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1.
Cancer ; 121(18): 3335-42, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26079197

RESUMO

BACKGROUND: The main objectives of this study were to identify the number of randomized controlled trials (RCTs) including a patient-reported outcome (PRO) endpoint across a wide range of cancer specialties and to evaluate the completeness of PRO reporting according to the Consolidated Standards of Reporting Trials (CONSORT) PRO extension. METHODS: RCTs with a PRO endpoint that had been performed across several cancer specialties and published between 2004 and 2013 were considered. Studies were evaluated on the basis of previously defined criteria, including the CONSORT PRO extension and the Cochrane Collaboration's tool for assessing the risk of bias of RCTs. Analyses were also conducted by the type of PRO endpoint (primary vs secondary) and by the cancer disease site. RESULTS: A total of 56,696 potentially eligible records were scrutinized, and 557 RCTs with a PRO evaluation, enrolling 254,677 patients overall, were identified. PROs were most frequently used in RCTs of breast (n = 123), lung (n = 85), and colorectal cancer (n = 66). Overall, PROs were secondary endpoints in 421 RCTs (76%). Four of 6 evaluated CONSORT PRO items were documented in less than 50% of the RCTs. The level of reporting was higher in RCTs with a PRO as a primary endpoint. The presence of a supplementary report was the only statistically significant factor associated with greater completeness of reporting for both RCTs with PROs as primary endpoints (ß = .19, P = .001) and RCTs with PROs as secondary endpoints (ß = .30, P < .001). CONCLUSIONS: Implementation of the CONSORT PRO extension is equally important across all cancer specialties. Its use can also contribute to revealing the robust PRO design of some studies, which might be obscured by poor outcome reporting.


Assuntos
Neoplasias/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Projetos de Pesquisa/normas , Autorrelato/normas , Humanos , Avaliação de Resultados da Assistência ao Paciente
2.
Blood ; 120(3): 511-8, 2012 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22661701

RESUMO

Extracellular ATP (eATP), the most abundant among nucleotides, can act as a mediator during inflammatory responses by binding to plasmamembrane P2 purinergic receptors, which are widely expressed on cells of the immune system. eATP is generally considered as a classical danger signal, which stimulates immune responses in the presence of tissue damage. Converging evidence from several studies using murine models of chronic inflammation have supported this hypothesis; however, the role of eATP in the regulation of human immune function appears to be more complex. Chronic stimulation with micromolar eATP concentrations inhibits the proliferation of T and NK lymphocytes and enhances the capacity of dendritic cells to promote tolerance. The effect of eATP depends on multiple factors, such as the extent of stimulation, eATP concentration, presence/absence of other mediators in the microenvironment, and pattern of P2 receptor engagement. Small but significant differences in the pattern of P2 receptor expression in mice and humans confer the diverse capacities of ATP in regulating the immune response. Such diversity, which is often overlooked, should therefore be carefully considered when evaluating the role of eATP in human inflammatory and autoimmune diseases.


Assuntos
Trifosfato de Adenosina/imunologia , Espaço Extracelular/imunologia , Sistema Imunitário/imunologia , Inflamação/imunologia , Animais , Membrana Celular/imunologia , Doença Crônica , Humanos , Células Matadoras Naturais/imunologia , Camundongos , Neutrófilos/imunologia , Receptores Purinérgicos P2X/imunologia , Receptores Purinérgicos P2Y/imunologia , Linfócitos T/imunologia
3.
J Exp Med ; 203(10): 2339-50, 2006 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-17000867

RESUMO

In this study, we demonstrate that the in vitro interactions between a CD56(neg)/CD16(pos) (CD56(neg)) subset of natural killer (NK) cells and autologous dendritic cells (DCs) from HIV-1-infected viremic but not aviremic individuals are markedly impaired and likely interfere with the development of an effective immune response. Among the defective interactions are abnormalities in the process of reciprocal NK-DC activation and maturation as well as a defect in the NK cell-mediated editing or elimination of immature DCs (iDCs). Notably, the lysis of mature DCs (mDCs) by autologous NK cells was highly impaired even after the complete masking of major histocompatibility complex I molecules, suggesting that the defective elimination of autologous iDCs is at the level of activating NK cell receptors. In this regard, the markedly impaired expression/secretion and function of NKp30 and TNF-related apoptosis-inducing ligand, particularly among the CD56(neg) NK cell subset, largely accounts for the highly defective NK cell-mediated lysis of autologous iDCs. Moreover, mDCs generated from HIV-1 viremic but not aviremic patients are substantially impaired in their ability to secrete interleukin (IL)-10 and -12 and to prime the proliferation of neighboring autologous NK cells, which, in turn, fail to secrete adequate amounts of interferon-gamma.


