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1.
Stem Cells Int ; 2017: 3615729, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28781596

RESUMO

Antitumor efficacy of systemically administered oncolytic adenoviruses (OAdv) is limited due to diverse factors such as liver sequestration, neutralizing interactions in blood, elimination by the immune system, and physical barriers in tumors. It is therefore of clinical relevance to improve OAdv bioavailability and tumor delivery. Among the variety of tumor-targeting strategies, the use of stem cells and specifically bone marrow-derived mesenchymal stem cells (BM-MSCs) is of particular interest due to their tumor tropism and immunomodulatory properties. Nonetheless, the invasive methods to obtain these cells, the low number of MSCs present in the bone marrow, and their restricted in vitro expansion represent major obstacles for their use in cancer treatments, pointing out the necessity to identify an alternative source of MSCs. Here, we have evaluated the use of menstrual blood-derived mesenchymal stem cells (MenSCs) as cell carriers for regional delivery of an OAdv in the tumor. Our results indicate that MenSCs can be isolated without invasive methods, they have an increased proliferation rate compared to BM-MSCs, and they can be efficiently infected with different serotype 5-based capsid-modified adenoviruses, leading to viral replication and release. In addition, our in vivo studies confirmed the tumor-homing properties of MenSCs after regional administration.

2.
Trauma (Majadahonda) ; 26(1): 4-10, ene.-mar. 2015. ilus
Artigo em Espanhol | IBECS | ID: ibc-138592

RESUMO

Objetivo: Generar células madre mesenquimales humanas (MSCs) modificadas para optimizar su potencial de diferenciación osteogénica, destinadas a su empleo en implantes cerámicos para regeneración ósea. Material y método: Se emplearon ratones inmunodeficientes NOD/SCID (3-6 ratones por condición experimental y ensayo) y se generaron vectores lentivirales basados en la recombinasa Cre, que sobreexpresan el factor regulador del proceso osteogénico Dlx5 (o la proteína fluorescente GFP como control) de forma autolimitada en el tiempo. Estos vectores se utilizaron para transducir hMSCs, y su potencial osteogénico se analizó in vitro e in vivo en un modelo de formación de hueso heterotópico en ratón. Resultados: Las hMSCs transducidas con los vectores que expresan Dlx5 de forma autolimitada fueron capaces de diferenciarse eficientemente a hueso de forma espontánea, de manera similar a las hMSCs control en presencia del factor osteoinductor BMP-2. Conclusión: Hemos desarrollado un sistema de modificación de hMSCs para aumentar su potencial osteogénico que consiste en un vector lentiviral que expresa el factor osteoinductor Dlx5 de forma autolimitada. Las hMSCs modificadas diferencian a hueso de manera eficiente, tanto in vitro como in vivo (AU)


Objective: This article proposes the generation of modified human mesenchymal stem cells (hMSCs) for optimizing their osteogenic differentiation potential, in order to be employed in ceramic implants for bone regeneration. Material and method: We have generated lentiviral vectors based on Cre recombinase, which lead to overexpression of a regulatory factor of osteogenic process, Dlx5 (or GFP fluorescent protein as a control), in a selflimited fashion. We have transduced hMSCs with these vectors, and we have analyzed their osteogenic potential both in vitro and in vivo in a model of heterotopic bone formation in mice. For this purpose we have used immunodeficient NOD/SCID mice (3-6 mice per condition and experiment). Results: hMSCs transduced with self-limited Dlx5-expressing vectors efficiently differentiate into bone in vitro and in vivo, similar to control hMSCs in the presence of osteoinductive factor BMP-2. Conclusion: We have developed a system to modify hMSCs in order to improve their osteogenic potential. This system consists of a lentiviral vector which expresses osteoinductive factor Dlx5 in a self-limited fashion. Modified hMSCs efficiently differentiate into bone, both in vitro and in vivo (AU)


