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1.
Pulmonology ; 28(2): 105-112, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32561351

RESUMO

INTRODUCTION: The adipose tissue secretes adipokines and influences the release of inflammatory mediators contributing to a state of low-grade systemic inflammation that may change lung function. OBJECTIVE: To correlate levels of adipokines and inflammatory mediators with lung function in individuals with obesity and bronchial asthma symptoms. MATERIALS AND METHODS: A cross-sectional study, including women with obesity (grade II and III) with symptoms and clinical diagnosis of asthma. Anthropometric measurements (weight, height, BMI), pulmonary function test (spirometry), asthma control test questionnaire, collection of systemic inflammatory markers (blood collection) and pulmonary markers (sputum collection) were collected and were analyzed: IL-6, IL-8, TNF-α, adiponectin, resistin, leptin and C-reactive protein (CRP). The patients were stratified into two groups according to asthma control. RESULTS: 80 women were analyzed and 40% had an ACT score greater than or equal to 18 and were classified as "controlled asthma". More than half of the patients of ACT<18 score obtaining measures of FEV1, PEF and FEF25-75% below and 80% of predicted. There was a significant and negative correlation between IL-6 in the sputum with FVC and FEF25-75% in the group ACT<18 and with FVC and FEV1 in the group ACT≥18. CONCLUSIONS: Therefore, we concluded that the increase of interleukin-6 in the sputum is related to worse pulmonary function even in patients with controlled asthma, especially in the translate airway permeability measures.


Assuntos
Adipocinas , Asma , Adipocinas/metabolismo , Asma/complicações , Asma/diagnóstico , Estudos Transversais , Feminino , Humanos , Mediadores da Inflamação , Obesidade/complicações , Espirometria
2.
Phys Med Biol ; 63(23): 235024, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30511661

RESUMO

Magnetic resonance-guided high intensity focused ultrasound (MR-HIFU) is a noninvasive thermal technique that enables rapid heating of a specific area in the human body. Its clinical relevance has been proven for the treatments of soft tissue tumors, like uterine fibroids, and for the treatments of solid tumors in bone. In MR-HIFU treatment, MR-thermometry is used to monitor the temperature evolution in soft tissue. However, this technique is currently unavailable for bone tissue. Computer models can play a key role in the accurate prediction and monitoring of temperature. Here, we present a computer ray tracing model that calculates the heat production density in the focal region. This model accounts for both the propagation of shear waves and the interference between longitudinal and shear waves. The model was first compared with a finite element approach which solves the Helmholtz equation in soft tissue and the frequency-domain wave equation in bone. To obtain the temperature evolution in the focal region, the heat equation was solved using the heat production density generated by the raytracer as a heat source. Then, we investigated the role of the interaction between shear and longitudinal waves in terms of dissipated power and temperature output. The results of our model were in agreement with the results obtained by solving the Helmholtz equation and the frequency-domain wave equation, both in soft tissue and bone. Our results suggest that it is imperative to include both shear waves and their interference with longitudinal waves in the model when simulating high intensity focused ultrasound propagation in solids. In fact, when modeling HIFU treatments, omitting the interference between shear and longitudinal waves leads to an over-estimation of the temperature increase in the tissues.


Assuntos
Osso e Ossos/efeitos da radiação , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Osso e Ossos/diagnóstico por imagem , Simulação por Computador , Temperatura Alta , Humanos , Imageamento por Ressonância Magnética/métodos , Ondas Ultrassônicas/efeitos adversos
3.
Phys Med Biol ; 61(4): 1810-28, 2016 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-26854572

