Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 139
Filtrar
1.
J Environ Manage ; 326(Pt B): 116784, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36450189

RESUMO

Ecosystem accounting is a statistical framework that aims to track the state of ecosystems and ecosystem services, with periodic updates. This framework follows the statistical standard of the System of Environmental Economic Accounting Ecosystem Accounting (SEEA EA). SEEA EA is composed of physical ecosystem extent, condition and ecosystem service supply-use accounts and monetary ecosystem service and asset accounts. This paper focuses on the potential use of the "Value Transfer" (VT) valuation method to produce the monetary ecosystem service accounts, taking advantage of experience with rigorous benefit transfer methods that have been developed and tested over many years in environmental economics. Although benefit transfer methods have been developed primarily for welfare analysis, the underlying techniques and advantages are directly applicable to monetary exchange values required for ecosystem accounting. The compilation of regular accounts is about to become a key area of work for the National Statistical Offices worldwide as well as for the EU Member States in particular, due to the anticipated amendment to regulation on European environmental economic accounts introducing ecosystem accounts. On this basis, accounting practitioners have voiced their concerns in a global consultation during SEEA EA revision, about three issues in particular: the lack of resources, the need for guidelines and the challenge of periodically updating the accounts. We argue that VT can facilitate empirical applications that assess ecosystem services in monetary terms, especially at national scales and in situations with limited expertise and resources available. VT is a low-cost valuation approach in line with SEEA EA requirements able to provide periodic, rigorous and consistent estimates for use in accounts. While some methodological challenges remain, it is likely that VT can help to implement SEEA EA at scale and in time to respond to the pressing need to incorporate nature into mainstream decision-making processes.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos
3.
Hum Gene Ther ; 20(5): 453-64, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19215191

RESUMO

The highly aggressive cancer syndrome of female mice carrying a p53 knockout allele and a rat HER-2/neu (Neu) transgene (BALB-p53Neu) can be prevented by a cell vaccine presenting three components: Neu, interleukin (IL)-12 production, and allogeneic major histocompatibility complex (MHC) alleles (Triplex cell vaccine). Here we tested a second-generation Triplex DNA-based vaccine (Tri-DNA), consisting of the combination of three gene components (a transmembrane-extracellular domain fragment of the Neu gene, IL-12 genes, and the H-2D(q) allogeneic MHC gene), carried by separate plasmids. The Tri-DNA vaccine was at least as effective as the Triplex cell vaccine for cancer immunoprevention, giving a similar delay in the onset of mammary cancer and complete protection from salivary cancer. Both vaccines induced anti-Neu antibodies of the murine IgG2a isotype at similar levels. The Tri-DNA vaccine gave more restricted immunostimulation, consisting of a fully helper T cell type 1 (Th1)-polarized response, with effective production of interferon (IFN)-gamma in response to the vaccine but no spontaneous production, and no induction of anti-Neu IgG3 antibodies. On the other hand, the Triplex cell vaccine induced both Th1 and Th2 cytokines, a strong increase in spontaneous IFN-gamma production, and high levels of IgG3 antibodies recognizing Neu-positive syngeneic cells. In conclusion, the Tri-DNA vaccine is as effective as Triplex cell vaccine, exploiting a more restricted immune stimulation.


Assuntos
Vacinas Anticâncer/imunologia , Interleucina-12/imunologia , Síndromes Neoplásicas Hereditárias/prevenção & controle , Receptor ErbB-2/genética , Proteína Supressora de Tumor p53/genética , Vacinas de DNA/imunologia , Animais , Citocinas/biossíntese , Citocinas/imunologia , Citotoxicidade Imunológica , Feminino , Terapia Genética , Imunoglobulina G/sangue , Imunoterapia , Interferon gama/biossíntese , Interferon gama/imunologia , Interleucina-12/metabolismo , Complexo Principal de Histocompatibilidade/imunologia , Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/patologia , Camundongos , Síndromes Neoplásicas Hereditárias/terapia , Ratos , Receptor ErbB-2/imunologia , Receptor ErbB-2/metabolismo , Glândulas Salivares/imunologia , Glândulas Salivares/patologia , Transfecção , Proteína Supressora de Tumor p53/imunologia , Proteína Supressora de Tumor p53/metabolismo
4.
Gene Ther ; 15(7): 473-83, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18273053