Assuntos
Animais , Feminino , Masculino , Camundongos , Células-Tronco/classificação , Células-Tronco/fisiologia , Transplante de Células-Tronco/métodos , Regeneração Óssea/fisiologia , Lentivirus/isolamento & purificação , Terapia Baseada em Transplante de Células e Tecidos/métodos , Terapia Baseada em Transplante de Células e Tecidos , Terapia Baseada em Transplante de Células e Tecidos/veterinária , Doenças Ósseas/terapia , Doenças Ósseas/veterinária , Pesquisa com Células-Tronco , Diferenciação Celular/fisiologia , Terapia Baseada em Transplante de Células e Tecidos/instrumentação , Terapia Baseada em Transplante de Células e Tecidos/normas , Terapia Baseada em Transplante de Células e Tecidos/tendências
3.
Allergy ; 69(6): 730-40, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24750069

RESUMO

BACKGROUND: Mesenchymal stem cells may offer therapeutic potential for asthma due to their immunomodulatory properties and host tolerability, yet prior evidence suggests that bloodborne progenitor cells may participate in airway remodeling. Here, we tested whether mesenchymal stem cells administered as anti-inflammatory therapy may favor airway remodeling and therefore be detrimental. METHODS: Adipose tissue-derived mesenchymal stem cells were retrovirally transduced to express green fluorescent protein and intravenously injected into mice with established experimental asthma induced by repeat intranasal house dust mite extract. Controls were house dust mite-instilled animals receiving intravenous vehicle or phosphate-buffered saline-instilled animals receiving mesenchymal stem cells. Data on lung function, airway inflammation, and remodeling were collected at 72 h after injection or after 2 weeks of additional intranasal challenge. RESULTS: The mesenchymal stem cells homed to the lungs and rapidly downregulated airway inflammation in association with raised T-helper-1 lung cytokines, but such effect declined under sustained allergen challenge despite a persistent presence of mesenchymal stem cells. Conversely, airway hyperresponsiveness and contractile tissue underwent a late reduction regardless of continuous pathogenic stimuli and inflammatory rebound. Tracking of green fluorescent protein did not show mesenchymal stem cell integration or differentiation in airway wall tissues. CONCLUSIONS: Therapeutic mesenchymal stem cell infusion in murine experimental asthma is free of unwanted pro-remodeling effects and ameliorates airway hyper-responsiveness and contractile tissue remodeling. These outcomes support furthering the development of mesenchymal stem cell-based asthma therapies, although caution and solid preclinical data building are warranted.


Assuntos
Remodelação das Vias Aéreas , Asma/metabolismo , Asma/patologia , Células-Tronco Mesenquimais/metabolismo , Animais , Asma/imunologia , Asma/terapia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Movimento Celular/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Genes Reporter , Vetores Genéticos/genética , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Transplante de Células-Tronco Mesenquimais , Camundongos , Retroviridae/genética , Transdução Genética
4.
Rev. clín. esp. (Ed. impr.) ; 213(6): 293-197, ago.-sept. 2013.
Artigo em Espanhol | IBECS | ID: ibc-115028

RESUMO

Mujer de 62 años, que consulta para valoración de tratamiento de diabetes mellitus tipo 2 (DM2) de 4 años de evolución, en tratamiento con metformina 850mg/12h, sin complicaciones crónicas asociadas. Presenta hipertensión y dislipemia. Tratada con candesartán/hidroclorotiazida 32/12,5mg/día y atorvastatina 40mg/día. Pesaba 92kg y medía 162cm (IMC:35,1kg/m2). En el último control analítico, glucemia basal 168mg/dl y HbA1c 7,5%. La microalbuminuria era negativa. Las cifras de presión arterial y el perfil lipídico se encontraban dentro de los objetivos terapéuticos. Hace 2 años tuvo una fractura de Colles no traumática en la muñeca izquierda motivo por el que toma un suplemento de calcio y vitamina D diariamente y bifosfonato alendronato una vez por semana. En resumen, nos encontramos ante una mujer con obesidad y DM2, con un control metabólico inadecuado, que además presenta antecedentes de fractura por fragilidad. ¿Cómo debe ser evaluada y tratada esta paciente?(AU)