RESUMO

Magnetic resonance-guided high intensity focused ultrasound (MR-HIFU) has been clinically shown to be effective for palliative pain management in patients suffering from skeletal metastasis. The underlying mechanism is supposed to be periosteal denervation caused by ablative temperatures reached through ultrasound heating of the cortex. The challenge is exact temperature control during sonication as MR-based thermometry approaches for bone tissue are currently not available. Thus, in contrast to the MR-HIFU ablation of soft tissue, a thermometry feedback to the HIFU is lacking, and the treatment of bone metastasis is entirely based on temperature information acquired in the soft tissue adjacent to the bone surface. However, heating of the adjacent tissue depends on the exact sonication protocol and requires extensive modelling to estimate the actual temperature of the cortex. Here we develop a computational model to calculate the spatial temperature evolution in bone and the adjacent tissue during sonication. First, a ray-tracing technique is used to compute the heat production in each spatial point serving as a source term for the second part, where the actual temperature is calculated as a function of space and time by solving the Pennes bio-heat equation. Importantly, our model includes shear waves that arise at the bone interface as well as all geometrical considerations of transducer and bone geometry. The model was compared with a theoretical approach based on the far field approximation and an MR-HIFU experiment using a bone phantom. Furthermore, we investigated the contribution of shear waves to the heat production and resulting temperatures in bone. The temperature evolution predicted by our model was in accordance with the far field approximation and agreed well with the experimental data obtained in phantoms. Our model allows the simulation of the HIFU treatments of bone metastasis in patients and can be extended to a planning tool prior to MR-HIFU treatments.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Termometria/métodos , Neoplasias Ósseas/terapia , Ablação por Ultrassom Focalizado de Alta Intensidade/efeitos adversos , Temperatura Alta , Humanos , Imageamento por Ressonância Magnética/métodos , Sonicação/efeitos adversos
4.
Arch Virol ; 144(5): 905-19, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10416374

RESUMO

Chaperonin 10 of M. tuberculosis conferred partial or total protection against generalized foot-and-mouth disease (FMD) in guinea-pigs challenged with O1 Lausanne FMD virus. Chaperonin 10-immunized animals mounted an antibody response to the protein, one epitope of which was found in the C-terminal half. A similar recognition pattern was observed in FMD-convalescent guinea-pigs, swine and cattle. Anti-chaperonin 10 sera showed antiviral activity against FMDV-infected BHK-21 cells. There was strong evidence that early after infection these cells actively secrete their histones and that antisera to the chaperonin recognize them. The same antisera reacted with purified histones in immunoblotting. Most important, exogenously added histones abrogated the anti-viral activity of the antiserum and an anti-histone monoclonal antibody had strong antiviral activity against FMDV-infected BHK-21 cells. These results are consistent with previous reports on displacement of histones from the nuclear compartment and immune recognition of self-histones after viral infections. On the whole, they indicate that M. tuberculosis chaperonin 10 enables the immune system to react against early abnormalities of virus-infected cells; this is accomplished by antibody cross-reacting with histones released during virus infection.


Assuntos
Aphthovirus/imunologia , Chaperonina 10/uso terapêutico , Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Mycobacterium tuberculosis , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Formação de Anticorpos , Aphthovirus/patogenicidade , Bovinos , Linhagem Celular , Chaperonina 10/química , Chaperonina 10/imunologia , Cricetinae , Cobaias , Histonas/biossíntese , Histonas/imunologia , Dados de Sequência Molecular , Mycobacterium tuberculosis/imunologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/uso terapêutico , Suínos
5.
Biochim Biophys Acta ; 1403(2): 151-7, 1998 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-9630589

RESUMO

Self-tolerance, a key feature of the immune system, is still a matter of intense debate. We give here evidence for a peculiar behavior of an antiserum against Mycobacterium tuberculosis chaperonin 10 (m-Cpn10), which could have implications for the mechanism of self-recognition by antibodies against non-self. We show that this antiserum can interact in terms of both inhibition of biological activity and physical association (immunoprecipitation), with the mammalian homologue of m-Cpn10, but only if the bacterial protein is present. Several lines of evidence led us to exclude that the two proteins physically associate to form heterocomplexes: (1) the behavior of the antiserum was not shared by a monoclonal antibody against m-Cpn10; (2) a matrix selective for human Cpn10 (h-Cpn10) did not co-purify m-Cpn10; (3) the distribution pattern in non-denaturing isoelectric focusing of labeled m-Cpn10 was not altered by the presence of the unlabeled h-Cpn10. We conclude therefore that the antiserum against M. tuberculosis Cpn10 also recognizes mammalian Cpn10, with an affinity/avidity regulated by the mycobacterial protein, or by the promotion of hetero-oligomerization. This emergence of self-recognition in the presence of M. tuberculosis Cpn10 could imply a breaking of self-tolerance in situations of infection or vaccination.