RESUMO

The surface phenotype CD3-NK1.1+DX5+CD11c(int)B220+GR1- has been recently ascribed to a novel subset of mouse leukocytes termed interferon (IFN)-producing killer dendritic cells (IKDCs) that shares functions with natural killer (NK) cells and DCs. Interleukin-15 (IL-15) is critical for NK cells but its relationship with IKDC remained unexplored. An expression cassette encoding human IL-15 (hIL-15) has been transferred by hydrodynamic injection into the liver of mice, resulting in transient expression of the cytokine that is detectable during the first 48 h. hIL-15 hydrodynamic gene transfer resulted in an expansion of NK cells and IKDCs. Relative expansions of IKDCs were more dramatic in the IL-15 gene-transferred hepatic tissue than in the spleen. Adoptively transferred DX5+ cells comprising both NK cells and IKDCs proliferated in response to hydrodynamic injection of hIL-15, indicating that quantitative increases are at least in part the result of proliferation from already differentiated cells. Expansion is accompanied by enhanced cytolytic activity and increased expression of TRAIL and CD137 (4-1BB), without augmenting interferon-gamma production. The effects of a single hydrodynamic injection surpassed those of two intraperitoneal doses of the recombinant protein. The novel functional link between circulating IL-15 and IKDCs opens new possibilities to study the biology and applications of this minority cell subset.


Assuntos
Terapia Genética/métodos , Interleucina-15/genética , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Fígado/imunologia , Transferência Adotiva , Animais , Citotoxicidade Imunológica , Células Dendríticas/imunologia , Citometria de Fluxo , Genes RAG-1 , Humanos , Injeções Intravenosas , Interleucina-15/metabolismo , Contagem de Linfócitos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Recombinantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/imunologia , Transfecção/métodos
5.
MAGMA ; 19(6): 313-20, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17160691

RESUMO

OBJECT: Demonstrating the feasibility of magnetic resonance imaging (MRI) at 1.5 T of ultrasmall particle iron oxide (USPIO)-antibody bound to tumor cells in vitro and in a murine xenotransplant model. METHODS: Human D430B cells or Raji Burkitt lymphoma cells were incubated in vitro with different amounts of commercially available USPIO-anti-CD20 antibodies and cell pellets were stratified in a test tube. For in vivo studies, D430B cells and Raji lymphoma cells were inoculated subcutaneously in immunodeficient mice. MRI at 1.5 T was performed with T1-weighted three-dimensional fast field echo sequences (17/4.6/13 degrees ) and T2-weighted three-dimensional fast-field echo sequences (50/12/7 degrees ). For in vivo studies MRI was performed before and 24 h after USPIO-anti-CD20 administration. RESULTS: USPIO-anti-CD20-treated D430B cells, showed a dose-dependent decrease in signal intensity (SI) on T2*-weighted images and SI enhancement on T1-weighted images in vitro. Raji cells showed lower SI changes, in accordance to the fivefold lower expression of CD20 on Raji with respect to D430B cells. In vivo 24 h after USPIO-anti-CD20 administration, both tumors showed an inhomogeneous decrease of SI on T2*-weighted images and SI enhancement on T1-weighted images. CONCLUSIONS: MRI at 1.5 T is able to detect USPIO-antibody conjugates targeting a tumor-associated antigen in vitro and in vivo.


