante de Células-Tronco Hematopoéticas , Antígenos CD34/análise , Sobrevivência Celular , Criopreservação , Células-Tronco Hematopoéticas , Humanos , Leucaférese , Pandemias
8.
Bone Marrow Transplant ; 56(10): 2489-2496, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34127808

RESUMO

Cryopreservation was recommended to ensure continuity of unrelated donor (UD) hematopoietic stem cell transplantation (HSCT) during COVID-19 pandemic. However, its impact on clinical outcomes and feasibility was not well known. We compared 32 patients who underwent UD HSCT using cryopreserved peripheral blood stem cells (PBSC) during the COVID-19 pandemic with 32 patients who underwent UD HSCT using fresh PBSC in the previous period. Median neutrophil engraftment was 17.5 and 17.0 days with cryopreserved and fresh grafts, respectively. Non-significant delays were found in platelet recovery days (25.5 versus 19.0; P = 0.192) and full donor chimerism days (35.0 and 31.5; P = 0.872) using cryopreserved PBSC. The rate of acute graft-versus-host disease at 100 days was 41% (95% CI [21-55%]) in cryopreserved group versus 31% (95% CI [13-46%]) in fresh group (P = 0.380). One-hundred days progression-relapse free survival and overall survival did not differ significantly. During COVID-19 pandemic, six frozen UD donations were not transfused and logistical and clinical issues regarding cryopreservation procedure, packaging, and transporting appeared. In summary, UD HSCT with cryopreserved PBSC was safe during this challenging time. More efforts are needed to ensure that all frozen grafts are transplanted and cryopreservation requirements are harmonized.


Assuntos
COVID-19 , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Criopreservação , Células-Tronco Hematopoéticas , Humanos , Pandemias , SARS-CoV-2 , Doadores não Relacionados
9.
Methods Mol Biol ; 2286: 251-261, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32705544

RESUMO

Tissue engineering products (TEP) are a new type of medicines resulting from the combination of cells, scaffolds, and/or signalling factors, which can be used for the regeneration of damaged tissues thus opening new avenues for the treatment of complex conditions. However, such combination of biologically active elements, particularly living cells, poses an unprecedented challenge for their production under pharmaceutical standards.In the methods presented here, we formulated two types of TEP based on the use of multipotent mesenchymal stromal cells with osteogenic potential combined with osteoinductive and osteoconductive bony particles from tissue bank embedded in a fibrin hydrogel that, altogether, can induce the generation of new tissue while adapting to the diverse architecture of bony defects. In agreement with pharmaceutical quality and regulatory requirements, procedures presented herein can be performed in compliance with current good manufacturing practices and be readily implemented in straightforward facilities at hospitals and academic institutions.


Assuntos
Regeneração Óssea , Adesivo Tecidual de Fibrina/química , Células-Tronco Mesenquimais/citologia , Cultura Primária de Células/métodos , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Células Cultivadas , Adesivo Tecidual de Fibrina/farmacologia , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia
10.
Bone Marrow Transplant ; 55(8): 1623-1631, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32303710

RESUMO

Allele-level HLA compatibility in cord blood transplantation, together with noninherited maternal antigen or NIMA matching, have been associated with better transplant outcomes. The aim of this work is to develop a cost-efficient high-resolution HLA typing strategy based on next-generation sequencing to improve the quality of the Barcelona Cord Blood Bank's inventory, and to investigate the impact of high-resolution HLA typing and NIMA determination on the preferential selection of cord blood for transplantation. In this line, the developed strategy was validated and the HLA-A, -B, -C, -DRB1, and -DQB1 genes of 5000 cord blood units and 2500 of their associated maternal samples were typed. Subsequently, three study groups of 2012 units each were monitored for up to 2 years: (1) units with high-resolution and maternal HLA typing, (2) units with high-resolution but not maternal typing, and (3) units typed at low-resolution for class I and only high-resolution for HLA-DRB1. Despite a trend toward a greater selection of units with high-resolution typing, no significant impact of these variables was observed. These results highlight the need for evidence-based and globally accepted criteria for cord blood selection, together with the necessity to improve the accessibility of clinicians to donor registry's data.