Assuntos
Células Dendríticas/imunologia , Infecções por HIV/imunologia , HIV-1 , Células Matadoras Naturais/imunologia , Adulto , Anticorpos Monoclonais , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Citometria de Fluxo , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Ativação Linfocitária/imunologia , Microscopia de Fluorescência , Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
4.
Blood ; 116(22): 4492-500, 2010 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-20668227

RESUMO

Endothelial cells (ECs) represent a major source of actively secreted adenosine triphosphate (ATP). Natural killer (NK) cells can mediate vascular injury in several pathologic conditions, including cytomegalovirus infection and vascular leak syndrome. We studied NK-cell expression of P2 receptors and the role of these nucleotide receptors in the regulation of endothelial-NK cell cross-talk. NK cells from healthy subjects expressed P2Y(1,2,4,6,11,12,13,14) and P2X(1,4,5,6,7) receptors. NK cells stimulated with ATP, but not uridine triphosphate, increased intracellular Ca²(+) and chemokinesis. Moreover, ATP, but not uridine triphosphate, inhibited NK chemotaxis in response to CX3CL1, whereas chemotaxis to CXCL12 was increased. CX3CL1 elicited killing of human umbilical vein ECs and human coronary artery ECs by NK cells. However, in the presence of ATP, CX3CL1 failed to stimulate killing of ECs. Such inhibitory effect was lost on exogenous addition of the ATP-hydrolyzing enzyme apyrase or by pharmacologic inhibition of the P2Y11R, and correlated with increased intracellular cyclic adenosine monophosphate concentrations induced by ATP or other P2Y11R agonists, including NAD(+). Extracellular ATP regulates NK-cell cytotoxicity via P2Y11R activation, protecting ECs from CX3CL1-elicited NK cell-mediated killing. These findings point out the P2Y11R as a potential target for pharmacologic intervention aimed at reducing NK-mediated vascular injury.


Assuntos
Trifosfato de Adenosina/imunologia , Quimiocina CX3CL1/imunologia , Quimiotaxia , Células Endoteliais/imunologia , Células Matadoras Naturais/imunologia , Receptores Purinérgicos P2/imunologia , Cálcio/imunologia , Linhagem Celular , AMP Cíclico/imunologia , Células Endoteliais/citologia , Expressão Gênica , Humanos , Células Matadoras Naturais/citologia , RNA Mensageiro/genética , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2X/genética , Receptores Purinérgicos P2X/imunologia , Receptores Purinérgicos P2Y/genética , Receptores Purinérgicos P2Y/imunologia
5.
Circ Res ; 102(11): 1359-67, 2008 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-18467630

RESUMO

In clinical trials, aldosterone antagonists decrease cardiovascular mortality and ischemia by unknown mechanisms. The steroid hormone aldosterone acts by binding to the mineralocorticoid receptor (MR), a ligand-activated transcription factor. In humans, aldosterone causes MR-dependent endothelial cell (EC) dysfunction and in animal models, aldosterone increases vascular macrophage infiltration and atherosclerosis. MR antagonists inhibit these effects without changing blood pressure, suggesting a direct role for vascular MR in EC function and atherosclerosis. Whether human vascular ECs express functional MR is not known. Here, we show that human coronary artery and aortic ECs express MR mRNA and protein and that EC MR mediates aldosterone-dependent gene transcription. Human ECs also express the enzyme 11-beta-hydroxysteroid dehydrogenase-2 (11betaHSD2), and inhibition of 11betaHSD2 in aortic ECs enhances gene transactivation by cortisol, supporting that EC 11betaHSD2 is functional. Furthermore, aldosterone stimulates transcription of the proatherogenic leukocyte-EC adhesion molecule intercellular adhesion molecule (ICAM)1 gene and protein expression on human coronary artery ECs, an effect inhibited by the MR antagonist spironolactone and by MR knock down with small interfering RNA. Cell adhesion assays demonstrate that aldosterone promotes leukocyte-EC adhesion, an effect that is inhibited by spironolactone and ICAM1 blocking antibody, supporting that aldosterone induction of EC ICAM1 surface expression via MR mediates leukocyte-EC adhesion. These data show that aldosterone activates endogenous EC MR and proatherogenic gene expression in clinically important human ECs. These studies describe a novel mechanism by which aldosterone may influence ischemic cardiovascular events and support a new explanation for the decrease in ischemic events in patients treated with aldosterone antagonists.


