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1.
Phys Rev Lett ; 131(9): 092502, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37721815

RESUMEN

We successfully performed electron scattering off unstable nuclei which were produced online from the photofission of uranium. The target ^{137}Cs ions were trapped with a new target-forming technique that makes a high-density stationary target from a small number of ions by confining them in an electron storage ring. After developments of target generation and transportation systems and the beam stacking method to increase the ion beam intensity up to approximately 2×10^{7} ions per pulse beam, an average luminosity of 0.9×10^{26} cm^{-2} s^{-1} was achieved for ^{137}Cs. The obtained angular distribution of elastically scattered electrons is consistent with a calculation. This success marks the realization of the anticipated femtoscope which clarifies the structures of exotic and short-lived unstable nuclei.

2.
Clin Exp Allergy ; 48(3): 278-287, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29315896

RESUMEN

BACKGROUND: Respiratory impedance comprises the resistance and reactance of the respiratory system and can provide detailed information on respiratory function. However, details of the relationship between impedance and morphological airway changes in asthma are unknown. OBJECTIVE: We aimed to evaluate the correlation between imaging-based airway changes and respiratory impedance in patients with asthma. METHODS: Respiratory impedance and spirometric data were evaluated in 72 patients with asthma and 29 reference subjects. We measured the intraluminal area (Ai) and wall thickness (WT) of third- to sixth-generation bronchi using three-dimensional computed tomographic analyses, and values were adjusted by body surface area (BSA, Ai/BSA, and WT/the square root (√) of BSA). RESULTS: Asthma patients had significantly increased respiratory impedance, decreased Ai/BSA, and increased WT/√BSA, as was the case in those without airflow limitation as assessed by spirometry. Ai/BSA was inversely correlated with respiratory resistance at 5 Hz (R5) and 20 Hz (R20). R20 had a stronger correlation with Ai/BSA than did R5. Ai/BSA was positively correlated with forced expiratory volume in 1 second/forced vital capacity ratio, percentage predicted forced expiratory volume in 1 second, and percentage predicted mid-expiratory flow. WT/√BSA had no significant correlation with spirometry or respiratory impedance. CONCLUSIONS & CLINICAL RELEVANCE: Respiratory resistance is associated with airway narrowing.


Asunto(s)
Asma/diagnóstico por imagen , Asma/fisiopatología , Imagenología Tridimensional/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Resistencia de las Vías Respiratorias/fisiología , Impedancia Eléctrica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Función Respiratoria , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
4.
Phys Rev Lett ; 118(26): 262501, 2017 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-28707914

RESUMEN

The first elastic electron scattering has been successfully performed at the self-confining radioactive-isotope ion target (SCRIT) facility, the world's first electron scattering facility for SCRIT technique achieved high luminosity (over 10^{27} cm^{-2} s^{-1}, sufficient for determining the nuclear shape) with only 10^{8} target ions. While ^{132}Xe used in this time as a target is a stable isotope, the charge density distribution was first extracted from the momentum transfer distributions of the scattered electrons by comparing the results with those calculated by a phase shift calculation.