A 62-year-old woman consulted for evaluation of treatment for her type 2 diabetes diagnosed four years ago. He had been received treatment with metformin 850mg twice, with no chronic associated complications. She had hypertension and dyslipidemia. She was being treated with candesartan/hydrochlorothiazide 32/12.5mg and atorvastatin 40mg. Her weight was 92kg and height 162cm (BMI, 35.1kg/m2). The last analysis showed fasting glucose 168mg/dl and glycated hemoglobin 7.5%, Microalbuminuria was negative. Blood pressure and lipid profile were within the therapeutic range. Two years ago she suffered a nontraumatic Colle's fracture in her left arm for which she was taking a daily calcium and vitamin D supplement and weekly alendronate. In summary, this is an obese female patient with type 2 diabetes mellitus and inadequate metabolic control, She also has a history of fragility fracture. How should this patient be evaluated and treated?(AU)


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Osteoporose/complicações , Osteoporose/diagnóstico , Hormônios Gastrointestinais/metabolismo , Hormônios Gastrointestinais/farmacocinética , Hormônios Gastrointestinais/uso terapêutico , Metformina/uso terapêutico , Fatores de Risco , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipertensão/complicações , Hiperlipidemias/complicações , Hiperlipidemias/tratamento farmacológico , Hidroclorotiazida/uso terapêutico , Incretinas/metabolismo , Incretinas/uso terapêutico
5.
Rev Clin Esp (Barc) ; 213(6): 293-7, 2013.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26530941

RESUMO

A 62-year-old woman consulted for evaluation of treatment for her type 2 diabetes diagnosed four years ago. He had been received treatment with metformin 850mg twice, with no chronic associated complications. She had hypertension and dyslipidemia. She was being treated with candesartan/hydrochlorothiazide 32/12.5mg and atorvastatin 40mg. Her weight was 92kg and height 162cm (BMI, 35.1kg/m(2)). The last analysis showed fasting glucose 168mg/dl and glycated hemoglobin 7.5%, Microalbuminuria was negative. Blood pressure and lipid profile were within the therapeutic range. Two years ago she suffered a nontraumatic Colle's fracture in her left arm for which she was taking a daily calcium and vitamin D supplement and weekly alendronate. In summary, this is an obese female patient with type 2 diabetes mellitus and inadequate metabolic control, She also has a history of fragility fracture. How should this patient be evaluated and treated?

6.
Clin. transl. oncol. (Print) ; 13(9): 611-616, sept. 2011. ilus
Artigo em Inglês | IBECS | ID: ibc-125865

RESUMO

Over the last decade, genetic and cell biology studies have indicated that tumour growth is not only determined by malignant cancer cells themselves, but also by the tumour microenvironment. Cells present in the tumour microenvironment include fibroblasts, vascular, smooth muscle, adipocytes, immune cells and mesenchymal stem cells (MSC). The nature of the relationship between MSC and tumour cells appears dual and whether MSC are pro- or anti-tumorigenic is a subject of controversial reports. This review is focused on the role of MSC and bone marrow (BM) niches in cancer (AU)


Assuntos
Humanos , Animais , Masculino , Feminino , Células da Medula Óssea/patologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/patologia , Nicho de Células-Tronco , Antineoplásicos/farmacologia , Células da Medula Óssea , Células da Medula Óssea/fisiologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Metástase Neoplásica , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/fisiologia , Células-Tronco Mesenquimais/fisiologia , Nicho de Células-Tronco/fisiologia
7.
Cancer Gene Ther ; 17(7): 476-83, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20168350

RESUMO

Treatment of metastatic tumors with engineered adenoviruses that replicate selectively in tumor cells is a new therapeutic approach in cancer. Systemic administration of these oncolytic adenoviruses lack metastatic targeting ability. The tumor stroma engrafting property of intravenously injected mesenchymal stem cells (MSCs) may allow the use of MSCs as cellular vehicles for targeted delivery. In this work, we study the safety and the efficacy of infusing autologous MSCs infected with ICOVIR-5, a new oncolytic adenovirus, for treating metastatic neuroblastoma. Four children with metastatic neuroblastoma refractory to front-line therapies received several doses of autologous MSCs carrying ICOVIR-5, under an approved preliminary study. The tolerance to the treatment was excellent. A complete clinical response was documented in one case, and the child is in complete remission 3 years after this therapy. We postulate that MSCs can deliver oncolytic adenoviruses to metastatic tumors with very low systemic toxicity and with beneficial antitumor effects.


