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M Takeno

Publications and source records attributed to M Takeno.

At least 19 recordsLinked to original sources
PubMed2005

Excessive expression of Txk, a member of the Tec family of tyrosine kinases, contributes to excessive Th1 cytokine production by T lymphocytes in patients with Behcet's disease.

Excessive Th1 cell function is importantly involved in the pathogenesis of Behcet's disease (BD). We previously found that Txk, a member of the Tec family of tyrosine kinases, acts as a Th1 cell specific transcription factor. To investigate immune aberration in the pathogenesis of BD, we studied the expression of Txk and Th1 cytokines in peripheral blood lymphocytes (PBL) and skin lesions in patients with BD. Cytokine production by the lymphocytes was assessed using ELISA. PBL produced excessive Th1 associated cytokines including IFN-gamma and IL-12 spontaneously and in response to exogenous HSP60-derived peptide stimulation, which was shown to induce proliferation of PBL, in patients with BD. Circulating CD4+ T cells expressed excessive Txk protein. A majority of cells infiltrating into skin lesions expressed IFN-gamma in the BD specimens. IL-12 and IL-18 were also expressed in the mononuclear cell aggregates. Lymphocytes accumulating in the skin lesion expressed higher levels of Txk as compared with atopic dermatitis lesions, a typical Th2 disease. IFN-gamma, IL-18 and Il-12 were detected in the BD skin lesions, which may induce preferential development of Th1 cells in patients with BD. The mononuclear cell aggregates contained Txk expressing cells in such skin lesions. Collectively, Txk expressing Th1 cells and the Th1 associated cytokines may play a critical role in the development of skin lesions in BD.

Adult↗
PubMed2004

Th1-dominant shift of T cell cytokine production, and subsequent reduction of serum immunoglobulin E response by administration in vivo of plasmid expressing Txk/Rlk, a member of Tec family tyrosine kinases, in a mouse model.

BACKGROUND: Th1 and Th2 cells, resulting from antigenic stimulation in the presence of IL-12 and IL-4, respectively, are implicated in the pathology of various diseases including allergic and autoimmune diseases. Txk/Rlk is a member of Tec family tyrosine kinases. We reported that Txk acts as a Th1-specific transcription factor in the T lymphocytes. OBJECTIVE: In this study we have asked whether administration of txk expression plasmid brings about a Th1/Th2 shift in vivo of the mice, and subsequent reduction of circulating IgE. METHODS: Mice were administered a txk expression plasmid with hemagglutinating virus of Japan (HVJ) envelope vector. Txk expressions in spleen cells were assessed by immunoblotting and immunocytochemical staining. Cytokine productions by the spleen cells and serum Ig concentrations were studied by ELISA. RESULTS: Administration of a txk expression plasmid with HVJ vector induced expression of Txk in the spleen cells. The spleen cells showed enhanced Th1-specific cytokine production; spleen cells from the txk administered mice produced more IFN-gamma as compared with those from control plasmid-administered mice in an antigen-specific manner. IL-2 and IL-4 secretions of the spleen cells were comparable between the two mouse groups. Txk administration did not reduce serum IgG concentration. It markedly reduced total IgE level and an IgG1/IgG2a ratio, reflection of Th1/Th2 balance, in sera. Furthermore, txk administration reduced ovalbumin (OVA)-specific IgE levels in sera of the OVA sensitized mice. CONCLUSION: Thus, Txk enhances IFN-gamma secretion and thus modulates Th1/Th2 cytokine balance, leading to reduction of serum IgE.

Animals↗
PubMed2004

Chemical induction of HO-1 suppresses lupus nephritis by reducing local iNOS expression and synthesis of anti-dsDNA antibody.

There is accumulating evidence that haem oxygenase (HO)-1 plays a protective role in various disorders. The beneficial efficacy of HO-1 induction therapy has been shown in renal diseases such as glomerulonephritis, interstitial nephritis and drug induced nephrotoxicity. However, involvement of HO-1 in the development of autoimmune renal diseases remains uncertain. To assess the clinical efficacy of HO-1 induction therapy for lupus glomerulonephritis, MRL/lpr mice were intraperitoneally injected with 100 micromol/kg hemin, a potent HO-1 inducer, or PBS as controls, once a week from 6 weeks of age to 21-24 weeks-old. We found that treatment with hemin led to a significant reduction of proteinuria and remarkable amelioration of glomerular lesions accompanied by decreased immune depositions. In addition, the circulating IgG anti-double-stranded DNA antibody level was significantly decreased in hemin treated mice when compared with controls. A single intraperitoneal injection with hemin resulted in reduction of inducible nitric oxide synthase expression in the kidney and spleen, and serum interferon-gamma level. Our results suggest that HO-1 induction therapy ameliorates lupus nephritis by suppressing nitric oxide (NO) dependent inflammatory responses and attenuating production of pathogenic autoantibodies.

