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1.
Cancer Res ; 55(17): 3847-53, 1995 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-7641203

RESUMO

In addition to infiltrating inflammatory cells, tumors also produce cytokines and growth factors that may alter tumor growth, tumor immunogenicity, and the host immune response. To characterize the expression profile of human non-small cell lung cancer (NSCLC)-derived cytokines, the mRNA expression of type 1 and type 2 cytokines in five human NSCLC lines was analyzed by reverse transcriptase-PCR. Expression of interleukin 5 (IL-5) and IL-10 was demonstrated in all tumor lines evaluated, whereas IL-4 was present in three of five lines and IL-13 was present in two of five lines. In contrast, none of the tumor lines expressed IL-2 and IFN-gamma. Type 2 cytokine protein production by NSCLC lines was confirmed by immunoprecipitation and cytokine specific ELISA. Tumor-derived IL-10 secretion was significantly augmented by exogenous recombinant cytokines including IL-4 and tumor necrosis factor-alpha. To evaluate whether fresh NSCLC nodules also express a type 2 cytokine pattern, the content of type 1 and type 2 cytokines in tissue homogenates from 13 fresh NSCLC nodules and normal lung surgical specimens was assessed. Human NSCLC nodules contain significantly more type 2 cytokines than does normal lung tissue when corrected for total protein concentration. To identify the cellular source of type 2 cytokine production in tumor nodules, immunohistology was performed on sections from 5 lung squamous cell carcinomas and 5 adenocarcinomas. All of the specimens revealed positive staining for type 2 cytokines within tumor cells. In summary, we report that human NSCLC cells produce type 2 cytokines both in situ and in vitro, which may play an active immunoregulatory role in the lung cancer microenvironment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Interleucina-10/metabolismo , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Interleucina-5/metabolismo , Neoplasias Pulmonares/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas/imunologia , Humanos , Imunidade Celular , Neoplasias Pulmonares/imunologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas
2.
Cancer Res ; 58(6): 1208-16, 1998 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9515807

RESUMO

Tumor-derived prostaglandin E2 (PGE2) modifies cytokine balance and inhibits host immunity. We hypothesized that a high level of PGE2 production by lung tumor cells is dependent on tumor cyclooxygenase (COX)-2 expression. We found that PGE2 production by A549 non-small cell lung cancer (NSCLC) cells was elevated up to 50-fold in response to interleukin (IL)-1beta. Reversal of IL-1beta-induced PGE2 production in A549 cells was achieved by specific pharmacological or antisense oligonucleotide inhibition of COX-2 activity or expression. In contrast, specific COX-1 inhibition was not effective. Consistent with these findings, IL-1beta induced COX-2 mRNA expression and protein production in A549 cells. Specific inhibition of COX-2 abrogated the capacity of IL-1beta-stimulated A549 cells to induce IL-10 in lymphocytes and macrophages. Furthermore, specific inhibition of A549 COX-2 reversed the tumor-derived PGE2-dependent inhibition of macrophage IL-12 production when whole blood was cultured in tumor supernatants. Our results indicate that lung tumor-derived PGE2 plays a pivotal role in promoting lymphocyte and macrophage IL-10 induction while simultaneously inhibiting macrophage IL-12 production. Immunohistochemistry of human NSCLC tissues obtained from lung cancer resection specimens revealed cytoplasmic staining for COX-2 within tumor cells. This is the first description of functional COX-2 expression by NSCLC cells and the definition of a pathway whereby tumor COX-2 expression and a high level of PGE2 production mediate profound alteration in cytokine balance in the lung cancer microenvironment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/enzimologia , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Interleucina-1/farmacologia , Isoenzimas/metabolismo , Neoplasias Pulmonares/enzimologia , Linfócitos/metabolismo , Macrófagos/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Adenocarcinoma/enzimologia , Carcinoma de Células Escamosas/enzimologia , Ciclo-Oxigenase 2 , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas Imunológicas , Isoenzimas/genética , Linfócitos/enzimologia , Macrófagos/enzimologia , Proteínas de Membrana , Oligonucleotídeos Antissenso/farmacologia , Prostaglandina-Endoperóxido Sintases/genética , Células Tumorais Cultivadas , Regulação para Cima
3.
Endocrinology ; 101(3): 849-57, 1977 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-891468

RESUMO

The effects of estrogen on plasma vitellogenin have been studied in the cockerel by immunoprecipitation techniques using an antiserum prepared against the egg yolk phosphoprotein, phosvitin. The antiserum gave precipitin lines of complete identity to phosvitin and to vitellogenin which was isolated from hen plasma by DEAE-cellulose chromatography and by affinity chromatography using anti-phosvitin coupled to Sepharose 4B. The cross-reactivity of vitellogenin and phosvitin adds support to the concept that plasma vitellogenin is the precursor phosphoprotein of egg yolk phosvitin. In the three-week old cockerel, anti-phosvitin produced no detectable immunoprecipitate in the plasma. However, after a single sc injection of diethylstilbestrol (2.5 mg), plasma vitellogenin levels began to increase at 4 h and reached a maximum 20-30 h after hormone administration. The increase in plasma levels of triglyceride paralleled those of vitellogenin. These studies suggest that there is no significant time lag in the estrogenic induction of plasma vitellogenesis in the cockerel, the longer lag periods observed by other investigators may be a function of the sensitivity of the assays used for detecting vitellogenin.


