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Biomedical subjects

T Origuchi

Publications and source records attributed to T Origuchi.

At least 37 records · Page 2Linked to original sources
PubMed1999

Successful treatment of rapidly progressive lupus nephritis associated with anti-MPO antibodies by intravenous immunoglobulins.

We report a case of systemic lupus erythematosus (SLE) associated with crescentic glomerulonephritis and myeloperoxidase-specific anti-neutrophil cytoplasmic antibodies (MPO-ANCA). A 34-year-old Japanese female patient diagnosed with SLE developed rapidly progressive renal failure and nephrotic syndrome. Haemodialysis was required to restore renal function. Methylprednisolone pulse therapy followed by plasmapheresis did not suppress the progression of renal failure, so she was treated with high-dose intravenous immunoglobulin (IV-IG) therapy, which was well tolerated and effectively prevented renal failure. A renal biopsy showed diffuse proliferative lupus nephritis (WHO classification IVc) with predominant crescent formation and scant subendothelial immune deposits. These findings indicate that, in addition to lupus nephritis, which usually results from the deposition of circulating or locally formed immune complexes, MPO-ANCA may be involved in the pathogenesis of crescentic glomerulonephritis. Furthermore, we propose that IV-IG is an effective therapy for MPO-ANCA-related renal crisis in lupus nephritis.

Acute Kidney Injury↗
PubMed1999

Inhibitory effect of a new anti-rheumatic drug T-614 on costimulatory molecule expression, cytokine production, and antigen presentation by synovial cells.

The present study was undertaken to investigate the immunoregulatory effects of T-614 (3-formylamino-7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-o ne) on synovial cells in vitro. Synovial cells were cultured with T-614 in the presence or absence of various cytokines. After incubation, the costimulatory molecule expression on synovial cells and cytokine production in culture supernatants were analyzed by an indirect immunofluorescence method and enzyme-linked immunosorbent assay, respectively. We also examined the effect of T-614 on the function of synovial cells as antigen-presenting cells (APCs). The costimulatory molecules including CD54, CD58, and CD106 were constitutionally expressed on the surface of synovial cells. However, neither CD80 nor CD86 nor CD102 was found on the surface, and these costimulatory molecules could not be induced by any cytokines. T-614 itself did not affect the costimulatory molecule expression and cytokine production of unstimulated synovial cells. The stimulation of synovial cells with interferon-gamma (IFN-gamma), interleukin-1beta, or 12-O-tetradecanoyl phorbol 13-acetate enhanced the expression of costimulatory molecules and the proinflammatory cytokine production of these cells. Both the up-regulated expression of these costimulatory molecules and the enhanced production of proinflammatory cytokines were significantly inhibited by T-614. Autologous T cell proliferation in response to purified protein derivative by IFN-gamma-treated synovial cells was significantly suppressed by T-614. T-614 has considerable immunosuppressive effects on synovial cells by inhibiting the costimulatory molecule expression and cytokine production of these cells and the antigen-specific T cell proliferation mediated by the synovial cells. These results suggest that T-614 plays an important immunoregulatory role in rheumatoid synovial tissues.

Adjuvants, Immunologic↗
PubMed1999

Induction of cyclooxygenase-2 in human synovial cells by beta 2-microglobulin.

BACKGROUND: Prostaglandins (PGs) are important mediators of inflammation in arthritis. We evaluated the role of the cycloxygenase-2 (COX-2) enzyme, which regulates PG biosynthesis, in osteoarthropathy associated with hemodialysis-associated amyloidosis (HAA) by characterizing COX-2 expression in beta 2-microglobulin-treated human synovial cells. METHODS: We examined the effects of beta 2-microglobulin (beta 2m), a major constituent protein of amyloid fibrils in HAA, on the COX-2 protein and mRNA expression in human synovial cells using Western blot and reverse transcriptase-polymerase chain reaction. RESULTS: beta 2m selectively increased the biosynthesis of COX-2 protein and induction of COX-2 mRNA in a dose-dependent manner. Immunoabsorption of beta 2m-containing media by anti-beta 2m-specific antibody abrogated beta 2m-mediated COX-2 expression on synovial cells. On the other hand, dexamethasone markedly suppressed the induction of COX-2 protein and mRNA in beta 2m-stimulated synovial cells. CONCLUSIONS: Our results suggest that induction of COX-2 expression by beta 2m may be an important component of the inflammatory process in hemodialysis-associated osteoarthropathy.

