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1.
Scand J Rheumatol ; 48(3): 225-229, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30516404

RESUMO

OBJECTIVE: Dermatomyositis (DM) is an idiopathic inflammatory myopathy which often involves the lungs. DM is likely to be associated with aberrant T- and B-cell activation in the pathogenesis because of the proven effectiveness of T- and B-cell-targeted treatments. Assuming that the aberrant activation is reflected by biases in the lymphocyte subset repertoires, we aimed to elucidate these biases, especially in relation to clinical features of DM. METHOD: Based on the immunophenotyping standardized by the Human Immunology Project Consortium, untreated 13 DM patients, including seven patients with interstitial lung disease (ILD), and 18 age-matched healthy donors (HDs) were examined for proportions of peripheral blood lymphocyte subsets. Six DM patients were examined before and after successful induction of remission. RESULTS: Naïve CD4+ T cells and naïve B cells were more abundant, while there were fewer naïve CD8+ T cells, central memory CD8+ T cells, effector memory CD4+ T cells, Th1 cells, Tfh cells, and memory B cells in DM patients than in HDs. When the patients were subgrouped according to the presence of ILD, the lymphocyte subset repertoires in the patients with ILD contributed to the statistical differences in all the biased lymphocyte subset proportions. After treatment, transitional B cells vanished and there was an increase in memory B cells. CONCLUSION: The lymphocyte subset repertoires in the DM patients were biased, and were associated with the presence of ILD and disease activity of DM.


Assuntos
Dermatomiosite , Imunossupressores , Doenças Pulmonares Intersticiais , Subpopulações de Linfócitos/imunologia , Dermatomiosite/complicações , Dermatomiosite/diagnóstico , Dermatomiosite/tratamento farmacológico , Dermatomiosite/imunologia , Feminino , Humanos , Memória Imunológica/efeitos dos fármacos , Imunofenotipagem/métodos , Imunofenotipagem/estatística & dados numéricos , Imunossupressores/imunologia , Imunossupressores/uso terapêutico , Japão , Doenças Pulmonares Intersticiais/complicações , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/imunologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Gravidade do Paciente
3.
Lupus ; 25(5): 543-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26762472

RESUMO

Systemic lupus erythematosus-related hepatitis, known as lupus hepatitis, is a rare manifestation of systemic lupus erythematosus, and is usually subclinical with mild abnormalities of serum liver enzymes. While cases with clinically significant and refractory lupus hepatitis are uncommon, treatment options for lupus hepatitis are to be established. Here, we report the case of a 45-year-old man with progressive lupus hepatitis accompanied by autoimmune haemolytic anaemia. Lupus hepatitis of this patient was refractory to tacrolimus, azathioprine and cyclophosphamide, but was successfully treated by mycophenolate mofetil. Mycophenolate mofetil might be an effective therapeutic option for refractory lupus hepatitis.


Assuntos
Anemia Hemolítica Autoimune/tratamento farmacológico , Hepatite/tratamento farmacológico , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Ácido Micofenólico/uso terapêutico , Anemia Hemolítica Autoimune/diagnóstico , Anemia Hemolítica Autoimune/imunologia , Biópsia , Diagnóstico Diferencial , Resistência a Medicamentos , Substituição de Medicamentos , Hepatite/diagnóstico , Hepatite/imunologia , Hepatite Autoimune/diagnóstico , Humanos , Testes de Função Hepática , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Indução de Remissão , Resultado do Tratamento
4.
Lupus ; 22(3): 316-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23439471

RESUMO

A 37-year-old male with systemic lupus erythematosus (SLE) presented with high fever, subcutaneous indurations, anemia, thrombocytopenia, elevated liver enzymes and hyperferritinemia. Skin biopsy revealed hemophagocytic histiocytes in the adipose tissues. The patient was diagnosed with SLE with cytophagic histiocytic panniculitis (CHP). Treatment with high-dose glucocorticoids and cyclosporine A induced remission of SLE and CHP. CHP is generally a systemic disorder affecting subcutaneous adipose tissues with a high mortality rate. However, based on the present and previously reported cases, we believe that intensive immunosuppression can ameliorate CHP that occurs as a skin manifestation of SLE.


