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1.
Chemosphere ; 357: 141910, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582170

RESUMO

Growing quantities of biomass ashes (phyto-ashs) are currently produced worldwide due to the increasing biomass consumption in energy applications. Utilization of phyto-ash in agriculture is environmentally friendly solution. However, mechanisms involving the coordination of carbon metabolism and distribution in plants and soil amendment are not well known. In the present study, tobacco plants were chemically-fertilized with or without 2‰ phyto-ash addition. The control had sole chemical fertilizer; for two phyto-ash treatments, the one (T1) received comparable levels of nitrogen, phophorus, and potassium from phyto-ash and fertilizers as the control and another (T2) had 2‰ of phyto-ash and the same rates of fertilizers as the control. Compared with the control, phyto-ash addition improved the soil pH from 5.94 to about 6.35; T2 treatment enhanced soil available potassium by 30% but no difference of other elements was recorded among three treatments. Importantly, bacterial (but not fungal) communities were significantly enriched by phyto-ash addition, with the rank of richness as: T2 > T1 > control. Consistent with amelioration of soil properties, phyto-ash promoted plant growth through enlarged leaf area and photosynthesis and induced outgrowth of lateral roots (LRs). Interestingly, increased auxin content was recorded in 2nd and 3rd leaves and roots under phyto-ash application, also with the rank level as T2 > T1 > control, paralleling with higher transcripts of auxin synthetic genes in the topmost leaf and stronger [3H]IAA activity under phyto-ash addition. Furthermore, exogenous application of analog exogenous auxin (NAA) restored leaf area, photosynthesis and LR outgrowth to the similar level as T2 treatment; conversely, application of auxin transport inhibitor (NPA) under T2 treatment retarded leaf and root development. We demonstrated that phyto-ash addition improved soil properties and thus facilitated carbon balance within plants and biomass accumulation in which shifting auxin distribution plays an important role.


Assuntos
Biomassa , Fertilizantes , Ácidos Indolacéticos , Solo , Solo/química , Ácidos Indolacéticos/metabolismo , Nicotiana/metabolismo , Nicotiana/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Agricultura/métodos , Nitrogênio/metabolismo , Microbiologia do Solo , Carbono/metabolismo , Potássio/metabolismo
2.
Vaccine ; 40(49): 7065-7072, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273986

RESUMO

BACKGROUND: Unadjuvanted A/H7N9 vaccines are poorly immunogenic. The immune response is improved with the addition of MF59, an oil-in-water adjuvant. However, the cellular immunologic responses of MF59-adjuvanted A/H7N9 vaccine are not fully understood. METHODS: 37 participants were vaccinated with 2 doses of 2013 influenza A/H7N9 vaccine (at Days 1 and 21) with or without MF59 and enrolled in an immunology substudy. Responses were assessed at multiple timepoints (Days 0, 8, 21, 29, and 42) for hemagglutination inhibition (HAI) and neutralizing antibody (Neut) assays, memory B cell responses by enzyme-linked ImmunoSpot; circulating follicular helper T cells (cTFH) and CD4 + T cells by intracellular cytokine staining. RESULTS: MF59-adjuvanted influenza A/H7N9 vaccine induced significantly higher hemagglutination inhibition (HAI) and neutralizing antibody (Neut) responses when compared to unadjuvanted vaccine. The adjuvanted vaccine elicited significantly higher levels of Inducible T-cell Co-Stimulator (ICOS) expression by CXCR3+CXCR5+CD4+ cTFH cells, compared to unadjuvanted vaccine. The magnitude of increase in cTFH cells (from baseline to Day 8) and in IL-21 expressing CD154+CD4+ T cells (from baseline to Days 8 and 21) correlated with HAI (at Day 29) and Neut antibody (at Days 8 and 29) titers. The increase in frequency of IL-21 expressing CD154+CD4+T cells (from baseline to Day 21) correlated with memory B cell frequency (at Day 42). CONCLUSION: cTFH activation is associated with HAI and Neut responses in recipients of MF59-adjuvanted influenza A/H7N9 vaccine relative to unadjuvanted vaccine. Future studies should focus on optimizing the cTFH response and use cTFH as an early biomarker of serological response to vaccination. This trial was registered at clinicaltrials.gov, trial number NCT01938742.