Assuntos
Tipagem e Reações Cruzadas Sanguíneas , Sequenciamento de Nucleotídeos em Larga Escala , Alelos , Cadeias HLA-DRB1 , Teste de Histocompatibilidade , Humanos
11.
Bone Marrow Transplant ; 55(7): 1229-1239, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32024991

RESUMO

The analysis of chimerism is crucial to determine the status of patients receiving hematopoietic stem cell transplantation. The variety of relevant techniques available today range from those that analyse nucleic acids (i.e. polymerase chain reaction based, next generation sequencing) and cellular phenotype (i.e. flow cytometry) to sophisticated imaging (particularly multimodal imaging using labelling agents). However, current developments of advanced therapies bring chimerism studies into a new dimension in which methods for detection of donor cells in the patient need to adapt to a wider range of cell- and gene-based medicines, routes of administration, target organs and pathologies. Herein we describe and analyze the toolkit of suitable labelling and detection methodologies with actual examples along with a discussion on challenges ahead and potential solutions. Remarkably, existing methods commonly used in chimerism analysis are suitable for use with new cell- and gene-based medicines. Indeed, new developments may facilitate the evolution and combination of such methodologies to the use of non-invasive and highly informative approaches.


Assuntos
Quimerismo , Transplante de Células-Tronco Hematopoéticas , Citometria de Fluxo , Humanos , Reação em Cadeia da Polimerase , Quimeras de Transplante
12.
Haematologica ; 105(2): 508-518, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31197069

RESUMO

Readthrough therapy relies on the use of small molecules that enable premature termination codons in mRNA open reading frames to be misinterpreted by the translation machinery, thus allowing the generation of full-length, potentially functional proteins from mRNA carrying nonsense mutations. In patients with hemophilia A, nonsense mutations potentially sensitive to readthrough agents represent approximately 16% of the point mutations. The aim of this study was to measure the readthrough effect of different compounds and to analyze the influence of premature termination codon context in selected nonsense mutations causing hemophilia A. To this end, primary fibroblasts from three patients with hemophilia A caused by nonsense mutations (p.W1586X, p.Q1636X and p.R1960X) and Chinese hamster ovary (CHO) cells transfected with 12 different plasmids encoding mutated F8 (p.Q462X, p.Q1705X, p.Q1764X, p.W274X, p.W1726X, p.W2015X, p.W2131X, p.R1715X, p.R1822X, p.R1960X, p.R2071X and p.R2228X) were treated with gentamicin, geneticin, PTC124, RTC13 or RTC14. Responses were assessed by analyzing not only F8 mRNA expression and FVIII biosynthesis (FVIII antigen by ELISA, western blot and immunofluorescence) but also the FVIII activity (by chromogenic assay). In the patients' fibroblasts, readthrough agents neither stabilized F8 mRNA nor increased FVIII protein or activity to detectable levels. In CHO cells, only in five of the 12 F8 variants, readthrough treatment increased both FVIII antigen and activity levels, which was associated with a reduction in intracellular accumulation of truncated forms and an increase in full-length proteins. These results provide experimental evidence of genetic context dependence of nonsense suppression by readthrough agents and of factors predicting responsiveness.


Assuntos
Códon sem Sentido , Hemofilia A , Animais , Células CHO , Cricetinae , Cricetulus , Hemofilia A/tratamento farmacológico , Hemofilia A/genética , Humanos , RNA Mensageiro/genética
13.
HLA ; 94(4): 347-359, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31353832

RESUMO

Allele-level HLA compatibility in cord blood transplantation has been associated with better transplant outcomes and is recommended as a selection criterion. It is also a crucial aspect for other therapeutic applications involving cord blood-derived cells. Determination of high-resolution HLA frequencies is an important step towards improving the quality of cord blood banks. We analyzed HLA-A, -B, -C, -DRB1, and -DQB1 allele frequencies in 5458 high-quality cord blood units from the Barcelona Cord Blood Bank and identified 275 class I and 121 class II HLA alleles. A*02:01, B*44:03, C*07:01, DRB1*07:01 and DQB1*03:01 were the most frequent alleles at each locus. We detected 26 novel alleles and were able to determine the presence or absence of some null alleles, including C*04:09N, in a large number of units. We also analyzed maternal HLA typing information for 1877 units to determine real haplotype frequencies and linkage disequilibrium. A*29:02-B*44:03-C*16:01-DRB1*07:01-DQB1*02:02 was the most frequent HLA haplotype and the DRB1-DQB1 gene pair contained the two-locus haplotypes with the strongest linkage disequilibrium values. Four of the 11 unique haplotypes identified in the HLA-homozygous cord blood units were the top-ranking haplotypes identified and were present in 18% of the cohort. This is the first study to report on HLA allele and haplotype frequencies for umbilical cord blood units from the Barcelona Cord Blood Bank and the largest study to date involving two fields of HLA resolution typing of Spanish registry data.