Assuntos
Anticorpos Antibacterianos/imunologia , Especificidade de Anticorpos , Chaperonina 10/imunologia , Mycobacterium tuberculosis/imunologia , Tolerância a Antígenos Próprios , Animais , Autoimunidade , Reações Cruzadas , Humanos , Camundongos , Ligação Proteica , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
6.
J Pharmacol Exp Ther ; 285(1): 193-200, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9536010

RESUMO

Taking advantage of a standard assay on mouse LM cells (murine fibroblast-like cells), we found that several diaminic carbonates, a new class of organic compounds synthesized in our laboratories, were able to inhibit human tumor necrosis factor alpha (huTNFalpha)-induced cytotoxicity in a dose-dependent manner. Structure-function relationship studies indicated precise structural requirements for compounds being active as huTNFalpha inhibitors. ITF1779, one of the most active compounds in inhibiting huTNFalpha-induced cytotoxicity, was selected for further studies. In vitro experiments showed that ITF1779 inhibited not only huTNFalpha-induced cytotoxicity on LM cells but also another response of the same cells, interleukin-1-induced interleukin-6 production. Receptor-binding studies performed under nonequilibrium conditions and morphologic evidence of vacuole formation in cells treated with high concentrations of ITF1779 showed that the effects were strikingly similar to those of chloroquine, a lysosomotropic agent. Consistent with a mechanism of action of diaminic carbonates closely matching that of chloroquine are some structural similarities between the two classes of compounds, in particular their both being diprotic weak bases. Moreover, ITF1779 was shown to be active in vivo because it afforded protection against lipopolysaccharide-induced shock in mice, a systemic inflammatory response crucially dependent on tumor necrosis factoralpha production.


Assuntos
Anti-Inflamatórios/farmacologia , Butilaminas/farmacologia , Carbonatos/farmacologia , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Animais , Células Cultivadas/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Humanos , Interleucina-1/farmacologia , Interleucina-6/biossíntese , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos BALB C , Choque Séptico/induzido quimicamente , Choque Séptico/prevenção & controle , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
7.
Biochem Biophys Res Commun ; 229(2): 412-8, 1996 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-8954912

RESUMO

Cochaperonins (cpn10) assist chaperonins (cpn60) in promoting folding and assembly of other proteins. Upon expression of Mycobacterium tuberculosis cpn10 in Escherichia coli we have purified a polypeptide which, through amino acid sequencing, was identified as the endogenous E. coli 10K-S protein. Subsequent studies showed that its expression was specifically upregulated upon cloning of different members of the cpn10 family, including GroES, the E. coli cpn10. Pulse-chase experiments demonstrated that 10K-S is but one of several proteins whose expression is modulated upon cloning of cpn10. Up-regulation of 10K-S was also observed after exposure of normal cells, but not of groES- mutants, to elevated temperatures (42 degrees C). This allowed us to define 10K-S as a heat-shock protein (hsp) whose expression is dependent on the production of another hsp, GroES. Northern blot experiments showed that enhanced expression of 10K-S was consequent to increased accumulation of transcripts and that groES- mutants were devoid even of baseline levels of transcripts both at 37 degrees C and after temperature upshift. These results show that GroES, in addition to its established role in assisting protein folding may act as a transcriptional regulator and is likely to play an important role in modulating gene expression particularly in those conditions, like the stress response, in which its production is greatly enhanced.


Assuntos
Chaperonina 10/fisiologia , Transcrição Gênica/fisiologia , Sequência de Aminoácidos , Chaperonina 10/genética , Clonagem Molecular , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Dados de Sequência Molecular , Mycobacterium tuberculosis/genética
8.
Cancer Immunol Immunother ; 40(4): 213-8, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7538448

RESUMO

We investigated the different sensitivity of peripheral blood mononuclear cells (PBMC) and human T cell leukaemias (Jurkat and CEM) to an anti-CD5-momordin immunotoxin. In a short-term assay, the immunotoxin displayed different cytotoxic activity on normal and tumour cells: for leukaemic cell lines an incubation time of 72 h was necessary for the immunotoxin to reach the IC50 of 41-53 pM, compared to the 1 h sufficient for 6 pM immunotoxin to inhibit 50% of PBMC protein synthesis. In a long-term clonogenic assay (15 days), the immunotoxin demonstrated a comparable efficacy of clonogenic cell killing for both cell types. We investigated the immunotoxin internalization pathway by a flow-cytometric method and our data seem to indicate that the molecules meet a different intracellular fate in the two cell populations. It may be assumed that the low cytotoxic activity of immunotoxins on tumour cells, detected in the short-term assay, is due to inefficient delivery to their cytoplasmatic target, while a longer exposure of the cells to the immunotoxin promotes adequate intracellular distribution.