Assuntos
Subtipo H7N9 do Vírus da Influenza A , Vacinas contra Influenza , Influenza Humana , Humanos , Formação de Anticorpos , Influenza Humana/prevenção & controle , Anticorpos Antivirais , Esqualeno , Polissorbatos , Adjuvantes Imunológicos , Testes de Inibição da Hemaglutinação , Anticorpos Neutralizantes , Água
4.
Infect Control Hosp Epidemiol ; 41(4): 385-390, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32933606

RESUMO

OBJECTIVE: Healthcare personnel (HCP) were recruited to provide serum samples, which were tested for antibodies against Ebola or Lassa virus to evaluate for asymptomatic seroconversion. SETTING: From 2014 to 2016, 4 patients with Ebola virus disease (EVD) and 1 patient with Lassa fever (LF) were treated in the Serious Communicable Diseases Unit (SCDU) at Emory University Hospital. Strict infection control and clinical biosafety practices were implemented to prevent nosocomial transmission of EVD or LF to HCP. PARTICIPANTS: All personnel who entered the SCDU who were required to measure their temperatures and complete a symptom questionnaire twice daily were eligible. RESULTS: No employee developed symptomatic EVD or LF. EVD and LF antibody studies were performed on sera samples from 42 HCP. The 6 participants who had received investigational vaccination with a chimpanzee adenovirus type 3 vectored Ebola glycoprotein vaccine had high antibody titers to Ebola glycoprotein, but none had a response to Ebola nucleoprotein or VP40, or a response to LF antigens. CONCLUSIONS: Patients infected with filoviruses and arenaviruses can be managed successfully without causing occupation-related symptomatic or asymptomatic infections. Meticulous attention to infection control and clinical biosafety practices by highly motivated, trained staff is critical to the safe care of patients with an infection from a special pathogen.


Assuntos
Anticorpos Antivirais/sangue , Infecção Hospitalar/sangue , Infecção Hospitalar/epidemiologia , Doença pelo Vírus Ebola/sangue , Febre Lassa/sangue , Centros Médicos Acadêmicos , Adulto , Infecção Hospitalar/prevenção & controle , Feminino , Georgia/epidemiologia , Pessoal de Saúde , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Controle de Infecções/métodos , Febre Lassa/prevenção & controle , Vírus Lassa , Masculino , Pessoa de Meia-Idade , Estados Unidos , Vacinas Virais/imunologia
5.
Vaccines (Basel) ; 8(3)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32629943

RESUMO

Human papillomavirus virus (HPV) vaccines aim to provide durable protection and are ideal to study the association of cellular with humoral responses. We assessed the duration and characteristics of immune responses provided by the quadrivalent HPV (4vHPV) vaccine in healthy female adults with or without prior exposure with type 16 and 18 HPV. In a prospective cohort, vaccine naïve females received three doses of 4vHPV vaccine and were followed for two years to assess cellular (intracellular cytokine staining, proliferation and B cell ELISpot assays) and humoral (multiplex L1/L2 viral-like particles (VLP) and M4 ELISAs) responses. Frequencies of vaccine-specific CD4+ T cells correlated with antibody responses. Higher HPV antibody titers were found at all time points in participants previously exposed to HPV, except for anti-HPV-18 at Day 187 (one week post the third vaccination). Retrospective cohorts enrolled females who had previously received two or three 4vHPV doses and tested antibody titers by M4 ELISA and pseudovirion neutralization assay along with memory B cells (MBCs). Almost all women enrolled in a retrospective cohort with two prior doses and all women enrolled in a retrospective cohort with three prior doses had sustained antibody and memory responses. Our findings indicate that HPV vaccination induces a long-lasting, robust cellular and humoral immune responses.