Assuntos
Sangue Fetal/imunologia , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Regiões 3' não Traduzidas , Alelos , Bancos de Sangue , Feminino , Frequência do Gene , Genótipo , Antígeno HLA-A2/genética , Antígeno HLA-B44/genética , Haplótipos , Homozigoto , Humanos , Desequilíbrio de Ligação , Masculino , Mães , Polimorfismo de Nucleotídeo Único , Gravidez
14.
Exp Neurol ; 286: 50-60, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27693617

RESUMO

Previous work by our group showed that transferring bone marrow cells transduced with a self-antigen induced immune tolerance and ameliorated experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis (MS). We also found that following retroviral transduction of murine bone marrow (BM) cells, the majority of cells generated and transduced were myeloid-derived suppressor cells (MDSCs). Here, we aimed to determine whether purified antigen-expressing MDSCs have similar therapeutic effects than those of unfractionated BM, and to investigate their potential mechanisms. We performed phenotypic and functional analyses in these cells using the same animal model, and we used purified antigen-expressing MDSCs in preventive and therapeutic approaches. These cells exerted therapeutic effects similar to those of BM cells, which depended upon self-antigen expression. The majority of monocytic (M)-MDSCs expressed the immunosuppressive molecule programmed death ligand-1 (PD-L1), CD80, CD86 and MHC class II molecules. Additionally, the animals infused with antigen-expressing cells exhibited lower percentages of activated T cells and higher percentages of B cells with a regulatory phenotype (B220+CD1dhigh CD5+) in the spleen than their respective controls. MDSCs expressing self-antigens, alloantigens or therapeutic transgenes are tolerogenic and can be exploited therapeutically in autoimmune diseases, transplantation and in gene therapy, respectively.


Assuntos
Autoantígenos/uso terapêutico , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/terapia , Células Supressoras Mieloides/fisiologia , Transferência Adotiva , Animais , Apoptose/fisiologia , Células da Medula Óssea/fisiologia , Sistema Nervoso Central/patologia , Citocinas/metabolismo , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/fisiopatologia , Feminino , Humanos , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Células Supressoras Mieloides/efeitos dos fármacos , Retroviridae/genética , Índice de Gravidade de Doença , Baço/patologia , Canais de Ânion Dependentes de Voltagem
15.
Clín. investig. arterioscler. (Ed. impr.) ; 22(2): 39-48, mar.-abr. 2010. graf, ilus
Artigo em Espanhol | IBECS | ID: ibc-87691

RESUMO

Background NOR-1 is a nuclear receptor that is over expressed in human atherosclerotic plaques. This receptor is involved in endothelial cell (EC) growth induced by vascular endothelial growth factor (VEGF) and other mitogens. Our aim was to analyze NOR-1 regulation by hypoxia in EC. Results Hypoxia increased NOR-1 mRNA levels in a time- and dose-dependent manner. Hypoxia-induced NOR-1 expression was prevented by BAPTA-AM (a calcium chelator) but not by inhibitors of p38 MAPK, MEK1/2 (..) (AU)