Blotting, Western↗
PubMed1998

Serum amyloid A protein induces production of matrix metalloproteinases by human synovial fibroblasts.

Serum amyloid A (SAA) is a precursor protein for amyloid A, which is a constituent for amyloid fibrils in secondary amyloidosis. To determine the role of SAA in the articular destruction in patients with rheumatoid arthritis (RA), we investigated the effects of SAA on the production of matrix metalloproteinases (MMPs) by rheumatoid synovial fibroblasts. SAA stimulated rheumatoid synovial fibroblasts to produce MMP-2 and MMP-3 in a dose-dependent manner. Pretreatment of synovial fibroblasts with cycloheximide prevented SAA-mediated MMP-2 and MMP-3 secretion. When SAA-containing media were immunodepleted by anti-SAA-specific antibody, SAA-mediated MMP secretion was also abrogated. The level of MMP-3 mRNA was increased in SAA-stimulated synovial fibroblasts compared with that of control cells. Our data indicate that SAA is a potent inducer of MMPs in the RA synovium and may play a critical role in the degradation of extracellular matrix in the rheumatoid joint.

Arthritis, Rheumatoid↗
PubMed1997

FK506 potentiates steroid-induced T-cell apoptosis.

BACKGROUND: FK506 and glucocorticoids are used for allograft rejection, graft-versus-host disease, and autoimmune diseases. MATERIALS: We investigated the combined effect of FK506 and glucocorticoids on T-cell apoptosis. RESULTS: Dexamethasone injection in mice reduced the number of CD4+CD8+ thymocytes by increasing DNA fragmentation. Pretreatment with FK506 significantly augmented thymocyte DNA fragmentation induced by dexamethasone injection. Increased thymic apoptosis resulted in the disappearance of CD4+CD8+ thymocytes after FK506/dexamethasone injection. In addition to thymocytes, mature human peripheral blood T cells undergo apoptosis by exposure to dexamethasone in vitro. FK506 synergistically enhanced dexamethasone-mediated apoptosis of human peripheral blood T cells. CONCLUSIONS: Thus, our results showed that FK506 enhanced dexamethasone-induced apoptosis of T cells in vivo and in vitro. This interaction may enhance the therapeutic immunosuppression achieved by these two drugs.

Adult↗
PubMed1997

Beta 2-microglobulin induces stromelysin production by human synovial fibroblasts.

beta 2-Microglobulin (beta 2-m) is a major constituent of amyloid fibrils in hemodialysis-associated amyloidosis (HAA), a serious complication in patients on long-term hemodialysis. The most distinctive pathological feature of HAA is the deposition of amyloid fibrils with subsequent articular inflammation and destruction. However, the pathological role of beta 2-m is not well known at present. We investigated the effects of beta 2-m on the production of proteinases from synovial fibroblasts isolated from patients with rheumatoid arthritis. beta 2-m stimulated synovial fibroblasts to produce stromelysin, a neutral matrix metalloproteinase (MMP-3). The production of MMP-2 and of a tissue inhibitor of metalloproteinase-1 (TIMP-1) were not enhanced by beta 2-m-treated synovial fibroblasts. Stromelysin is capable of degrading several components of the extracellular matrix and believed to be the key enzyme causing articular destruction in inflammatory joint diseases. Our results suggest a novel role for beta 2-m in articular inflammation and destruction mediated by stromelysin in HAA.

Cells, Cultured↗
PubMed1997

Superantigen-induced stromelysin production from rheumatoid synovial cells.