6.
Nat Cell Biol ; 21(2): 179-189, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30664791

RESUMO

Loss of TGF-ß tumour suppressive response is a hallmark of human cancers. As a central player in TGF-ß signal transduction, SMAD4 (also known as DPC4) is frequently mutated or deleted in gastrointestinal and pancreatic cancer. However, such genetic alterations are rare in most cancer types and the underlying mechanism for TGF-ß resistance is not understood. Here we describe a mechanism of TGF-ß resistance in ALK-positive tumours, including lymphoma, lung cancer and neuroblastoma. We demonstrate that, in ALK-positive tumours, ALK directly phosphorylates SMAD4 at Tyr 95. Phosphorylated SMAD4 is unable to bind to DNA and fails to elicit TGF-ß gene responses and tumour suppressing responses. Chemical or genetic interference of the oncogenic ALK restores TGF-ß responses in ALK-positive tumour cells. These findings reveal that SMAD4 is tyrosine-phosphorylated by an oncogenic tyrosine kinase during tumorigenesis. This suggests a mechanism by which SMAD4 is inactivated in cancers and provides guidance for targeted therapies in ALK-positive cancers.


Assuntos
Quinase do Linfoma Anaplásico/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias/genética , Proteína Smad4/genética , Fator de Crescimento Transformador beta/farmacologia , Quinase do Linfoma Anaplásico/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Perfilação da Expressão Gênica/métodos , Células HEK293 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação , Proteína Smad4/metabolismo , Transplante Heterólogo , Tirosina/genética , Tirosina/metabolismo
7.
Angew Chem Int Ed Engl ; 57(15): 3949-3953, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29437274

RESUMO

Membrane voltage is an important biophysical signal that underlies intercellular electrical communications. A fluorescent voltage indicator is presented that enables the investigation of electrical signaling at high spatial resolution. The method is built upon the site-specific modification of microbial rhodopsin proteins with organic fluorophores, resulting in a hybrid indicator scaffold that is one of the most sensitive and fastest orange-colored voltage indicators developed to date. We applied this technique to optically map electrical connectivity in cultured cells, which revealed gap junction-mediated long-range coupling that spanned over hundreds of micrometers.


Assuntos
Corantes Fluorescentes/química , Rodopsina/química , Acetabularia/metabolismo , Potenciais de Ação/fisiologia , Química Click , Condutividade Elétrica , Transferência Ressonante de Energia de Fluorescência , Junções Comunicantes/metabolismo , Células HEK293 , Humanos , Microscopia Confocal , Peptídeos/química
8.
PLoS One ; 11(10): e0163164, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27711228

RESUMO

GV-TH-01, a Phase 1 open-label trial of a DNA prime­Modified Vaccinia Ankara (MVA) boost vaccine (GOVX-B11), was undertaken in HIV infected participants on antiretroviral treatment (ART) to evaluate safety and vaccine-elicited T cell responses, and explore the ability of elicited CD8+ T cells to control viral rebound during analytical treatment interruption (TI). Nine men who began antiretroviral therapy (ART) within 18 months of seroconversion and had sustained plasma HIV-1 RNA <50 copies/mL for at least 6 months were enrolled. Median age was 38 years, median pre-ART HIV-1 RNA was 140,000 copies/ml and mean baseline CD4 count was 755/µl. Two DNA, followed by 2 MVA, inoculations were given 8 weeks apart. Eight subjects completed all vaccinations and TI. Clinical and laboratory adverse events were generally mild, with no serious or grade 4 events. Only reactogenicity events were considered related to study drug. No treatment emergent viral resistance was seen. The vaccinations did not reduce viral reservoirs and virus re-emerged in all participants during TI, with a median time to re-emergence of 4 weeks. Eight of 9 participants had CD8+ T cells that could be stimulated by vaccine-matched Gag peptides prior to vaccination. Vaccinations boosted these responses as well as eliciting previously undetected CD8+ responses. Elicited T cells did not display signs of exhaustion. During TI, temporal patterns of viral re-emergence and Gag-specific CD8+ T cell expansion suggested that vaccine-specific CD8+ T cells had been stimulated by re-emergent virus in only 2 of 8 participants. In these 2, transient decreases in viremia were associated with Gag selection in known CD8+ T cell epitopes. We hypothesize that escape mutations, already archived in the viral reservoir, plus a poor ability of CD8+ T cells to traffic to and control virus at sites of re-emergence, limited the therapeutic efficacy of the DNA/MVA vaccine. TRIAL REGISTRATION: clinicaltrials.gov NCT01378156.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/fisiologia , Imunização Secundária/métodos , Vacinação/métodos , Vacinas de DNA/imunologia , Suspensão de Tratamento , Adulto , Fármacos Anti-HIV/farmacologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Contagem de Células , Feminino , Produtos do Gene gag/metabolismo , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/efeitos dos fármacos , HIV-1/imunologia , Humanos , Imunização Secundária/efeitos adversos , Masculino , Recidiva , Segurança , Especificidade da Espécie , Vacinação/efeitos adversos , Carga Viral/efeitos dos fármacos , Carga Viral/imunologia
9.
J Biol Chem ; 289(4): 2072-83, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24324267