6.
Clin Exp Immunol ; 177(1): 110-20, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24580543

RESUMEN

Dermatomyositis (DM) and polymyositis (PM) are collectively termed autoimmune myopathy. To investigate the difference between muscle- and skin-infiltrating T cells and to address their role for myopathy, we characterized T cells that were directly expanded from the tissues. Enrolled into this study were 25 patients with DM and three patients with PM. Muscle and skin biopsied specimens were immersed in cRPMI medium supplemented with interleukin (IL)-2 and anti-CD3/CD28 antibody-conjugated microbeads. The expanded cells were subjected to flow cytometry to examine their phenotypes. We analysed the cytokine concentration in the culture supernatants from the expanded T cells and the frequencies of cytokine-bearing cells by intracellular staining. There was non-biased in-vitro expansion of tissue-infiltrating CD4(+) and CD8(+) T cells from the muscle and skin specimens. The majority of expanded T cells were chemokine receptor (CCR) type 7(-) CD45RO(+) effecter memory cells with various T cell receptor (TCR) Vßs. The skin-derived but not muscle-derived T cells expressed cutaneous lymphocyte antigen (CLA) and CCR10 and secreted large amounts of IL-17A, suggesting that T helper type 17 (Th17) cells may have a crucial role in the development of skin lesions. Notably, the frequency of IL-4-producing chemokine (C-X-C motif) receptor (CXCR)4(+) Th2 cells was significantly higher in the muscle-derived cells and correlated inversely with the serum creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) levels. stromal-derived factor (SDF)-1/CXCL12, a ligand for CXCR4, was expressed at a high level in the vascular endothelial cells between muscular fasciculi. Our study suggests that T cell populations in the muscle and skin are different, and the Th2 cell infiltrate in the muscle is associated with the low severity of myositis in DM.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Dermatomiositis/inmunología , Músculos/inmunología , Piel/inmunología , Células Th2/inmunología , Adulto , Anciano , Antígenos de Diferenciación de Linfocitos T/metabolismo , Movimiento Celular , Separación Celular , Células Cultivadas , Quimiocina CXCL12/metabolismo , Femenino , Citometría de Flujo , Humanos , Memoria Inmunológica , Inmunofenotipificación , Interleucina-17/metabolismo , Interleucina-4/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , Persona de Mediana Edad , Receptores CCR10/metabolismo , Receptores CXCR4/metabolismo
7.
Dev Dyn ; 242(2): 179-88, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23192966

RESUMEN

BACKGROUND: In the cochlea, patterning of the organ of Corti is tightly regulated to produce a single row of sound-detecting inner hair cells and three rows of outer hair cells, which amplify and refine the signal. The recently identified R-Spondin family of signaling molecules usually act as co-activators of Wnt signaling; it is thought that they regulate turnover of Wnt receptors at the membrane. We sought to test whether R-Spondins function in the developing cochlea. RESULTS: Expression analysis of all four members of the R-Spondin family showed that only R-Spondin2 (Rspo2) is expressed in the cochlea during development of the sensory epithelium. Examination of an Rspo2(-/-) mouse showed that loss of Rspo2 results in an additional single row of outer hair cells and disruption of peripheral innervation pattern. Addition of Rspo2 recombinant protein to organotypic cochlear cultures resulted in a small but significant decrease in the number of outer hair cells. CONCLUSIONS: Rspo2 is required to limit the number of outer hair cells to three rows and for optimal arrangement of peripheral nerve fibers. The Rspo2 gain- and loss-of-function studies show that in the ear, Rspo2 function is not consistent with its assigned role as a Wnt potentiator.


Asunto(s)
Cóclea/embriología , Regulación del Desarrollo de la Expresión Génica/fisiología , Morfogénesis/fisiología , Trombospondinas/metabolismo , Animales , Cóclea/metabolismo , Cartilla de ADN/genética , Técnica del Anticuerpo Fluorescente , Regulación del Desarrollo de la Expresión Génica/genética , Células Ciliadas Auditivas/fisiología , Procesamiento de Imagen Asistido por Computador , Hibridación in Situ , Ratones , Ratones Noqueados , Microscopía Confocal , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trombospondinas/genética
8.
Gene Ther ; 20(8): 816-23, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23344066