Assuntos
Ciclosporina/uso terapêutico , Glucocorticoides , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Paniculite/tratamento farmacológico , Adulto , Histiócitos/patologia , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/patologia , Masculino , Paniculite/complicações , Paniculite/patologia
5.
Dermatology ; 217(4): 374-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18827482

RESUMO

BACKGROUND: Although dermatomyositis (DM)-associated facial erythema was noted in the nasolabial folds of Japanese patients, DM-associated facial erythema other than heliotrope rash has drawn little attention in previous studies. OBJECTIVES: To characterize phenotypical features and frequencies of erythema, especially those in the seborrheic area of the head, in DM patients. METHODS: A retrospective study on skin manifestations in 33 DM patients followed up at our department during the past 15 years was conducted. RESULTS: Macular violaceous erythema (MVE) in the seborrheic area of the face was most frequent (67%). Patients with facial MVE had also MVE in the scalp significantly more frequently than those without facial MVE. The pathology of the facial MVE was dominated by DM-associated changes with slight changes compatible with seborrheic dermatitis (SD). CONCLUSIONS: Japanese DM patients had MVE frequently in the seborrheic area of the head. Its phenotypical features suggested that it might be triggered by SD.


Assuntos
Dermatite Seborreica/etiologia , Dermatomiosite/complicações , Eritema/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Dermatite Seborreica/diagnóstico , Dermatomiosite/diagnóstico , Eritema/diagnóstico , Dermatoses Faciais/etiologia , Feminino , Humanos , Japão , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Estudos Retrospectivos , Dermatoses do Couro Cabeludo/etiologia
6.
Neuroscience ; 152(1): 40-9, 2008 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-18242000

RESUMO

Despite extensive investigations into the mechanisms of aerobic respiration in mitochondria, the spontaneous metabolic activity of individual cells within a whole animal has not been observed in real time. Consequently, little is known about whether and how the level of mitochondrial energy metabolism is regulated in a cell during development of intact systems. Here we studied the dynamics of postsynaptic oxidative metabolism by monitoring the redox state of mitochondrial flavoproteins, an established indicator of energy metabolism, at the developing Drosophila neuromuscular junction. We detected transient and spatially synchronized flavoprotein autofluorescence signals in postsynaptic muscle cells. These signals were dependent on the energy substrates and coupled to changes in mitochondrial membrane potential and Ca2+ concentration. Notably, the rate of autofluorescence signals increased during synapse formation through contact with the motoneuronal axon. This rate was also influenced by the magnitude of synaptic inputs. Thus, presynaptic cells tightly regulate postsynaptic energy metabolism presumably to maintain an energetic balance during neuromuscular synaptogenesis. Our results suggest that flavoprotein autofluorescence imaging should allow us to begin assessing the progress of synapse formation from a metabolic perspective.


Assuntos
Metabolismo Energético/fisiologia , Mitocôndrias Musculares/metabolismo , Músculos/inervação , Músculos/metabolismo , Junção Neuromuscular/crescimento & desenvolvimento , Junção Neuromuscular/metabolismo , Animais , Respiração Celular/fisiologia , Drosophila , Flavoproteínas , Imuno-Histoquímica , Potencial da Membrana Mitocondrial/fisiologia , Neurônios Motores/metabolismo , Desenvolvimento Muscular/fisiologia , Fibras Musculares Esqueléticas/metabolismo
7.
Mod Rheumatol ; 13(1): 76-80, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24387121

RESUMO

Abstract Adult-onset Still's disease (AOSD) is a systemic inflammatory disorder of unknown origin. Acute respiratory distress syndrome (ARDS) is a rare complication of AOSD, with only nine cases having been reported in the literature. Here, we describe two cases of AOSD complicated with ARDS that were successfully treated with immunosuppressive therapy, including corticosteroids. Although ARDS is a life-threatening complication in AOSD, early commencement of high-dose corticosteroids and mechanical ventilation improve the prognosis.