Background NOR-1 is a nuclear receptor that is over expressed in human atherosclerotic plaques. This receptor is involved in endothelial cell (EC) growth induced by vascular endothelial growth factor (VEGF) and other mitogens. Our aim was to analyze NOR-1 regulation by hypoxia in EC. Results Hypoxia increased NOR-1 mRNA levels in a time- and dose-dependent manner. Hypoxia-induced NOR-1 expression was prevented by BAPTA-AM (a calcium chelator) but not by inhibitors of p38 MAPK, MEK1/2 or protein kinase C (PKC) pathways. Incubation of EC with blocking antibodies against VEGF or SU5614 (a VEGF-R2 inhibitor) did not prevent hypoxia-induced NOR-1 expression. Hypoxia did not significantly induce early activation of cAMP response element binding protein (CREB), a key transcription factor involved in the up-regulation of NOR-1 expression by VEGF. In contrast, reduction of hypoxia-induced HIF-1¦Á protein levels by inhibitors of the PI3K/Akt/m TOR pathway or by siRNA against HIF-1, significantly counteracted hypoxia-induced NOR-1 up-regulation. In transient transfection assays, the activity of the NOR-1 promoter construct was increased by hypoxia or by co-transfection with an HIF-1¦Á expression plasmid. We identified a hypoxia response element in the NOR-1 promoter responsible for this hypoxia-mediated effect as shown by site-directed mutagenesis and serial deletions. Finally, over-expression of NOR-1 (using a bicistronic recombinant plasmid) decreased the rate of cells undergoing apoptosis (annexin V positive/propidium iodide negative), while inhibition of NOR-1 (using specific siRNA) increased cell apoptosis. Conclusions Therefore, HIF-1 modulates the expression of NOR-1, a transcription factor that regulates the survival response of EC to hypoxia (..) (AU)


Antecedentes El neuron-derived orphan receptor-1 (NOR-1) es un receptor nuclear que esta sobreexpresado en las lesiones ateroscleraticas humanas y que participa en la proliferacion de las celulas endoteliales (CE) en respuesta al factor de crecimiento del endotelial vascular (VEGF) y a otros (..) (AU)


Assuntos
Humanos , Mitógenos/análise , Apoptose/fisiologia , Hipóxia Celular/fisiologia , Células Endoteliais/fisiologia , Fator 1 Induzível por Hipóxia/análise , Fatores de Crescimento do Endotélio Vascular/análise , Aterosclerose/fisiopatologia
16.
Mol Cell Biol ; 29(21): 5828-42, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19720740

RESUMO

Hypoxia induces apoptosis but also triggers adaptive mechanisms to ensure cell survival. Here we show that the prosurvival effects of hypoxia-inducible factor 1 (HIF-1) in endothelial cells are mediated by neuron-derived orphan receptor 1 (NOR-1). The overexpression of NOR-1 decreased the rate of endothelial cells undergoing apoptosis in cultures exposed to hypoxia, while the inhibition of NOR-1 increased cell apoptosis. Hypoxia upregulated NOR-1 mRNA levels in a time- and dose-dependent manner. Blocking antibodies against VEGF or SU5614 (a VEGF receptor 2 inhibitor) did not prevent hypoxia-induced NOR-1 expression, suggesting that NOR-1 is not induced by the autocrine secretion of VEGF in response to hypoxia. The reduction of HIF-1 alpha protein levels by small interfering RNAs, or by inhibitors of the phosphatidylinositol-3 kinase (PI3K)/Akt pathway or mTOR, significantly counteracted hypoxia-induced NOR-1 upregulation. Intracellular Ca(2+) was involved in hypoxia-induced PI3K/Akt activation and in the downstream NOR-1 upregulation. A hypoxia response element mediated the transcriptional activation of NOR-1 induced by hypoxia as we show by transient transfection and chromatin immunoprecipitation assays. Finally, the attenuation of NOR-1 expression reduced both basal and hypoxia-induced cIAP2 (cellular inhibitor of apoptosis protein 2) mRNA levels, while NOR-1 overexpression upregulated cIAP2. Therefore, NOR-1 is a downstream effector of HIF-1 signaling involved in the survival response of endothelial cells to hypoxia.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Receptores de Esteroides/metabolismo , Receptores dos Hormônios Tireóideos/metabolismo , Apoptose , Comunicação Autócrina , Proteína 3 com Repetições IAP de Baculovírus , Hipóxia Celular , Sobrevivência Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Derme/citologia , Células Endoteliais/enzimologia , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Microvasos/citologia , Fosfatidilinositol 3-Quinases/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Elementos de Resposta/genética , Transdução de Sinais , Ubiquitina-Proteína Ligases , Veias Umbilicais/citologia , Regulação para Cima/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
17.
Thromb Haemost ; 99(2): 305-15, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18278179