RESUMEN

The development of a safe and reproducible gene delivery system is an essential step toward the clinical application of the hydrodynamic gene delivery (HGD) method. For this purpose, we have developed a novel electric power-driven injection system called the HydroJector-EM, which can replicate various time-pressure curves preloaded into the computer program before injection. The assessment of the reproducibility and safety of gene delivery system in vitro and in vivo demonstrated the precise replication of intravascular time-pressure curves and the reproducibility of gene delivery efficiency. The highest level of luciferase expression (272 pg luciferase per mg of proteins) was achieved safely using the time-pressure curve, which reaches 30 mm Hg in 10 s among various curves tested. Using this curve, the sustained expression of a therapeutic level of human factor IX protein (>500 ng ml(-1)) was maintained for 2 months after the HGD of the pBS-HCRHP-FIXIA plasmid. Other than a transient increase in liver enzymes that recovered in a few days, no adverse events were seen in rats. These results confirm the effectiveness of the HydroJector-EM for reproducible gene delivery and demonstrate that long-term therapeutic gene expression can be achieved by automatic computer-controlled hydrodynamic injection that can be performed by anyone.


Asunto(s)
Factor IX/genética , Técnicas de Transferencia de Gen , Vectores Genéticos , Animales , Expresión Génica , Humanos , Hidrodinámica , Inyecciones , Hígado/metabolismo , Luciferasas/metabolismo , Ratas
9.
Clin Exp Allergy ; 43(5): 521-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23600542

RESUMEN

BACKGROUND: Clinical application of the forced oscillation technique (FOT) has progressed with the spread of commercially available FOT devices. The correlation between respiratory impedance and spirometry has been reported; however, the association with airway inflammation and pulmonary function, in the lung periphery in particular, is unclear. OBJECTIVE: To assess whether respiratory impedance is associated with peripheral airway inflammation and dysfunction in asthma. METHODS: Subjects included 78 patients with overall controlled asthma. We measured whole-breath or within-breath respiratory system resistance (Rrs) and reactance (Xrs) using a commercially available multi-frequency FOT device (MostGraph-01), and assessed the correlation with the fraction of exhaled nitric oxide (FeNO), alveolar nitric oxide concentration (CANO), maximal NO flux in the conductive airways (J'awNO), and the N2 phase III slope of single breath N2 washout (delta N2 ). RESULTS: The differences between inspiratory and expiratory phases of Xrs at 5 Hz (X5), resonant frequency (Fres), and a low-frequency reactance area (ALX) were significantly correlated with CANO; however, there was no correlation between respiratory impedance and FeNO or J'awNO. The delta N2 values were significantly correlated with whole-breath, inspiratory, and expiratory Rrs and Xrs, except for R20. CONCLUSIONS AND CLINICAL RELEVANCE: We conclude that respiratory impedance reflects peripheral airway inflammation and ventilation inhomogeneity.


Asunto(s)
Asma/fisiopatología , Mecánica Respiratoria , Adulto , Anciano , Estudios de Casos y Controles , Espiración , Femenino , Humanos , Masculino , Persona de Mediana Edad , Óxido Nítrico , Pruebas de Función Respiratoria , Factores de Riesgo
10.
J Viral Hepat ; 19(2): e212-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22239521

RESUMEN

Acoustic Radiation Force Impulse (ARFI) imaging is a novel ultrasound-based elastography method that is integrated in a conventional ultrasound machine enabling the exact localization of measurement site. It might present an alternative method to transient elastography for the noninvasive assessment of liver fibrosis. At present, studies with small patient population have shown promising results. A systematic review and meta-analysis of pooled patient data were performed to evaluate the overall performance of ARFI for the staging of liver fibrosis. Literature databases were searched up to 10/2010. The authors of the original publication were contacted, and the original patient data were requested. A meta-analysis was performed using a random effect meta-analytic method for diagnostic tests. In addition, available data comparing ARFI with FibroScan with the DeLong test were evaluated. Literature search yielded nine full-paper publications evaluating ARFI while using liver biopsy as reference method. Original patient data were available from eight studies including 518 patients. The mean diagnostic accuracy of ARFI expressed as areas under ROC curves (AUROC) was 0.87 for the diagnosis of significant fibrosis (F ≥ 2), 0.91 for the diagnosis of severe fibrosis (F ≥ 3), and 0.93 for the diagnosis of cirrhosis. ARFI can be performed with good diagnostic accuracy for the noninvasive staging of liver fibrosis.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/patología , Hígado/diagnóstico por imagen , Hígado/patología , Índice de Severidad de la Enfermedad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
11.
Sarcoidosis Vasc Diffuse Lung Dis ; 29(1): 69-73, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23311128