RESUMO

ZNF451 is a transcriptional cofactor localized to promyelocytic leukemia bodies. Here, we present evidence demonstrating that ZNF451 physically interacts with Smad3/4 and functionally inhibits TGF-ß signaling. Increased expression of ZNF451 attenuates TGF-ß-induced growth inhibitory and gene transcriptional responses, whereas depletion of ZNF451 enhances TGF-ß responses. Mechanistically, ZNF451 blocks the ability of Smad3/4 to recruit p300 in response to TGF-ß, which causes reduction of histone H3K9 acetylation on the promoters of TGF-ß target genes. Taken together, ZNF451 acts as a transcriptional corepressor for Smad3/4 and negatively regulates TGF-ß signaling.


Assuntos
Proteínas Repressoras/metabolismo , Transdução de Sinais/fisiologia , Proteína Smad3/metabolismo , Proteína Smad4/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Acetilação , Aminoaciltransferases , Proteína p300 Associada a E1A/genética , Proteína p300 Associada a E1A/metabolismo , Células HEK293 , Células HeLa , Histonas/genética , Histonas/metabolismo , Humanos , Proteínas Repressoras/genética , Proteína Smad3/genética , Proteína Smad4/genética , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/genética
10.
Hum Vaccin Immunother ; 8(11): 1654-8, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23111169

RESUMO

Here, we report on GEO-D03, a DNA vaccine that co-expresses non-infectious HIV-1 virus-like particles (VLPs) and the human cytokine, granulocyte-macrophage colony-stimulating factor (GM-CSF). The virus-like particles display the native gp160 form of the HIV-1 Envelope glycoprotein (Env) and are designed to elicit antibody against the natural form of Env on virus and virus-infected cells. The DNA-expressed HIV Gag, Pol and Env proteins also have the potential to elicit virus-specific CD4 and CD8 T cells. The purpose of the co-expressed GM-CSF is to target a cytokine that recruits, expands and differentiates macrophages and dendritic cells to the site of VLP expression. The GEO-D03 DNA vaccine is currently entered into human trials as a prime for a recombinant modified vaccinia Ankara (MVA) boost. In preclinical studies in macaques using an SIV prototype vaccine, this vaccination regimen elicited both anti-viral T cells and antibody, and provided 70% protection against acquisition during 12 weekly rectal exposures with a heterologous SIV. Higher avidity of the Env-specific Ab for the native form of the Env in the challenge virus correlated with lower likelihood of SIV infection.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , HIV-1/imunologia , Vacinas de DNA/imunologia , Animais , Citocinas/metabolismo , Humanos
11.
Immunology ; 126(3): 346-53, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18657205