8.
J Immunol ; 167(7): 4051-8, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11564826

RESUMO

Polymyositis (PM) involves destruction of striated muscles by autoaggressive CD8 T cells, which accumulate and secrete cytotoxic effector molecules in the affected muscles. Previous studies of peripheral T cell repertoires from normal individuals and patients with viral infections have shown that primed CD8 T cells, unlike CD4 T cells, are prone to expand clonally and persist as large populations in the peripheral blood. These facts made us assume that autoaggressive myocytotoxic CD8 T cells would expand clonally in the peripheral blood from patients with PM. By clonal analyses of peripheral T cells from patients and age-matched controls, we show here that clonal expansion of CD8 T cells was more frequent in patients. This was not significant in CD4 T cells. In analogy to virus-specific T cells, the expanded T cells persisted as large populations over time. Analysis of the muscle biopsy specimens revealed that some of the expanded clones were infiltrating in the affected muscles from the same patients. These results provide the first evidence that local autoimmune reaction directly elicits significant biases in peripheral T cell repertoire. The expanded cells, which should be candidate autoaggressive T cells, were readily isolated from the peripheral blood for analysis of expressed genes including perforin. Thus, our findings should give us an immediate clue to analysis of the pathogenic T cells in PM.


Assuntos
Ativação Linfocitária , Polimiosite/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Linfócitos T Citotóxicos/imunologia , Adulto , Sequência de Aminoácidos , Doenças Autoimunes/imunologia , Sangue/imunologia , Linfócitos T CD4-Positivos/imunologia , Células Clonais , Regiões Determinantes de Complementaridade/genética , Humanos , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Músculo Esquelético/imunologia , Perforina , Proteínas Citotóxicas Formadoras de Poros , RNA Mensageiro/biossíntese , Receptores de Antígenos de Linfócitos T alfa-beta/biossíntese
9.
Ryumachi ; 41(3): 653-8, 2001 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-11505515

RESUMO

We reported the case of a 39-year-old man with dermatomyositis (DM) complicated with subcutaneous emphysema and pneumomediastinum during steroid therapy. The patient had complained of muscle weakness, dyspnea and skin eruption on his anterior chest wall 6 months prior to admission. He was diagnosed as having DM on the basis of an elevation in myogenic enzymes, myogenic changes in electromyography, a skin biopsy and a muscle biopsy. Chest roentgenogram revealed interstitial pneumonia (IP) in the lower lobes of the lungs. The administration of prednisolone (60 mg/day) was initiated, which resulted in improvement of DM. Fifteen days after the initiation of the steroid therapy, the patient developed subcutaneous emphysema and pneumomediastinum. Additional administration of cyclosporin A (CsA) enabled us to rapidly taper the dose of prednisolone without aggravating the diseases. Several reports have shown that vasculitis might be involved in the pathogenesis of pneumomediastinum in DM patients. Infection and tissue fragility due to steroid therapy worsen the outcome of those patients. CsA therapy may improve the outcome through the anti-vasculitic- and steroid sparing-effects.


Assuntos
Ciclosporina/uso terapêutico , Dermatomiosite/tratamento farmacológico , Imunossupressores/uso terapêutico , Enfisema Mediastínico/tratamento farmacológico , Adulto , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/efeitos adversos , Dermatomiosite/complicações , Humanos , Masculino , Enfisema Mediastínico/etiologia , Prednisolona/administração & dosagem , Prednisolona/efeitos adversos , Resultado do Tratamento
10.
Int Immunol ; 13(6): 723-31, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11369699

