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1.
Wien Klin Wochenschr ; 129(7-8): 243-250, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28004266

RESUMEN

BACKGROUND: The recanalization success rate of chronic total occlusion (CTO) percutaneous coronary interventions (PCI) can be increased by the retrograde approach; however, the long-term outcome of patients undergoing retrograde procedures is unknown. AIM: We aimed to evaluate the long-term major adverse cardiac and cerebrovascular event (MACCE) rate (e.g. death, myocardial infarction, coronary artery bypass surgery and stroke) in patients after retrograde versus antegrade CTO-PCI. METHODS AND RESULTS: In a prospective single center study from January 2008 to June 2012, 396 consecutive patients with CTO (≥3 months old) were enrolled. The mean age was 63.4 ± 10.3 years and 86.4% were male. The success rate of the total patient cohort was 88.6%. The retrograde PCI, only attempted after a failed antegrade intervention, was performed in 18% (n = 71) of patients. Long-term MACCE rate (mean follow up 2.3 ± 1.6 years) was significantly higher in the unsuccessful compared to the successful CTO-PCI group (23.1% versus 9.4%, p = 0.01) and this was also the case in the subgroup of antegrade CTO-PCI. In the retrograde subgroup, however, procedural success had no impact on outcome. Patients with unsuccessful retrograde CTO-PCI had a significantly better collateral connection compared to patients with an unsuccessful antegrade approach. Independent predictors for MACCE were peripheral artery disease and an ejection fraction ≤30%. CONCLUSION: The long-term MACCE rate after unsuccessful recanalization was significantly higher, which was driven by a higher MACCE rate after unsuccessful versus successful antegrade approaches. In contrast, procedural success in the retrograde group had no impact on outcome.


Asunto(s)
Estenosis Coronaria/mortalidad , Estenosis Coronaria/cirugía , Muerte Súbita Cardíaca/epidemiología , Intervención Coronaria Percutánea/mortalidad , Intervención Coronaria Percutánea/métodos , Complicaciones Posoperatorias/mortalidad , Accidente Cerebrovascular/mortalidad , Comorbilidad , Femenino , Alemania/epidemiología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Prevalencia , Accidente Cerebrovascular/prevención & control , Tasa de Supervivencia , Resultado del Tratamiento
2.
Clin Res Cardiol ; 106(4): 249-258, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27752761

RESUMEN

AIMS: The use of the MitraClip system has gained widespread acceptance for the treatment of patients with mitral regurgitation (MR) who are not suitable for the conventional surgery. This study sought to investigate the early and 1-year outcome after MitraClip therapy of patients with MR and cardiac comorbidities. METHODS AND RESULTS: Outcomes through 12-month follow-up of patients (n = 528) who underwent MitraClip implantation were obtained from the German transcatheter mitral valve interventions (TRAMI) registry. The majority of these patients (n = 409, 77.5 %) also suffered from coronary artery disease (CAD). Patients with a dilated cardiomyopathy (DCM, n = 65, 12.3 %) or concomitant valvular aortic disease (AV, n = 54, 10.2 %) were less frequent. Although the prevalent pathogenesis was functional MR, patients with DCM had significantly more frequent a functional MR (96.9 %) compared to patients with CAD (74.9 %) or AV (62.5 %, p < 0.001). Technical success was achieved in 97.5 % of patients. Procedural echocardiograms demonstrated in the vast majority of patients a reduction from severe MR III to mild MR I with no difference between the groups (p = 0.83). The peri-procedural complication rate was very low. At 30-day and 12-month follow-up, the majority of patients were in NYHA functional class II or lower. The rate of death, stroke, and myocardial infarction (MACCE) was comparable in the three patient groups during 12-month follow-up (DCM 26.9 %, CAD 30.3 % and AV 27.5 %, p = 0.85). CONCLUSIONS: The MitraClip implantation is feasible and safe even in high-risk patients with MR and cardiac comorbidities.