RESUMO

The hallmark of effective establishment of immune memory is the long-term memory cell that persists in the absence of antigen. To explore its characteristics, we investigated the differences between a resolved successful immune response, such as after influenza (flu) vaccination, and the state of chronic infection with persistent antigen, such as with cytomegalovirus (CMV), Epstein-Barr virus (EBV) or human immunodeficiency virus (HIV), which leads to defective T-cell memory. Immunophenotypic analyses using multi-parameter flow cytometry and tetramer technology identified a unique pattern of CD26(high) expression among influenza-specific CD8(+) T cells, but not among CD8(+) T cells specific for CMV, EBV (three different epitopes) or HIV. The median percentage of CD8(+) T cells expressing CD26 was 95.5% for influenza, but for cells specific for CMV, EBV and HIV it was 10.5%, 12%-19%, and 13.2%, respectively. These findings suggest that expression of CD26(high) may be a characteristic of a memory cell. CD26(high) expression correlates with expression of CD127, a marker of memory cells. Furthermore, CD26(high) cells can produce interleukin-2. These findings offer insight into the dynamics of T-cell differentiation, and they may offer a specific marker of a successfully developed memory CD8(+) T cell, that of CD26(high). This marker has the potential to be useful in studies of immune responses to infectious agents, and to new vaccine candidates.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Dipeptidil Peptidase 4/metabolismo , Viroses/imunologia , Adulto , Biomarcadores/metabolismo , Proliferação de Células , Células Cultivadas , Doença Crônica , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Feminino , Infecções por HIV/imunologia , HIV-1/fisiologia , Herpesvirus Humano 4/fisiologia , Humanos , Memória Imunológica , Imunofenotipagem , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos/imunologia , Masculino , Latência Viral/imunologia
12.
Virology ; 343(2): 246-55, 2005 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-16185742

RESUMO

Here, we study immune responses in four DNA/MVA-vaccinated macaques following an SHIV-89.6P challenge and a subsequent CD8 cell depletion. Both post-challenge and post-depletion peaks of viremia contracted with the expansion, or re-emergence, of CD8 T cells. Post-depletion, CD8 cells expanded in the presence of higher levels of neutralizing Ab and CD4 help than post-challenge and had superior maturational characteristics as measured by expression of the anti-apoptotic protein Bcl-2, the IL-7 receptor CD127 and co-production of IFN-gamma and IL-2. Pre-challenge and pre-depletion titers of neutralizing Ab correlated inversely with peaks of viremia and directly with peaks for anti-viral CD4 cells. Thus, our results reveal CD8 cells playing a central role, and neutralizing Ab, a supporting role in SHIV-89.6P control. They also suggest a dynamic relationship between neutralizing Ab, antigen load and anti-viral CD4 cells in the maturation of high-quality anti-viral CD8 T cells.


Assuntos
Vacinas contra a AIDS/farmacologia , Linfócitos T CD8-Positivos/imunologia , Vacinas contra a SAIDS/farmacologia , Vacinas de DNA/farmacologia , Animais , Linfócitos T CD4-Positivos/imunologia , Quimera/imunologia , Produtos do Gene gag/imunologia , HIV/imunologia , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Humanos , Memória Imunológica , Interferon gama/biossíntese , Interleucina-2/biossíntese , Depleção Linfocítica , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/imunologia , Fatores de Tempo , Viremia/imunologia
13.
J Immunol ; 174(10): 6088-94, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15879103

RESUMO

Killer cell lectin-like receptor G1 (KLRG1) is one of several inhibitory killer cell lectin-like receptors expressed by NK cells and T lymphocytes, mainly CD8(+) effector/memory cells that can secrete cytokines but have poor proliferative capacity. Using multiparameter flow cytometry, we studied KLRG1 expression on CD8(+) T cells specific for epitopes of CMV, EBV, influenza, and HIV. Over 92% of CD8(+) cells specific for CMV or EBV expressed KLRG1 during the latent stage of these chronic infections. CD8(+) T cell cells specific for HIV epitopes were mostly (72-89%) KLRG1(+), even though not quite at the level of predominance noted with CMV or EBV. Lower frequency of KLRG1 expression was observed among CD8(+) cells specific for influenza (40-73%), a resolved infection without a latent stage. We further observed that CD8(+) cells expressing CD57, a marker of replicative senescence, also expressed KLRG1; however, a population of CD57(-)KLRG1(+) cells was also identified. This population may represent a "memory" phenotype, because they also expressed CD27, CD28, CCR7, and CD127. In contrast, CD57(+)KLRG1(+) cells did not express CD27, CD28, and CCR7, and expressed CD127 at a much lower frequency, indicating that they represent effector cells that are truly terminally differentiated. The combination of KLRG1 and CD57 expression might thus aid in refining functional characterization of CD8(+) T cell subsets.