RESUMO

Rheumatoid synovial fibroblasts (RSF) express cyclin-dependent kinase (CDK) inhibitors p16(INK4a) and p21(Cip1) when they are growth-inhibited in vitro. The induction of p16(INK4a) is characteristic of RSF and intra-articular p16(INK4a) gene therapy has been shown to suppress adjuvant arthritis (AA) of rats. The other inducible CDK inhibitor, p21(Cip1), has multiple functions depending on the cell type. They include inhibition of CDK as well as promotion of active CDK complex formation and induction of apoptosis. This study is to discern the biological effects of p21(Cip1) gene transfer into RSF and its therapeutic effects on AA. A recombinant adenovirus containing a human p21(Cip1) gene and control adenoviruses were prepared. RSF infected with these viruses were examined for their cell growth. Apoptotic cell death was evaluated by nuclear staining and DNA fragmentation analysis. In vivo gene therapy of rat AA was carried out by intra-articular injection of the viruses. Severity of the arthritis was clinically scored. The treated joints were examined histologically and proliferating cell nuclear antigens (PCNA) were detected immunohistochemically. The adenoviral p21(Cip1) gene transfer inhibited growth of RSF without inducing apoptosis. p21(Cip1) gene therapy suppressed AA clinically and histologically. The effects were comparable to p16(INK4a) gene therapy. PCNA expression was reduced in the p21(Cip1)-treated joints. The adenoviral gene transfer of p21(Cip1) ameliorated rat AA. The effect was attributable to inhibition of proliferation. Because p21(Cip1) is induced more easily by many chemicals than p16(INK4a), it also appears to be a feasible target in developing anti-rheumatic drugs.


Assuntos
Artrite Experimental/prevenção & controle , Quinases Ciclina-Dependentes/antagonistas & inibidores , Quinases Ciclina-Dependentes/genética , Ciclinas/administração & dosagem , Ciclinas/genética , Inibidores Enzimáticos/administração & dosagem , Articulações/enzimologia , Adenoviridae/genética , Animais , Apoptose/genética , Artrite Experimental/enzimologia , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/biossíntese , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos/administração & dosagem , Membro Posterior , Humanos , Injeções Intra-Articulares , Masculino , Ratos , Ratos Endogâmicos Lew , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia
12.
Nihon Rinsho Meneki Gakkai Kaishi ; 24(1): 21-8, 2001 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-11280897

RESUMO

A 20-year-old man was admitted to a hospital complaining a slight fever lasting for 3 months associated with a dull headache and weight loss. A tumor was found in the nasopharynx of which biopsy specimen revealed granulomas with Langhans' giant cells. He was given antituberculous agents without symptomatic improvement, and transferred to our hospital. Serum levels of soluble IL-2 receptor and lysozyme were increased, and a significant uptake was observed by Ga scintigraphy at the nasopharynx and bilateral hilar lymphnodes. Furthermore, spinal fluid contained increased number of mononuclear cells, and T2-weighted MRI scans showed an enhanced lesion at the pituitary stalk. The specimen of both TBLB and repeated biopsy of the nasopharyngeal tumor showed granulomas without caseous necrosis. Taken together with these findings, a diagnosis of sarcoidosis with CNS involvement was finally made, and he made a favorable progress by treatment with prednisolone. This is an unique case which emphasizes importance of differential diagnosis of nasopharyngeal tumors with neurological manifestations in the clinicalsetting of rheumatology.


Assuntos
Doenças do Sistema Nervoso Central/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Sarcoidose/diagnóstico , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Tuberculose/diagnóstico
13.
J Rheumatol ; 28(2): 240-4, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11246656

RESUMO

OBJECTIVE: Activated macrophages upregulate surface expression of common cytokine receptor gamma chains (gammac, CD132), triggering of which induces secretion of proinflammatory cytokines. Rheumatoid synovial tissues contain a number of macrophages that play a pathogenic role by secreting proinflammatory cytokines. We studied the expression of gammac in the rheumatoid synovial tissues. METHODS: Cryosections of synovial tissues from patients with active rheumatoid arthritis (RA) or with osteoarthritis (OA) were stained with an anti-gammac Mab. Single-cell suspensions from the rheumatoid synovial tissues were stained with the same antibody and an anti-CD14 monoclonal antibody (Mab) for 2-color flow cytometric analysis. A soluble form of gammac in synovial fluids collected from rheumatoid or OA joints was quantitated by ELISA. RESULTS: Rheumatoid synovial tissues, but not the OA tissues, expressed gammac at a high level. Flow cytometric analysis showed that gammac were expressed by virtually all CD 14 positive synovial cells in RA. Synovial fluid derived from the rheumatoid joints contained a high concentration of soluble gammac. CONCLUSION: Membrane bound and soluble forms of gammac are abundant in rheumatoid joints. They might play a complex role in the pathology of RA.