Assuntos
Dietilestilbestrol/farmacologia , Proteínas do Ovo/imunologia , Lipoproteínas/sangue , Fosvitina/imunologia , Vitelogeninas/sangue , Aminoácidos/análise , Animais , Complexo Antígeno-Anticorpo , Galinhas , Reações Cruzadas , Feminino , Glicerídeos/sangue , Masculino , Fosvitina/isolamento & purificação , Vitelogeninas/imunologia
4.
Magn Reson Imaging ; 8(6): 767-70, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2266803

RESUMO

Optimal control methods have been recently introduced to improve the design of selective radio frequency pulses and several optimized selective pulses that can produce excellent slice profiles have been reported. These pulses usually require high peak rf amplitudes to implement and thus can not be widely utilized because of the limitations of the specific absorption rate and the rf power amplifier of a clinical system. We have a Siemens 1.5 T MRI clinical system. Several pulse files which consist of the bandwidth matched 90 degrees and 180 degrees selective pulses are provided. Some of these can produce excellent slice profiles. However, they can only be used in the pulse sequences with the pulse length of 5.12 msec. The purpose of this paper is to improve the slice profiles produced by the pulse file in the pulse sequences with the shorter 2.56 msec pulse length. A pulse file optimized by the conjugate gradient method is proposed to substitute the 2.56 msec Siemens pulse file. Our experimental results confirm that the slice profiles and images are improved by the optimized pulse file with a lower peak voltage. The proposed pulse file can also be applied in other clinical MRI systems.


Assuntos
Imageamento por Ressonância Magnética/métodos
7.
Magn Reson Med ; 16(1): 166-72, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2255236

RESUMO

In magnetic resonance imaging, low frequency components can be allowed to saturate the analog to digital converter to reduce the quantization noise. These components can be estimated using least squares error estimation based low frequency restoration methods or the iterative Gerchberg-Papoulis algorithm. In this paper, we show the relationship between the closed form estimation methods and the iterative algorithm, propose a method for improving the speed of iteration, and discuss the advantages and disadvantages of two types of methods.


Assuntos
Algoritmos , Imageamento por Ressonância Magnética , Conversão Análogo-Digital , Análise de Fourier , Humanos , Modelos Teóricos
8.
Magn Reson Med ; 5(5): 417-33, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3431402

RESUMO

We have introduced the selective Fourier transform technique for spectral localization. This technique allows the acquisition of a high-resolution spectrum from a selectable location with control over the shape and size of the spatial response function. The shape and size of the spatial response are defined during data acquisition and the location is selectable through processing after the data acquisition is complete. The technique uses pulsed-field-gradient phase encoding to define the spatial coordinates. In this paper the theoretical basis of the selective Fourier transform technique is developed and experimental results are presented, including comparisons of spectral localization using either the selective Fourier transform method or conventional multidimensional Fourier transform chemical-shift imaging.


Assuntos
Análise de Fourier , Espectroscopia de Ressonância Magnética , Matemática , Modelos Teóricos , Análise Espectral
9.
J Immunol ; 157(12): 5512-20, 1996 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8955201

RESUMO

Studies suggest that IL-10 may contribute to tumor-associated immunosuppression. In the current study we evaluated the capacity of human non-small cell lung cancer (NSCLC) cell lines to induce PBL IL-10 production. We observed a 10- to 100-fold increase in human PBL IL-10 production following exposure to NSCLC cell supernatants. The tumor-induced increase in PBL IL-10 production was partially blocked by pretreatment of the tumors with the PG inhibitor indomethacin. NSCLC lines were found to constitutively produce PGE2. Exogenous PGE2 also induced PBL IL-10 production in a dose- and time-dependent manner. Both PGE2 and NSCLC supernatant-induced PBL IL-10 production were due to an increase in the IL-10 mRNA transcriptional rate. To evaluate the significance of tumor-induced lymphocyte IL-10 production, the capacity of PBL to produce IFN-gamma during culture in tumor supernatants was assessed in the presence of specific anti-IL-10 mAb. We found enhanced PBL IFN-gamma production following anti-IL-10 treatment. These in vitro studies imply that NSCLC-induced PBL IL-10 production may serve to shift the Th1/Th2 cytokine axis at the tumor site and thus inhibit cell-mediated anti-tumor immune responses. These findings identify a mechanism by which lung cancer cells may escape host immune surveillance. We conclude that NSCLC-derived soluble mediators, including PGs, may play an immunoregulatory role through induction of lymphocyte IL-10 production.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Dinoprostona/imunologia , Interleucina-10/biossíntese , Neoplasias Pulmonares/imunologia , Proteína Quinase Tipo II Dependente de AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Inibidores de Ciclo-Oxigenase/farmacologia , Inibidores Enzimáticos/farmacologia , Expressão Gênica , Humanos , Indometacina/farmacologia , Interferon gama/biossíntese , Interleucina-10/genética , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/fisiologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/fisiologia , Transdução de Sinais , Transcrição Gênica , Células Tumorais Cultivadas
10.
Magn Reson Med ; 21(2): 320-6, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1745132