Animals↗
PubMed2000

Novel approaches to Behçet's disease.

Behçet's disease is a systemic inflammatory disorder. The patients have repeated exacerbations and remissions of the symptoms. This disease may produce a wide variety of symptoms. In mild cases, mucocutaneous lesions are only the symptoms during the whole clinical course, whereas ocular lesions, which occur in about 70% of the patients, can cause blindness. Involvement of the gastrointestinal tract, CNS and large vessels is less frequent, but sometimes life-threatening. Colchicine, NSAIDs, corticosteroids and immunosuppressants are employed for the treatment of Behçet's disease with therapies tailored to individual patients depending on clinical manifestations. Cyclosporin A is the most effective drug for ocular lesions at the present, but its neurotoxicity, which occurs in 20-30% of patients receiving cyclosporin A, restricts usage of the agent. Many patients are still suffering from a severe form of uveitis and serious neurological symptoms, which are resistant to any conventional therapies. New drugs have been investigated for Behçet's disease. IFN-alpha therapy has shown significant efficacy for common symptoms including ocular lesions without any serious adverse effects. Thalidomide and its analogues also appear to be applicable to this disease. Monoclonal antibody to TNF-alpha is now in clinical trials. These novel therapeutic approaches may provide much needed treatment options for patients with Behçet's disease.

Antiviral Agents↗
PubMed2000

Current therapy in Behcet's disease.

Behçet's disease is an inflammatory disorder of unknown cause. There is often involvement of the gastrointestinal system, the central nervous system and large vessels, which can be life-threatening. As well, ocular lesions can cause blindness. Mucocutaneous symptoms are self-limiting but more frequent. Almost all the patients have recurrent oral aphthous ulcers, and more than 70% of the patients have genital ulcers and skin symptoms, which include erythema nodosum, pseudofolliculitis, papulopustular lesions, acneiform nodules and a positive pathergy test. The pathergy test is felt to reflect cutaneous hypersensitivity. In general, topical treatment using corticosteroids is satisfactory for these mucocutaneous lesions unless eye and vital organs are involved.

Adrenal Cortex Hormones↗
PubMed2000

[Behçet's disease].

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Anti-Inflammatory Agents↗
PubMed1999

Behçet's disease.

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Anti-Inflammatory Agents↗
PubMed1999

Txk, a nonreceptor tyrosine kinase of the Tec family, is expressed in T helper type 1 cells and regulates interferon gamma production in human T lymphocytes.

Differentiation of human T cells into T helper (Th)1 and Th2 cells is vital for the development of cell-mediated and humoral immunity, respectively. However, the precise mechanism responsible for the Th1 cell differentiation is not fully clarified. We have studied the expression and function of Txk, a member of the Tec family of nonreceptor tyrosine kinases. We found that Txk expression is restricted to Th1/Th0 cells with IFN-gamma producing potential. Txk transfection of Jurkat T cells resulted in a several-fold increase of IFN-gamma mRNA expression and protein production; interleukin (IL)-2 and IL-4 production were unaffected. Antisense oligodeoxynucleotide of Txk specifically inhibited IFN-gamma production of normal peripheral blood lymphocytes, antigen-specific Th1 clones, and Th0 clones; IL-2 and IL-4 production by the T cells was unaffected. Txk cotransfection led to the enhanced luciferase activity of plasmid (p)IFN-gamma promoter/enhancer (pIFN-gamma[-538])-luciferase-transfected Jurkat cells upon mitogen activation. Txk transfection did not affect IL-2 and IL-4 promoter activities. Thus, Txk specifically upregulates IFN-gamma gene transcription. In fact, Txk translocated from cytoplasm into nuclei upon activation and transfection with a mutant Txk expression plasmid that lacked a nuclear localization signal sequence did not enhance IFN-gamma production by the cells, indicating that nuclear localization of Txk is obligatory for the enhanced IFN-gamma production. In addition, IL-12 treatment of peripheral blood CD4(+) T cells enhanced the Txk expression, whereas IL-4 treatment completely inhibited it. These results indicate that Txk expression is intimately associated with development of Th1/Th0 cells and is significantly involved in the IFN-gamma production by the cells through Th1 cell-specific positive transcriptional regulation of the IFN-gamma gene.