Assuntos
Antígenos CD57/biossíntese , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Epitopos de Linfócito T/biossíntese , Transativadores/biossíntese , Latência Viral/imunologia , Antígenos CD57/fisiologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular/imunologia , Proliferação de Células , Citomegalovirus/imunologia , Feminino , HIV-1/imunologia , Herpesvirus Humano 4/imunologia , Humanos , Imunidade Ativa , Memória Imunológica , Imunofenotipagem , Lectinas Tipo C , Masculino , Orthomyxoviridae/imunologia , Receptores Imunológicos , Transativadores/fisiologia , Replicação Viral/imunologia
14.
Brain Res ; 1005(1-2): 21-8, 2004 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-15044060

RESUMO

We tested the hypothesis that intravenous infusion of human marrow stromal cells (hMSC) with a nitric oxide donor, (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl) aminio] diazen-1-ium-1,2-diolate (DETA/NONOate), enhances angiogenesis, neurogenesis and neurological functional recovery after stroke in rats compared to individual therapy. Experimental groups consist of rats subjected to 2 h of middle cerebral artery occlusion (MCAo) and at 24 h after MCAo intravenous injection of (n=10/group): Group 1: phosphate buffered saline (PBS 1 ml) for control. Group 2: NONOate alone (0.4 mg/kg). Group 3: hMSCs (1 x 10(6)) alone. Group 4: hMSCs (1 x 10(6)) with NONOate (0.4 mg/kg). Functional tests and immunohistochemical staining were performed. Marginal functional recovery after treatment of stroke was found with 1 x 10(6) hMSCs alone (p=0.06) and no benefit was detected with NONOate alone (0.4 mg/kg, p=0.64). However, NONOate+hMSCs in combination significantly induced functional recovery (p<0.05). Treatment using hMSC in combination with NONOate significantly increased vessel perimeter and endothelial cell proliferation compared with hMSC or NONOate alone treatment (p<0.05). Cell proliferation and neurogenesis were assessed with bromodeoxyuridine (BrdU) labeling and immunostaining for cell type-specific markers. Combination treatment promoted increased, BrdU positive cell number in the subventricular zone (SVZ), migrating neuronal doublecortin immunoreactive cells and VEGF and bFGF expression in the ischemic boundary area compared to individual treatment. The functional therapeutic enhancement of combination treatment may be attributed to increased plasticity induced by the combination of a nitric oxide donor and hMSC therapy. These data suggest that pharmacological and cellular therapy may provide an additive therapeutic benefit after stroke.


Assuntos
Transplante de Medula Óssea/métodos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/cirurgia , Neovascularização Fisiológica/fisiologia , Doadores de Óxido Nítrico/uso terapêutico , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Proteína Duplacortina , Quimioterapia Combinada , Humanos , Infarto da Artéria Cerebral Média/patologia , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Doadores de Óxido Nítrico/farmacologia , Ratos , Ratos Wistar , Células Estromais/citologia , Células Estromais/transplante
15.
J Neurosci Res ; 69(5): 687-91, 2002 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12210835