Assuntos
Células Endoteliais/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Leucócitos/fisiologia , Receptores de Mineralocorticoides/metabolismo , Aldosterona/farmacologia , Aldosterona/fisiologia , Aorta/citologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Linhagem Celular , Vasos Coronários/citologia , Células Endoteliais/efeitos dos fármacos , Humanos , Molécula 1 de Adesão Intercelular/genética , Leucócitos/citologia , Antagonistas de Receptores de Mineralocorticoides/farmacologia , RNA Mensageiro/biossíntese , RNA Interferente Pequeno/farmacologia , Receptores de Mineralocorticoides/efeitos dos fármacos , Receptores de Mineralocorticoides/genética , Espironolactona/farmacologia , Transcrição Gênica/efeitos dos fármacos
6.
Front Immunol ; 11: 617804, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33664731

RESUMO

Atherosclerosis is a hardening and narrowing of arteries causing a reduction of blood flow. It is a leading cause of death in industrialized countries as it causes heart attacks, strokes, and peripheral vascular disease. Pathogenesis of the atherosclerotic lesion (atheroma) relies on the accumulation of cholesterol-containing low-density lipoproteins (LDL) and on changes of artery endothelium that becomes adhesive for monocytes and lymphocytes. Immunomediated inflammatory response stimulated by lipoprotein oxidation, cytokine secretion and release of pro-inflammatory mediators, worsens the pathological context by amplifying tissue damage to the arterial lining and increasing flow-limiting stenosis. Formation of thrombi upon rupture of the endothelium and the fibrous cup may also occur, triggering thrombosis often threatening the patient's life. Purinergic signaling, i.e., cell responses induced by stimulation of P2 and P1 membrane receptors for the extracellular nucleotides (ATP, ADP, UTP, and UDP) and nucleosides (adenosine), has been implicated in modulating the immunological response in atherosclerotic cardiovascular disease. In this review we will describe advancements in the understanding of purinergic modulation of the two main immune cells involved in atherogenesis, i.e., monocytes/macrophages and T lymphocytes, highlighting modulation of pro- and anti-atherosclerotic mediated responses of purinergic signaling in these cells and providing new insights to point out their potential clinical significance.


Assuntos
Aterosclerose/imunologia , Macrófagos/imunologia , Receptores Purinérgicos P1/metabolismo , Receptores Purinérgicos P2/metabolismo , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Animais , Aterosclerose/metabolismo , Humanos , Macrófagos/metabolismo , Receptores Purinérgicos P1/imunologia , Receptores Purinérgicos P2/imunologia , Linfócitos T/metabolismo
7.
Circulation ; 113(1): 118-24, 2006 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-16380545