Cell Differentiation↗
PubMed1999

Factors associated with the development of neonatal tolerance after the administration of a plasmid DNA vaccine.

A plasmid DNA vaccine encoding the circumsporozoite protein of malaria (pCSP) induces tolerance rather than immunity when administered to newborn mice. We find that this tolerance persists for >1 yr after neonatal pCSP administration and interferes with the induction of protective immunity in animals challenged with live sporozoites. Susceptibility to tolerance induction wanes rapidly with age, disappearing within 1 wk of birth. Higher doses of plasmid are more tolerogenic, and susceptibility to tolerance is not MHC-restricted. CD8+ T cells from tolerant mice suppress the in vitro Ag-specific immune response of cells from adult mice immunized with pCSP. Similarly, CD8+ T cells from tolerant mice transfer nonresponsiveness to naive syngeneic recipients. These findings clarify the cellular basis and factors contributing to the development of DNA vaccine-induced neonatal tolerance.

Animals↗
PubMed1999

Protein tyrosine phosphorylation: A possible common signaling pathway in human Th1 and Th2 cell clones.

BACKGROUND: It has been reported that protein tyrosine phosphorylation is essential for cytokine production in mouse Th1 cells but not in Th2 cells. However, little is known about the difference of signal transduction between human antigen-specific Th1 and Th2 cell clones. METHODS: Purified protein derivative-specific Th1 and Dermatophagoides farinae-specific Th2 cell clones were established. T cell clones were stimulated with anti-CD3 Abs and further treated with goat antimouse immunoglobulin Abs for cross-linking of TCR/CD3 complex. RESULTS: In contrast to murine Th2 clones, tyrosine phosphorylation including both ZAP-70 and phospholipase-C-Al was necessary for cell activation in both types of human T cell clones. This was further supported by the observation that genistein (protein tyrosine kinase inhibitor) inhibits IFN-A production for Th1 and IL-4 for Th2 in a dose-dependent manner. CONCLUSION: Protein tyrosine phosphorylation is thus an essential component in transducing the activation signal from TCR-CD3 complex both in human Th1 and Th2 cells.

Clone Cells↗
PubMed1999

Chronic Chagas' heart disease in a Japanese-Brazilian traveler. A case report.

A 57-year-old Japanese-Brazilian man, visiting Japan for only 9 days, was admitted to our hospital due to syncope and frequent ventricular premature beats. He grew up in a rural area of Brazil and moved to Sao Paulo in 1959 when he was 20 years old. We suspected chronic Chagas' heart disease, i.e., dilated cardiomyopathy with apical ventricular aneurysm, right bundle branch block with left anterior fascicular block, and various arrhythmias including supraventricular premature beats, ventricular premature beats and non-sustained ventricular tachycardia because he showed typical echo- and electrocardiographic features of the disease. Coronary arteriograms were normal, and left ventriculogram confirmed the existence of apical ventricular aneurysm. A left ventricle biopsy specimen showed hypertrophic cardiac muscle with mild fibrosis. The diagnosis of chronic Chagas' disease was finally confirmed by the demonstration of Trypanosoma cruzi itself in the blood as well as Trypanosoma cruzi antibodies.

Animals↗
PubMed1999

[Multiple renal infarction associated with lupus anticoagulant in a patient with systemic lupus erythematosus].

We report a rare case with multiple renal infarction associated with lupus anticoagulant and SLE. A 20-year old woman presented with remitent fever, butterfly rash and, abdominal pain. Laboratory findings showed leukopenia, positive antinuclear and anti-DNA antibodies, and biological false positive for syphilis. Despite a therapy with prednisolone 25 mg/day, the patient showed hypocomplementemia, high titer of anti-DNA antibody and a development of proteinuria and an elevation of serum creatinine. Renal biopsy revealed no abnormalities. She presented abdominal pain with an elevation of serum LDH. Abdominal dynamic computed tomography demonstrated multiple perfusion defects in both kidneys indicating multiple renal infarction. Brain MRI showed multiple micro infarction in the anterior lobes. She was treated with 80 mg of aspirin and have been in remission for two years. Although there have been reported 18 cases with renal infarction associated with antiphospholipid syndrome, this is the first report in Japan. Renal infarction should be differentiated from renal involvement in patients with SLE who have antiphospholipid antibodies.