Superantigens activate a large number of T cells in a V beta-restricted manner after binding to MHC class II molecules on the antigen presenting cells (APC). Superantigens also activate APC directly by interacting with their ligands, MHC class II molecules. In the present study, we examined the effects of superantigens on matrix metalloproteinases (MMPs) secretion from rheumatoid synovial fibroblasts. We demonstrated that stimulation of interferon (IFN)-gamma-treated synovial fibroblasts with staphylococcal enterotoxin A (SEA) selectively induced the secretion of stromelysin, a neutral MMP, from synovial fibroblasts. Pretreatment of synovial fibroblasts with cycloheximide, an inhibitor of protein synthesis, prevented MMP-3 secretion from rheumatoid synovial cells suggesting that protein synthesis was required for SEA-induced MMP-3 secretion after SEA binding to MHC class II molecules. Our data suggest that in the synovium, bacterial superantigens are potent inducers of stromelysin which plays a critical role in articular destruction observed in inflammatory joint disease.

Arthritis, Rheumatoid↗
PubMed1996

High seroprevalence of anti-HTLV-I antibody in rheumatoid arthritis.

OBJECTIVE: To investigate the association between human T lymphotropic virus type I (HTLV-I) infection and rheumatoid arthritis (RA) in Nagasaki, an area highly endemic for HTLV-I infection. METHODS: Sera from 113 female patients with RA and 19,796 female blood donors were screened for anti-HTLV-I antibodies with a gelatin particle agglutination kit and confirmed using an immunoblotting kits. RESULTS: The age-adjusted summary odds ratio of HTLV-I infection among RA patients, as compared with blood donors, was 2.8 (95% confidence interval [95% CI] 1.8-4.6). The etiologic fraction, i.e., the proportion of RA in the study population that is attributable to HTLV-I infection, was estimated to be 13.2% (95% CI 5.1-21.2). There was no significant difference in the clinical and laboratory findings between HTLV-I- infected and HTLV-I-uninfected RA patients. CONCLUSION: These epidemiologic findings support the idea that HTLV-I infection is a risk factor for RA, and suggest that approximately 13 % of the cases of RA in females living in Nagasaki are associated with HTLV-I infection.

Adult↗
PubMed1996

Cytokine production by endothelial cells infected with human T cell lymphotropic virus type I.

OBJECTIVE: To investigate the ability of human T cell lymphotropic virus type I (HTLV-I) to infect endothelial cells and induce cytokine production by these cells. METHODS: Human umbilical vein endothelial cells (HUVEC) were cocultured with HTLV-I infected T cell line (MT-2 cells) or uninfected T cell line (CEM cells). RESULTS: Following coculture with MT-2 cells, endothelial cells expressed HTLV-I specific core antigens. Endothelial cells cocultured with MT-2 cells produced significant amounts of several cytokines, including interleukin (IL)-1 alpha, IL-6, granulocyte colony stimulating factor (G-CSF), and granulocyte/macrophage colony stimulating factor (GM-CSF), compared with endothelial cells cocultured with CEM cells. Coculturing of endothelial cells with MT-2 and CEM cells failed to produce detectable amounts of IL-1 beta and tumour necrosis factor alpha (TNF-alpha). The production of cytokines by endothelial cells cocultured with MT-2 cells was more persistent than that by endothelial cells cocultured with CEM cells after several passages. Furthermore, the production was blocked by cocultivation of endothelial cells and MT-2 cells using the Millicell system. Finally, after cocultivation of endothelial cells and MT-2 cells, endothelial cells positive for HTLV-I antigen were stained by anti-GM-CSF antibody. CONCLUSIONS: HTLV-I can infect endothelial cells, resulting in their active production of several cytokines, such as IL-1 alpha, IL-6, G-CSF, and GM-CSF. These findings strongly suggest that the excess production of these cytokines by HTLV-I infected endothelial cells may be involved in the pathogenesis of HTLV-I associated inflammatory diseases.

Cell Line↗
PubMed1995

Synovial cells are potent antigen-presenting cells for superantigen, staphylococcal enterotoxin B (SEB).