RESUMEN

BACKGROUND: Pulmonary dendritic cells (DCs) are key regulators of immune responses. An increased accumulation of DCs was reported in the lungs of patients with idiopathic interstitial pneumonia (IIP). OBJECTIVE: This study aimed to investigate the number of pulmonary DCs in patients with collagen vascular disease associated interstitial lung diseases (CVD-ILDs). DESIGN: Lung tissue samples obtained from 27 patients with IIP and 39 patients with CVD-ILD were detected using monoclonal antibodies against CD1a, CD1c, CD83, Langerin and DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN). RESULTS: No significant differences in the number or distribution of DCs were observed between patients with IIP and CVD-ILDs. When DC marker expression was analyzed according to pathological subgroup, patients with idiopathic usual interstitial pneumonia (UIP) showed increased DC-SIGN staining when compared with CVD-UIP (p < 0.05). CONCLUSION: Both mature and immature DCs accumulate in CVD-ILDs. The number of DCs expressing DC-SIGN in CVD-UIP was decreased compared with that in idiopathic UIP. The variation in accumulated DC-SIGN-positive cells might help to explain the differences in the development and maintenance of lung inflammation between idiopathic UIP and CVD-UIP.


Asunto(s)
Células Dendríticas/inmunología , Fibrosis Pulmonar Idiopática/inmunología , Enfermedades Pulmonares Intersticiales/inmunología , Pulmón/inmunología , Anciano , Anciano de 80 o más Años , Antígenos CD/análisis , Antígenos CD1/análisis , Biomarcadores/análisis , Biopsia , Moléculas de Adhesión Celular/análisis , Femenino , Glicoproteínas/análisis , Humanos , Fibrosis Pulmonar Idiopática/clasificación , Fibrosis Pulmonar Idiopática/patología , Inmunoglobulinas/análisis , Lectinas Tipo C/análisis , Pulmón/patología , Enfermedades Pulmonares Intersticiales/clasificación , Enfermedades Pulmonares Intersticiales/patología , Masculino , Lectinas de Unión a Manosa/análisis , Glicoproteínas de Membrana/análisis , Persona de Mediana Edad , Receptores de Superficie Celular/análisis , Antígeno CD83
12.
Eur Respir J ; 37(2): 371-5, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20530033

RESUMEN

There are very few data on serum procalcitonin (PCT) levels in pulmonary tuberculosis (PTB) patients who are negative for HIV. We assessed serum PCT in consecutive patients diagnosed with pulmonary tuberculosis or community-acquired pneumonia (CAP) on admission to discriminate between PTB and CAP, and examined the value of prognostic factors in PTB. 102 PTB patients, 62 CAP patients, and 34 healthy volunteers were enrolled. Serum PCT in PTB patients was significantly lower than in CAP patients (mean ± sd 0.21 ± 0.49 versus 4.10 ± 8.68 ng·mL⁻¹; p < 0.0001). By receiver-operating characteristic curve analysis, serum PCT was an appropriate discrimination marker for PTB and CAP (area under the curve 0.866). PTB patients with ≥ 0.5 ng·mL⁻¹ (normal cut-off) had significantly shorter survival than those with < 0.5 ng·mL⁻¹ (p < 0.0001). Serum PCT is not habitually elevated in HIV-negative PTB patients and is a useful biomarker for discriminating between PTB and CAP; however, when serum PCT is outside the normal range, it is a poor prognostic marker.