RESUMO

BACKGROUND: Previous studies have demonstrated that macrophages and CD4+ T lymphocytes play pivotal roles in collateral development. Indirect evidence suggests that CD8+ T cells also play a role. Thus, after acute cerebral ischemia, CD8+ T cells infiltrate the perivascular space and secrete interleukin-16 (IL-16), a potent chemoattractant for monocytes and CD4+ T cells. We tested whether CD8+ T lymphocytes contribute to collateral vessel development and whether the lack of circulating CD8+ T cells prevents IL-16 expression, impairs CD4+ mononuclear cell recruitment, and reduces collateral vessel growth after femoral artery ligation in CD8(-/-) mice. METHODS AND RESULTS: After surgical excision of the femoral artery, laser Doppler perfusion imaging demonstrated reduced blood flow recovery in CD8(-/-) mice compared with C57/BL6 mice (ischemic/nonischemic limb at day 28, 0.66+/-0.04 versus 0.87+/-0.04, respectively; P<0.01). This resulted in greater calf muscle atrophy (mean fiber area, 785+/-68 versus 1067+/-69 microm2, respectively; P<0.01) and increased fibrotic tissue content (10.8+/-1.2% versus 7+/-1%, respectively; P<0.01). Moreover, CD8(-/-) mice displayed reduced IL-16 expression and decreased CD4+ T-cell recruitment at the site of collateral vessel development. Exogenous CD8+ T cells, infused into CD8(-/-) mice immediately after femoral artery ligation, selectively homed to the ischemic hind limb and expressed IL-16. The restoration of IL-16 expression resulted in significant CD4+ mononuclear cell infiltration of the ischemic limb, faster blood flow recovery, and reduced hindlimb muscle atrophy/fibrosis. When exogenous CD8+ T cells deficient in IL-16 (IL-16(-/-)) were infused into CD8(-/-) mice immediately after femoral artery ligation, they selectively homed to the ischemic hind limb but were unable to recruit CD4+ mononuclear cells and did not improve blood flow recovery. CONCLUSIONS: These results demonstrate that CD8+ T cells importantly contribute to the early phase of collateral development. After femoral artery ligation, CD8+ T cells infiltrate the site of collateral vessel growth and recruit CD4+ mononuclear cells through the expression of IL-16. Our study provides further evidence of the significant role of the immune system in modulating collateral development in response to peripheral ischemia.


Assuntos
Arteriolosclerose/etiologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/fisiologia , Quimiotaxia de Leucócito/fisiologia , Circulação Colateral/imunologia , Interleucina-16/fisiologia , Isquemia/complicações , Animais , Arteriolosclerose/imunologia , Antígenos CD8/genética , Modelos Animais de Doenças , Artéria Femoral , Sistema Imunitário/fisiologia , Interleucina-16/biossíntese , Camundongos , Camundongos Knockout
8.
J Leukoc Biol ; 79(1): 7-15, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16244111

RESUMO

A growing body of information indicates that release of intracellular nucleotides represents an important way to modulate several cell pathways in physiological or pathological conditions. Nucleotides released as a consequence of cell damage, cell stress, bacterial infection, or other noxious stimuli signal at a class of plasma membrane receptors--P2 receptors--activating diverse intracellular pathways in many tissues and organs. For example, nucleotides secreted in the airway system control chloride/liquid secretion, goblet cell degranulation, and ciliary beat frequency. Several studies indicate that nucleotides play a role in airway diseases through their action on multiple cell types, including mast cells, dendritic cells, neurons, and eosinophils. Recent work by us and other groups led to the identification and characterization of P2 receptors expressed by human eosinophils. In this review, we will summarize recent developments in this field and put forward a hypothesis about the role of P2 receptors in pathophysiological conditions where eosinophils are major players.


Assuntos
Degranulação Celular/imunologia , Eosinófilos/imunologia , Células Caliciformes/fisiologia , Nucleotídeos/imunologia , Receptores Purinérgicos P2/imunologia , Transdução de Sinais/imunologia , Animais , Infecções Bacterianas/imunologia , Infecções Bacterianas/patologia , Cílios/imunologia , Células Dendríticas/imunologia , Células Dendríticas/patologia , Eosinófilos/patologia , Regulação da Expressão Gênica/imunologia , Humanos , Transporte de Íons/imunologia , Mastócitos/imunologia , Mastócitos/patologia , Neurônios/imunologia , Neurônios/patologia , Doenças Respiratórias/imunologia , Doenças Respiratórias/patologia
10.
Circulation ; 108(2): 205-10, 2003 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12821542

RESUMO

BACKGROUND: T lymphocytes, components of the immune and inflammatory systems, are involved in such normal processes as wound healing and host defense against infection and in such pathological processes as tumor growth and atherosclerotic plaque development. Angiogenesis is a mechanism common to each. Because CD4+ T lymphocytes are active in regulating humoral and cellular responses of the immune system, we determined whether CD4+ cells contribute to collateral vessel development by using the mouse ischemic hindlimb model. METHODS AND RESULTS: One week after ischemia, CD4-/- mice showed reduced collateral flow induction, macrophage number, and vascular endothelial growth factor levels in the ischemic muscle compared with wild-type mice. There was also delayed recovery of hindlimb function and increased muscle atrophy/fibrosis. Spleen-derived purified CD4+ T cells infused into CD4-/- mice selectively localized to the ischemic limb and significantly increased collateral flow as well as macrophage number and vascular endothelial growth factor levels in the ischemic muscle. Muscle function and damage also improved. CONCLUSIONS: These results indicate an important role of CD4+ cells in collateral development, as demonstrated by a 25% decrease in blood flow recovery after femoral artery ligation. Our data also suggest that CD4+ T cells control the arteriogenic response to acute hindlimb ischemia, at least in part, by recruiting macrophages to the site of active collateral artery formation, which in turn triggers the development of collaterals through the synthesis of arteriogenic cytokines.