Assuntos
Antimetabólitos Antineoplásicos/farmacocinética , Antimetabólitos Antineoplásicos/toxicidade , Imunotoxinas/farmacocinética , Imunotoxinas/toxicidade , Leucemia de Células T/tratamento farmacológico , Leucemia de Células T/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , N-Glicosil Hidrolases , Proteínas de Plantas/farmacocinética , Proteínas de Plantas/toxicidade , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos CD5 , Células Cultivadas , Citometria de Fluxo , Fluoresceína-5-Isotiocianato/farmacocinética , Humanos , Líquido Intracelular/metabolismo , Leucemia de Células T/imunologia , Leucócitos Mononucleares/imunologia , Proteínas Inativadoras de Ribossomos Tipo 2 , Sensibilidade e Especificidade , Fatores de Tempo , Células Tumorais Cultivadas
9.
FEBS Lett ; 361(2-3): 211-4, 1995 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-7698325

RESUMO

We have recently reported the cloning of a cDNA coding for a stress inducible human chaperonin 10. The protein was shown to possess 100% identity with the bovine homologue and a single amino acid replacement (glycine to serine at position 52) compared to rat chaperonin 10. Here we report the heterologous expression of human chaperonin 10 in Escherichia coli, its purification and its functional characterization. The recombinant protein was purified to homogeneity as judged by different analytical techniques, and mass spectrometry analysis showed a MW of 10,801 Da in agreement with the predicted sequence. This molecular weight accounts for a protein which is not modified post-translationally. In fact, natural rat chaperonin 10 has been shown to be acetylated at the N-terminus, a feature suggested to be important for targeting and functional activity. Here we show that recombinant human chaperonin 10 is fully active in assisting the chaperonin 60 GroEL in the refolding of denatured yeast enolase, thereby showing that, at least in the present system, post-translational acetylation is not necessary for its activity.


Assuntos
Chaperonina 10/biossíntese , Proteínas Recombinantes/biossíntese , Sequência de Bases , Carcinoma Hepatocelular , Linhagem Celular , Chaperonina 10/química , Chaperonina 10/isolamento & purificação , Chaperonina 60/metabolismo , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Clonagem Molecular/métodos , Primers do DNA , Escherichia coli , Temperatura Alta , Humanos , Cinética , Neoplasias Hepáticas , Espectrometria de Massas , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Ligação Proteica , Dobramento de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Células Tumorais Cultivadas
10.
Cancer Immunol Immunother ; 40(2): 109-14, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7882380

RESUMO

Immunotoxins were prepared with a Ber-H2 (anti-CD30) monoclonal antibody and native or recombinant dianthin 30, a ribosome-inactivating protein from Dianthus caryophyllus (carnation). Both immunotoxins selectively inhibited protein synthesis by CD30+ cell lines D430B (lymphoblastoid, infected with Epstein-Barr virus), L428 and L540 (both from Hodgkin's lymphoma). IC50 values (concentrations, as dianthin, causing 50% inhibition) ranged from 324 pM to 479 pM (immunotoxin with native dianthin 30) or from 45 pM to 182 pM (immunotoxin with recombinant dianthin 30). The effect of either immunotoxin on protein synthesis by the CD30+ cell line K562 (from a chronic myeloid leukaemia) was not different from that of free dianthin (IC50 higher than nM).


Assuntos
Imunotoxinas/administração & dosagem , N-Glicosil Hidrolases/administração & dosagem , Proteínas de Plantas/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Sequência de Bases , Sistema Livre de Células , Primers do DNA/química , Humanos , Técnicas In Vitro , Antígeno Ki-1/imunologia , Dados de Sequência Molecular , Biossíntese de Proteínas , Proteínas Recombinantes , Proteínas Inativadoras de Ribossomos , Proteínas Inativadoras de Ribossomos Tipo 1 , Ribossomos/efeitos dos fármacos , Células Tumorais Cultivadas
11.
Artigo em Inglês | MEDLINE | ID: mdl-9346855