Assuntos
Anticorpos Monoclonais , Modelos Animais de Doenças , Aumento da Imagem/métodos , Ferro , Linfoma/patologia , Imageamento por Ressonância Magnética/métodos , Óxidos , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Murinos , Antígenos CD20/imunologia , Linhagem Celular Tumoral , Meios de Contraste , Dextranos , Sistemas de Liberação de Medicamentos/métodos , Óxido Ferroso-Férrico , Linfoma/imunologia , Nanopartículas de Magnetita , Camundongos , Rituximab , Transplante Heterólogo
6.
Br J Cancer ; 90(11): 2210-8, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15150552

RESUMO

Interferon-gamma (IFN-gamma) directs T helper-1 cell differentiation and mediates antitumour effects in preclinical models. However, high-dose IFN-gamma is toxic in vivo, and IFN-gamma-transfected neuroblastoma (NB) cells secreting high amounts of the cytokine may be lost due to cell apoptosis or differentiation. Two human NB cell lines (ACN and SK-N-BE2(c)) differing as to genetic and phenotypic features were transfected with the human IFN-gamma gene and selected on the grounds of the low concentrations of IFN-gamma produced. In both IFN-gamma-transfected cell lines, autocrine and paracrine activation of IFN-gamma-mediated pathways occurred, leading to markedly reduced proliferation rate, to increased expression of surface HLA and CD40 molecules and of functional TNF binding sites. ACN/IFN-gamma cells showed a significantly delayed tumorigenicity in nude mice as compared to parental cells. ACN/IFN-gamma tumours were smaller, with extensive necrotic area as a result of a damaged and defective microvascular network. In addition, a significant reduction in the proliferation index was observed. This is the first demonstration that IFN-gamma inhibits in vivo proliferation of NB cell by acting on the tumour cell itself. This effect adds to the immunoregulatory and antiangiogenic activities operated by IFN-gamma in syngeneic tumour-bearing hosts.


Assuntos
Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Interferon gama/farmacologia , Neuroblastoma/imunologia , Neuroblastoma/patologia , Animais , Primers do DNA , Feminino , Citometria de Fluxo , Terapia Genética , Humanos , Interferon gama/biossíntese , Camundongos , Camundongos Nus , Neoplasias Experimentais , Neovascularização Patológica , Fenótipo , Receptores do Fator de Necrose Tumoral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Células Tumorais Cultivadas
7.
Gene Ther ; 11(3): 284-91, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14737088

RESUMO

IL-12 is thought to induce a cytokine cascade with antiangiogenic effects mediated by IFN-gamma and angiostatic CXCR3 chemokine ligands. Naked DNA intramuscular injection of an expression vector plasmid producing IL-12 resulted in significant, well-tolerated elevation of serum IL-12 levels. Injection of the IL-12 plasmid at least 2 days, and up to 20 days, before subcutaneous injection of matrigel with angiogenic factors resulted in strong prevention of angiogenesis in both C57/bl and nude mice. A single injection of the IL-12 plasmid contemporarily with the matrigel or 2 days after resulted in partial, statistically not significant, inhibition. Control plasmid injection did not affect either angiogenesis or angiogenesis inhibition by IL-12 protein in vivo. Angiogenesis inhibition was observed in NK cell-depleted C57/bl and nude mice as well as in IFN-gamma(-/-) and CXCR3(-/-) knockout mice, indicating that NK- and/or T-cell-initiated IFN-gamma-chemokine cascades were not involved in the angiogenesis inhibition observed in vivo. Finally, IL-12 plasmid DNA gene transfer significantly prevented the growth and vascularization of highly angiogenic KS-Imm Kaposi's sarcoma and TS/A murine mammary carcinoma tumors in nude and/or syngeneic mice. These data suggest that a preventive gene therapy approach using antiangiogenic cytokines can effectively inhibit tumor angiogenesis and KS, representing an example of angioimmunoprevention.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética/métodos , Interleucina-12/genética , Neovascularização Patológica/prevenção & controle , Sarcoma de Kaposi/irrigação sanguínea , Animais , Vetores Genéticos , Interferon gama/imunologia , Interleucina-12/imunologia , Células Matadoras Naturais/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Nus , Transplante de Neoplasias , Neovascularização Patológica/imunologia , Plasmídeos/genética , Receptores CXCR3 , Receptores de Quimiocinas/imunologia , Sarcoma de Kaposi/patologia , Sarcoma de Kaposi/terapia , Linfócitos T/imunologia
9.
Cancer Lett ; 197(1-2): 111-7, 2003 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-12880969