Assuntos
Artérias/fisiopatologia , Antígenos CD4/genética , Membro Posterior/irrigação sanguínea , Isquemia/fisiopatologia , Neovascularização Fisiológica , Doença Aguda , Animais , Artérias/patologia , Antígenos CD4/metabolismo , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD4-Positivos/transplante , Células Cultivadas , Circulação Colateral/imunologia , Modelos Animais de Doenças , Progressão da Doença , Artéria Femoral/fisiopatologia , Citometria de Fluxo , Membro Posterior/patologia , Membro Posterior/fisiopatologia , Inflamação/patologia , Isquemia/patologia , Isquemia/terapia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/imunologia , Recuperação de Função Fisiológica , Fluxo Sanguíneo Regional
11.
J Leukoc Biol ; 73(3): 339-43, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12629147

RESUMO

The interplay between pro- and anti-inflammatory mechanisms during inflammatory and immune responses is critical for avoiding excessive tissue damage. Extracellular nucleotides (e.g., adenosine 5'-triphosphate) may represent constitutive signals that can alert the immune system of abnormal cell death. Relatively high doses of nucleotides induce rapid release of proinflammatory mediators and favor pathogen killing. However, recent findings on antigen presenting cells, particularly dendritic cells, revealed a more complex role for these molecules. Chronic exposure to low-dose nucleotides can redirect cellular responses to prototypic activation stimuli, leading to suppressed inflammation and immune deviation.


Assuntos
Sistema Imunitário/fisiologia , Nucleotídeos/fisiologia , Animais , Células Dendríticas/efeitos dos fármacos , Humanos , Sistema Imunitário/citologia , Sistema Imunitário/efeitos dos fármacos , Imunidade Celular/efeitos dos fármacos , Nucleotídeos/farmacologia , Receptores Purinérgicos P2/imunologia , Receptores Purinérgicos P2/metabolismo
12.
Trends Mol Med ; 21(3): 184-92, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25637413

RESUMO

Cell surface expression of specific receptors and ecto-nucleotidases makes extracellular nucleotides such as ATP, ADP, UTP, and adenosine suitable as signaling molecules for physiological and pathological events, including tissue stress and damage. Recent data have revealed the participation of purinergic signaling in atherosclerosis, depicting a scenario in which, in addition to some exceptions reflecting dual effects of individual receptor subtypes, adenosine and most P1 receptors, as well as ecto-nucleotidases, show a protective, anti-atherosclerotic function. By contrast, P2 receptors promote atherosclerosis. In consideration of these findings, modulation of purinergic signaling would represent an innovative and valuable tool to counteract atherosclerosis. We summarize recent developments on the participation of the purinergic network in atheroma formation and evolution.


Assuntos
Aterosclerose/metabolismo , Receptores Purinérgicos/metabolismo , Transdução de Sinais , Animais , Ensaios Clínicos como Assunto , Progressão da Doença , Humanos , Modelos Biológicos
13.
Virology ; 485: 189-98, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26280469

RESUMO

Given the pivotal role of monocyte-derived dendritic cells (DCs) in determining the magnitude of the antiviral innate immune response, we sought to determine whether Usutu virus (USUV) and West Nile virus (WNV) lineages (L)1 and L2 can infect DCs and affect the rate of type I interferon (IFN) activation. The sensitivity of these viruses to types I and III IFNs was also compared. We found that USUV can infect DCs, induce higher antiviral activities, IFN alpha subtypes and the IFN stimulated gene (ISG)15 pathway, and is more sensitive to types I and III IFNs than WNVs. In contrast, we confirmed that IFN alpha/beta subtypes were more effective against WNV L2 than WNV L1. However, the replication kinetics, induction of IFN alpha subtypes and ISGs in DCs and the sensitivity to IFN lambda 1-3 did not differ between WNV L1 and L2.