Assuntos
Artrite Reumatoide/metabolismo , Articulações/metabolismo , Receptores de Citocinas/metabolismo , Receptores de Interleucina-7/metabolismo , Artrite Reumatoide/patologia , Artrite Reumatoide/fisiopatologia , Humanos , Imuno-Histoquímica , Subunidade gama Comum de Receptores de Interleucina , Articulações/patologia , Articulações/fisiopatologia , Macrófagos/metabolismo , Macrófagos/patologia , Líquido Sinovial/metabolismo , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia
14.
J Immunol ; 165(12): 7246-52, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11120858

RESUMO

In rheumatoid synovial tissues, synovial fibroblasts are activated by proinflammatory cytokines and proliferate to develop hyperplastic pannus tissues, which irreversibly damage the affected joints. We recently reported that the cyclin-dependent kinase inhibitors p16(INK4a) and p21(Cip1) are not expressed in vivo in rheumatoid synovial fibroblasts, but are readily inducible in vitro. This observation was followed by the successful treatment of rat adjuvant arthritis by local p16(INK4a) gene transfer, showing that the inhibition of the cell cycle of the synovial cells ameliorates the arthritis. In this study, we show that another animal model of rheumatoid arthritis, murine collagen-induced arthritis, can be effectively treated by local gene transfer of p21(Cip1) as well as that of p16(INK4a). The anti-arthritic effects were observed even when the treatment was conducted after the arthritis had developed. Furthermore, the effects included suppression of the expression of proinflammatory cytokines such as IL-1ss, IL-6, and TNF-alpha. Our results demonstrate that the ectopic expression of cyclin-dependent kinase inhibitors not only prevents synovial overgrowth but also ameliorates the proinflammatory milieu in the affected joints. The induction of p21(Cip1) in rheumatoid synovial tissues by pharmacological agents may also be an effective strategy to treat rheumatoid arthritis.


Assuntos
Adenoviridae/genética , Artrite Experimental/prevenção & controle , Proteínas de Transporte/genética , Colágeno/imunologia , Quinases Ciclina-Dependentes/antagonistas & inibidores , Ciclinas/genética , Inibidores Enzimáticos/administração & dosagem , Técnicas de Transferência de Genes , Animais , Artrite Experimental/enzimologia , Artrite Experimental/imunologia , Artrite Experimental/patologia , Proteínas de Transporte/biossíntese , Proteínas de Transporte/uso terapêutico , Divisão Celular/genética , Divisão Celular/imunologia , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/biossíntese , Ciclinas/uso terapêutico , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Vetores Genéticos/administração & dosagem , Inibidores do Crescimento/genética , Inibidores do Crescimento/fisiologia , Humanos , Imunossupressores/administração & dosagem , Injeções Intra-Articulares , Interleucina-1/antagonistas & inibidores , Interleucina-1/biossíntese , Interleucina-6/antagonistas & inibidores , Interleucina-6/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos DBA , Membrana Sinovial/patologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese
16.
Mod Rheumatol ; 10(2): 78-82, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24383560

RESUMO

Abstract An accumulating body of evidence shows that gene therapy can be successfully used to treat animal models of arthritis. Based on this success, a clinical trial of gene therapy for rheumatoid arthritis has been initiated. We review the methods and genes used for the previous gene transfer experiments, including our own. Retroviral ex vivo gene transfer and adenoviral in vivo gene transfer were utilized most frequently. Most of the gene transfer strategies aimed at suppression of synovial inflammation, while our study attempted to convert a phenotype of synovial cells. Gene transfer could be used for part of the future therapy for RA. In basic research studies, gene transfer is of great help in defining new target molecules to treat arthritis.

18.
Nat Med ; 5(7): 760-7, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10395320

RESUMO

Synovial tissue affected by rheumatoid arthritis is characterized by proliferation, which leads to irreversible cartilage and bone destruction. Current and experimental treatments have been aimed mainly at correcting the underlying immune abnormalities, but these treatments often prove ineffective in preventing the invasive destruction. We studied the expression of cyclin-dependent kinase inhibitors in rheumatoid synovial cells as a means of suppressing synovial cell proliferation. Synovial cells derived from hypertrophic synovial tissue readily expressed p16INK4a when they were growth-inhibited. This was not seen in other fibroblasts, including those derived from normal and osteoarthritis-affected synovial tissues. In vivo adenoviral gene therapy with the p16INK4a gene efficiently inhibited the pathology in an animal model of rheumatoid arthritis. Thus, the induction of p16INK4a may provide a new approach to the effective treatment of rheumatoid arthritis.


