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1.
J Exp Med ; 175(5): 1207-12, 1992 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1569394

RESUMO

The Jarisch-Herxheimer Reaction (J-HR) is a clinical syndrome occurring soon after the first adequate dose of an antimicrobial drug to treat infectious diseases such as Lyme disease, syphilis, and relapsing fever. Previous attempts to identify factors mediating this reaction, that may cause death, have been unsuccessful. We conducted a prospective trial in Addis Ababa, Ethiopia on 17 patients treated with penicillin for proven louse-borne relapsing fever due to Borrelia recurrentis to evaluate the association of symptoms with plasma levels of tumor necrosis factor (TNF), interleukins 6, and 8 (IL-6 and -8). 14 of the 17 (82%) patients experienced a typical J-HR consisting of rigors, a rise in body temperature (1.06 +/- 0.2 degrees C) peaking at 2 h, leukopenia (7.4 +/- 0.6 x 10(-3) cells/mm3) at 4 h, a slight decrease, and then rise of mean arterial blood pressure. Spirochetes were cleared from blood in 5 +/- 1 h after penicillin. There were no fatalities, but constitutional symptoms were severe during J-HR. Plasma TNF, IL-6, and -8 were raised in several patients on admission, but a seven-, six-, and fourfold elevation of these plasma cytokine concentrations over admission levels was detected, respectively, occurring in transient form coincidental with observed pathophysiological changes of J-HR. Elevated plasma cytokine levels were not detected in the three patients who did not suffer J-HR. We conclude that the severe pathophysiological changes characterizing the J-HR occurring on penicillin treatment of louse-borne relapsing fever are closely associated with transient elevation of plasma TNF, IL-6, and -8 concentrations.


Assuntos
Interleucina-6/sangue , Interleucina-8/sangue , Febre Recorrente/sangue , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Humanos , Cinética , Masculino , Febre Recorrente/fisiopatologia
2.
Cell Death Differ ; 15(4): 751-61, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18219321

RESUMO

Activation of the proapoptotic receptor death receptor5 (DR5) in various cancer cells triggers programmed cell death through the extrinsic pathway. We have generated a fully human monoclonal antibody (Apomab) that induces tumor cell apoptosis through DR5 and investigated the structural features of its interaction with DR5. Biochemical studies showed that Apomab binds DR5 tightly and selectively. X-ray crystallographic analysis of the complex between the Apomab Fab fragment and the DR5 ectodomain revealed an interaction epitope that partially overlaps with both regions of the Apo2 ligand/tumor necrosis factor-related apoptosis-inducing ligand binding site. Apomab induced DR5 clustering at the cell surface and stimulated a death-inducing signaling complex containing the adaptor molecule Fas-associated death domain and the apoptosis-initiating protease caspase-8. Fc crosslinking further augmented Apomab's proapoptotic activity. In vitro, Apomab triggered apoptosis in cancer cells, while sparing normal hepatocytes even upon anti-Fc crosslinking. In vivo, Apomab exerted potent antitumor activity as a single agent or in combination with chemotherapy in xenograft models, including those based on colorectal, non-small cell lung and pancreatic cancer cell lines. These results provide structural and functional insight into the interaction of Apomab with DR5 and support further investigation of this antibody for cancer therapy.


Assuntos
Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Experimentais/tratamento farmacológico , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/agonistas , Animais , Anticorpos Monoclonais/química , Afinidade de Anticorpos , Especificidade de Anticorpos , Antineoplásicos/química , Antineoplásicos/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sítios de Ligação de Anticorpos , Caspase 8/metabolismo , Linhagem Celular Tumoral , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Mapeamento de Epitopos , Proteína de Domínio de Morte Associada a Fas/metabolismo , Feminino , Humanos , Camundongos , Camundongos Nus , Modelos Moleculares , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Ligação Proteica , Conformação Proteica , Agregação de Receptores/efeitos dos fármacos , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/química , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
3.
J Clin Invest ; 90(5): 2123-9, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1331181