RESUMO

Dianthin 30, a ribosome inactivating protein (RIP) from Dianthus caryophyllus, has been expressed in Escherichia coli. Heterologous expression of a deletion mutant dianthin 30 delta 255-270 resulted in the production of a protein identical to carnation mature dianthin 30, including the absence at the carboxy-terminal of a putative 16 amino acid long pro-signal peptide. The production of a form of dianthin 30, which includes the pro-signal, is described as well. Both dianthin 30 delta 255-270 and dianthin 30 expressed in E. coli are mainly localized (90%) in the soluble fraction. Dianthin 30 delta 255-270 and dianthin 30 have been purified to homogeneity and were shown to inhibit protein synthesis in vitro with an IC50 of 8 and of 11 ng/ml, respectively. Secondary structure analysis, carried out by circular dichroism spectroscopy, indicated that the naturally occurring and the recombinant forms of dianthin 30 and dianthin 30 delta 255-270 possess the same secondary structure composition, accounting for an alpha + beta type architecture. RIPs as immunotoxins in clinical trial and as mitotoxins in experimental models have been extremely efficacious. In addition, growing evidence indicates their effective use as antiviral agents, including in HIV-1 infection. These data indicate the ability to produce either chemically linked or recombinant fusion proteins with dianthin 30 and cell-binding ligands for production of new reagents for clinical and experimental use.


Assuntos
Antivirais/química , Glicosídeo Hidrolases/química , Proteínas de Plantas/química , Estrutura Secundária de Proteína , Inibidores da Síntese de Proteínas/química , Dicroísmo Circular , Escherichia coli/genética , Glicosídeo Hidrolases/biossíntese , Glicosídeo Hidrolases/genética , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Inibidores da Síntese de Proteínas/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Inativadoras de Ribossomos Tipo 1 , Deleção de Sequência
12.
Biochem Biophys Res Commun ; 206(1): 260-5, 1995 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-7818529

RESUMO

Cochaperonins (cpn10) assist chaperonins (cpn60) in mediating folding of polypeptide substrates in an ATP-dependent reaction. Moreover, they have been shown to be secretory products of living cells and to perform discrete biological activities without the need to interact with cpn60. Here, we have investigated the possible existence of cellular cpn10 binding sites that could mediate such activities. For this purpose, we performed binding studies with iodinated cpn10 on whole cells and on electrophoretically separated eukaryotic cell lysates. The former studies yielded negative results, whereas in the latter binding to several proteins was detected. These proteins were identified as being histones. Binding was observed to all core histones (H2A, H2B, H3 and H4) and, although weaker, to the linker histone H1 as well. These results show that cpn10 are histone-binding proteins.


Assuntos
Chaperonina 10/metabolismo , Chaperonina 60/metabolismo , Histonas/metabolismo , Proteínas Recombinantes/metabolismo , Animais , Chaperonina 10/isolamento & purificação , Chaperonina 60/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Histonas/isolamento & purificação , Humanos , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/metabolismo , Ligação Proteica , Ratos , Ratos Endogâmicos Lew , Proteínas Recombinantes/isolamento & purificação , Timo/metabolismo
13.
Biochim Biophys Acta ; 1218(3): 478-80, 1994 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-7914093

RESUMO

We have identified a heat-shock-inducible 10 kDa protein in the human hepatoma cell line HepG2. The total RNA extracted from the heat-shocked cells was amplified by reverse transcription PCR (polymerase chain reaction) using 21 5' and 18 3' oligonucleotides of rat cpn10 (chaperonin10) cDNA as primers. Sequencing of the above PCR fragment showed a very high homology between human, bovine and rat cpn10 cDNA. The predicted amino acid sequence revealed a 100% identity with the bovine homologue.


Assuntos
Proteínas de Choque Térmico/genética , Hominidae/genética , Sequência de Aminoácidos , Animais , Bactérias/genética , Sequência de Bases , Carcinoma Hepatocelular , Bovinos/genética , Chaperonina 10 , Primers do DNA , DNA Complementar/análise , Proteínas de Choque Térmico/biossíntese , Humanos , Neoplasias Hepáticas , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Ratos/genética , Saccharomyces cerevisiae/genética , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Células Tumorais Cultivadas
14.
Hybridoma ; 13(2): 99-105, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7519581

RESUMO

Female BALB/c mice were immunized with either dianthin32 or momochin, type 1 ribosome-inactivating proteins (RIPs) derived from Dianthus charyophyllus and Momordica cochinchinensis, respectively. Five anti-dianthin32 and 6 anti-momochin secreting hybridomas were obtained by somatic fusion of lymphocytes with myeloma cell line NS0. The monoclonal antibodies (MAbs) produced were highly specific, as demonstrated by cross-reactivity assays performed with taxonomically related and unrelated type 1 RIPs, and recognized different epitopes of the antigen. The affinity constant of anti-RIPs MAbs ranged between 10(8) M-1 and 10(10) M-1.