RESUMO

The p73 gene is a p53 homologue localized at 1p36.3, a chromosomal region frequently deleted in neuroblastoma. p73 was originally considered an oncosuppressor gene. However, it was soon realized that its mode of action did not resemble that of a classic anti-oncogene. The recent discovery of N-terminal truncated isoforms, with oncogenic properties, showed that p73 has a 'two in one' structure. Indeed, the full-length variants are strong inducers of apoptosis while the truncated isoforms inhibit the pro-apoptotic activity of p53 and of the full-length p73. This review summarizes some aspects of p73 biology with particular reference to its possible role in neuroblastoma.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Neuroblastoma/metabolismo , Proteínas Nucleares/fisiologia , Processamento Alternativo , Apoptose/fisiologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Genes Supressores de Tumor , Humanos , Neuroblastoma/genética , Neuroblastoma/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Prognóstico , Taxa de Sobrevida , Proteína Tumoral p73 , Proteínas Supressoras de Tumor
10.
J Exp Med ; 197(6): 763-75, 2003 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-12642604

RESUMO

A functional hybrid receptor associating the common gamma chain (gammac) with the granulocyte/macrophage colony-stimulating factor receptor beta (GM-CSFRbeta) chain is found in mobilized human peripheral blood (MPB) CD34+ hematopoietic progenitors, SCF/Flt3-L primed cord blood (CB) precursors (CBPr CD34+/CD56-), and CD34+ myeloid cell lines, but not in normal natural killer (NK) cells, the cytolytic NK-L cell line or nonhematopoietic cells. We demonstrated, using CD34+ TF1beta cells, which express an interleukin (IL)-15Ralpha/beta/gammac receptor, that within the hybrid receptor, the GM-CSFRbeta chain inhibits the IL-15-triggered gammac/JAK3-specific signaling controlling TF1beta cell proliferation. However, the gammac chain is part of a functional GM-CSFR, activating GM-CSF-dependent STAT5 nuclear translocation and the proliferation of TF1beta cells. The hybrid receptor is functional in normal hematopoietic progenitors in which both subunits control STAT5 activation. Finally, the parental TF1 cell line, which lacks the IL-15Rbeta chain, nevertheless expresses both a functional hybrid receptor that controls JAK3 phosphorylation and a novel IL-15alpha/gammac/TRAF2 complex that triggers nuclear factor kappaB activation. The lineage-dependent distribution and function of these receptors suggest that they are involved in hematopoiesis because they modify transduction pathways that play a major role in the differentiation of hematopoietic progenitors.


Assuntos
Antígenos CD34/metabolismo , Células-Tronco Hematopoéticas/imunologia , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Receptores de Interleucina-2/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Anticorpos Monoclonais/metabolismo , Divisão Celular/fisiologia , Linhagem Celular , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Células Matadoras Naturais/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Receptores de Interleucina-15 , Receptores de Interleucina-2/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Transdução de Sinais/fisiologia
11.
Rev. Fac. Med. Univ. Nac. Nordeste ; 21(1): 12-14, 2003. tab
Artigo em Espanhol | LILACS | ID: lil-345620

RESUMO

Se estudian 784 casos de biopsias de glándula mamaria en mujeres, realizando una correlación entre la edad de las pacientes y el diagnóstico. Las patologías encontradas en las mujeres menores de 50 años muestran una marcada tendencia a la benignidad, en cambio hay un notable incremento de patologías malignas en pacientes con más de 50 años, lo que nos lleva a concluir que hay una correlación directa entre edad y el tipo de patología mamaria que se presenta