Asunto(s)
Calcitonina/sangre , Neumonía Bacteriana/diagnóstico , Precursores de Proteínas/sangre , Tuberculosis Pulmonar/sangre , Tuberculosis Pulmonar/diagnóstico , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Péptido Relacionado con Gen de Calcitonina , Infecciones Comunitarias Adquiridas/sangre , Infecciones Comunitarias Adquiridas/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neumonía Bacteriana/sangre , Pronóstico , Curva ROC , Índice de Severidad de la Enfermedad
13.
Nat Med ; 3(4): 409-13, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9095174

RESUMEN

The Fas ligand (FasL) is expressed in activated T cells and induces apoptosis in Fas-bearing cells. A cytotoxic T lymphocyte (CTL) clone specific for hepatitis B surface antigen (HBsAg) causes an acute liver disease in HBsAg transgenic mice. Here we observed that the CTL clone killed hepatocytes expressing HBsAg in a Fas-dependent manner. Administration of the soluble form of Fas into HBsAg transgenic mice prevented the CTL-induced liver disease. In the second model, mice were primed with Propionibacterium acnes. A subsequent challenge with lipopolysaccharide (LPS) killed the mice by inducing liver injury. Neutralization of FasL rescued the mice from LPS-induced mortality, and Fas-null mice were resistant to LPS-induced mortality. These results suggest that FasL has an essential role in the development of hepatitis.


Asunto(s)
Encefalopatía Hepática/etiología , Glicoproteínas de Membrana/metabolismo , Receptor fas/metabolismo , Animales , Citotoxicidad Inmunológica , Endotoxinas/farmacología , Proteína Ligando Fas , Encefalopatía Hepática/inmunología , Encefalopatía Hepática/mortalidad , Encefalopatía Hepática/prevención & control , Antígenos de Superficie de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/inmunología , Ratones , Ratones Transgénicos , Solubilidad , Análisis de Supervivencia , Linfocitos T Citotóxicos , Receptor fas/farmacología
14.
Nat Med ; 4(11): 1287-92, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9809553

RESUMEN

Fas ligand is a well-characterized apoptosis inducer. Here we demonstrate that Fas ligand induces the processing and secretion of interleukin-1beta (IL-1beta) in peritoneal exudate cells. This IL-1beta secretion is independent of IL-1beta converting enzyme (caspase 1), yet it is inhibited by caspase inhibitors, indicating that a caspase(s) in addition to IL-1beta converting enzyme can process IL-1beta. Inoculation of tumor cells expressing Fas ligand into wild-type mice induces a massive neutrophil infiltration that is, in contrast, suppressed in IL-1alpha/beta knockout mice. These results demonstrate a newly discovered role for Fas ligand in inflammation, and challenge the dogma that apoptosis does not induce inflammation.


Asunto(s)
Apoptosis , Caspasa 1/metabolismo , Inflamación/fisiopatología , Interleucina-1/biosíntesis , Glicoproteínas de Membrana/fisiología , Receptor fas/fisiología , Animales , Caspasa 1/deficiencia , Caspasa 1/genética , Células Cultivadas , Cruzamientos Genéticos , Proteína Ligando Fas , Femenino , Fibrosarcoma/inmunología , Fibrosarcoma/patología , Homocigoto , Inflamación/inmunología , Interleucina-1/deficiencia , Interleucina-1/genética , Linfocitos/inmunología , Masculino , Glicoproteínas de Membrana/biosíntesis , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Ratones Noqueados , Neutrófilos/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Bazo/inmunología
15.
Nat Med ; 2(3): 317-22, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8612231

RESUMEN

The Fas ligand (FasL), a member of the tumor necrosis factor family, induces apoptosis in Fas-bearing cells. The membrane-bound human FasL was found to be converted to a soluble form (sFasL) by the action of a matrix metalloproteinase-like enzyme. Two neutralizing monoclonal anti-human FasL antibodies were identified, and an enzyme-linked immunosorbent assay (ELISA) for sFasL in human sera was established. Sera from healthy persons did not contain a detectable level of sFasL, whereas those from patients with large granular lymphocytic (LGL) leukemia and natural killer (NK) cell lymphoma did. These malignant cells constitutively expressed FasL, whereas peripheral NK cells from healthy persons expressed FasL only on activation. These results suggested that the systemic tissue damage seen in most patients with LGL leukemia and NK-type lymphoma is due to sFasL produced by these malignant cells. Neutralizing anti-FasL antibodies or matrix metalloproteinase inhibitors may be of use in modulating such tissue damage.