Assuntos
Anticorpos Monoclonais/biossíntese , Proteínas de Plantas/imunologia , Ribossomos/efeitos dos fármacos , Toxinas Biológicas/imunologia , Animais , Anticorpos Monoclonais/imunologia , Afinidade de Anticorpos , Western Blotting , Reações Cruzadas/imunologia , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Feminino , Hibridomas/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Coelhos , Proteínas Inativadoras de Ribossomos Tipo 1
15.
Int J Oncol ; 4(1): 175-9, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21566909

RESUMO

RAS activation state is set by GTPase Activating Proteins (GAP) and Guanine Nucleotide Releasing Proteins (GNRP). The latter were discovered in yeast as the products of the CDC25 and SDC25 genes; two protein families with homologous catalytic domains but different structural organization exist also in mammals. We show that the C-terminal, catalytic domain of a mouse homologue of CDC25 transactivates the ras-responsive fos promoter in vivo. The increased p21ras-specific guanine nucleotide releasing activity of fibroblasts expressing CDC25Mm catalytic domain correlates with tumor induction in nude mice, suggesting that deregulation of these proteins may be important in tumor development.

16.
Cancer Res ; 53(13): 3015-21, 1993 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-7686448

RESUMO

A panel of bispecific F(ab')2 antibodies (BsAb) have been constructed for delivering the ribosome-inactivating protein saporin to human B cell lymphoma. Each derivative was prepared with specificity for saporin and CD19, CD22, CD37, or immunoglobulin. In vitro studies measuring inhibition of [3H]leucine uptake by cultured Daudi and Raji cells demonstrated that, despite all BsAb capturing saporin on the cell surface, BsAb targeting through CD22 were far more cytotoxic than those functioning via CD19, CD37, or surface immunoglobulin. This exceptional activity of the CD22-specific BsAb appears to derive from its ability to deliver and accumulate saporin inside the target cells. Further studies showed that four CD22-specific BsAb all performed with equal potency and were able to increase saporin toxicity (50% inhibitory concentration) up to 1000-fold, from 2 x 10(-7) M to 2 x 10(-10) M. Pairs of anti-CD22 BsAb which recognized different nonblocking epitopes on the saporin molecule were able to bind saporin more avidly to the target cell and, as a consequence, increased cytotoxicity by at least an additional 10-fold, resulting in 50% inhibitory concentration for protein synthesis of 2 x 10(-11) M. These results suggest that selected combinations of BsAb which bind cooperatively to a toxin and the cell surface may provide an efficient way of delivering toxins to unwanted cells in patients.


Assuntos
Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos B/imunologia , Antígenos de Neoplasias , Moléculas de Adesão Celular , Glicoproteínas/imunologia , Imunoglobulinas/imunologia , Imunotoxinas/uso terapêutico , Lectinas , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/imunologia , N-Glicosil Hidrolases , Proteínas de Plantas/administração & dosagem , Anticorpos Monoclonais , Especificidade de Anticorpos , Antígenos CD19 , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/imunologia , Morte Celular/efeitos dos fármacos , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos de Imunoglobulinas , Imunotoxinas/metabolismo , Radioisótopos do Iodo , Leucina/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas de Plantas/farmacocinética , Proteínas de Plantas/farmacologia , Proteínas Inativadoras de Ribossomos Tipo 1 , Saporinas , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico , Tetraspaninas , Trítio , Células Tumorais Cultivadas/efeitos dos fármacos
17.
Biochem Biophys Res Commun ; 192(3): 1230-7, 1993 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-8507195

RESUMO

Dianthin 30 is a ribosome inactivating protein (RIP 1) found in different tissues of the carnation (Dianthus caryophyllus). Recently we have isolated and sequenced a cDNA clone from a lambda gt11 expression library [Legname et al. (1991) Biochim. Biophys. Acta 1090, 119-122]. Here we describe specific PCR amplifications of either the full length pre-dianthin 30 or dianthin 30, the mature polypeptide lacking the 23 amino acid signal peptide. In vitro expression of both proteins in reticulocyte lysate generated products of the expected molecular weight. Moreover, the activity of both proteins has been evaluated confirming the characteristics of the natural product. A first attempt to produce recombinant dianthin 30 in Escherichia coli is described.