RESUMO

The hydroxyl radical (OH.) scavenger dimethyl sulfoxide (DMSO) was found to dose-dependently inhibit interleukin 8 (IL-8) production in LPS-stimulated human whole blood. At a concentration of 1% (vol/vol), DMSO blocked IL-8 release by approximately 90% in the presence of 1 microgram/ml LPS at a 24-h time point, but did not affect cell viability or reduce the production of tumor necrosis factor (TNF), interleukin 6, or interleukin-1 beta (IL-1 beta). DMSO was found to directly inhibit IL-8 expression at the level of transcription. Furthermore, this effect was not LPS-specific, in that IL-8 production was reduced by DMSO to a similar extent upon stimulation of blood with phytohemagglutinin, aggregated immune complexes, TNF, or IL-1 beta. Other oxygen radical scavengers that have been shown to inhibit OH.-dependent reactions (dimethyl thiourea, thiourea, mannitol, and ethanol) also inhibited IL-8 production. Conversely, addition of H2O2 caused a dose-dependent stimulation of IL-8 release. These results provide evidence that reactive oxygen metabolites play an important role in the regulation of IL-8 production and suggest that reduction of IL-8 release may contribute to the beneficial effects of antioxidants in experimental models of inflammation and ischemia/reperfusion injury.


Assuntos
Sangue/metabolismo , Dimetil Sulfóxido/farmacologia , Sequestradores de Radicais Livres , Interleucina-8/biossíntese , Humanos , Peróxido de Hidrogênio/farmacologia , Hidróxidos , Radical Hidroxila , Técnicas In Vitro , Lipopolissacarídeos , Masculino , Fator de Necrose Tumoral alfa/biossíntese
4.
J Clin Invest ; 89(5): 1551-7, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1533231

RESUMO

The present study was undertaken to evaluate the extent to which an endogenous interleukin-1 (IL-1) response contributes to the hemodynamic and metabolic consequences of sublethal endotoxemia or lethal Gram-negative septic shock. Young, healthy baboons received either a sublethal dose of lipopolysaccharide (LPS) or an LD100 of live Escherichia coli bacteria, and one half of the animals in each group were continuously infused with IL-1 receptor antagonist (IL-1ra). Plasma IL-1 beta was not detected in this model of endotoxemia. Administration of IL-1ra had only minimal effects on the modest hemodynamic and metabolic responses to sublethal endotoxemia, and did not attenuate the plasma cytokine response. In contrast, high circulating levels of IL-1 beta (range 300-800 pg/ml) were seen during lethal E. coli septic shock. IL-1ra treatment significantly attenuated the decrease in mean arterial blood pressure (MAP) (from -72 +/- 8 to -43 +/- 6 mm Hg; P less than 0.05) and cardiac output (from -0.81 +/- 0.17 to -0.48 +/- 0.15 liter/min; P less than 0.05), and significantly improved survival from 43 to 100% at 24 h (P less than 0.05). The plasma IL-1 beta and IL-6 responses to lethal E. coli septic shock were also significantly diminished by IL-1ra treatment (P less than 0.05), whereas tumor necrosis factor-alpha (TNF alpha) concentrations were unaffected. We conclude that an exaggerated systemic IL-1 beta response is characteristic of lethal E. coli septic shock, and contributes significantly to the hemodynamic and metabolic consequences of E. coli septic shock. IL-1ra can significantly attenuate the cytokine cascade and improve survival.


Assuntos
Hemodinâmica/efeitos dos fármacos , Proteínas/farmacologia , Receptores Imunológicos/antagonistas & inibidores , Choque Séptico/fisiopatologia , Sialoglicoproteínas , Animais , Endotoxinas/sangue , Escherichia coli , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Papio , Receptores de Interleucina-1 , Fator de Necrose Tumoral alfa/metabolismo
5.
J Clin Invest ; 104(2): 155-62, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10411544

RESUMO

TNF and Fas ligand induce apoptosis in tumor cells; however, their severe toxicity toward normal tissues hampers their application to cancer therapy. Apo2 ligand (Apo2L, or TRAIL) is a related molecule that triggers tumor cell apoptosis. Apo2L mRNA is expressed in many tissues, suggesting that the ligand may be nontoxic to normal cells. To investigate Apo2L's therapeutic potential, we generated in bacteria a potently active soluble version of the native human protein. Several normal cell types were resistant in vitro to apoptosis induction by Apo2L. Repeated intravenous injections of Apo2L in nonhuman primates did not cause detectable toxicity to tissues and organs examined. Apo2L exerted cytostatic or cytotoxic effects in vitro on 32 of 39 cell lines from colon, lung, breast, kidney, brain, and skin cancer. Treatment of athymic mice with Apo2L shortly after tumor xenograft injection markedly reduced tumor incidence. Apo2L treatment of mice bearing solid tumors induced tumor cell apoptosis, suppressed tumor progression, and improved survival. Apo2L cooperated synergistically with the chemotherapeutic drugs 5-fluorouracil or CPT-11, causing substantial tumor regression or complete tumor ablation. Thus, Apo2L may have potent anticancer activity without significant toxicity toward normal tissues.