Assuntos
Humanos , Adolescente , Adulto , Feminino , Pessoa de Meia-Idade , Doenças Mamárias , Neoplasias da Mama , Doença da Mama Fibrocística/epidemiologia , Fibroadenoma , Distribuição por Idade , Fatores Etários , Doenças Mamárias , Neoplasias da Mama , Doença da Mama Fibrocística/diagnóstico , Estudos Epidemiológicos , Fibroadenoma , Estudos Retrospectivos
13.
Gene Ther ; 8(1): 75-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11402305

RESUMO

The HER-2/neu proto-oncogene is overexpressed in 20-30% of human breast cancers and is associated with high recurrence risk. The oncogenic potential of HER-2/neu, together with its elevated expression in tumors, cell surface localization, and immunogenicity in some patients, make this oncoprotein an ideal target for immunotherapeutic approaches. To test the efficacy of immune-based strategies in eliciting an antitumor response, we used the N#202 transgenic mouse model engineered to overexpress the rat neu proto-oncogene under the control of the mouse mammary tumor virus promoter; females of this line develop spontaneous focal mammary tumors by 6 months of age. Transgenic mice immunized intramuscularly with a HER-2 cDNA ligated into the VR1012 (VICAL) expression vector under the control of the cytomegalovirus promoter developed significantly fewer spontaneous tumors as compared with mice injected with the empty vector (P < 0.0001) or not injected (P = 0.0006). However, this protection was observed only when immunization was started in 3-month-old but not in 6-month-old mice. These data suggest that the xenogeneic HER-2 DNA sequence can break immune tolerance to rat neu in transgenic N#202 mice and induce protective immunity that impairs the neu oncogene-driven progression of mammary carcinogenesis. The preventive effect achieved by our immunological approach appeared not to be based on anti-neu specific B and T cell immune attacks but was more possibly based on different mechanisms including aspecific and inflammatory immunological responses.


Assuntos
Vacinas Anticâncer , Neoplasias Mamárias Experimentais/prevenção & controle , Proteínas de Neoplasias/metabolismo , Receptor ErbB-2/metabolismo , Vacinas de DNA , Fatores Etários , Animais , Citotoxicidade Imunológica , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Esquemas de Imunização , Teste de Cultura Mista de Linfócitos , Neoplasias Mamárias Experimentais/imunologia , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/imunologia , Proto-Oncogene Mas , Ratos , Receptor ErbB-2/imunologia
14.
Tissue Antigens ; 57(2): 110-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11260505

RESUMO

We studied the constitutive and the interferon (IFN)-gamma-induced expression of HLA class I antigen heavy chain, beta2-microglobulin (beta2m), TAP-1, TAP-2 and tapasin in a panel of eleven neuroblastoma cell lines. Surface expression of HLA class I antigens was low in eight out of eight neuroblastoma cell lines bearing MYC-N amplification and/or 1p deletion, while two out of three neuroblastoma cell lines lacking these genetic alterations showed normal expression. IFN-gamma treatment restored HLA class I antigen surface expression in all neuroblastoma cell lines. Eight out of 11 neuroblastoma cell lines did not express TAP-1 mRNA and three of them also lacked TAP-2 mRNA. beta2 m mRNA was barely detectable or absent in five neuroblastoma cell lines, while tapasin mRNA was always expressed. IFN-gamma upregulated the expression of HLA class I heavy chain, beta2 m, TAP-1, TAP-2 and tapasin, as detected at mRNA or protein level. Post-transcriptional events were involved in altered TAP-1 and beta2 m expression in one peculiar neuroblastoma cell line. These data indicate that multiple mechanisms play a role in the HLA class I antigen-deficient phenotype of human neuroblastoma.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Antiporters/genética , Neoplasias Encefálicas/imunologia , Proteínas da Matriz Extracelular/genética , Antígenos de Histocompatibilidade Classe I/genética , Imunoglobulinas/genética , Proteínas do Tecido Nervoso/genética , Neuroblastoma/imunologia , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Membro 3 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/análise , Transportadores de Cassetes de Ligação de ATP/imunologia , Antígenos de Superfície/genética , Antígenos de Superfície/imunologia , Antineoplásicos/farmacologia , Antiporters/análise , Antiporters/imunologia , Western Blotting , Proteínas da Matriz Extracelular/análise , Proteínas da Matriz Extracelular/imunologia , Deleção de Genes , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/imunologia , Genes myc , Antígenos de Histocompatibilidade Classe I/análise , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Cadeias Pesadas de Imunoglobulinas/análise , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/imunologia , Imunoglobulinas/análise , Imunoglobulinas/imunologia , Interferon gama/farmacologia , Proteínas de Membrana Transportadoras , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/imunologia , RNA Mensageiro/análise , Células Tumorais Cultivadas , Microglobulina beta-2/análise , Microglobulina beta-2/genética , Microglobulina beta-2/imunologia
15.
Eur J Immunol ; 31(3): 752-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11241279