Asunto(s)
Glicoproteínas de Membrana/sangre , Animales , Anticuerpos Monoclonales , Secuencia de Bases , Cartilla de ADN , Ensayo de Inmunoadsorción Enzimática , Proteína Ligando Fas , Humanos , Técnicas In Vitro , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Leucemia de Células T/sangre , Leucemia de Células T/inmunología , Ligandos , Activación de Linfocitos , Linfoma/sangre , Linfoma/genética , Linfoma/inmunología , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/inmunología , Metaloendopeptidasas/metabolismo , Ratones , Datos de Secuencia Molecular , Pruebas de Neutralización , Solubilidad , Linfocitos T/inmunología , Linfocitos T/metabolismo , Transformación Genética
16.
Clin Transl Oncol ; 23(2): 418-423, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32533317

RESUMEN

PURPOSE: Tryptophan metabolites have immunomodulatory functions, suggesting possible roles in cancer immunity. METHODS: Plasma tryptophan metabolites were measured using liquid chromatography/mass spectrometry before immune checkpoint inhibitors (ICIs) in patients with non-small cell lung cancer (NSCLC). RESULTS: The 19 patients with NSCLC had significantly lower levels of tryptophan (p = 0.002) and xanthurenic acid (p = 0.032), and a significantly higher level of 3-hydroxyanthranilic acid (3-HAA) (p = 0.028) compared with the 10 healthy volunteers. The patients achieving objective responses had significantly lower levels of 3-HAA than those who did not (p = 0.045). Receiver operating characteristic analyses determined that the cutoff value of 3-HAA for objective response was 35.4 pmol/mL (sensitivity: 87.5% and specificity: 83.3%). The patients with 3-HAA < 35.4 pmol/mL had significantly longer median progression-free survival (7.0 months) than those without (1.6 months, p = 0.022). CONCLUSIONS: Tryptophan metabolites may have a potential for predicting the efficacy of ICIs. REGISTRATION NUMBER: University Hospital Medical Information Network Clinical Trial Registry 000026140.


Asunto(s)
Ácido 3-Hidroxiantranílico/análisis , Carcinoma de Pulmón de Células no Pequeñas/sangre , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Pulmonares/sangre , Triptófano/sangre , Xanturenatos/sangre , Adulto , Anciano , Anciano de 80 o más Años , Antígeno B7-H1/sangre , Antígeno B7-H1/metabolismo , Biomarcadores/sangre , Biomarcadores/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Supervivencia sin Progresión , Estudios Prospectivos , Curva ROC , Análisis de Regresión , Sensibilidad y Especificidad , Resultado del Tratamiento , Triptófano/metabolismo
17.
J Exp Med ; 179(3): 873-9, 1994 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-7509364