Assuntos
Células-Tronco Mesenquimais/virologia , Neuroblastoma/terapia , Terapia Viral Oncolítica/métodos , Linhagem Celular Tumoral , Pré-Escolar , Humanos , Masculino , Neuroblastoma/patologia , Neuroblastoma/virologia , Vírus Oncolíticos/fisiologia
9.
Br J Sports Med ; 43(3): 221-3, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18400877

RESUMO

Circulating mesenchymal cells (cMCs) have a potential for regenerating damaged tissue, e.g., ischaemic myocardium. In patients (age range: 53-76 years) with stable coronary artery disease cMCs were determined before and after dynamic exercise of moderate (< respiratory compensation threshold (RCT)) (n = 9 patients) or high intensity (>RCT) (n = 11). Only high-intensity exercise (i.e., provoking signs of myocardial ischaemia in 3 patients and ventricular extrasystoles in another) induced a significant increase in cMCs (p = 0.009). These results support the hypothesis that intense exercise (near or at the point of myocardial ischaemia) is a potent stimulus for MC mobilisation.


Assuntos
Movimento Celular , Doença da Artéria Coronariana/reabilitação , Terapia por Exercício/métodos , Células-Tronco Mesenquimais/fisiologia , Idoso , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
10.
J Cell Mol Med ; 12(6B): 2552-65, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19210755

RESUMO

Mesenchymal stem cells (MSCs) from adult somatic tissues may differentiate in vitro and in vivo into multiple mesodermal tissues including bone, cartilage, adipose tissue, tendon, ligament or even muscle. MSCs preferentially home to damaged tissues where they exert their therapeutic potential. A striking feature of the MSCs is their low inherent immunogenicity as they induce little, if any, proliferation of allogeneic lymphocytes and antigen-presenting cells. Instead, MSCs appear to be immunosuppressive in vitro. Their multilineage differentiation potential coupled to their immuno-privileged properties is being exploited worldwide for both autologous and allogeneic cell replacement strategies. Here, we introduce the readers to the biology of MSCs and the mechanisms underlying immune tolerance. We then outline potential cell replacement strategies and clinical applications based on the MSCs immunological properties. Ongoing clinical trials for graft-versus-host-disease, haematopoietic recovery after co-transplantation of MSCs along with haematopoietic stem cells and tissue repair are discussed. Finally, we review the emerging area based on the use of MSCs as a target cell subset for either spontaneous or induced neoplastic transformation and, for modelling non-haematological mesenchymal cancers such as sarcomas.


Assuntos
Doença , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Modelos Biológicos , Animais , Ensaios Clínicos como Assunto , Humanos , Tolerância Imunológica , Células-Tronco Mesenquimais/imunologia
11.
An Pediatr (Barc) ; 65(3): 198-204, 2006 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-16956497