RESUMO

Human tonsillar subepithelial B cells, which are a marginal zone-equivalent B cell subset, respond readily to T-independent type 2 antigens, but not to polyclonal B cell activators in vitro. In this study, subepithelial (SE) B cells were induced to proliferate and mature into plasma cells when co-cultured with activated T cells. The response of SE B cells was not observed when co-cultures were carried out in transwell chambers or in the presence of blocking anti-LFA-1 antibodies, demonstrating the need for a close T-B cell interaction. The presence of soluble CD40 also prevented the B cell response in vitro suggesting a pivotal role of CD40-CD40 ligand interactions. The data are discussed in terms of the T cell dependence of marginal zone (MZ) B cell response and the possible existence of various MZ B cell subsets.


Assuntos
Linfócitos B/imunologia , Ativação Linfocitária , Cooperação Linfocítica , Tonsila Palatina/imunologia , Linfócitos T/imunologia , Antígenos CD40/imunologia , Células Cultivadas , Epitélio/imunologia , Humanos , Imunoglobulinas/biossíntese , Antígeno-1 Associado à Função Linfocitária/imunologia
17.
J Infect Dis ; 182(6): 1643-51, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11069235

RESUMO

The extracellular activities of the human immunodeficiency virus (HIV) transactivator protein (Tat) include induction of angiogenesis and stimulation of monocyte migration. Here it is shown that polymorphonuclear leukocytes (PMNL), mostly neutrophils, rapidly invade in response to Tat in vivo and initiate the formation of new vessels. In vitro, Tat was chemotactic for PMNL and induced calcium (Ca(2+)) mobilization. Tat proteins with inactivating substitutions in the arginine-glycine-aspartic acid or basic domain were still active in inducing PMNL migration, whereas Tat peptides mapped the migration and Ca(2+) mobilization activity to a cysteine-rich core domain, previously described as a Tat "chemokine-like" region (peptide CysL(24-51)). Tat and the CysL(24-51) peptide also induced PMNL superoxide production and the release of the angiogenic factors interleukin-8 and vascular endothelial growth factor from PMNL. CysL(24-51) did not induce endothelial cell migration but was angiogenic in vivo. These data indicate that the Tat activity on PMNL is mediated by its chemokine-like region and that PMNL recruitment by Tat is linked to angiogenesis.


Assuntos
Produtos do Gene tat/farmacologia , Neutrófilos/efeitos dos fármacos , Substituição de Aminoácidos , Animais , Arginina/genética , Ácido Aspártico/genética , Cálcio/metabolismo , Células Cultivadas , Quimiotaxia de Leucócito , Colágeno , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Fatores de Crescimento Endotelial/análise , Fatores de Crescimento Endotelial/metabolismo , Produtos do Gene tat/biossíntese , Produtos do Gene tat/genética , Glicina/genética , Humanos , Interleucina-8/análise , Interleucina-8/metabolismo , Laminina , Linfocinas/análise , Linfocinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Neovascularização Patológica/etiologia , Neutrófilos/citologia , Neutrófilos/metabolismo , Proteoglicanas , Proteínas Recombinantes/biossíntese , Superóxidos/análise , Superóxidos/metabolismo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
18.
Oncogene ; 19(45): 5153-62, 2000 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-11064452