Assuntos
Antineoplásicos/farmacologia , Glicoproteínas de Membrana/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose , Fluoruracila/farmacologia , Humanos , Ligantes , Macaca fascicularis , Glicoproteínas de Membrana/toxicidade , Camundongos , Camundongos Nus , NF-kappa B/metabolismo , Neoplasias Experimentais/tratamento farmacológico , Papio , Proteínas Recombinantes/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/toxicidade
7.
Protein Sci ; 6(3): 609-17, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9070443

RESUMO

Covalent single-chain dimers of the chemokine interleukin-8 (IL-8) have been designed to mimic the dimeric form of IL-8 in solution and facilitate the production of heterodimer variants of IL-8. Physical studies indicated that use of a simple peptide linker to join two subunits, while allowing receptor binding and activation, led to self-association of the tethered dimers. However, addition of a single disulfide crosslink between the tethered subunits prevented this multimer from forming, yielding a species of dimer molecular weight. Crosslinked single-chain dimers bind to both IL-8 neutrophil receptors CXCR1 and CXCR2 as well as to DARC, as does a double disulfide-linked dimer with no peptide linker. In addition, neutrophil response to these dimers as measured by chemotaxis or beta-glucuronidase release is similar to that elicited by wild-type IL-8, providing evidence that the dissociation of the dimeric species is not required for these biologically relevant activities. Finally, through construction of single-chain heterodimer mutants, we show that only the first subunit's ELR motif is the single-chain variants.


Assuntos
Antígenos CD/metabolismo , Interleucina-8/metabolismo , Receptores de Interleucina/metabolismo , Biopolímeros , Interleucina-8/química , Modelos Moleculares , Conformação Proteica , Receptores de Interleucina-8A , Receptores de Interleucina-8B
8.
J Immunol Methods ; 245(1-2): 79-89, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11042285

RESUMO

Given the increasing incidence of methicillin resistant Staphylococcus aureus (MRSA) and the recent emergence of MRSA with a reduced susceptibility to vancomycin, alternative approaches to the treatment of infection are of increasing relevance. The purpose of these studies was to evaluate the effect of IFN-gamma on the ability of white blood cells to kill S. aureus and to develop a simpler, higher throughput bacterial killing assay. Using a methicillin sensitive clinical isolate of S. aureus, a clinical isolate of MRSA, and a commercially available strain of MRSA, studies were conducted using a killing assay in which the bacteria were added directly into whole blood. The viability of the bacteria in samples harvested at various time points was then evaluated both by the classic CFU assay and by a new assay using alamarBlue. In the latter method, serially diluted samples and a standard curve containing known concentrations of bacteria were placed on 96-well plates, and alamarBlue was added. Fluorescence readings were taken, and the viability of the bacteria in the samples was calculated using the standard curve. The results of these studies demonstrated that the CFU and alamarBlue methods yielded equivalent detection of bacteria diluted in buffer. For samples incubated in whole blood, however, the alamarBlue method tended to yield lower viabilities than the CFU method due to the emergence of a slower growing subpopulation of S. aureus upon incubation in the blood matrix. A significant increase in bacterial killing was observed upon pretreatment of whole blood for 24 h with 5 or 25 ng/ml IFN-gamma. This increase in killing was detected equivalently by the CFU and alamarBlue methods. In summary, these studies describe a method that allows for the higher throughput analysis of the effects of immunomodulators on bacterial killing.