Assuntos
Células Dendríticas/efeitos dos fármacos , Vírus da Encefalite Japonesa (Subgrupo)/efeitos dos fármacos , Interferon-alfa/farmacologia , Interferon beta/farmacologia , Vírus do Nilo Ocidental/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal , Diferenciação Celular , Citocinas/genética , Citocinas/imunologia , Células Dendríticas/imunologia , Células Dendríticas/virologia , Vírus da Encefalite Japonesa (Subgrupo)/genética , Vírus da Encefalite Japonesa (Subgrupo)/imunologia , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Interferon-alfa/classificação , Interferon-alfa/genética , Interferon-alfa/imunologia , Interferon beta/classificação , Interferon beta/genética , Interferon beta/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Lipopolissacarídeos/farmacologia , Monócitos/citologia , Cultura Primária de Células , Proteínas de Ligação a RNA , Transdução de Sinais , Especificidade da Espécie , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia , Ubiquitinas/genética , Ubiquitinas/imunologia , Carga Viral/efeitos dos fármacos , Carga Viral/imunologia , Replicação Viral/efeitos dos fármacos , Replicação Viral/imunologia , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/imunologia
14.
Am J Blood Res ; 3(1): 14-28, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23358447

RESUMO

Extracellular ATP (eATP) is the most abundant among extracellular nucleotides and is commonly considered as a classical danger signal, which stimulates immune responses in the presence of tissue injury. In fact, increased nucleotide concentration in the extracellular space is generally closely associated with tissue stress or damage. However non-lytic nucleotide release may also occur in many cell types under a variety of conditions. Extracellular nucleotides are sensed by a class of plasma membrane receptors called P2 purinergic receptors (P2Rs). P2 receptors are expressed by all immunological cells and their activation elicits different responses. Extracellular ATP can act as an initiator or terminator of immune responses being able to induce different effects on immune cells depending on the pattern of P2 receptors engaged, the duration of the stimulus and its concentration in the extracellular milieu. Millimolar (high) concentrations of extracellular ATP, induce predominantly proinflammatory effects, while micromolar (low) doses exert mainly tolerogenic/immunosuppressive action. Moreover small, but significant differences in the pattern of P2 receptor expression in mice and humans confer diverse capacities of ATP in regulating the immune response.

15.
Trends Mol Med ; 18(8): 494-501, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22818027

RESUMO

The development of collateral circulation is an inherent compensatory mechanism to restore impaired blood perfusion following artery stenosis and/or occlusion. This process, termed arteriogenesis, is driven by inflammation and involves a complex remodeling of pre-existing conduit vessels running in parallel to the occluded artery. Recent studies have unveiled roles for different immune cell subsets as regulators of arteriogenesis, including natural killer (NK) cells, T helper 17 (Th17) cells, regulatory T lymphocytes (Tregs), and functional subsets of macrophages (e.g., M2 macrophages). This review summarizes recent findings and discusses future research needed to better define the time during which each cellular subset is active and reveal further critical regulatory switches.


Assuntos
Imunidade Adaptativa , Vasos Sanguíneos/crescimento & desenvolvimento , Vasos Sanguíneos/imunologia , Circulação Colateral , Imunidade Inata , Neovascularização Patológica/imunologia , Animais , Humanos , Linfócitos/imunologia , Neovascularização Patológica/fisiopatologia
16.
Eur J Heart Fail ; 13(6): 642-50, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21613428

RESUMO

AIMS: Physical training improves endothelial function and exercise capacity in patients with heart failure (HF). Serum from patients with cardiovascular diseases increases apoptosis of human endothelial cells suggesting the importance of humoral factors in the progression of the disease. We evaluated whether exercise training influences the apoptotic capacity of serum from patients with chronic HF (CHF). METHODS AND RESULTS: The study included 39 patients with HF (NYHA II) and 10 age-matched healthy controls. Patients were allocated to either a structured programme of exercise training (24 patients) or standard care (15 patients). Human umbilical vein endothelial cells (HUVECs) were incubated with a medium containing 20% serum obtained before and after either a 3-week exercise training programme or standard care. At baseline, serum from patients with CHF induced a higher degree of lactate dehydrogenase (LDH) release and apoptosis in HUVECs compared with healthy controls (43 ± 1.5 vs. 16 ± 1.1%, P< 0.001 and 67 ± 5.4 vs. 23 ± 5.8%, P< 0.001, respectively). Exercise training significantly increased performance in the 6 min walking test (+34.7%) and reduced the ability of serum to induce LDH release and apoptosis of HUVECs. The reduction of apoptosis after exercise training correlated with the improvement in functional capacity. The expression of the apoptosis markers Bax and Caspase-3 was significantly reduced in HUVECs exposed to serum collected after exercise training. Circulating tumour necrosis factor-alpha, matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels were significantly reduced by exercise training and the MMP-9/TIMP-1 ratio increased. CONCLUSION: A short term in-hospital structured cardiovascular training programme reduces the ability of serum-derived factors to induce endothelial cell death in patients with CHF.