Assuntos
Glicosídeo Hidrolases/genética , Proteínas de Plantas/genética , Plantas/metabolismo , Precursores de Proteínas/genética , Animais , Sequência de Bases , Clonagem Molecular , DNA/genética , DNA/isolamento & purificação , Escherichia coli/genética , Biblioteca Gênica , Glicosídeo Hidrolases/metabolismo , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Proteínas de Plantas/metabolismo , Plantas/genética , Plasmídeos , Reação em Cadeia da Polimerase , Biossíntese de Proteínas , Precursores de Proteínas/metabolismo , Coelhos , Proteínas Recombinantes/metabolismo , Mapeamento por Restrição , Reticulócitos/metabolismo , Proteínas Inativadoras de Ribossomos Tipo 1
18.
Cancer Immunol Immunother ; 36(5): 346-50, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-7682894

RESUMO

An anti-CD5 monoclonal antibody (mAb) was linked to the plant toxin momordin, a type-1 ribosome-inactivating protein purified from Momordica charantia. The in vitro cytotoxicity of the immunotoxin was evaluated as the inhibition of protein and/or DNA synthesis on isolated peripheral blood mononuclear cells (PBMC) and on human T cell leukemia Jurkat. The potency of the immunotoxin on PBMC was very high (IC50 = 1 - 10 pM) and was not affected by blood components. The conjugate was also very efficient in the inhibition of the proliferative response in a mixed lymphocyte reaction (IC50 = 10 pM). Moreover, the in vitro performance of the immunotoxin compared favorably with those reported for other anti-CD5-based immunoconjugates containing ricin A chain. The in vivo activity of the immunotoxin was assessed in the model of nu/nu mice bearing Jurkat leukemia. A significant inhibition of the tumour development (80%, P < 0.01) in the animals treated with immunotoxin was observed. Taken together, the in vitro and in vivo results suggest that the anti-CD5-momordin conjugate may be useful for graft-versus-host disease therapy and potentially in the treatment of CD5-positive leukemias and lymphomas.


Assuntos
Antígenos CD/imunologia , Imunotoxinas/toxicidade , N-Glicosil Hidrolases , Proteínas de Plantas/administração & dosagem , Linfócitos T/efeitos dos fármacos , Animais , Especificidade de Anticorpos , Antígenos CD5 , DNA/biossíntese , Humanos , Imunoterapia , Leucemia de Células T/terapia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Biossíntese de Proteínas , Proteínas Inativadoras de Ribossomos Tipo 2 , Células Tumorais Cultivadas
20.
Int J Cancer Suppl ; 7: 73-7, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1428411

RESUMO

Results are presented showing the use of bispecific F(ab')2 antibodies (bsAbs) in the delivery of saporin for the treatment of 2 human B-cell malignancies. BsAbs delivering saporin through CD22, but not through CD19, were effective at inhibiting the uptake of [3H]leucine by Daudi and Raji cells. Furthermore, a combination of 2 anti-CD22 bsAbs, selected to bind simultaneously to saporin, bound saporin 20 times more avidly and inhibited protein synthesis far more efficiently than any single bsAb. In the first patient, with end-stage chronic lymphocytic leukaemia (CLL), treatment with 10 mg of saporin complexed to 100 mg of anti-CD19 bsAb over 43 days showed no therapeutic effect. In contrast, the second patient, with end-stage non-Hodgkin's lymphoma (NHL), given 5 mg of saporin complexed with a pair (50 mg) of anti-CD22 bsAbs over 15 days showed a marked clinical response, including complete clearance of tumour from the blood, clearance of ascites and shrinkage of tumour masses. Neither patient experienced any toxic side-effects, either during or after treatment. However, the second patient developed a strong anti-mouse Fab (HAMA) response 28 days after the treatment started. No anti-saporin response could be detected.


Assuntos
Anticorpos/uso terapêutico , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos B/imunologia , Antineoplásicos Fitogênicos/uso terapêutico , Moléculas de Adesão Celular/imunologia , Imunoterapia , Imunotoxinas , Lectinas , Leucemia Linfocítica Crônica de Células B/terapia , Linfoma de Células B/terapia , N-Glicosil Hidrolases , Proteínas de Plantas/uso terapêutico , Adulto , Terapia Combinada , Humanos , Leucemia Linfocítica Crônica de Células B/imunologia , Contagem de Leucócitos , Linfócitos/imunologia , Linfoma de Células B/imunologia , Masculino , Pessoa de Meia-Idade , Proteínas Inativadoras de Ribossomos Tipo 1 , Saporinas , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico
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