Adult↗
PubMed1998

Long-term analysis of allergen-specific T cell clones from patients with asthma treated with allergen rush immunotherapy.

Rush immunotherapy (RI), a modified allergen-specific immunotherapeutic procedure, is an effective treatment for extrinsic (atopic) asthma, although the precise mechanism of its action is unclear. We have thus investigated the effect of RI on T cell response in seven mite-allergen-sensitive asthmatic patients who were successfully treated with RI. The proliferative response to mite allergen profoundly decreased after 3 months of therapy compared to the response before therapy; the response, however, recovered 18 months after RI. Regarding cytokine production patterns of mite-specific T cells, RI brought about a shift in cytokine profiles from Th2 to Th0 or Th1 in mite-specific T cell clones. The data indicate that the efficacy of RI is due to modification of T cell responses to mite antigens. Allergen RI results in the conversion of Th2 to Th1 and Th0 cells and/or selection of Th1 and Th0 cells over Th2 cells and thus may improve both clinical symptoms and airway inflammation in asthmatics.

Adolescent↗
PubMed1998

Modulation by proinflammatory cytokines of Fas/Fas ligand-mediated apoptotic cell death of synovial cells in patients with rheumatoid arthritis (RA).

Synovial cell hyperplasia is a characteristic of patients with RA. Excessive proliferation of RA synovial cells is, in part, responsible for the synovial cell hyperplasia. In addition, synovial cell death that would reduce synovial cell number may be defective, leading to the hyperplasia. Thus, the defective control of cell death as well as cell proliferation may be of central importance in the pathogenesis of RA. In this study we analysed effects of proinflammatory cytokines on Fas/Fas ligand (FasL)-induced synovial cell apoptosis, and evaluated apoptosis-associated protein expression in the synovial cells in patients with RA. RA synovial cells expressed Fas antigen and lymphocytes infiltrating into RA synovium expressed FasL. Apoptotic synovial cells were detected within the sublining layer of RA synovium. Anti-Fas MoAb induced apoptosis of RA synovial cells in vitro, and proinflammatory cytokines tumour necrosis factor-alpha (TNF-alpha) and IL-1beta, but not IL-6 or IL-8, inhibited the anti-Fas-induced apoptosis accompanying up-regulation of Bcl-2 protein expression and reduced expression of CPP32 and ICH-1L. Immunohistochemical study revealed that CPP32 and ICH-1L were expressed weakly in the RA synovial lining cells compared with osteoarthritis (OA) synovial lining cells. Thus, we found that although RA synovial cells could die via apoptosis through Fas/FasL pathway, apoptosis of synovial cells was inhibited by proinflammatory cytokines present within the synovium. Inhibition of apoptosis by the proinflammatory cytokines may contribute outgrowth of synovial cells that leads to pannus formation and the destruction of joints in patients with RA.

Antibodies, Monoclonal↗
PubMed1998

Involvement of simultaneous multiple transcription factor expression, including cAMP responsive element binding protein and OCT-1, for synovial cell outgrowth in patients with rheumatoid arthritis.

OBJECTIVE: To elucidate possible roles of several transcription factors in the pathogenesis of rheumatoid arthritis (RA), the transcription factor expression in RA synovial tissue and their contribution to RA synovial cell functions were studied. METHODS: Single cell suspension of dissociated synovial tissue was cultured to induce in vitro tissue outgrowth of RA synovial cells. Transcription factors were immunohistochemically identified in RA synovial tissue obtained by joint surgery and in the in vitro tissue outgrowth, and confirmed by western blotting and gel shift assays. RESULTS: Immunohistochemical examination of RA synovial tissue revealed simultaneous expression of various transcription factors (NF-kappa B, c-Jun (a component of AP-1), cAMP responsive element binding protein (CREB), and OCT-1). The same set of transcription factors was expressed in the in vitro tissue outgrowth of RA patients. The early passage RA synovial cells were treated with interleukin 1 beta (IL1 beta) and confirmed translocation of transcription factors into the nucleus by western blotting, and their DNA binding activity by gel shift assays. CONCLUSION: This study emphasises the importance of the simultaneous expression of several transcription factors for the hyperactivity of RA synovial cells that leads to tissue outgrowth.

Adult↗