RESUMO

Chemical-shift selective imaging with an improved selective presaturation pulse can be used to suppress the fat signal uniformly across the entire abdominal cavity. The required magnetic field homogeneity is no higher than for a routine diagnostic scan. Therefore, no extra setup time for shimming is needed. The technique has been implemented on our clinical system for routine fat suppression scans.


Assuntos
Abdome/anatomia & histologia , Tecido Adiposo , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Pelve/anatomia & histologia , Humanos , Aumento da Imagem/normas
11.
Magn Reson Med ; 16(2): 335-41, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2266851

RESUMO

The reconstruction of two-dimensional spatial images with 0.5-mm resolution using radiofrequency gradients generated by an NMR coil system rotated about the sample is demonstrated for 23Na. The method retains chemical shift, should be capable of mapping T1 and T2 information, and might offer sensitivity advantages for nuclides with short T2.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Humanos , Modelos Estruturais , Sódio
12.
Cell Immunol ; 172(2): 217-23, 1996 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8964083

RESUMO

Cocaine has multiple immunomodulatory effects, including the ability to influence cytokine release in immunoeffector cells. Little is known, however, regarding the effects of cocaine on cytokine production by human peripheral blood lymphocytes (PBL). The effect of cocaine on PBL cytokine profiles and the molecular mechanisms responsible for the modulation of cytokine mRNA expression were investigated. To evaluate the effects of cocaine on cytokine production, conditioned supernatant from IL-2-stimulated PBL was evaluated by cytokine-specific ELISA (IL-4, IL-5, IL-8, IL-10, IFN-gamma, and TGF-beta) following in vitro cocaine exposure. Cocaine abrogated the IL-2-induced production of IFN-gamma and IL-8 in a dose-responsive manner. Cocaine also decreased PBL IFN-gamma and IL-8 mRNA expression as determined by Northern blot and slot blot analysis. Cocaine did not affect the stability of the IFN-gamma and IL-8 mRNA. Nuclear run-on assays revealed that cocaine down-regulated the rate of IFN-gamma and IL-8 transcription. These findings suggest that the immunomodulatory effects of cocaine may be mediated, in part, by modification of lymphocyte cytokine production.


Assuntos
Cocaína/farmacologia , Regulação para Baixo/imunologia , Interferon gama/biossíntese , Interleucina-2/farmacologia , Interleucina-8/biossíntese , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Humanos , Interferon gama/antagonistas & inibidores , Interferon gama/genética , Interleucina-8/antagonistas & inibidores , Interleucina-8/genética , Ativação Linfocitária/efeitos dos fármacos , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/biossíntese , RNA Mensageiro/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/imunologia
13.
Cell Immunol ; 181(1): 38-43, 1997 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-9344494

RESUMO

Cocaine use is associated with modulation of a broad range of biological functions including the capacity to influence cytokine production in murine and human immunoeffector cells. Little is known, however, regarding the effects of cocaine on endothelial cell cytokine production. Because the vascular endothelium actively participates in acute and chronic inflammatory responses and interleukin-8 (IL-8) is one of the key cytokines involved in the inflammatory process, modification of the production of IL-8 by vascular endothelial cells may interfere with the host response to infection or tissue injury. We investigated the effect of cocaine on endothelial cell IL-8 production. Conditioned supernatant from EA.hy 926 cells were evaluated by ELISA following in vitro cocaine exposure. Cocaine decreased IL-8 production in a dose-responsive manner, and this reduction correlated with down-regulation of IL-8 mRNA expression. Cocaine also increased the production of TGF-beta by EA.hy 926 cells and anti-TGF-beta abrogated the cocaine-mediated decrement of IL-8 production, indicating that cocaine down-regulates endothelial IL-8 production by increasing TGF-beta. Our findings suggest that the immunomodulatory effects of cocaine may be mediated, in part, by modification of endothelial-derived cytokine production.


Assuntos
Cocaína/farmacologia , Endotélio Vascular/imunologia , Interleucina-8/biossíntese , Fator de Crescimento Transformador beta/imunologia , Vasoconstritores/farmacologia , Linhagem Celular , Meios de Cultivo Condicionados , Endotélio Vascular/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo
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