RESUMO

There are two IL-15 isoforms and eight isoforms for the IL-15Ralpha chain whose biological role is poorly understood. Here, we have analysed the intracellular trafficking of IL-15 and IL-15Ralpha and tried to shed some light on their function(s). In IL-15/GFP CHO transfectants both IL-15 isoforms show nuclear localization. Two melanoma cell lines (MELP and MELREO) spontaneously expressing the IL-15 isoforms, display different intracellular trafficking of the IL-15/IL-15Ralpha complex. In MELP cells only IL-15Ralpha is detected inside the nucleus, whereas IL-15 and IL-15Ralpha assemble at the cell surface and are internalized. Moreover, the transducing molecule TRAF2 co-immunoprecipitates with IL-15Ralpha and may be deflected to TNFRI using anti-IL-15 blocking mAbs and TNF-alpha. By contrast, MELREO cells display IL-15Ralpha and IL-15 nuclear localization but only a partial co-localization of these molecules on the cell surface. In these cells, TRAF2 is strongly associated with IL-15Ralpha and cannot be deflected by any treatment. Since TRAF2 activates the transcription factor NF-kappaB, IL-15 through IL-15Ralpha, could have a role in the control of this pathway. Indeed, anti-IL-15 MaB inhibit the constitutive nuclear localization of NFkappaB and the phosphorylation of its inhibitor Ikappa-Balpha. Thus, IL-15Ralpha controls NF-kappaB activation, however differences in the intracellular trafficking of the IL-15 and/or IL-15Ralpha suggest a different biological role for this complex in MELP versus MELREO cells.


Assuntos
Interleucina-15/metabolismo , Melanoma/metabolismo , Receptores de Interleucina-2/metabolismo , Animais , Células CHO , Compartimento Celular , Núcleo Celular , Cricetinae , Proteínas de Fluorescência Verde , Humanos , Interleucina-15/genética , Interleucina-15/isolamento & purificação , Proteínas Luminescentes/genética , Proteínas Luminescentes/isolamento & purificação , Microscopia Confocal , NF-kappa B/metabolismo , Ligação Proteica , Sinais Direcionadores de Proteínas , Subunidades Proteicas , Transporte Proteico , Proteínas/isolamento & purificação , Receptores de Interleucina-15 , Receptores de Interleucina-2/genética , Receptores de Interleucina-2/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Fator 2 Associado a Receptor de TNF
19.
J Immunol ; 165(6): 3111-8, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10975824

RESUMO

The cooperative antitumor effects of IL-12 and IL-15 gene transfer were studied in the N592 MHC class I-negative small cell lung cancer cell line xenotransplanted in nude mice. N592 cells engineered to secrete IL-15 displayed a significantly reduced tumor growth kinetics, and a slightly reduced tumor take rate, while N592 engineered with IL-12 displayed only minor changes in their growth in nude mice. However, N592 cells producing both cytokines were completely rejected, and produced a potent local bystander effect, inducing rejection of coinjected wild-type tumor cells. N592/IL-12/IL-15 cells were completely and promptly rejected also in NK-depleted nude mice, while in granulocyte-depleted animals a slight delay in the rejection process was observed. Immunohistochemical analyses of the N592/IL-12/IL-15 tumor area in intact nude mice revealed the presence of infiltrating macrophages, granulocytes, and NK cells, and expression of inducible NO synthase and of secondary cytokines such as IL-1beta, TNF-alpha, and IFN-gamma, and at higher levels GM-CSF, macrophage-inflammatory protein-2, and monocyte chemoattractant protein-1. In NK cell-depleted nude mice, numerous macrophages and granulocytes infiltrated the tumor, and a strong expression of macrophage-inflammatory protein-2 and inducible NO synthase was also observed. Finally, macrophages cocultured with N592/IL-12/IL-15 produced NO in vitro, and inhibited tumor cell growth, further suggesting their role as effector cells in this model.