Assuntos
Atividade Bactericida do Sangue/efeitos dos fármacos , Contagem de Colônia Microbiana/métodos , Corantes , Interferon gama/farmacologia , Oxazinas , Staphylococcus aureus/imunologia , Xantenos , Atividade Bactericida do Sangue/imunologia , Humanos , Técnicas In Vitro , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Masculino , Resistência a Meticilina , Receptores de IgG/metabolismo , Proteínas Recombinantes , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Fator de Necrose Tumoral alfa/biossíntese
9.
Int J Pharm ; 198(1): 83-95, 2000 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-10722953

RESUMO

By covalently attaching biocompatible polyethylene-glycol (PEG) groups to epsilon-amino groups of the F(ab')(2) form of a humanized anti-interleukin-8 (anti-IL-8) antibody, we sought to decrease the in vivo clearance rate to give a potentially more clinically acceptable therapeutic. The in vivo clearance was modulated by changing the hydrodynamic size of the PEGylated antibody fragments. To achieve significant increases in the hydrodynamic size with minimal loss in bioactivity, high molecular weight linear or branched PEG molecules were used. Modification involved N-hydroxy-succinamide reaction of the PEGs with primary amines (lysines and/or the N-terminus) of the anti-IL-8 F(ab')(2). The process of adding up to four linear 20 kDa PEG, or up to two branched 40 kDa PEG, gave reproducible distribution of products. The components with uniform size (as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis) were purified by a single-step ion-exchange high-performance liquid chromatography and showed no significant loss of biological activity in ligand binding and cell-based assays. Addition of a single branched 40 kDa PEG to a F(ab')(2) (molecular weight (MW)=1.6 million Da) or up to two 40 kDa branched PEG (MW=1.9 million Da) increased the serum half-life to 48 h as compared with the unPEGylated F(ab')(2) with a half-life of 8.5 h. This study shows that by attaching high molecular weight PEGs at a one or two sites, bioactive antibody fragments can be made reproducibly with sizes tailored to achieve the desired pharmacokinetics.


Assuntos
Anticorpos Bloqueadores/metabolismo , Fragmentos Fab das Imunoglobulinas/metabolismo , Interleucina-8/imunologia , Aminas/química , Animais , Anticorpos Bloqueadores/química , Antígenos CD/efeitos dos fármacos , Área Sob a Curva , Quimiotaxia de Leucócito/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Fragmentos Fab das Imunoglobulinas/química , Masculino , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Polietilenoglicóis/química , Coelhos , Receptores de Interleucina/efeitos dos fármacos , Receptores de Interleucina-8A , Espectrofotometria Ultravioleta , Tensoativos/química
12.
Immunol Invest ; 20(1): 89-97, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2055605

RESUMO

A sensitive sandwich enzyme-linked immunosorbent assay (ELISA) was developed for interleukin-8 (IL-8), a neutrophil chemoattractant and activator. A polyclonal antibody to recombinant human IL-8 was raised in rabbits, and the IgG was isolated from the antisera using a protein A column. Native and biotinylated forms of this antibody served as the capture antibody and developing antibody for the ELISA, respectively, and avidin-conjugated horse radish peroxidase provided the means for enzymatic color development. The lower limit of sensitivity for the assay was found to be 84 +/- 20 pg/ml IL-8 (mean +/- SD for 10 determinations). An inter-assay variability of 15-29% and an intra-assay variability of 12% were observed. The assay was able to detect IL-8 when the samples were prepared in either normal saline, RPMI, or human plasma. The development of this rapid, sensitive assay should provide a means to more fully evaluate the role of this cytokine in diverse disease states.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Interleucina-8/análise , Animais , Humanos , Técnicas Imunoenzimáticas , Interleucina-8/imunologia , Coelhos , Proteínas Recombinantes , Reprodutibilidade dos Testes
13.
Biochem Biophys Res Commun ; 174(1): 18-24, 1991 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1989598

RESUMO

While the production of tumor necrosis factor (TNF) and interleukin-6 (IL-6) in septic shock and other inflammatory states is well established, the role of interleukin-8 (IL-8), a recently described neutrophil chemoattractant and activator, has yet to be fully elucidated. Using lipopolysaccharide (LPS)-stimulated human whole blood as an ex vivo model of sepsis, the kinetics of messenger RNA (mRNA) up-regulation and protein release of these cytokines were examined. Two waves of cytokine gene activation were documented. TNF and IL-6 were induced in the first wave with mRNA levels peaking between 2-4 hours and then rapidly declining. TNF and IL-6 protein peaked at 4-6 hours and then stabilized. IL-8 mRNA and protein were induced in the first wave, reached a plateau between 6-12 hours, and rose again in a second wave which continued to escalate until the end of the 24 hour study. These data demonstrate the complex patterns of cytokine gene expression and suggest that production of early mediators may augment continued expression of IL-8 to recruit and retain neutrophils at a site of inflammation.