RESUMO

BACKGROUND: Conventional prognostic factors for relapse in patients with acute lymphoblastic leukemia (ALL) are the main basis of risk-stratified treatments. OBJECTIVES: To analyze conventional risk factors for relapse and design a predictive model for relapse in our series, after 20 years of experience in treating ALL. PATIENTS AND METHOD: We performed a multivariate analysis of conventional prognostic factors in the treatment of ALL in our unit and compared them with the risk groups in the Berlin-Frankfurt-Münster (BFM-ALL) treatment protocols. RESULTS: Between 1984 and 2004, 232 children were diagnosed with ALL and treated according to the different versions of the BFM protocols (BFM83, BFM86, BFM90 and BFM95) at the Hospital Niño Jesús, Madrid, Spain. The event-free survival for all patients was 79.4 % (95 % CI: 72.7-85.4). Overall survival among patients who relapsed was 10.72 % (95 % CI: 6-27.3). The only significant prognostic factor for relapse identified by multivariate analysis was leukocyte [white blood cell (WBC)] count higher than 80,000/ml at diagnosis (hazard ratio [HR]: 4.63; 95 % CI: 1.61-13.3; p 5 0,004). The sensitivity and specificity of WBC in predicting relapses were 31.4 % and 87.5 %, respectively. The sensitivity and specificity of BFM risk group stratification in predicting relapses were 25 and 85.9 respectively. CONCLUSIONS: A leukocyte count at diagnosis higher than 80,000/ml and BFM risk-stratified treatment have insufficient sensitivity and specificity to identify relapses.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Asparaginase/uso terapêutico , Criança , Pré-Escolar , Ciclofosfamida/uso terapêutico , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Etoposídeo/uso terapêutico , Feminino , Humanos , Lactente , Masculino , Mercaptopurina/uso terapêutico , Metotrexato/uso terapêutico , Análise Multivariada , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Prednisolona/uso terapêutico , Prednisona/uso terapêutico , Prognóstico , Recidiva , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Vincristina/uso terapêutico
12.
An. pediatr. (2003, Ed. impr.) ; 65(3): 198-204, sept. 2006. ilus, tab
Artigo em Es | IBECS | ID: ibc-051210

RESUMO

Antecedentes Los factores pronósticos en el tratamiento de la leucemia linfoblástica aguda (LLA) son la base del tratamiento adaptado al grupo de riesgo. Objetivos Analizar los factores de riesgo convencionales y establecer un modelo predictivo de recaída en nuestra serie, tras 20 años de experiencia en el tratamiento de la LLA. Pacientes y método Realizamos un análisis multivariante de los factores pronósticos convencionales en el tratamiento de la LLA y los comparamos con los grupos de riesgo del protocolo de tratamiento Berlín-Frankfurt-Münster (LLA-BFM), en nuestra unidad. Resultados Entre 1984 y 2004, un total de 232 niños fueron diagnosticados de LLA y tratados siguiendo el protocolo BFM en sus diferentes versiones (BFM83, BFM86, BFM90 y BFM95). La supervivencia libre de episodios de la serie fue de 79,4 % (IC 95 %: 72,7-85,4). La supervivencia global de los pacientes que recayeron fue de 10,72 % (IC 95 %: 6-27,3). La única variable predictora en el análisis multivariante fue el número de leucocitos al diagnóstico mayor de 80.000/ml (hazard ratio [HR]: 4,63; IC 95 %: 1,61-13,3; p 5 0,004). La sensibilidad y especificidad del número de leucocitos al diagnóstico mayor de 80.000/ml para predecir la recaída fue en nuestra serie de 31,4 y 87,5, respectivamente. La sensibilidad y especificidad de los grupos de riesgo BFM para predecir la recaída fue de 25 y 85,9, respectivamente. Conclusiones El número de leucocitos al diagnóstico mayor de 80.000/ml o los grupos de tratamiento adaptados al riesgo según las variables convencionales no tienen suficiente sensibilidad y especificidad para identificar las recaídas


Background Conventional prognostic factors for relapse in patients with acute lymphoblastic leukemia (ALL) are the main basis of risk-stratified treatments. Objectives To analyze conventional risk factors for relapse and design a predictive model for relapse in our series, after 20 years of experience in treating ALL. Patients and method We performed a multivariate analysis of conventional prognostic factors in the treatment of ALL in our unit and compared them with the risk groups in the Berlin-Frankfurt-Münster (BFM-ALL) treatment protocols. Results Between 1984 and 2004, 232 children were diagnosed with ALL and treated according to the different versions of the BFM protocols (BFM83, BFM86, BFM90 and BFM95) at the Hospital Niño Jesús, Madrid, Spain. The event-free survival for all patients was 79.4 % (95 % CI: 72.7-85.4). Overall survival among patients who relapsed was 10.72 % (95 % CI: 6-27.3). The only significant prognostic factor for relapse identified by multivariate analysis was leukocyte [white blood cell (WBC)] count higher than 80,000/ml at diagnosis (hazard ratio [HR]: 4.63; 95 % CI: 1.61-13.3; p 5 0,004). The sensitivity and specificity of WBC in predicting relapses were 31.4 % and 87.5 %, respectively. The sensitivity and specificity of BFM risk group stratification in predicting relapses were 25 and 85.9 respectively. Conclusions A leukocyte count at diagnosis higher than 80,000/ml and BFM risk-stratified treatment have insufficient sensitivity and specificity to identify relapses