There is ample evidence suggesting that superantigens may act as a triggering factor in the pathogenesis of rheumatoid arthritis (RA). We investigated whether superantigen could activate T cells in the presence of synovial cells. T cells were cultured with SEB in the presence of interferon-gamma (IFN-gamma)-treated synovial cells. T cell proliferation and activation were assessed by 3H-thymidine incorporation and IL-2 production. The expression of HLA class II antigens and adhesion molecules on synovial cells was detected by flow cytometer. In the presence of IFN-gamma-treated synovial cells, T cells proliferated vigorously and produced IL-2 in response to SEB. A low SEB-induced T cell response was noticed in the presence of untreated synovial cells. Allogeneic as well as autologous IFN-gamma-treated synovial cells markedly enhanced SEB-induced T cell proliferation. IFN-gamma-treated synovial cells had increased expression of HLA class II antigens and intercellular adhesion molecule-1 (ICAM-1) adhesion molecules. MoAbs towards these antigens markedly inhibited the SEB-induced T cell response. These results indicate that activated synovial cells are potent antigen-presenting cells for SEB to T cells, and that superantigens may play a critical role in the pathogenesis of RA through activated synovial cells.

Antibodies, Monoclonal↗
PubMed1995

Increased levels of serum IgM antibody to staphylococcal enterotoxin B in patients with rheumatoid arthritis.

OBJECTIVE: To investigate the role of superantigen in rheumatoid arthritis (RA) by assaying the serum levels of staphylococcal enterotoxin B (SEB) antibodies. METHODS: Serum IgG and IgM SEB antibodies were measured using an enzyme linked immunosorbent assay (ELISA), and confirmed by Western blot analysis. The T cell receptor V beta (TCR V beta) repertoire was analysed using the reverse transcriptase polymerase chain reaction. RESULTS: RA patients had increased levels of serum IgM SEB antibody compared with normal subjects, patients with systemic lupus erythematosus, Sjögren's syndrome, and Behçet's disease. The titres of rheumatoid factor (RF) showed no correlation with the levels of IgM SEB antibodies, and the levels of SEB antibodies were not inhibited by the addition of human immunoglobulin, or after absorption of RF. RA patients whose disease duration was less than 10 years had greater levels of serum IgM SEB antibodies than those with disease duration more than 10 years. The levels of IgM and IgG SEB antibodies in synovial fluid from RA patients were correlated with those in their sera. Western blot analysis detected IgM and IgG SEB antibodies as a band of approximately 30 kDa molecular size. The percentage of TCR V beta 2, V beta 5.2, and V beta 12 in phytohaemagglutinin stimulated peripheral T cells correlated significantly with the levels of serum IgM SEB antibody in RA patients. CONCLUSION: These results suggest that SEB, one of the superantigens, may have a critical role in the pathogenesis of RA.

Adult↗
PubMed1995

[A male case of primary Sjögren's syndrome with interstitial pneumonitis and interstitial tubulo-nephritis in the absence of dry eye and dry mouth: parotid gland MRI is a useful diagnostic method for Sjögren's syndrome].

Here we report a case of primary Sjögren's syndrome with hilar lymphadenopathy, interstitial pneumonitis and interstitial tubulo-nephritis. A 60-year old man was admitted to our hospital in May 1993 because of general fatigue and fever. He was noted to have hypergammaglobulinemia and had positive antibodies to nuclear antigens since 1990 in the absence of clinical manifestations. Since 9 months before admission, he presented with general fatigue, low grade fever and uveitis. On admission, chest X-ray and CT scan showed bilateral hilar lymphadenopathy and interstitial pneumonitis. The negative results for both serum angiotensin converting enzyme and histological findings of the cervical lymph node and the lung excluded the diagnosis of sarcoidosis. Serological examination exhibited marked elevation of polyclonal IgG level and anti-nuclear antibody, but neither anti-SS-A (Ro) nor anti-SS-B (La) antibody was detected. He did not have symptoms of xerophthalmia and xerostomia. Keratoconjunctivitis sicca was diagnosed by positive Schirmer's and rose bengal tests. His labial gland biopsy demonstrated severe mononuclear cell infiltration around the ducts. MRI findings of the parotid glands revealed heterogeneous and dotted high signal intensity similar to those in fat tissues in the T1- and T2-weighted images. These findings depicted that bilateral parotid gland was extensively destructed and was replaced by lipid tissue. Renal biopsy showed interstitial tubulo-nephritis. On the basis of the above findings, he was diagnosed to have primary Sjögren's syndrome and uveitis. Therefore, MR image of the parotid gland is considered to be a noninvasive and useful method for diagnosis of Sjögren's syndrome.