RESUMO

Thrombin is a multifunctional serine protease generated at the site of vascular injury that transforms fibrinogen into fibrin, activates blood platelets and elicits multiple effects on a variety of cell types including endothelial cells, vascular smooth muscle cells (VSMC), monocytes, T lymphocytes and fibroblasts. Cellular effects of thrombin are mediated by protease-activated receptors (PARs), members of the G protein-coupled receptors that carry their own ligand which remains cryptic until unmasked by proteolytic cleavage. Thrombin signalling in platelets contributes to haemostasis and thrombosis. In normal arteries PARs are mainly expressed in endothelial cells, while their expression in VSMC is limited. Endothelial PARs participate in the regulation of vascular tone, vascular permeability and endothelial secretory activity while in VSMC they mediate contraction, migration, proliferation, hypertrophy and production of extracellular matrix. PARs contribute to the pro-inflammatory phenotype observed in endothelial dysfunction and their up-regulation in VSMC seems to be a key element in the pathogenesis of atherosclerosis and restenosis. In the last years a myriad of studies have emphasized the critical role of PAR signalling in thrombin mediated effects in haemostasis, inflammation, cancer and embryonic development. Lately, PARs have become a therapeutic target to inhibit platelet aggregation and thrombosis. Early data from a clinical trial (TRA-PCI) to evaluate safety and efficacy of a potent new oral thrombin receptor antagonist (TRA) have promisingly indicated that overall TRA treatment reduces adverse event rates without an increase in bleeding risk. In this paper we review cellular responses triggered by thrombin and their implication in vascular pathophysiology.


Assuntos
Aterosclerose/metabolismo , Receptores Ativados por Proteinase/metabolismo , Transdução de Sinais , Trombina/metabolismo , Trombose/metabolismo , Animais , Aterosclerose/sangue , Aterosclerose/tratamento farmacológico , Aterosclerose/fisiopatologia , Coagulação Sanguínea , Plaquetas/metabolismo , Constrição Patológica , Células Endoteliais/metabolismo , Hemorragia/sangue , Hemorragia/metabolismo , Humanos , Miócitos de Músculo Liso/metabolismo , Neovascularização Fisiológica , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Receptores Ativados por Proteinase/antagonistas & inibidores , Receptores Ativados por Proteinase/sangue , Recidiva , Transdução de Sinais/efeitos dos fármacos , Trombose/sangue , Trombose/tratamento farmacológico , Trombose/fisiopatologia
18.
Front Biosci ; 13: 2909-15, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17981763

RESUMO

Neuron-derived orphan receptor-1 (NOR-1) is a nuclear receptor recently involved in the onset and development of atherosclerosis. NOR-1 is induced in a cell-specific manner by extracellular stimuli. NOR-1 is over-expressed in human atherosclerotic plaques and in porcine arteries subjected to angioplasty, is induced by growth factors in vascular cells and it has been involved in cell migration and proliferation. This article examines the mechanisms that regulate NOR-1 in vascular cells and the effects of NOR-1 knockdown on cell growth induced by mitogens, in particular thrombin. Mitogenic stimuli up-regulates NOR-1 in endothelial cells (ECs) through multiple pathways, including increase of cytosolic calcium, activation of protein kinase C, mitogen-activated protein kinase (MAPK) (ERK1/2 and p38 MAPK) and downstream activation of cAMP response element binding protein (CREB). Inhibition of protease-activated receptor-1 (PAR-1) abolished thrombin-induced NOR-1 up-regulation and DNA synthesis. NOR-1 knockdown reduces DNA synthesis and EC re-growth in an in vitro model of wound repair. NOR-1 could be regarded as a new target to prevent endothelial effects triggered by thrombin and other mitogens.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Receptores de Esteroides/metabolismo , Receptores dos Hormônios Tireóideos/metabolismo , Trombina/química , Trombina/metabolismo , Trombina/fisiologia , Aterosclerose , Linhagem Celular , Proliferação de Células , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , DNA/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases , Mitógenos/metabolismo , Modelos Biológicos , Receptores de Trombina/metabolismo , Transcrição Gênica
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