Assuntos
Lactente , Criança , Pré-Escolar , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Mercaptopurina/uso terapêutico , Asparaginase/uso terapêutico , Ciclofosfamida/uso terapêutico , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Etoposídeo/uso terapêutico , Metotrexato/uso terapêutico , Prednisona/uso terapêutico
13.
Br J Sports Med ; 40(8): 719-22, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16807304

RESUMO

Mesenchymal cells recruited to damaged tissues must circulate through the bloodstream. The absolute numbers of circulating mesenchymal stem cells (cMSCs) in two different models of acute and chronic skeletal muscle injury were determined. cMSCs were present in significantly higher numbers in both models than in healthy controls. These results support the hypothesis that MSCs are mobilised into the bloodstream after skeletal muscle tissue damage. These two models (acute and chronic) would be of value in the search for molecular mediators of mobilisation of MSCs into the circulation.


Assuntos
Traumatismos em Atletas/metabolismo , Células-Tronco Mesenquimais/metabolismo , Músculo Esquelético/lesões , Corrida/fisiologia , Adulto , Movimento Celular/fisiologia , Creatina Quinase/sangue , Feminino , Citometria de Fluxo , Doença de Depósito de Glicogênio Tipo V/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo
16.
Gene Ther ; 10(16): 1328-35, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12883529

RESUMO

Autologous bone marrow transplantation is an alternative therapeutic option for acute myeloid leukemia patients lacking a compatible donor. However, bone marrow from these patients may contain residual leukemic cells that should be ideally eliminated prior to the infusion of the graft. With the aim of developing more efficient protocols of graft purging, adenoviral-mediated gene transfer protocols have been conducted. We studied whether suicide adenoviral vectors expressing the cytosine deaminase gene (AdCD) could be used for selectively killing leukemic WEHI-3B cells. The AdCD transduction followed by the 5-fluorocytosine exposure abrogated the growth of WEHI-3B cells in vitro, with a minimal effect on normal hematopietic progenitors. To test the efficacy of the purging protocol in vivo, bone marrow cells were mixed with syngenic WEHI-3B cells and this chimeric cell population was transduced with AdCD vectors. Infected cells were injected into myeloablated Balb-c mice, which then received a 5-fluorocytosine treatment for 4 days. All mice transplanted with unpurged bone marrow developed leukemia and died. However, 90% of recipients receiving the purging treatment were healthy up to 9 months post-transplantation and had a perfectly re-established hematopoietic system, without any signal of leukemic cell presence. In conclusion, suicide adenoviral vectors are proposed as a tool for the purging of Adenoviral-susceptible myeloid leukemia cells contaminating autologous bone marrow grafts.


Assuntos
Adenoviridae/genética , Purging da Medula Óssea/métodos , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Leucemia/terapia , Transdução Genética/métodos , Animais , Transplante de Medula Óssea , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Transplante Autólogo
17.
Mol Ther ; 3(1): 70-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11162313

RESUMO

On the basis of the susceptibility of normal myelomonocytic cells to adenoviral vectors, we have studied the possibility of selectively transducing myelomonocytic murine leukemic cells (WEHI-3B) with regular (Reg-Ad) and genetically modified (RGD-Ad) adenoviral vectors. An 8-h incubation of WEHI-3B cells with 100 pfu of Reg-Ad vectors/cell resulted in the whole population becoming positive for transgene expression. Under identical conditions of infection, 20-30% of mouse bone marrow (BM) cells were positive for the transgene. When RGD-Ad vectors were used, a brief exposure (10 min) of WEHI-3B cells to 150 pfu of the virus/cell was enough for 100% of the leukemia cells to become positive for the marker transgene (EGFP). Under these conditions, only 15-20% of BM cells and of primitive hematopoietic progenitors (Lin(-)Sca-1(+) cells) became EGFP(+), indicating an improved selectivity of the vectors for the leukemic cells. The incubation of WEHI-3B but not normal BM cells with soluble fiber protein (FP) inhibited the infection with Reg-Ad. The use of the RGD-Ad bypassed the FP-CAR interaction required for the transduction of WEHI-3B cells with Reg-Ad, suggesting that the abrogation of this requirement accounts for the improved infectivity of these leukemic cells and for the selectivity of RGD-Ad in targeting WEHI-3B leukemia cells.