Assuntos
Apoptose/fisiologia , Endotélio Vascular/fisiologia , Terapia por Exercício , Insuficiência Cardíaca/sangue , Soro/fisiologia , Idoso , Western Blotting , Estudos de Casos e Controles , Caspase 3/metabolismo , Doença Crônica , Estudos de Coortes , Endotélio Vascular/enzimologia , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Insuficiência Cardíaca/reabilitação , Humanos , L-Lactato Desidrogenase/metabolismo , Masculino , Metaloproteinases da Matriz/metabolismo , Pessoa de Meia-Idade , Veias Umbilicais/citologia , Proteína X Associada a bcl-2/metabolismo
17.
PLoS One ; 5(6): e11052, 2010 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-20548796

RESUMO

BACKGROUND: HIV-1 Protease Inhibitors, namely PIs, originally designed to inhibit HIV-1 aspartic protease, can modulate the immune response by mechanisms largely unknown, and independent from their activity on viral replication. Here, we analyzed the ability of PIs to interfere with differentiation program of monocytes toward dendritic cell (DCs) lineage, a key process in the inflammatory response. METHODOLOGY/PRINCIPAL FINDINGS: Monocytes from healthy donors were isolated and induced to differentiate in vitro in the presence or absence of saquinavir, ritonavir, nelfinavir, indinavir or amprenavir (sqv, rtv, nlfv, idv, apv, respectively). These drugs demonstrated a differential ability to sustain the generation of immature DCs (iDCs) with an altered phenotype, including low levels of CD1a, CD86, CD36 and CD209. DCs generated in the presence of rtv also failed to acquire the typical phenotype of mature DCs (mDCs), and secreted lower amounts of IL-12 and IL-15. Accordingly, these aberrant mDCs failed to support activation of autologous Natural Killer (NK) cells, and resulted highly susceptible to NK cell-mediated cytotoxicity. CONCLUSIONS/SIGNIFICANCE: Our findings uncover novel functional properties of PIs within the DC-NK cell cross-talk, unveiling the heterogeneous ability of members of this class drugs to drive the generation of atypical monocyte-derived DCs (MDDCs) showing an aberrant phenotype, a failure to respond appropriately to bacterial endotoxin, a weak ability to prime autologous NK cells, and a high susceptibility to NK cell killing. These unexpected properties might contribute to limit inflammation and viral spreading in HIV-1 infected patients under PIs treatment, and open novel therapeutical perspectives for this class drugs as immunomodulators in autoimmunity and cancer.


Assuntos
Células Dendríticas/efeitos dos fármacos , Inibidores da Protease de HIV/farmacologia , Protease de HIV/efeitos dos fármacos , Células Matadoras Naturais/efeitos dos fármacos , Proliferação de Células , Células Dendríticas/imunologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Imunofenotipagem , Células Matadoras Naturais/imunologia
18.
J Exp Med ; 206(6): 1227-35, 2009 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-19487420