Assuntos
Interleucina-6/genética , Interleucina-8/genética , Leucócitos/metabolismo , Lipopolissacarídeos/farmacologia , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética , Sequência de Bases , Regulação da Expressão Gênica , Humanos , Interleucina-6/biossíntese , Interleucina-8/biossíntese , Cinética , Masculino , Dados de Sequência Molecular , Ativação Transcricional , Fator de Necrose Tumoral alfa/biossíntese
14.
Am J Pathol ; 140(5): 1045-54, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1533750

RESUMO

Interleukin-8 (IL-8) is a neutrophil and lymphocyte chemoattractant and activator that may play an important role in mediating events at sites of inflammation. IL-8 is produced by many cell types in response to a variety of inducers, including interleukin-1 (IL-1). Studies were conducted to address the question of whether an inhibitor of IL-1 action, IL-1 receptor antagonist protein (IRAP), would suppress IL-8 production. Lipopolysaccharide (LPS)-stimulated human whole blood was used as an ex vivo model of local cytokine production. Preliminary time course studies showed that plasma IL-1 beta levels were fully induced by 6 hours (approximately 15 ng/ml) and persisted at this level over 24 hours. IL-8 production, in contrast, reached a plateau between 6 to 12 hours (5 ng/ml) and then increased rapidly to 17 ng/ml at 24 hours. Addition of IRAP was found to dose-dependently inhibit IL-8 expression at the levels of both protein and mRNA. A 50% reduction in IL-8 protein release occurred at an IRAP dose of 8 micrograms/ml (5 x 10(-7) mol/l) at 24 hours. A 2 hour delay in the addition of IRAP relative to LPS still permitted optimal reduction in IL-8 release, whereas delays of 4-8 hours reduced or eliminated the inhibitory effect. IRAP was found to have no effect on the LPS-stimulated production of IL-1 alpha or IL-1 beta. In addition, experiments performed with isolated peripheral blood cells demonstrated that, whereas monocytes were the major producers of IL-8, IRAP was equally effective in reducing IL-8 production in neutrophil and mononuclear cell suspensions. These studies further document the role of IL-1 in inducing the production of IL-8 and indicate that the ability of IRAP to suppress IL-8 expression may be an important mechanism of the anti-inflammatory properties of this molecule.


Assuntos
Interleucina-8/antagonistas & inibidores , Lipopolissacarídeos , Proteínas/farmacologia , Sialoglicoproteínas , Sequência de Bases , Células Sanguíneas/metabolismo , Separação Celular , Sobrevivência Celular , Relação Dose-Resposta a Droga , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/sangue , Interleucina-8/sangue , Interleucina-8/genética , Dados de Sequência Molecular , Sondas de Oligonucleotídeos/genética , RNA Mensageiro/metabolismo
15.
Am J Pathol ; 144(3): 599-611, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8129045

RESUMO

Previous reports have indicated that immunological priming of animals will result in increased cytokine production and enhanced susceptibility to the toxicity of cytokines. We primed mice with complete Freund's adjuvant and challenged 2 weeks later with 1 mg/mouse of lipopolysaccharide. Primed mice produced less tumor necrosis factor than naive mice (35 +/- 8 vs 108 +/- 20 ng/ml) and also less interleukin-6 (182 +/- 37 vs 6.39 +/- 155 ng/ml). Leukopenia developed only in the naive mice. Although neutropenia and lymphocytosis developed in both groups, the alterations manifested themselves more quickly in primed mice. Primed mice had substantially greater pulmonary neutrophil sequestration determined both enzymatically and histologically but no lung damage. However, primed mice had significantly less small bowel damage than naive mice. Mortality was substantially reduced in primed mice compared with unprimed mice. These results demonstrate that immunological priming in vivo decreases cytokine production in response to lipopolysaccharide challenge, decreases organ injury, and reduces mortality.