RESUMO

Treatment of traumatic brain injury (TBI) with bone marrow stromal cells (MSCs) improves functional outcome in the rat. However, the specific mechanisms by which introduced MSCs provide benefit remain to be elucidated. Currently, the ability of therapeutically transplanted MSCs to replace injured parenchymal CNS tissue appears limited at best. Tissue replacement, however, is not the only possible compensatory avenue in cell transplantation therapy. Various growth factors have been shown to mediate the repair and replacement of damaged tissue, so trophic support provided by transplanted MSCs may play a role in the treatment of damaged tissue. We therefore investigated the temporal profile of various growth factors, brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and hepatocyte growth factor (HGF), within cultures of human MSCs (hMSCs) conditioned with cerebral tissue extract from TBI. hMSCs were cultured with TBI extracts of rat brain in vitro and quantitative sandwich enzyme-linked immunosorbent assays (ELISAs) were performed. TBI-conditioned hMSCs cultures demonstrated a time-dependent increase of BDNF, NGF, VEGF, and HGF, indicating a responsive production of these growth factors by the hMSCs. The ELISA data suggest that transplanted hMSCs may provide therapeutic benefit via a responsive secretion of an array of growth factors that can foster neuroprotection and angiogenesis.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Substâncias de Crescimento/biossíntese , Células Estromais/efeitos dos fármacos , Extratos de Tecidos/farmacologia , Análise de Variância , Animais , Células da Medula Óssea/metabolismo , Química Encefálica , Lesões Encefálicas/patologia , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Fatores de Crescimento Endotelial/biossíntese , Ensaio de Imunoadsorção Enzimática , Fator 2 de Crescimento de Fibroblastos/biossíntese , Fator de Crescimento de Hepatócito/biossíntese , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Linfocinas/biossíntese , Masculino , Fator de Crescimento Neural/biossíntese , Ratos , Ratos Wistar , Células Estromais/metabolismo , Extratos de Tecidos/química , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
16.
Hematology ; 7(2): 113-7, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12186702

RESUMO

Bone marrow stromal cells (MSCs) administered intravenously are effective in reducing neurological deficits after stroke in the rodent. These cells appear to selectively migrate and express neural phenotypes in ischemic brain. To elucidate the mechanisms targeting MSC migration into the ischemic brain, we measured, using a microchemotaxis chamber, the effect of select chemotactic factors and cytokines expressed in injured brain, monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1alpha (MIP-1alpha) and interleukin-8 (IL-8), on migration of human bone marrow stromal cells (hMSCs). In addition, we investigated whether tissue extracts prepared from rat ischemic brain at various times after middle cerebral artery occlusion (MCAo) induce migration of hMSCs. Our data indicate that MCP-1, MIP-1alpha and IL-8 enhance the migration of hMSCs. Ischemic brain tissue extracts at 24, 48 h and 1 week after ischemia significantly increase hMSC migration across the membrane compared to non-ischemic tissue (p<0.05). These data indicate that hMSCs are targeted by inflammatory chemotactic agents and cytokines and that ischemic brain attracts hMSCs.


Assuntos
Isquemia Encefálica/patologia , Quimiocinas/farmacologia , Quimiotaxia/efeitos dos fármacos , Células Estromais/citologia , Animais , Células da Medula Óssea/citologia , Isquemia Encefálica/metabolismo , Quimiocina CCL2/farmacologia , Quimiocina CCL3 , Quimiocina CCL4 , Técnicas de Cocultura , Modelos Animais de Doenças , Humanos , Interleucina-8/farmacologia , Proteínas Inflamatórias de Macrófagos/farmacologia , Masculino , Comunicação Parácrina , Ratos , Ratos Wistar
17.
Neuropathology ; 22(4): 275-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12564767

RESUMO

Intravenous administration of human bone marrow stromal cells (hMSCs) after middle cerebral artery occlusion (MCAo) in rats provides functional benefit. We tested the hypothesis that these functional benefits are derived in part from hMSC production of growth and trophic factors. Quantitative sandwich enzyme-linked immunosorbent assay (ELISA) of hMSCs cultured with normal and MCAo brain extracts were performed. hMSCs cultured in supernatant derived from ischemic brain extracts increased production of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). These neurotrophins and angiogenic growth factors increased in a post-ischemia time-dependent manner. The hMSC capacity to increase expression of growth and trophic factors may be the key to the benefit provided by transplanted hMSCs in the ischemic brain.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Substâncias de Crescimento/metabolismo , Células Estromais/efeitos dos fármacos , Extratos de Tecidos/farmacologia , Animais , Células da Medula Óssea/metabolismo , Isquemia Encefálica/metabolismo , Transplante de Células , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Substâncias de Crescimento/análise , Humanos , Ratos , Células Estromais/metabolismo , Fatores de Tempo
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