RESUMEN

Fas is a 45-kD cell surface protein belonging to the tumor necrosis factor/nerve growth factor receptor family, and transduces the signal for apoptosis. The cytotoxic T lymphocyte (CTL) hybridoma, PC60-d10S requires the presence of Fas on target cells to induce cytolysis in target cells. This CTL cell line was weakly but specifically stained by a chimeric protein that consisted of the extracellular domain of mouse Fas and the Fc portion of human immunoglobulin G1 (mFas-Fc). Moreover, mFas-Fc inhibited the cytotoxic activity of PC60-d10S. Sublines of d10S that were stained intensively by mFas-Fc were isolated by repetitive fluorescence-activated cell sorter sorting. A cell-surface protein of about 40 kD was specifically precipitated by mFas-Fc from the lysates of these sublines. This protein was homogeneously purified by sequential affinity chromatographies using mFas-Fc and concanavalin A beads. The purified protein exhibited cytotoxic activity against cells expressing Fas but not to the cells which do not express Fas. These results indicated that the 40-kD membrane glycoprotein expressed on PC60-d10S cells is the Fas-ligand that induces the apoptotic signal by binding to Fas.


Asunto(s)
Antígenos de Superficie/metabolismo , Apoptosis , Glicoproteínas de Membrana/aislamiento & purificación , Proteínas de la Membrana/aislamiento & purificación , Linfocitos T Citotóxicos/inmunología , Animales , Antígenos de Superficie/biosíntesis , Secuencia de Bases , Cromatografía de Afinidad , Concanavalina A , Cartilla de ADN , Electroforesis en Gel de Poliacrilamida , Humanos , Hibridomas/inmunología , Fragmentos Fc de Inmunoglobulinas/análisis , Fragmentos Fc de Inmunoglobulinas/metabolismo , Inmunoglobulina G/análisis , Inmunoglobulina G/metabolismo , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/fisiología , Proteínas de la Membrana/metabolismo , Ratones , Datos de Secuencia Molecular , Peso Molecular , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes de Fusión/análisis , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal , Receptor fas
18.
J Exp Med ; 181(2): 485-91, 1995 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-7530758

RESUMEN

Fas is a cell surface protein that mediates apoptosis. A mouse mutant, lpr (lymphoproliferation), has a mutation in the Fas gene. In this report, we studied the expression and function of Fas in various subpopulations of mouse thymocytes. Abundant expression of Fas was detected on CD4+CD8+ double positive as well as CD4+ or CD8+ single positive thymocytes in wild-type mice. Little or low levels of Fas were expressed in CD4-CD8- double negative thymocytes except for the CD4-CD8-CD3+ phenotype, which expresses Fas as abundantly as double positive or single positive subsets. On the other hand, no Fas expression was detected in any population of thymocytes from lpr mice. When the wild-type thymocytes were treated with the agonistic anti-Fas antibody, double positive cells from the wild-type mice were selectively killed by apoptosis, whereas, the single positive cells were resistant to its cytolytic activity despite their abundant expression of Fas. Unlike the apoptosis of thymocytes induced by glucocorticoid or T cell activator, the Fas-induced apoptosis of thymocytes was enhanced by metabolic inhibitors such as cycloheximide. Furthermore, intraperitoneal administration of the anti-Fas antibody into mice caused rapid apoptosis of thymocytes in vivo.


Asunto(s)
Antígenos de Superficie/fisiología , Apoptosis , Antígenos CD4 , Antígenos CD8 , Timo/citología , Animales , Antígenos de Superficie/genética , Antígenos de Superficie/inmunología , Diferenciación Celular , Células Cultivadas , Cricetinae , Citotoxicidad Inmunológica , Ratones , Ratones Endogámicos BALB C , Timo/inmunología , Timo/metabolismo , Receptor fas
19.
J Exp Med ; 186(12): 2045-50, 1997 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-9396774

RESUMEN

It has been believed that the Fas expressed on human peripheral blood T cells (PBT) is nonfunctional, because these cells are insensitive to agonistic anti-Fas/Apo-1 mAbs that efficiently kill in vitro-activated T cells and many Fas-expressing cell lines. Here, we demonstrate that membrane-bound Fas ligand (FasL) kills both fresh and in vitro-activated PBT, indicating that the Fas expressed on fresh PBT is functional. In contrast, soluble FasL kills only the latter. Naive T cells in umbilical cord blood do not express Fas, but can be induced to express Fas by IFN-gamma or by a combination of IL-2 and anti-CD28 mAb, after which they acquire sensitivity to membrane but not to soluble FasL. Soluble FasL inhibited the killing of fresh PBT by membrane FasL. These results indicate that the shedding of FasL from the membrane is a mechanism for downregulating at least part of its killing activity.


Asunto(s)
Apoptosis , Glicoproteínas de Membrana/farmacología , Linfocitos T/efectos de los fármacos , Receptor fas/farmacología , Adulto , Anticuerpos Monoclonales/farmacología , Apoptosis/efectos de los fármacos , Antígenos CD28/inmunología , Proteína Ligando Fas , Humanos , Interferón gamma/farmacología , Interleucina-2/farmacología , Ligandos , Solubilidad , Linfocitos T/citología
20.
J Exp Med ; 167(3): 762-76, 1988 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-3258352

RESUMEN

Blast colonies were developed by rIL-3 from the spleen cells of mice pretreated with 5-fluorouracil (5-FU) in the methylcellulose cultures. When such IL-3-induced blast colonies were individually lifted up and recultured in the presence of rIL-3 and recombinant erythropoietin (rEpo), a variety of hematopoietic colonies developed from every single colony, including neutrophils, macrophages, eosinophils, megakaryocytes, mast cells, and erythroblasts. The results indicated that IL-3-induced blast colonies consisted of multipotential hematopoietic progenitor cells. By culturing individual IL-3-induced blast colonies in the presence of rIL-2 and irradiated peritoneal macrophages, on the other hand, the proliferation of homogeneous lymphoid cells was observed in 5 of 24 wells, each of which received a single blast colony. Morphologically, they were typical large granular lymphocytes (LGL), and thus it was indicated that LGL could be differentiated directly from the hematopoietic progenitor cells utterly in vitro by rIL-2 and accessory macrophages. From one of these culture wells, a continuous LGL line, IL3B1, was successfully obtained. The proliferation of IL3B1 was dependent on IL-2 in the presence of accessory macrophages, but they no longer responded to IL-3, nor to another T cell growth factor, IL-4. Flow cytometric analysis indicated that the phenotype of IL3B1 was Thy-1+,T3+,L3T4-,Lyt-2-,T200+ Asialo GM1+, whereas that of original IL-3-induced blast cells was Thy-1+,T3-,L3T4-,Lyt-2-,B220-. The results suggested that the expression of T3 molecules was induced in the process of LGL differentiation from the hematopoietic progenitor cells in vitro. Conforming to this, it was revealed that both gamma and beta chain genes of the TCR were rearranged in IL3B1. Northern blot analysis indicated that IL3B1 had abundant mRNA for gamma chain, while mRNA for beta chain was rather faint. Functionally, IL3B1 exhibited typical NK-patterned cytotoxic activity against a panel of tumor cell targets. In addition, they showed significant cytotoxic activity against normal bone marrow cells, as well as various factor-dependent myelogenous progenitor cell lines, all of which were resistant to endogenous NK activity of the fresh spleen cells. These results indicated that at least a set of T3+ LGL with rearranged TCR genes could be directly differentiated from isolated hematopoietic progenitor cells in vitro. Results also suggested that such a prethymically differentiated subset of T-lineage lymphocytes, namely T3+ double-negative LGL, had particular cytotoxic activity in addition to conventional NK activity, which might well contribute to feedback regulation of hematopoiesis.


Asunto(s)
Linfocitos/inmunología , Animales , Antígenos de Superficie/análisis , Diferenciación Celular , Ensayo de Unidades Formadoras de Colonias , Factores Estimulantes de Colonias/farmacología , Citotoxicidad Inmunológica , Eritropoyetina/farmacología , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Interleucina-2/farmacología , Interleucina-3/farmacología , Leucemia Experimental/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Proteínas Recombinantes/farmacología , Células Tumorales Cultivadas
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