Asunto(s)
Insuficiencia de la Válvula Aórtica/epidemiología , Cateterismo Cardíaco/métodos , Cardiomiopatía Dilatada/epidemiología , Enfermedad de la Arteria Coronaria/epidemiología , Prótesis Valvulares Cardíacas , Insuficiencia de la Válvula Mitral/epidemiología , Sistema de Registros , Anciano , Comorbilidad , Femenino , Estudios de Seguimiento , Alemania/epidemiología , Humanos , Masculino , Insuficiencia de la Válvula Mitral/diagnóstico , Insuficiencia de la Válvula Mitral/cirugía , Periodo Posoperatorio , Prevalencia , Estudios Prospectivos , Diseño de Prótesis , Factores de Riesgo , Factores de Tiempo
3.
JACC Cardiovasc Interv ; 9(1): 68-75, 2016 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-26762913

RESUMEN

OBJECTIVES: The aim of this study was to assess the 1-year outcome after transcatheter aortic valve replacement (TAVR) of the Direct Flow Medical (DFM) valve in patients with severe symptomatic aortic stenosis who were contraindicated or high risk for surgery. BACKGROUND: The DFM transcatheter heart valve is a new-generation, nonmetallic aortic valve with a pressurized support structure and conformable double-ring annular sealing delivered through an 18-F sheath. The device allows repositioning, retrieval, and assessment of valve performance before permanent implantation. METHODS: A prospective multicenter European registry was set up to determine the safety and performance of the valve in 100 consecutive patients (10 centers). Echocardiographic and angiographic data were evaluated by an independent core laboratory, and adverse events were adjudicated by a clinical events committee using Valve Academic Research Consortium criteria. RESULTS: Patients were 83.1 ± 5.9 years of age and had a logistic EuroSCORE of 22.5 ± 11.3% and a Society of Thoracic Surgeons score of 9.7 ± 8.7%. Correct valve positioning was obtained in 99% of cases with a combined 30-day safety endpoint at 10%, including major stroke in 5.0%, major vascular complications in 2.0%, and death in 1%. At 12 months, 95% of patients were in New York Heart Association functional class I or II. Freedom from any death was 90%, and freedom from any death or major stroke was 85%. Echocardiography demonstrated none/trace to mild aortic regurgitation in 100% of patients and an unchanged mean aortic gradient of 12.2 ± 6.6 mm Hg and effective orifice area of 1.6 ± 0.4 cm(2). CONCLUSIONS: At 1 year, the DFM transcatheter heart valve had durable hemodynamics. This study demonstrates that the low rate of early complications and the low risk of significant aortic regurgitation translated into midterm clinical benefit.


Asunto(s)
Estenosis de la Válvula Aórtica/terapia , Válvula Aórtica/fisiopatología , Bioprótesis , Cateterismo Cardíaco/instrumentación , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Prótesis Valvulares Cardíacas , Hemodinámica , Anciano , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/etiología , Insuficiencia de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/mortalidad , Estenosis de la Válvula Aórtica/fisiopatología , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/mortalidad , Supervivencia sin Enfermedad , Europa (Continente) , Femenino , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Diseño de Prótesis , Radiografía , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/etiología , Factores de Tiempo , Resultado del Tratamiento , Ultrasonografía
4.
EuroIntervention ; 11(10): 1148-52, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26549375

RESUMEN

AIMS: Transcatheter interventions with balloon-expandable valves have been shown to be efficacious for the treatment of mitral annuloplasty failure but are limited by the fact that there is no opportunity for post-implantation adjustment. The aim of this study was to assess the safety and efficacy of the fully repositionable and retrievable Direct Flow Medical (DFM) valve for the treatment of mitral annuloplasty failure. METHODS AND RESULTS: Patients who underwent transcatheter mitral valve-in-ring (VIR) implantation of a DFM valve for failed mitral annuloplasty deemed high risk for redo surgery were included at four institutions. Eight patients underwent transcatheter mitral VIR procedures with implantation of the DFM valve. The DFM prosthesis was successfully positioned in all patients. Two patients required retrieval of the device due to a suboptimal result, and a further patient required repositioning of the valve with an ultimately successful implantation. During the 30-day follow-up period, two patients died for reasons unrelated to the valve implantation. The four patients with successful implantation had normal valve function associated with a significant improvement in their functional status. CONCLUSIONS: For the first time, we demonstrate the safety, efficacy and advantages of using the DFM prosthesis for the treatment of mitral annuloplasty failure.


Asunto(s)
Válvula Aórtica/cirugía , Implantación de Prótesis de Válvulas Cardíacas , Anuloplastia de la Válvula Mitral , Insuficiencia de la Válvula Mitral/cirugía , Válvula Mitral/cirugía , Anciano , Anciano de 80 o más Años , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/instrumentación , Femenino , Prótesis Valvulares Cardíacas , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Masculino , Persona de Mediana Edad , Anuloplastia de la Válvula Mitral/instrumentación , Diseño de Prótesis , Resultado del Tratamiento
5.
PLoS One ; 7(3): e33939, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22479483

RESUMEN

BACKGROUND: Pro-inflammatory, cytotoxic CD4(+)CD28(-) T-cells with known defects in apoptosis have been investigated as markers of premature immuno-senescence in various immune-mediated diseases. In this study we evaluated the influence of polyclonal antilymphocyte globulins (ATG-Fresenius, ATG-F) on CD4(+)CD28(-) T-cells in vivo and in vitro. PRINCIPAL FINDINGS: Surface and intracellular three colour fluorescence activated cell sorting analyses of peripheral blood mononuclear cells from 16 consecutive transplant recipients and short-term cell lines were performed. In vivo, peripheral levels of CD3(+)CD4(+)CD28(-) T-cells decreased from 3.7 ± 7.1% before to 0 ± 0% six hours after ATG-F application (P = 0.043) in 5 ATG-F treated but not in 11 control patients (2.9 ± 2.9% vs. 3.9 ± 3.0%). In vitro, ATG-F induced apoptosis even in CD4(+)CD28(-) T-cells, which was 4.3-times higher than in CD4(+)CD28(+) T-cells. ATG-F evoked apoptosis was partially reversed by the broad-spectrum caspase inhibitor benzyloxycarbonyl (Cbz)-Val-Ala-Asp(OMe)-fluoromethylketone (zVAD-fmk) and prednisolon-21-hydrogensuccinate. ATG-F triggered CD25 expression and production of pro-inflammatory cytokines, and induced down-regulation of the type 1 chemokine receptors CXCR-3, CCR-5, CX3CR-1 and the central memory adhesion molecule CD62L predominately in CD4(+)CD28(-) T-cells. CONCLUSION: In summary, in vivo depletion of peripheral CD3(+)CD4(+)CD28(-) T-cells by ATG-F in transplant recipients was paralleled in vitro by ATG-F induced apoptosis. CD25 expression and chemokine receptor down-regulation in CD4(+)CD28(-) T-cells only partly explain the underlying mechanism.


Asunto(s)
Suero Antilinfocítico/farmacología , Apoptosis/efectos de los fármacos , Antígenos CD28/análisis , Linfocitos T CD4-Positivos/efectos de los fármacos , Factores Inmunológicos/farmacología , Adulto , Suero Antilinfocítico/inmunología , Apoptosis/inmunología , Complejo CD3 , Linfocitos T CD4-Positivos/inmunología , Caspasas/metabolismo , Citocinas/biosíntesis , Regulación hacia Abajo/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Femenino , Humanos , Factores Inmunológicos/inmunología , Inflamación/inmunología , Interleucina-2/metabolismo , Depleción Linfocítica , Masculino , Persona de Mediana Edad , Trasplante de Órganos , Receptores de Quimiocina/metabolismo , Transducción de Señal/efectos de los fármacos , Células TH1/efectos de los fármacos , Células TH1/inmunología , Migración Transendotelial y Transepitelial/efectos de los fármacos , Adulto Joven , Receptor fas/metabolismo
6.
Circ Cardiovasc Interv ; 4(6): 595-601, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22128202

RESUMEN

BACKGROUND: Misplacement during percutaneous aortic valve implantation can be associated with severe complications. The direct flow medical (DFM) valve is repositionable and retrievable; however, the nonmetallic inflatable and conformable design of the valve results in less radial force, which may have an impact on stability and valve function over time. We, therefore, analyzed the midterm stability of the position, shape, and hemodynamic performance of the DFM percutaneous aortic valve. METHODS AND RESULTS: Sixteen symptomatic high-risk for surgery patients with aortic stenosis and a logistic EuroSCORE >20 underwent implantation and were the subject of this analysis. Clinical, echocardiographic, and dual-source multislice computed tomography data were obtained during 2-year follow-up. The 1- and 2-year survival rates were 81% and 69%, respectively. The dual-source multislice computed tomography follow-up indicated no changes in position, diameter, and orifice area of the DFM valve over time. Echocardiography revealed a significant decrease of the mean gradient from baseline (50.1±11.3 mm Hg) to 30 days (19.6±5.7 mm Hg, P<0.001), which remained stable over 2 years. The aortic valve area increased from 0.57±0.15 cm(2) at baseline to 1.47±0.35 cm(2) at 30 days (P<0.001) and did not significantly change during 2-year follow-up. Of the patients, 73% had no aortic regurgitation (AR) and 27% had minimal AR. CONCLUSIONS: In this preliminary series, the 2-year follow-up data of patients, in whom the nonmetallic, repositionable, and retrievable DFM valve was successfully implanted, show stability of the position, shape, and hemodynamic performance, with no AR in most patients.


Asunto(s)
Angioplastia/métodos , Estenosis de la Válvula Aórtica/terapia , Válvula Aórtica/fisiología , Implantación de Prótesis de Válvulas Cardíacas/métodos , Prótesis Valvulares Cardíacas , Hemodinámica/fisiología , Índice de Severidad de la Enfermedad , Anciano , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/mortalidad , Estenosis de la Válvula Aórtica/fisiopatología , Ecocardiografía , Femenino , Vena Femoral , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Tomografía Computarizada Multidetector , Proyectos Piloto , Flujo Sanguíneo Regional/fisiología , Resultado del Tratamiento
7.
Am J Physiol Cell Physiol ; 293(1): C486-92, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17428840

RESUMEN

Interstitial inflammation has emerged as a key event in the development of acute renal failure. To gain better insight into the nature of these inflammatory processes, the interplay between tubular epithelial cells, endothelial cells, and neutrophils (PMN) was investigated. A coculture transmigration model was developed, composed of human dermal microvascular endothelial (HDMEC) and human renal proximal tubular cells (HK-2) cultured on opposite sides of Transwell growth supports. Correct formation of an endoepithelial bilayer was verified by light and electron microscopy. The model was used to study the effects of endotoxin (LPS), tumor necrosis factor (TNF)-alpha, and alpha-melanocyte-stimulating hormone (alpha-MSH) by measuring PMN migration and cytokine release. To distinguish between individual roles of microvascular endothelial and epithelial cells in transmigration processes, migration of PMN was investigated separately in HK-2 and HDMEC monolayers. Sequential migration of PMN through endothelium and epithelium could be observed and was significantly increased after proinflammatory stimulation with either TNF-alpha or LPS (3.5 +/- 0.58 and 2.76 +/- 0.64-fold vs. control, respectively). Coincubation with alpha-MSH inhibited the transmigration of PMN through the bilayer after proinflammatory stimulation with LPS but not after TNF-alpha. The bilayers produced significant amounts of IL-8 and IL-6 mostly released from the epithelial cells. Furthermore, alpha-MSH decreased LPS-induced IL-6 secretion by 30% but had no significant effect on IL-8 secretion. We established a transmigration model showing sequential migration of PMN across microvascular endothelial and renal tubular epithelial cells stimulated by TNF-alpha and LPS. Anti-inflammatory effects of alpha-MSH in this bilayer model are demonstrated by inhibition on PMN transmigration and IL-6 secretion.


Asunto(s)
Quimiotaxis de Leucocito , Células Endoteliales/inmunología , Células Epiteliales/inmunología , Túbulos Renales Proximales/inmunología , Leucocitos Mononucleares/inmunología , Nefritis Intersticial/inmunología , Piel/irrigación sanguínea , Línea Celular , Forma de la Célula , Técnicas de Cocultivo , Impedancia Eléctrica , Células Endoteliales/metabolismo , Células Epiteliales/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Túbulos Renales Proximales/citología , Túbulos Renales Proximales/metabolismo , Lipopolisacáridos/inmunología , Microcirculación/citología , Microcirculación/inmunología , Nefritis Intersticial/fisiopatología , Factores de Tiempo , Factor de Necrosis Tumoral alfa/inmunología , alfa-MSH/inmunología
8.
Exp Cell Res ; 312(15): 2933-41, 2006 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-16893539

RESUMEN

Growing evidence indicates that inducible cyclooxygenase-2 (COX-2) is involved in the pathogenesis of inflammatory disorders and various types of cancer. Endothelial progenitor cells recruited from the bone marrow have been shown to be involved in the formation of new vessels in malignancies and discussed for being a key point in tumour progression and metastasis. However, until now, nothing is known about an interaction between COX and endothelial progenitor cells (EPC). Expression of COX-1 and COX-2 was detected by semiquantitative RT-PCR and Western blot. Proliferation kinetics, cell cycle distribution and rate of apoptosis were analysed by MTT test and FACS analysis. Further analyses revealed an implication of Akt phosphorylation and caspase-3 activation. Both COX-1 and COX-2 expression can be found in bone-marrow-derived endothelial progenitor cells in vitro. COX-2 inhibition leads to a significant reduction in proliferation of endothelial progenitor cells by an increase in apoptosis and cell cycle arrest. COX-2 inhibition leads further to an increased cleavage of caspase-3 protein and inversely to inhibition of Akt activation. Highly proliferating endothelial progenitor cells can be targeted by selective COX-2 inhibition in vitro. These results indicate that upcoming therapy strategies in cancer patients targeting COX-2 may be effective in inhibiting tumour vasculogenesis as well as angiogenic processes.


Asunto(s)
Inhibidores de la Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/metabolismo , Células Endoteliales/enzimología , Pirazoles/farmacología , Células Madre/enzimología , Sulfonamidas/farmacología , Animales , Apoptosis/efectos de los fármacos , Aspirina/metabolismo , Aspirina/farmacología , Caspasa 3 , Caspasa 8 , Caspasas/metabolismo , Celecoxib , Proliferación Celular/efectos de los fármacos , Ciclooxigenasa 1/metabolismo , Inhibidores de la Ciclooxigenasa 2/metabolismo , Diclofenaco/metabolismo , Diclofenaco/farmacología , Relación Dosis-Respuesta a Droga , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica , Masculino , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/metabolismo , Proteína Oncogénica v-akt/metabolismo , Fosforilación , Pirazoles/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Células Madre/citología , Sulfonamidas/metabolismo
9.
Cell Physiol Biochem ; 17(5-6): 233-44, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16790999

RESUMEN

BACKGROUND: Adhesion of intratubular leukocytes to proximal tubules in biopsies of patients with rapidly progressive glomerulonephritis and the appearance of leukocytes in the urine in interstitial nephritis suggest interactions between leukocytes and tubular epithelia in renal diseases. The aim of this study was to investigate the effect of cytokines and endotoxin on leukocyte migration through proximal tubular epithelial cells and also to determine the role of the transmembrane adhesion molecules ICAM-1 and CD47 in this process. METHODS: Experiments determined transepithelial migration (TEM) of PMN (polymorphonuclear) leukocytes through monolayers of HK-2. Expression of ICAM-1 and CD47 was assessed via confocal immunofluorescence, FACS analysis and western blotting. The effect of antibodies against ICAM-1 and CD47 on TEM was examined. Furthermore measurements of cytokine release (IL- 6 and IL-8) were performed. RESULTS: Preincubation of HK-2 cells with either TNFalpha or LPS resulted in stimulation of PMN migration through monolayers of HK-2 cells. There was no preferred direction of transmigration. ICAM-1 was expressed by HK-2 cells and expression was increased after 4 h stimulation with TNFalpha or LPS. Application of ICAM-1 antibodies inhibited TEM. CD47 was expressed in both HK-2 cells and PMN. CD47 antibodies inhibited predominantly basolateral-to-apical TEM. HK-2 cells released IL-8 and IL-6 preferably into the apical compartment. Additionally, we showed that fMLP induced transmigration through monolayers of HK-2 cells was associated with significant increased CD47 expression on PMN cell surfaces. CONCLUSIONS: Inflammatory mediators stimulate TEM of PMN through monolayers of HK-2 cells without a clearly discernible preference of direction. Mechanisms involved in TEM stimulated by cytokines or endotoxin appear to be mainly changes in surface receptor densities of HK-2 cells with ICAM-1 and CD47 playing an essential role.


Asunto(s)
Movimiento Celular/fisiología , Túbulos Renales Proximales/citología , Neutrófilos/citología , Anticuerpos Monoclonales/farmacología , Antígeno CD47/efectos de los fármacos , Antígeno CD47/inmunología , Antígeno CD47/metabolismo , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Quimiotaxis de Leucocito , Citocinas/metabolismo , Células Epiteliales/citología , Células Epiteliales/metabolismo , Humanos , Molécula 1 de Adhesión Intercelular/efectos de los fármacos , Molécula 1 de Adhesión Intercelular/metabolismo , Túbulos Renales Proximales/efectos de los fármacos , Lipopolisacáridos/farmacología , Microscopía Fluorescente , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Factor de Necrosis Tumoral alfa/farmacología
10.
Microcirculation ; 12(5): 393-403, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16020388

RESUMEN

OBJECTIVE: After an ischemic event vascular growth factors are involved in regulating leukocyte infiltration in inflammatory processes. This study focused on effects of 2 other angiogenic growth factors, angiopoietin-1 and angiopoietin-2, on human neutrophils and on the involvement of the angiopoietin receptor Tie-2. METHODS: Neutrophils were from venous blood of healthy donors and cell migration was studied by micropore filter assays. Receptor expression was investigated by reverse transcriptase-polymerase chain reaction (PCR) for mRNA and fluorescence-activated cell-sorter scanner (FACS) analysis. Signaling mechanisms required for angiopoietin-dependent effects were tested functionally by using signaling enzyme blockers. RESULTS: The angiopoietins were chemotactic for neutrophils. They showed antagonistic effects on each other and both inhibited VEGF-directed migration of neutrophils. The effects of both angiopoietins were Tie-2 dependent. Tie-2 receptor immunoreactivity was confirmed on neutrophils by FACS. De novo synthesis is suggested by Tie-2 receptor mRNA expression as demonstrated by reverse transcriptase PCR. CONCLUSIONS: Data suggest that a Tie-2 receptor is expressed by human neutrophils whose active site ligation with either angiopoietin-1 or angiopoietin-2 exerts migratory effects on the one hand and arrests VEGF-mediated chemotaxis on the other. These effects suggest a role of angiopoietins in modulating neutrophilic inflammation.


Asunto(s)
Angiopoyetina 1/fisiología , Angiopoyetina 2/fisiología , Quimiotaxis , Neutrófilos/fisiología , Receptor TIE-2/fisiología , Células Cultivadas , Humanos , Inflamación/patología , ARN Mensajero/análisis , Receptor TIE-2/genética , Transducción de Señal , Factor A de Crecimiento Endotelial Vascular/farmacología
11.
J Allergy Clin Immunol ; 114(5): 1077-84, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15536413

RESUMEN

BACKGROUND: Increased vascularity of bronchial mucosa is closely related to the expression of angiogenic factors, which contribute to the pathogenesis of diseases such as asthma bronchiale. OBJECTIVE: Here we examine the effects of the angiogenic growth factors angiopoietin 1 and angiopoietin 2 on eosinophil function in vitro and possible involvement of the angiopoietin receptor Tie-2. METHODS: Eosinophil migration was studied by micropore filter assays. Signaling mechanisms required for angiopoietin-dependent migration were tested by using signaling enzyme blockers. Tie-2 mRNA and receptor expression on the cell surface of eosinophils was demonstrated in RT-PCR and by fluorescence-activated cell sorting analysis. RESULTS: Angiopoietin 1 significantly stimulated eosinophil chemotaxis via activation of phosphodiesterase, phosphatidylinositol 3'-kinase, and tyrosine kinases. The effect on eosinophil migration of angiopoietin 1 was reversed by an antibody against the Tie-2 receptor and by angiopoietin 2. Incubation of eosinophils with angiopoietin 1 abolished the chemotactic effects of vascular endothelial growth factor on human eosinophils via the Tie-2 receptor. Finally, Tie-2 expression by human eosinophils was demonstrated on the transcriptional and protein level. CONCLUSIONS: Data suggest that angiopoietin 1 stimulates directed migration and possibly inhibits vascular endothelial growth factor-induced eosinophil chemotaxis via its Tie-2 receptor, which is expressed by eosinophils. Thus, angiopoietin 1 may play an important role in the modulation of eosinophilic inflammation.


Asunto(s)
Eosinófilos/fisiología , Receptor TIE-2/fisiología , 1-Metil-3-Isobutilxantina/farmacología , Angiopoyetina 1/farmacología , Angiopoyetina 2/farmacología , Movimiento Celular/efectos de los fármacos , Quimiotaxis/efectos de los fármacos , Eosinófilos/efectos de los fármacos , Humanos , Fosfatidilinositol 3-Quinasas/fisiología , ARN Mensajero/análisis , Receptor TIE-2/genética , Factor A de Crecimiento Endotelial Vascular/farmacología
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