RESUMO

Prior studies have demonstrated that cholera toxin (CT) and other cAMP-inducing factors inhibit interleukin (IL)-12 production from monocytes and dendritic cells (DCs). We show that CT inhibits Th1 responses in vivo in mice infected with Toxoplasma gondii. This correlated with low serum IL-12 levels and a selective reduction in the numbers of CD8alpha(+) conventional DCs (cDCs) in lymphoid organs. CT inhibited the function of interferon (IFN) regulatory factor (IRF) 8, a transcription factor known to positively regulate IL-12p35 and p40 gene expression, and the differentiation of CD8alpha(+) and plasmacytoid DCs (pDCs). Fluorescence recovery after photobleaching analysis showed that exposure to CT, forskolin, or dibutyryl (db) cAMP blocked LPS and IFN-gamma-induced IRF8 binding to chromatin. Moreover, CT and dbcAMP inhibited the binding of IRF8 to the IFN-stimulated response element (ISRE)-like element in the mouse IL-12p40 promoter, likely by blocking the formation of ISRE-binding IRF1-IRF8 heterocomplexes. Furthermore, CT inhibited the differentiation of pDCs from fms-like tyrosine kinase 3 ligand-treated bone marrow cells in vitro. Therefore, because IRF8 is essential for IL-12 production and the differentiation of CD8alpha(+) cDCs and pDCs, these data suggest that CT and other Gs-protein agonists can affect IL-12 production and DC differentiation via a common mechanism involving IRF8.


Assuntos
Antígenos CD8/imunologia , Diferenciação Celular/fisiologia , Toxina da Cólera/metabolismo , AMP Cíclico/metabolismo , Células Dendríticas/fisiologia , Fatores Reguladores de Interferon/imunologia , Interleucina-12/biossíntese , Animais , Linfócitos T CD8-Positivos , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/imunologia , Feminino , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Humanos , Fator Regulador 1 de Interferon/genética , Fator Regulador 1 de Interferon/imunologia , Fatores Reguladores de Interferon/genética , Interferon gama/imunologia , Interleucina-12/genética , Subunidade p40 da Interleucina-12/genética , Subunidade p40 da Interleucina-12/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Baço/citologia , Toxoplasmose/imunologia
19.
Purinergic Signal ; 3(1-2): 99-107, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18404423

RESUMO

Dendritic cells (DCs) activate and shape the adaptive immune response by capturing antigens, migrating to peripheral lymphoid organs where naïve T cells reside, expressing high levels of MHC and costimulatory molecules and secreting cytokines and chemokines. DCs are endowed with a high degree of functional plasticity and their functions are tightly regulated. Besides initiating adaptive immune responses, DCs play a key role in maintaining peripheral tolerance toward self-antigens. On the basis of the information gathered from the tissue where they reside, DCs adjust their functional activity to ensure that protective immunity is favoured while unwanted or exaggerated immune responses are prevented. A wide variety of signals from neighbouring cells affecting DC functional activity have been described. Here we will discuss the complex role of extracellular nucleotides in the regulation of DC function and the role of P2 receptors as possible tools to manipulate immune responses.

20.
J Immunol ; 177(10): 6974-82, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17082612

RESUMO

Prior studies indicated the ability of Abs to complement receptor 3 (CR3, CD11b/CD18) to suppress the production of IL-12 from immune cells. Therefore, we tested the ability of an anti-CR3 Ab (clone M1/70) to treat established IL-12-dependent Th1-mediated inflammation in murine models. Systemic administration of anti-CR3 significantly ameliorated established intestinal inflammation following the intrarectal administration of trinitrobenzene sulfonic acid (TNBS-colitis), as well as colitis and skin inflammation in C57BL/10 RAG-2(-/-) mice reconstituted with CD4+CD45RBhigh T cells. The hyperproliferative skin inflammation in this novel murine model demonstrated many characteristics of human psoriasis, and was prevented by the adoptive transfer of CD45RBlow T cells. In vitro and in vivo studies suggest that anti-CR3 treatment may act, at least in part, by directly inhibiting IL-12 production by APCs. Administration of anti-CR3 may be a useful therapeutic approach to consider for the treatment of inflammatory bowel disease and psoriasis in humans.


Assuntos
Anticorpos/uso terapêutico , Colite/terapia , Dermatite/terapia , Mediadores da Inflamação/uso terapêutico , Antígeno de Macrófago 1/imunologia , Psoríase/terapia , Transferência Adotiva , Animais , Anticorpos/administração & dosagem , Linfócitos T CD4-Positivos/transplante , Células Cultivadas , Colite/induzido quimicamente , Colite/imunologia , Dermatite/imunologia , Dermatite/patologia , Modelos Animais de Doenças , Feminino , Mediadores da Inflamação/administração & dosagem , Injeções Intravenosas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Nus , Psoríase/imunologia , Psoríase/patologia , Ácido Trinitrobenzenossulfônico/toxicidade
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