Assuntos
Carcinoma de Células Pequenas/prevenção & controle , Técnicas de Transferência de Genes , Rejeição de Enxerto/imunologia , Interleucina-12/genética , Interleucina-15/genética , Células Matadoras Naturais/imunologia , Neoplasias Pulmonares/prevenção & controle , Linfócitos T/imunologia , Adjuvantes Imunológicos/genética , Adjuvantes Imunológicos/metabolismo , Animais , Carcinoma de Células Pequenas/imunologia , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Pequenas/patologia , Divisão Celular/genética , Divisão Celular/imunologia , Técnicas de Cocultura , Citotoxicidade Imunológica , Sinergismo Farmacológico , Feminino , Regulação da Expressão Gênica/imunologia , Rejeição de Enxerto/genética , Rejeição de Enxerto/patologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Granulócitos/imunologia , Granulócitos/metabolismo , Humanos , Imuno-Histoquímica , Interferon gama/metabolismo , Interleucina-12/biossíntese , Interleucina-12/metabolismo , Interleucina-15/biossíntese , Interleucina-15/metabolismo , Leucopenia/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Depleção Linfocítica , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Nus , Transplante de Neoplasias , Óxido Nítrico/biossíntese , Baço/citologia , Baço/imunologia , Baço/metabolismo , Transfecção/imunologia , Transplante Heterólogo , Células Tumorais Cultivadas
20.
Int J Cancer ; 87(4): 574-81, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10918200

RESUMO

IL-15 is an immunostimulatory cytokine with IL-2-like activities. To exploit the potential role of IL-15 in cancer immuno-/gene therapy, we engineered murine TS/A cells with different IL-15 cDNA constructs. Significant IL-15 secretion was achieved only by the use of a modified cDNA encoding for an IL-15 pre-protein bearing the IgK light chain signal peptide. Different TS/A clones (TS/A IL-15 C6, C23, C29) producing 390 to 1,600 pg/ml biologically active IL-15 showed reduced tumorigenicity when implanted s.c. in syngeneic mice and significantly reduced metastatic potential by i.v. injection. Tumorigenicity of s.c. TS/A IL-15 was restored in animals depleted of CD8(+) lymphocytes or of natural killer cells and partially in CD4(+)-depleted mice. TS/A IL-15 cells displayed a significantly reduced growth rate by s.c. implant in nude mice. Also, >50% syngeneic animals rejecting TS/A IL-15 were resistant to a subsequent rechallenge with wild-type tumor (TS/Apc), indicating induction of protective immunity against TS/A tumor-associated antigens (TAAs). Cytolytic T lymphocyte (CTL) activity, specifically inhibited by anti-CD3 antibodies, was inducible in the splenocytes of TS/A IL-15-immunized animals by mixed lymphocyte/tumor culture (MLTC), and IFN-gamma was released in the supernatant of MLTC, mainly by CD8(+) cells. Immunohistochemistry of the TS/A IL-15 tumor area revealed the presence of an inflammatory infiltrate with predominant natural killer, macrophage, and granulocyte components and expression of IFN-gamma as a distinctive secondary cytokine. Use of TS/A IL-15 mitomycin-treated cells for therapeutic vaccination in experimental TS/A metastasis was effective in 60% of animals treated; these animals showed no metastatic tumor growth.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/imunologia , Técnicas de Transferência de Genes , Interleucina-15/genética , Interleucina-15/imunologia , Adenocarcinoma/patologia , Animais , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/uso terapêutico , Clonagem Molecular , DNA Complementar/genética , Feminino , Imunidade Inata/imunologia , Interferon gama/biossíntese , Interleucina-15/metabolismo , Células Matadoras Naturais/imunologia , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/terapia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Linfócitos T Citotóxicos/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA