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1.
Clin Nutr ; 34(1): 79-85, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24530027

RESUMO

BACKGROUND & AIMS: Healthcare-associated infections [HAI] are common in elderly individuals and may be related to both nutritional deficiencies and immunosenescence. Here, we assessed whether overall malnutrition and/or specific nutrient deficiencies were associated with HAI via alterations in immune parameters. METHODS: Prospective observational cohort study in patients aged ≥ 70 years admitted to the geriatric rehabilitation unit of a teaching hospital in France between July 2006 and November 2008. Clinical and laboratory parameters reflecting nutritional status and immune function were collected at baseline. Flow cytometry was used to assess blood lymphocyte subsets including the naive CD4 T-cell count, naive and memory CD8 T-cell counts, effector CD8 T-cell count, and CD4/CD8 ratio. Patients were monitored for HAI for 3 months or until discharge from the geriatric unit or death. RESULTS: Of 252 consecutive in-patients aged ≥ 70 years [mean age, 85 ± 6.2 years], 181 [72%] met French National Authority for Health criteria for malnutrition and 97 [38%] experienced one or more HAI. Patients who subsequently experienced HAI had significantly lower baseline values for energy intake [odds ratio (OR), 0.76; 95% confidence interval (95%CI), 0.59-0.99], serum albumin [OR, 0.43; 95%CI, 0.32-0.58], serum zinc [OR, 0.77; 95%CI, 0.62-0.97], selenium [OR, 0.76; 95%CI, 0.61-0.95], and vitamin C [OR, 0.71; 95%CI, 0.54-0.93]. Associations linking these five variables to HAI were not significantly changed by adjusting for flow cytometry T-cell subset values. CONCLUSION: Our results suggest a direct effect of nutritional parameters on HAI rather than an indirect effect mediated by immune parameters.


Assuntos
Infecção Hospitalar/epidemiologia , Imunidade , Estado Nutricional , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Infecção Hospitalar/etiologia , Infecção Hospitalar/imunologia , Feminino , França , Geriatria , Hospitais de Ensino , Humanos , Contagem de Linfócitos , Masculino , Desnutrição/complicações , Avaliação Nutricional , Estudos Prospectivos
2.
Ann Dermatol Venereol ; 140(5): 367-72, 2013 May.
Artigo em Francês | MEDLINE | ID: mdl-23663709

RESUMO

BACKGROUND: Skin lesions are frequent in monoclonal cryoglobulinaemia and may be the first sign of B-cell lymphoma, especially multiple myeloma, Waldenström's macroglobulinaemia and B-cell chronic lymphocytic leukaemia. PATIENTS AND METHODS: A 74-year-old woman with no prior medical history presented with necrotic leg ulcer. Skin biopsy showed dermal angiomatosis with numerous PAS+ thromboses, associated with monoclonal intravascular deposits of IgM kappa, indicating monoclonal cryoglobulin, which was confirmed by laboratory tests. Subsequent blood immunophenotyping revealed an inconspicuous circulating monoclonal CD5(+) B-cell population and small B-cell clusters in the bone marrow, while the B-cell count was normal and no lymphadenopathy or splenomegaly were present. Overall, these findings indicated a small B-cell lymphoma, classed as non-MALT marginal zone lymphoma on the WHO classification, at a very early stage of development. The patient was first treated by cyclophosphamide and oral steroids without success. Subsequent administration of six cycles of rituximab, cyclophosphamide, vincristine and prednisone (RCVP) led to remission of her leg ulcer, cryoglobulinaemia and lymphoma. CONCLUSION: Skin biopsies of necrotic ulcers should undergo routine screening for intravascular deposits of type 1 cryoglobulin. Leg ulcers due to monoclonal cryoglobulinaemia may reveal incipient marginal zone B-cell lymphoma at the stage of circulating monoclonal lymphocytosis.


Assuntos
Crioglobulinemia/etiologia , Úlcera da Perna/etiologia , Linfoma de Zona Marginal Tipo Células B/complicações , Corticosteroides/administração & dosagem , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfócitos B/química , Linfócitos B/patologia , Medula Óssea/patologia , Crioglobulinas/análise , Ciclofosfamida/administração & dosagem , Feminino , Humanos , Imunoglobulina M/análise , Cadeias kappa de Imunoglobulina/análise , Imunofenotipagem , Úlcera da Perna/patologia , Contagem de Linfócitos , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Prednisona/administração & dosagem , Indução de Remissão , Rituximab , Vincristina/administração & dosagem
3.
Ann Oncol ; 23(5): 1274-1279, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21965472

RESUMO

BACKGROUND: Central nervous system (CNS) relapse is an uncommon but dramatic complication of diffuse large B-cell lymphoma (DLBCL). Several studies have demonstrated the superiority of cerebrospinal fluid (CSF) flow cytometry (FCM), as compared with conventional cytology (CC), in detecting occult leptomeningeal disease. The clinical relevance of a positive FCM still has to be clarified. PATIENTS AND METHODS: We analyzed CSF from 114 DLBCL patients at diagnosis (n = 95) or at relapse (n = 19) by FCM and CC. Most patients received meningeal prophylaxis. FCM results did not influence treatment strategies. RESULTS: Fourteen samples were FCM+, versus one CC+ (also FCM+). Within all patients without neurological symptoms (n = 101), four (4%) relapsed in the CNS, with a median time to relapse of 5.2 months. Only one-fourth (25%) was FCM+ before relapse. More than one extranodal disease site and elevated lactate dehydrogenase levels were associated with an increased risk of CNS relapse. CONCLUSIONS: FCM gives far more positive results than CC. However, a positive FCM result did not translate into a significant increase in CNS relapse rate in this histologically uniform population receiving CNS prophylaxis.


Assuntos
Neoplasias do Sistema Nervoso Central/diagnóstico , Citometria de Fluxo/métodos , Imunofenotipagem/métodos , Linfoma Difuso de Grandes Células B/líquido cefalorraquidiano , Linfoma Difuso de Grandes Células B/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso Central/secundário , Citodiagnóstico/métodos , Feminino , Humanos , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Recidiva , Adulto Jovem
4.
Immun Ageing ; 8: 8, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21961997

RESUMO

BACKGROUND: Nosocomial infections are extremely common in the elderly and may be related to ageing of the immune system. The Immune Risk Phenotype (IRP), which predicts shorter survival in elderly patients, has not been evaluated as a possible risk factor for nosocomial infection. Our aim was to assess the prevalence of nosocomial infections in elderly in-patients and to investigate potential relationships between nosocomial infections and the immunophenotype, including IRP parameters. RESULTS: We included 252 consecutive in-patients aged 70 years or over (mean age, 85 ± 6.2 years), between 2006 and 2008. Among them, 97 experienced nosocomial infections, yielding a prevalence rate of 38.5% (95% confidence interval, 32.5-44.5). The main infection sites were the respiratory tract (21%) and urinary tract (17.1%) When we compared immunological parameters including cell counts determined by flow cytometry in the groups with and without nosocomial infections, we found that the group with nosocomial infections had significantly lower values for the CD4/CD8 ratio and naive CD8 and CD4 T-cell counts and higher counts of memory CD8 T-cells with a significant increase in CD28-negative CD8-T cells. Neither cytomegalovirus status (positive in 193/246 patients) nor presence of the IRP was associated with nosocomial infections. However, nosocomial pneumonia was significantly more common among IRP-positive patients than IRP-negative patients (17/60 versus 28/180; p = 0.036). CONCLUSION: Immunological parameters that are easy to determine in everyday practice and known to be associated with immune system ageing and shorter survival in the elderly are also associated with an elevated risk of nosocomial pneumonia in the relatively short term.

5.
Haematologica ; 92(12): e132-5, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18055978

RESUMO

Delayed hemolytic transfusion reaction (DHTR), a life-threatening transfusion complication in sickle cell disease (SCD), is characterized by a marked hemoglobin drop with destruction of both transfused and autologous red blood cells (RBCs) and exacerbation of SCD symptoms. One mechanism of RBCs destruction is auto-antibody production secondary to transfusion. As rituximab specifically targets circulating B cells, we thought that it could be beneficial in preventing this immune-mediated transfusion complication. We report the case of a SCD patient who previously experienced DHTR with auto-antibodies and who needed a new transfusion. DHTR recurrence was successfully prevented by rituximab administration prior transfusion, supporting the safe use of rituximab to prevent DHTR in SCD patients as a second line approach when other measures failed.


Assuntos
Anemia Hemolítica Autoimune/terapia , Anemia Falciforme/terapia , Anticorpos Monoclonais/administração & dosagem , Transfusão de Eritrócitos , Hemólise/efeitos dos fármacos , Adulto , Anemia Hemolítica Autoimune/sangue , Anemia Hemolítica Autoimune/etiologia , Anemia Hemolítica Autoimune/imunologia , Anemia Falciforme/sangue , Anemia Falciforme/complicações , Anemia Falciforme/imunologia , Anticorpos Monoclonais Murinos , Autoanticorpos/sangue , Linfócitos B/imunologia , Linfócitos B/metabolismo , Transfusão de Eritrócitos/efeitos adversos , Eritrócitos/imunologia , Eritrócitos/metabolismo , Hemólise/imunologia , Humanos , Fatores Imunológicos , Rituximab
6.
Ann Oncol ; 18(7): 1209-15, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17496307

RESUMO

BACKGROUND: Lymphocytopenia is a prognostic factor in Hodgkin's disease. In diffuse large B-cell lymphoma (DLBCL), data are much less established, in spite of numerous reports on immune system-lymphoma interactions. This study addresses the prognostic value of blood lymphocyte subsets at diagnosis in DLBCL. PATIENTS AND METHODS: Absolute values of blood lymphocyte subsets and monocytes were prospectively determined by flow cytometry in 140 patients with 2 or 3 adverse age-adjusted International Prognostic Index (aaIPI) factors included in a Groupe d'Etude des Lymphomes de l'Adulte protocol (LNH98B3). Absolute cell counts at diagnosis and aaIPI were evaluated with regard to clinical outcome. RESULTS: Low median cell counts of 337, 211, and 104/mul were evidenced for the CD4+, CD8+ T, and natural killer (NK) cells, respectively. In univariate analysis, only NK cell count [odds ratio (OR) = 1.81 (1.27, 2.57), P = 0.001] and aaIPI [OR = 2.29 (0.95, 5.45), P = 0.06] were associated with induction treatment response. Low NK cell count [Hazard ratio (HR) = 1.27 (1.06, 1.52), P = 0.01] and aaIPI 3 [HR = 1.95 (1.20, 3.16), P = 0.01] were also associated with a shorter event free survival (EFS). In multivariate analysis, NK cell count was associated with response [OR = 1.77 (1.24, 2.54), P = 0.002] and EFS [HR = 1.25 (1.04, 1.50) P = 0.02] independently of aaIPI. CONCLUSIONS: This study shows an association between circulating NK cell number and clinical outcome in DLBCL, possibly important in the context of the broadening use of rituximab, a likely NK-dependent therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Células Matadoras Naturais/citologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/imunologia , Linfopenia , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfócitos B/citologia , Bleomicina/administração & dosagem , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Contagem de Células , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Monócitos/citologia , Transplante de Células-Tronco de Sangue Periférico , Rituximab , Resultado do Tratamento , Vincristina/administração & dosagem
8.
J Neuroimmunol ; 134(1-2): 118-27, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12507779

RESUMO

Infiltration of activated lymphocytes and monocytes is a key phenomenon in the pathogenesis of Guillain-Barré syndrome (GBS) and experimental autoimmune neuritis (EAN). To investigate the role of chemokines, we determined the blood and nerve tissue expression of monocyte chemoattractant protein 1 (MCP-1), a major chemoattractant of monocytes and activated lymphocytes, and its receptor CCR2 in GBS and EAN. MCP-1 circulating levels (ng/ml) in GBS were increased at the time of progression, peaked at the time of plateau and normalized with recovery. MCP-1 circulating levels were the highest in the most disabled patients. The number of circulating CCR2 positive cells was lower in patients with GBS than in healthy subjects (p<0.004). In GBS, MCP-1 expression was observed in epineurial and endoneurial vessels, on infiltrating cells, Schwann cells and in the endoneurial extracellular matrix. Some CCR2 positive cells were observed in nerve biopsies of GBS patients. In EAN, a slight positivity for MCP-1 was observed in the sciatic nerve. There was no circulating CCR2 positive cells. However, at the time of plateau, a conspicuous infiltration of CCR2 positive cells was observed in the sciatic nerve that was no longer observed at the time of recovery. These results suggest that MCP-1 and CCR2 may participate to the recruitment of circulating mononuclear cells in nerve tissue in EAN and GBS.


Assuntos
Quimiocina CCL2/imunologia , Quimiotaxia de Leucócito/imunologia , Síndrome de Guillain-Barré/imunologia , Neurite Autoimune Experimental/imunologia , Nervos Periféricos/imunologia , Receptores de Quimiocinas/imunologia , Animais , Contagem de Células , Quimiocina CCL2/sangue , Modelos Animais de Doenças , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Endotélio Vascular/metabolismo , Feminino , Síndrome de Guillain-Barré/sangue , Síndrome de Guillain-Barré/patologia , Humanos , Imuno-Histoquímica , Linfócitos/citologia , Linfócitos/imunologia , Linfócitos/metabolismo , Monócitos/citologia , Monócitos/imunologia , Monócitos/metabolismo , Neurite Autoimune Experimental/sangue , Neurite Autoimune Experimental/patologia , Nervos Periféricos/irrigação sanguínea , Nervos Periféricos/patologia , Nervo Fibular/irrigação sanguínea , Nervo Fibular/imunologia , Nervo Fibular/patologia , Ratos , Ratos Endogâmicos Lew , Receptores CCR2 , Receptores de Quimiocinas/sangue , Nervo Isquiático/irrigação sanguínea , Nervo Isquiático/imunologia , Nervo Isquiático/patologia
9.
J Neuroimmunol ; 122(1-2): 100-5, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11777548

RESUMO

T-cell clones of unknown significance (TCUS), assessed by monoclonal or oligoclonal T-cell patterns in PCR-DGGE, were detected in blood of 7/9 patients with anti-Hu syndrome. Clonal patterns were also detected in 2/2 neoplastic lymph nodes, and in 2/2 inflamed dorsal root ganglia from three patients. Only some T-cell clones found in target tissues were also detected in blood or non-target tissues, and likely corresponded to TCUS. In one patient, an identical T-cell clone was found in both neoplastic lymph node tissue and dorsal root ganglia, but not in blood. Dorsal root-infiltrating lymphocytes were cytotoxic CD8(+) TIA-1(+) T-cells. They were often found in close contact to sensory neurons, most of which expressed MHC-1. Taken together, these data support a direct effector role of cytotoxic CD8(+) T-cells, the same clones being likely operative in sensory neuron damage and immune-mediated tumor growth control.


Assuntos
Proteínas do Tecido Nervoso/imunologia , Polineuropatia Paraneoplásica/imunologia , Proteínas de Ligação a RNA/imunologia , Linfócitos T/imunologia , Linfócitos T/patologia , Adulto , Idoso , Células Clonais , Proteínas ELAV , Feminino , Gânglios Espinais/patologia , Rearranjo Gênico do Linfócito T/imunologia , Humanos , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Neurite (Inflamação)/imunologia , Polineuropatia Paraneoplásica/patologia
10.
Neurology ; 57(9): 1704-6, 2001 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-11706116

RESUMO

The adhesion capacities, transmigration capacities, and integrin expression of lymphocytes from patients with Guillain-Barré syndrome incubated with interferon-beta were studied. Interferon-beta induced a dose-dependent inhibition of lymphocyte adhesion to recombinant vascular adhesion molecule-1 (p < 0.0001) and recombinant intercellular adhesion molecule-1 (rICAM-1) (p < 0.01) without modulation of very late activation molecule-4 and lymphocyte function-associated antigen-1 expressions and a dose-dependent decrease of lymphocyte transmigration across fibronectin (p < 0.0001). Inhibition of adhesion to rICAM-1 was similar after long (18 hours) or short (5 minutes) incubation time. These results support the potential therapeutic benefit of interferon-beta in Guillain-Barré syndrome.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Síndrome de Guillain-Barré/tratamento farmacológico , Síndrome de Guillain-Barré/imunologia , Interferon beta/administração & dosagem , Linfócitos/citologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/imunologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Relação Dose-Resposta a Droga , Citometria de Fluxo , Humanos , Técnicas In Vitro , Integrina alfa4beta1 , Integrinas/análise , Antígeno-1 Associado à Função Linfocitária/análise , Linfócitos/química , Receptores de Retorno de Linfócitos/análise , Molécula 1 de Adesão de Célula Vascular/farmacologia
11.
J Neuroimmunol ; 114(1-2): 188-96, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11240031

RESUMO

Intraneural inflammation, that reflects emigration of immune cells from blood to nerve tissue, is a critical event in Guillain-Barré syndrome pathogenesis. To investigate the adhesion and transmigration phases of leukodiapedesis, we determined in a series of patients with GBS: (1) circulating levels of soluble forms of adhesion molecules (sICAM-1 and sVCAM-1); (2) attachment capacities of circulating lymphocytes to rICAM-1 and rVCAM-1; (3) fibronectin-penetrating capacities of circulating lymphocytes; and (4) lymphocyte intracellular concentrations of MMP-9 at the different phases of GBS and in healthy controls. Circulating levels of sVCAM-1 and sICAM-1 were above normal values at the time of progression, markedly increased at the time of plateau (sVCAM-1: P<0.03; sICAM-1: P<0.02), and tended to normalize during recovery. The percentage of cells with attachment capacities to rVCAM-1 and to rICAM-1 decreased from progression to recovery by 30 and 31%, respectively (P<0.02). The number of circulating lymphocytes with fibronectin penetrating capacities was lower than controls at the time of progression (P<0.01), then progressively increased to reach values higher than controls at the time of late recovery (P<0.02). Cellular concentrations of MMP-9 in circulating lymphocytes paralleled their fibronectin penetrating capacities. These results suggest early emigration of lymphocytes into nerve, followed by shedding of adhesion molecules from endothelium, and late decrease of lymphocyte adhesion capacities. Plateau and recovery are associated with accumulation in the vascular compartment of still proteolytically active lymphocytes that can no longer adhere to endothelial cells. Modulation of the adhesion step of leukodiapedesis may be crucially involved in the switch from progression to plateau of GBS.


Assuntos
Movimento Celular/imunologia , Síndrome de Guillain-Barré/imunologia , Linfócitos/imunologia , Recuperação de Função Fisiológica/imunologia , Adesão Celular/imunologia , Seguimentos , Humanos , Molécula 1 de Adesão Intercelular/sangue , Linfócitos/citologia , Linfócitos/enzimologia , Metaloproteinase 9 da Matriz/metabolismo , Solubilidade , Molécula 1 de Adesão de Célula Vascular/sangue
12.
J Immunol Methods ; 241(1-2): 69-81, 2000 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-10915850

RESUMO

The therapeutic use of dendritic cells (DC) in antigen-specific anti-tumor vaccines, requires sufficient numbers of functional DC, the preparation of which should comply with the code of Good Manufacturing Practice. In addition, the expression of tumor specific antigen should be possible in these DC. As a preclinical step, the method reported here was developed in healthy volunteers. Monocytes (Mo) were isolated by leukapheresis from 12 donors, purified by elutriation and then cultured for 6 days in sealed bags in AIM-V serum free medium with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-13 (IL-13). Between 6x10(8) and 1x10(9) immature DC (iDC) could be differentiated from one leukapheresis. Cells displayed a characteristic iDC phenotype (CD1a(+), CD14(-), CD80(+), CD86(+), HLA DR(+), CD83(-)), and had potent allogeneic and antigen dependent autologous T cell-stimulatory capacity. Moreover, iDC could be further differentiated into mature DC by CD40 ligation as assessed by CD83 expression and the upregulation of HLA-DR and costimulatory molecules. After infection with a recombinant adenovirus encoding for beta-galactosidase (betaGal), 50% to 80% of iDC expressed betaGal without toxicity. Adenovirus infection increased the expression of both costimulatory molecules and CD83, and also increased allogeneic stimulatory capacity. Thus, the method developed here allows us to use large numbers of functional iDC as will be required for therapeutic uses in man. These DC can express a transgenic protein.


Assuntos
Vacinas Anticâncer , Técnicas de Cultura/métodos , Células Dendríticas/citologia , Células Dendríticas/imunologia , Transgenes , Adenoviridae , Apresentação de Antígeno , Antígenos CD , Diferenciação Celular , Separação Celular/métodos , Células Cultivadas , Técnicas de Transferência de Genes , Vetores Genéticos , Antígenos HLA-DR/biossíntese , Humanos , Imunoglobulinas/biossíntese , Leucaférese , Teste de Cultura Mista de Linfócitos , Glicoproteínas de Membrana/biossíntese , Proteínas Recombinantes/imunologia , Linfócitos T/imunologia , beta-Galactosidase/genética , beta-Galactosidase/imunologia , Antígeno CD83
13.
Exp Cell Res ; 258(2): 237-44, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10896774

RESUMO

The urokinase-type plasminogen activator system is a proteolytic system involved in tissue remodeling and cell migration. At the cell surface, receptor (uPAR)-bound urokinase (uPA) binds its inhibitor PAI-1, localized in the matrix, and the complex is internalized by endocytic receptors, such as the low-density lipoprotein receptor-related protein (LRP). We previously proposed a nonproteolytic role for the uPA system in human myogenic cell differentiation in vitro, i.e., cell fusion, and showed that myogenic cells can use PAI-1 as an adhesion matrix molecule. The aim of this study was to define the role of the uPA system in myogenic cell migration that is necessary for fusion. Using a two-dimensional motility assay and microcinematography, we showed that any interference with the [uPAR:uPA:PAI-1] complex formation, and interference with LRP binding to this complex, markedly decreased myogenic cell motility. This phenomenon was reversible and independent of plasmin activity. Inhibition of cell motility was associated with suppression of both filopodia and membrane ruffling activity. [uPAR:uPA:PAI-1:LRP] complex formation involves high-affinity molecular interactions and results in quick internalization of the complex. It is likely that this complex supports the membrane ruffling activity involved in the guidance of the migrating cell toward appropriate sites for attachment.


Assuntos
Movimento Celular/fisiologia , Músculos/citologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Imunológicos/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Diferenciação Celular , Células Cultivadas , Humanos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Receptores de Ativador de Plasminogênio Tipo Uroquinase
14.
Cell Death Differ ; 6(10): 1012-21, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10556979

RESUMO

We evaluated the expression of IL-1 system by normal human myogenic cells during in vitro myogenesis and the effect of exogenous IL-1beta. Expression of IL-1alpha and beta, IL-1 receptor antagonist (IL-1Ra), IL-1RI and II, IL-1R accessory protein (IL-1RAcP) and IL-1beta converting enzyme (ICE) was studied by immunocytochemistry, immunoblotting, ELISA and RT - PCR. Cell proliferation was evaluated by [3H]thymidine incorporation, cell fusion by flow cytometry and cell death by in situ end-labelling. Human normal myogenic cells constitutively produced IL-1beta and ICE, with a maximum expression at time of cell fusion. IL-1Rs and IL-1RAcP expression reached a peak at time of commitment to fusion. Myogenic cells produced small amounts of IL-1Ra at latest stages of culture, and only the intracellular isoform. Exposure of cultures to exogenous IL-1beta (1-5 ng/ml) induced myogenic cell apoptosis, without effect on cell proliferation or fusion. IL-1beta-induced cell death was associated with morphological changes including spreading appearance of cells and alteration of cell alignment. We conclude that (1) human myogenic cells constitutively produce IL-1beta; (2) IL-1 system components are differentially expressed during in vitro myogenesis; (3) IL-1 system participates to the coordinated regulation of cell density during normal myogenesis, which could serve to control the muscle mass in vivo.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Caspases , Cisteína Endopeptidases , Interleucina-1/antagonistas & inibidores , Interleucina-1/biossíntese , Interleucina-1/farmacologia , Fibras Musculares Esqueléticas/citologia , Proteínas , Caspase 7 , Técnicas de Cultura de Células , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Proteína Acessória do Receptor de Interleucina-1 , Biossíntese de Proteínas , Sialoglicoproteínas/biossíntese , Sialoglicoproteínas/farmacologia
15.
Transfusion ; 39(8): 873-9, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10504124

RESUMO

BACKGROUND: CD36 is expressed on several cell lineages. About 5 to 10 percent of Asians lack platelet membrane CD36 (pCD36), but the frequency of pCD36 deficiency in other ethnic groups is not known. Persons who are pCD36-negative are apparently healthy but can develop CD36 isoimmunization. STUDY DESIGN AND METHODS: The pCD36 phenotype was studied in 1885 subjects belonging either to a group of 1127 healthy French blood donors (almost all of whom were white Europeans) or to a group of 758 patients of known ethnic origin. RESULTS: No pCD36-negative persons were found among the blood donors. Only 1 of the 301 white European patients was pCD36-negative. In contrast, 16 of the 206 sub-Saharan Africans was pCD36-negative, a proportion higher than that among that black Caribbeans (1/148, p<0.01). The frequency of pCD36-negative patients was similar in blacks with and without sickle cell disease. Monocyte CD36 (mCD36) expression was studied in 15 of 22 pCD36-negative individuals: it was <10 percent in 7 subjects (type I deficiency) and between 12 and 100 percent in 8 others (type II deficiency). Thirteen pCD36-negative individuals had risk factors for immunization, and 4 had anti-CD36. Some had a history resembling posttransfusion purpura (n = 2), platelet transfusion refractoriness (n = 1), and recurrent miscarriage (n = 1). No correlation was found between immunization and the amount of mCD36. Anti-CD36 from an immunized type II-deficient woman reacted with monocytes from normal controls but not with monocytes from type I- or type II-deficient individuals, and thus it is postulated that mCD36 could be structurally different in normal and type II CD36-deficient individuals. CONCLUSION: CD36 deficiency is frequent in sub-Saharan Africans; development of anti-CD36 can lead to serious complications in multiply transfused patients, such as those with sicke cell disease.


Assuntos
Plaquetas/imunologia , Adulto , África Subsaariana , Reações Antígeno-Anticorpo , Ásia , Doadores de Sangue , Plaquetas/citologia , Antígenos CD36/sangue , Antígenos CD36/genética , Antígenos CD36/fisiologia , Linhagem da Célula , Criança , Feminino , Humanos , Imunização , Isoanticorpos/sangue , Isoanticorpos/imunologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Fenótipo , Gravidez , Traço Falciforme/etnologia
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