Humans↗
PubMed1994

The expression of adhesion molecules in thyroid glands from patients with Graves' disease.

We studied the potential role of adhesion molecules in the pathogenesis of Graves' disease. Thyroid specimens of Graves' thyroid glands and control thyroid glands were stained with monoclonal antibodies against adhesion molecules by an immunohistologic method. Thyroid tissues obtained from patients with Graves' disease had an enhanced expression of intercellular adhesion molecule-1 (ICAM-1) on capillary endothelial cells around the thyroid follicles and on postcapillary endothelial cells in lesions with aggregates of mononuclear cells. Positive staining for ICAM-1, lymphocyte function-associated antigen-1 (LFA-1), and very late antigen-4 (VLA-4) was found on the infiltrating mononuclear cells. The postcapillary vascular endothelial cells expressed increased endothelial-leukocyte adhesion molecule-1 (ELAM-1), but not vascular cell adhesion molecule-1 (VCAM-1). VCAM-1 and ELAM-1 were detected on the dendritic-like cells in the germinal centers of lymphoid follicle-like areas. No significant expression of these adhesion molecules was detected on normal thyroid glands. These results suggest that the LFA-1/ICAM-1 and ELAM-1 pathways may be responsible for the migration of mononuclear cells into the thyroid glands of patients with Graves' disease, and that the VLA-4/VCAM-1 pathway plays a critical role in the cellular interactions that lead to the formation of B-memory cells and the excess production of antibodies.

Adult↗
PubMed1994

[Collagen diseases complicated with myelodysplastic syndrome (MDS)--report of three cases].

We presented three cases of collagen diseases complicated with myelodysplastic syndrome (MDS). To our knowledge, MDS following collagen disease is very rare, and only seven cases have been reported previously. First case (a 40-years old woman) had suffered from rheumatoid arthritis, systemic lupus erythematosus and Sjögren's syndrome for 16 years. Second case (a 65-years old woman) had suffered from rheumatoid arthritis for 15-years. Third case (a 63-years old woman) had suffered from progressive systemic sclerosis for 16 years. These patients developed MDS. After onset of MDS, cytopenia progressed rapidly within half a year. In the types of MDS, case 1 and case 2 had refractory anemia and case 3 had refractory anemia with excess of blasts and a preleukemic state. Case 2 had a clonal abnormality of haemopoietic stem cells. It is unlikely that MDS in our cases are caused by mutant agents or irradiation. These results suggest MDS may be contributed to long-term immunodysfunction found in these collagen diseases.

Adult↗
PubMed1992

[Clinical characteristics and prognosis of secondary amyloidosis in patients with rheumatoid arthritis--renal involvement and therapy].

Secondary amyloidosis is an important complication that may have a strong influence on the prognosis of patients with rheumatoid arthritis (RA). We studied 21 RA patients with secondary amyloidosis. The two major initial signs were gastrointestinal symptoms and renal involvement. When 15 of the 21 patients were diagnosed as having secondary amyloidosis, they displayed renal involvement including proteinuria, hematuria and hypercreatininemia. The 15 patients with amyloidosis were either subjected to dialysis or died within 35 months on the average. The causes of death in 13 patients were cardiac failure, gastrointestinal bleeding and infection, which were strongly implicated with renal failure. Dialysis was applied to seven patients. Three of them were maintained with chronic dialysis. We discussed the induction-time and the method of dialysis in patients with amyloidosis secondary to RA.

Adolescent↗