Assuntos
Adenoviridae/genética , Leucemia/genética , Oligopeptídeos/genética , Transdução Genética , Animais , Células da Medula Óssea/metabolismo , Células Cultivadas , Citometria de Fluxo , Terapia Genética/métodos , Vetores Genéticos , Células-Tronco Hematopoéticas , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Terciária de Proteína , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transgenes , Células Tumorais Cultivadas , beta-Galactosidase/metabolismo
18.
Leukemia ; 14(3): 457-65, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10720142

RESUMO

With the aim of developing a model mimicking the relapse of patients transplanted with leukemia-contaminated grafts, myelomonocytic leukemia WEHI-3B D+ cells were first transduced with a retroviral vector encoding the low-affinity human nerve growth factor receptor (NGFr). Clones with a stable and homogeneous expression of the transgene and with a similar in vitro behavior to the parental cell line were selected for further experiments. The analysis of bone marrow (BM) contaminated with WEHI-3B/NGFr cells revealed a linear correlation (r2 = 0.999) between the actual values of BM contamination and the experimental data determined by flow cytometry. Balb/c mice were myeloablated and transplanted with syngenic BM contaminated with graded numbers of leukemic cells; dose-dependent survival curves were obtained, regardless of whether parental or WEHI-3B/NGFr cells were infused. The leukemia dissemination in recipients transplanted with WEHI-3B/NGFr contaminated grafts was easily determined by means of simple flow cytometry analysis of the NGFr marker. A leukemia dose-dependent increase in the number of PB leukocytes was observed in transplanted recipients at 20 days post-transplantation with no changes in myelomonocytic cells. As deduced from our observations, the transplantation of syngenic BM contaminated with WEHI-3B/NGFr cells constitutes an improved model of autograft-mediated leukemia relapse and a good tool for studies of leukemia cell purging.


Assuntos
Purging da Medula Óssea , Transplante de Medula Óssea/efeitos adversos , Genes Reporter , Leucemia Mielomonocítica Aguda/patologia , Recidiva Local de Neoplasia/etiologia , Receptores de Fator de Crescimento Neural/genética , Transplante Autólogo/efeitos adversos , Células Tumorais Cultivadas/transplante , Animais , Contagem de Células , DNA de Neoplasias/análise , Modelos Animais de Doenças , Citometria de Fluxo , Vetores Genéticos/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Quimera por Radiação , Retroviridae/genética , Transfecção , Falha de Tratamento , Células Tumorais Cultivadas/virologia
19.
Arch Androl ; 37(2): 127-33, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8886262

RESUMO

Increasing evidence suggests the presence of local modulators that contribute to testicular function regulation in rats. The seminiferous tubules and Sertoli cell factors influence the steroidogenic activity of Leydig cells. Addition of Sertoli cell conditioned media to primary cultures of adult rat Leydig cells produces in a dose-dependent manner an inhibition of testosterone production with a concomitant decrease in the C21 delta 4-intermediates of the steroidogenic pathway, modifying the C21/C19 ratios in normal cells. The nature and mechanisms of action of this putative modulating activity are currently under study.


Assuntos
Androgênios/biossíntese , Meios de Cultivo Condicionados , Células Intersticiais do Testículo/metabolismo , Células de Sertoli/metabolismo , 17-alfa-Hidroxiprogesterona/metabolismo , Animais , Células Cultivadas , Masculino , Pregnenolona/biossíntese , Progesterona/biossíntese , Ratos , Ratos Wistar , Testosterona/biossíntese
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