Assuntos
Citocinas/efeitos adversos , Citocinas/metabolismo , Adjuvante de Freund/farmacologia , Lipopolissacarídeos/farmacologia , Animais , Contagem de Células Sanguíneas , Movimento Celular/fisiologia , Citocinas/análise , Feminino , Interleucina-6/sangue , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/patologia , Intestino Delgado/fisiologia , Leucopenia/patologia , Pulmão/patologia , Pulmão/fisiologia , Camundongos , Camundongos Endogâmicos CBA , Modelos Biológicos , Neutropenia/patologia , Neutrófilos/patologia , Neutrófilos/fisiologia , Fatores de Tempo , Fator de Necrose Tumoral alfa/análise
16.
Immunol Invest ; 21(4): 321-7, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1398781

RESUMO

The synovial fluid aspirated from patients with symptomatic arthritis was analyzed for the presence of tumor necrosis factor (TNF), interleukin 6 (IL-6) and interleukin 8 (IL-8). All three cytokines were found in both inflammatory and non-inflammatory arthritides: IL-8 levels ranged from less than 20 to 38,990 pg/ml, IL-6 from less than 10 to 72,300 pg/ml and TNF from less than 4 to 61 pg/ml. No inhibitors of cytokine activity were found. IL-8 and IL-6 were present in significantly higher levels in patients with inflammatory arthritis compared to patients with osteoarthritis, and there was significant correlation between the IL-6 and IL-8 levels. These findings document the presence of multiple cytokines in the synovial fluid specimens of patients with arthritis, and demonstrate that higher cytokine levels accompany inflammatory arthritis.


Assuntos
Artrite/metabolismo , Interleucina-6/análise , Líquido Sinovial/química , Fator de Necrose Tumoral alfa/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite/patologia , Artrite Reumatoide/metabolismo , Humanos , Inflamação , Pessoa de Meia-Idade , Osteoartrite/metabolismo
17.
Br J Haematol ; 86(1): 36-40, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8011545

RESUMO

Serum levels of interleukin 8 (IL-8) were examined in eight patients with acute myeloid leukaemia during 16 courses of chemotherapy. The patients experienced 14 episodes of fever which occurred in periods with granulocyte counts < 0.5 x 10(9)/l. Febrile episodes were classified as bacteriologically defined infection (n = 6), clinically defined infection (n = 2), and unexplained fever (n = 6). IL-8 was detected in 18/25 (72%), 2/3 (67%) and 3/7 (43%) of the serum samples in the respective groups. In contrast, IL-8 was detected in 22/90 (24%) of the samples taken when no fever was present (P < 0.00003 versus bacteriologically defined infection). The median concentration of IL-8 in samples taken during febrile episodes was 194 ng/ml (range 0-6358 ng/ml) and 0 (range 0-5392 ng/ml) on days without fever (not significant). In three patients with infections caused by, respectively, Streptococcus sanguis, Acinetobacter calcoanitratus and Candida albicans, IL-8 rose to a peak levels and declined during recovery. We conclude that IL-I is released systemically during infections with gram-positive and gram-negative bacteria and Candida albicans in patients with acute myeloid leukaemia and peripheral granulocytopenia due to chemotherapy. However, IL-8 can also be detected when no sign of infection is present.


Assuntos
Agranulocitose/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Interleucina-8/sangue , Leucemia Mieloide/imunologia , Infecções Oportunistas/imunologia , Doença Aguda , Adulto , Agranulocitose/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Febre/imunologia , Humanos , Leucemia Mieloide/tratamento farmacológico , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade
18.
Am J Pathol ; 143(4): 1121-30, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8214006

RESUMO

To investigate the differences in cytokine regulation in vitro as compared to in vivo, we examined the synthesis of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) by peritoneal macrophages in response to lipopolysaccharide (LPS). Mice (CBA/J) were primed with an intraperitoneal injection of complete Freund's adjuvant and after 2 weeks, peritoneal cells were harvested for culture or mice were injected intraperitoneally with LPS for in vivo studies. In ascites fluid, TNF-alpha peaked 1 hour after LPS and returned to baseline levels by 4 hours. In contrast, TNF-alpha in the media reached maximum at 7 hours. Expression of TNF-alpha messenger (m)RNA in vivo was rapid but transient, as levels peaked at 15 minutes and returned to baseline 1 hour after LPS. In contrast, TNF-alpha mRNA in vitro became maximal at 1 hour, but remained elevated to 5 hours after LPS. In vivo, IL-6 in ascites fluid peaked at 2 hours, whereas in vitro, IL-6 continued increasing to 24 hours. In vivo, IL-6 mRNA reached maximum at 30 minutes, but fell below baseline by 1.5 hours after LPS. In contrast, IL-6 mRNA in vitro was sustained at maximal expression between 5 to 9 hours after LPS. These results demonstrate that both TNF-alpha and IL-6 synthesis is more rapid in vivo than in vitro. The rapid kinetics of cytokine expression in vivo must considered when designing strategies to inhibit cytokine action in vivo.