Assuntos
Artrite Experimental/terapia , Artrite Reumatoide/terapia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Terapia Genética , Membrana Sinovial/fisiologia , Adenoviridae , Animais , Artrite Experimental/patologia , Divisão Celular , Células Cultivadas , Senescência Celular , Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , Cães , Vetores Genéticos , Humanos , Masculino , Ratos , Ratos Endogâmicos Lew , Proteínas Recombinantes de Fusão/biossíntese , Membrana Sinovial/patologia , Membrana Sinovial/fisiopatologia , beta-Galactosidase/biossíntese , beta-Galactosidase/genética
19.
Blood ; 93(11): 3713-22, 1999 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10339478

RESUMO

CrkL is a member of the Crk family of adapter proteins consisting mostly of SH2 and SH3 domains. CrkL is most abundantly expressed in hematopoietic cells and has been implicated in pathogenesis of chronic myelogenous leukemia. However, its function has not been precisely defined. Here, we show that overexpression of CrkL enhances the adhesion of hematopoietic 32D cells to fibronectin. The CrkL-induced increase in cell adhesion was blocked by antibodies against VLA-4 (alpha4beta1) and VLA-5 (alpha5beta1) but was observed without changes in surface expression levels of these integrins. Studies using CrkL mutants demonstrated that the SH2 domain is partially required for enhancing cell adhesion, whereas the C-terminal SH3 domain as well as the tyrosine phosphorylation site (Y207) is dispensable. In contrast, the N-terminal SH3 domain, involved in binding C3G and other signaling molecules, was showed to play a crucial role, because a mutant defective of this domain showed an inhibitory effect on the cell adhesion to fibronectin. Furthermore, overexpression of C3G also increased the adhesion of hematopoietic cells to fibronectin, whereas a C3G mutant lacking the guanine nucleotide exchange domain abrogated the CrkL-induced increase in cell adhesion. On the other hand, a dominant negative mutant of H-Ras or that of Raf-1 enhanced the basal and CrkL-induced cell adhesion and that of R-Ras modestly decreased the adhesion. Taken together, these results indicate that the CrkL-C3G complex activates VLA-4 and VLA-5 in hematopoietic cells, possibly by activating the small GTP binding proteins, including R-Ras, through the guanine nucleotide exchange activity of C3G.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Hematopoese , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Integrinas/fisiologia , Proteínas Nucleares/fisiologia , Proteínas/fisiologia , Receptores de Fibronectina/fisiologia , Receptores de Retorno de Linfócitos/fisiologia , Animais , Adesão Celular/fisiologia , Linhagem Celular , Fibronectinas , Regulação da Expressão Gênica/fisiologia , Fatores de Troca do Nucleotídeo Guanina , Humanos , Integrina alfa4beta1 , Camundongos , Transdução de Sinais/fisiologia , Fatores ras de Troca de Nucleotídeo Guanina , Domínios de Homologia de src
20.
Nihon Rinsho Meneki Gakkai Kaishi ; 22(5): 317-23, 1999 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-10616284

RESUMO

We experienced a case of Takayasu's arteritis (TA) with ulceritive colitis (UC) having the onset of carotodynia, not accompanied by ischemic symptoms. MRI findings of the neck demonstrated a thickening of the bilateral carotid artery walls. The patient was treated by prednisolone with a marked improvement in both clinical symptoms and MRI findings. The patient had a unique HLA haplotype reported to correlate with both TA and UC. Carotodynia is an early but pathognomonic symptom of TA and MRI is helpful for the early diagnosis of TA.


Assuntos
Colite Ulcerativa/complicações , Imageamento por Ressonância Magnética , Pescoço , Dor/etiologia , Arterite de Takayasu/complicações , Arterite de Takayasu/diagnóstico , Adulto , Feminino , Humanos
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