Assuntos
Interleucina-6/metabolismo , Macrófagos Peritoneais/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Sequência de Bases , Northern Blotting , Células Cultivadas , Feminino , Interleucina-6/genética , Camundongos , Camundongos Endogâmicos CBA , Dados de Sequência Molecular , Sondas de Oligonucleotídeos/genética , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética
19.
Pharm Res ; 6(12): 1011-6, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2622856

RESUMO

In an effort to visualize whole body cholesteryl ester (CE) deposition using the nuclear medicine imaging technique of gamma camera scintigraphy, 125I-cholesteryl iopanoate (125I-CI), a nonhydrolyzable CE analogue, was used as a marker for CE deposition in atherosclerotic New Zealand white rabbits. Groups of animals were fed either a cholesterol-enriched diet (2%, w/w) or the same diet supplemented with the hypolipidemic drugs colestipol (1%, w/w) and/or clofibrate (0.3%, w/w). Injections of 125I-CI were administered biweekly. At the end of 15 weeks, animals were scintigraphically scanned and sacrificed for tissue analysis. The results demonstrated that while drug treatment had no significant effect on plasma lipid levels, it substantially lessened atherosclerotic involvement in the thoracic-abdominal aorta. These differences in aortic lipid accumulation were reflected in the whole-body scans which showed a reduction in tissue accumulation of 125I-CI in the drug-treated groups. Gamma camera scintigraphy thus represents a rapid means of visualizing tissue CE accumulation which could facilitate the evaluation of lipid-lowering drug efficacy and possible antiatherosclerotic effect.


Assuntos
Arteriosclerose/tratamento farmacológico , Ésteres do Colesterol/metabolismo , Clofibrato/uso terapêutico , Colestipol/uso terapêutico , Poliaminas/uso terapêutico , Animais , Arteriosclerose/etiologia , Arteriosclerose/metabolismo , Colesterol na Dieta , Feminino , Radioisótopos do Iodo , Coelhos , Cintilografia
20.
J Immunol ; 148(7): 2133-41, 1992 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-1545121

RESUMO

TNF, IL-1, and IL-6 are integral components of the cytokine cascade released in the response to inflammatory stimuli such as LPS. IL-8 is produced both in response to LPS as well as TNF and IL-1. The early, local production of TNF and IL-1 may therefore contribute to the subsequent expression of IL-8. This hypothesis was tested using LPS-stimulated human whole blood as an ex vivo model of local cytokine production. The production of TNF, IL-1 alpha, IL-1 beta, IL-6, and IL-8 was found to be responsive to a wide range of LPS concentrations (0.1 ng/ml-10 micrograms/ml). These cytokines were first detected between 1 to 4 h post-LPS stimulation, and reached plateau levels after 6 to 12 h. IL-8, however, also displayed a secondary wave of production, with the levels again increasing between 12 to 24 h. The IL-8 present in the plasma after LPS stimulation was biologically active, as assessed by neutrophil chemotaxis. In further studies, addition of anti-TNF and anti-IL-1 neutralizing antibodies, alone and in combination, to LPS-stimulated blood resulted in nearly complete ablation of the secondary phase of IL-8 synthesis at both the levels of protein and mRNA, while leaving the first, LPS-mediated phase of IL-8 synthesis unaffected. This model of cytokine production in human whole blood may reflect the sequence of events in a localized environment of inflammation where both a primary stimulus and the induced early cytokine mediators may serve to elicit multiple, temporally distinct phases of IL-8 production.


Assuntos
Anticorpos Monoclonais/imunologia , Interleucina-1/fisiologia , Interleucina-8/biossíntese , Lipopolissacarídeos , Fator de Necrose Tumoral alfa/fisiologia , Sequência de Bases , Citocinas/biossíntese , Ensaio de Imunoadsorção Enzimática , Humanos , Interleucina-1/imunologia , Interleucina-8/genética , Masculino , Dados de Sequência Molecular , RNA Mensageiro/análise , Fator de Necrose Tumoral alfa/imunologia
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