Biomedical subjects

M Kuwana

Publications and source records attributed to M Kuwana.

At least 73 records · Page 4Linked to original sources

PubMed1997

[Toxicity of low-dose methotrexate in rheumatoid arthritis--clinical characteristics in patients with MTX-induced pancytopenia and interstitial pneumonitis].

Pancytopenia and interstitial pneumonitis are one of the most serious and unpredictable adverse effects of low dose, pulse methotrexate (MTX) in treating rheumatoid arthritis (RA). It is important to investigate the historical, clinical or immunologic features associated with the development of such toxicity, in order to use MTX more appropriately. Two hundred eighty four patients (female 230 male 54) with rheumatoid arthritis had been treated with pulse weekly oral MTX with a mean follow-up of 33.2 months. Adverse effects which required the discontinuation of MTX occurred in 47 patients (16.5%). Gastrointestinal toxicity occurred most frequently (14 patients) and liver dysfunction occurred in 9 patients. Four patients (1.4%) developed pancytopenia, and six patients (2.1%) developed interstitial pneumonitis. All patients who developed pancytopenia were old female with long history of active, deforming rheumatoid arthritis, The cumulative dose of MTX ranged from 15 mg to 760 mg at the time pancytopenia developed. Impaired renal function, hypoalbuminemia, and multiple medication were observed, and antinuclear antibodies were positive in most patients. It should be noted that severe stomatitis preceded or accompanied with pancytopenia in all patients. Blood counts returned to the normal level in 7 to 14 days. All patients who developed interstitial pneumonitis were old female. The cumulative dose ranged from 65 mg to 580 mg. Pre-existance of lung diseases, history of adverse effects of other DMARDs, the presence of Raynaud's phenomenon, and antinuclear antibodies appeared to be risk factors for interstitial pneumonitis. All patients recovered with high dose of corticosteroid and mechanical ventilation. Such clinical characteristics that are associated with MTX-induced pancytopenia or interstitial pneumonitis should be reminded in the treatment of rheumatoid arthritis with MTX.

Aged↗

PubMed1996

Enhancement of anti-DNA topoisomerase I autoantibody response after lung cancer in patients with systemic sclerosis. A report of two cases.

Anti-DNA topoisomerase I (anti-topo I) antibody profiles were compared before and after lung cancer in 2 patients with systemic sclerosis (SSc). Both patients developed adenocarcinoma of the lung late in the course of SSc and died of the cancer. Anti-topo I antibody levels, determined by double immunodiffusion and enzyme-linked immunosorbent assay, increased markedly at the time of diagnosis of lung cancer. Furthermore, patients' sera obtained after lung cancer reacted with multiple epitopes on the entire topo I molecule, some of which had not previously been recognized. These results further support the concept that anti-topo I antibody production in SSc patients is due to an antigen-driven process.

Adenocarcinoma↗

PubMed1996

Clinical correlations with HLA type in Japanese patients with connective tissue disease and anti-U1 small nuclear RNP antibodies.

OBJECTIVE: To elucidate the roles of HLA genes in the clinical presentation of patients with connective tissue disease and serum anti-U1 small nuclear RNP antibody. METHODS: HLA class I antigens and HLA class II alleles were determined in 43 Japanese patients with anti-U1 RNP antibody alone, by microcytotoxicity testing and DNA typing, respectively. Prospectively recorded clinical and laboratory features were analyzed in relation to HLA class I and class II types. RESULTS: DQB1*0303 was associated with lupus-related symptoms including fever, malar rash, oral ulcers, hypocomplementemia, and high-titer anti-double-stranded DNA antibody. Other HLA-clinical associations included DR2 with pleuritis, DR4 with hand swelling, and DRB1*0405 with arthritis. CONCLUSION: These HLA-clinical associations explain, in part, the heterogeneous clinical presentation in patients with anti-U1 RNP antibody.

Adolescent↗

PubMed1996

Anti-U5 small nuclear ribonucleoprotein (snRNP) antibodies: a rare anti-U snRNP specificity.

We surveyed for autoantibodies to the U small nuclear ribonucleoproteins (snRNPs) in sera from 1171 patients with various connective tissue diseases by immunoprecipitation assay. We found serum, termed LaJ, which principally recognized the U5 snRNP from one patient with systemic sclerosis-polymyositis overlap syndrome. Anti-LaJ serum immunoprecipitated predominantly U5 snRNA from a 32PO4-labeled HeLa cell extract and at least five U5-specific proteins as well as the Sm core proteins from a [35S]methionine-labeled extract. Anti-LaJ serum immunoprecipitated both U5 snRNA and these five proteins in identical fractions at 15-20S by parallel sucrose gradient, suggesting physical association of these two components. Thus, we concluded that anti-LaJ serum contained antibody specific to the U5 snRNP. Antibodies specific to U5 snRNP were found in a single serum; in contrast, the prevalence of anti-U1 snRNP and anti-Sm antibody was considerably higher. Thus, the specific proteins of the U5 snRNP are rare targets for autoantibodies in patients with connective tissue disease.

Antibodies, Antinuclear↗

PubMed1996

Nodular regenerative hyperplasia of the liver in a patient with systemic sclerosis.

We report on a 33-year-old female patient with systemic sclerosis and nodular regenerative hyperplasia of the liver (NRHL). A needle biopsy of the patient's liver did not reveal the histology of NRHL or liver cirrhosis at her first visit to our hospital, when portal hypertension was demonstrated by percutaneous transhepatic portography. After 11 years, the patient died of hepatic and renal failure. At the time of autopsy, multiple nodules were found in the liver, and a microscopic examination showed a histology compatible with NRHL. It is suggested that the immunological disturbance was related to the patient's portal hypertension and NRHL.

Adult↗

PubMed1996

Differences in mechanisms for cell-free NADPH oxidase activation between arachidonate and sodium dodecyl sulfate.

Mechanisms for the cell-free activation of NADPH oxidase by sodium dodecyl sulfate (SDS) and arachidonate were compared in relation to their responsiveness to short chain diacylglycerols. The plasma membrane and cytosol prepared from guinea pig neutrophils were used for the cell-free system. The activation of NADPH oxidase by SDS was enhanced about 5- to 10-fold by 1,2-dioctanoylglycerol (diC8), but not by either 1,2-dihexanoylglycerol (diC6) or 1,2-didecanoylglycerol (diC10). However, none of these diacylglycerols potentiated the NADPH oxidase activation by arachidonate. The maximal extent of activation by the combination of SDS and diC8 was similar to that by arachidonate alone. In the presence of sufficient amounts of diC8 and SDS, GTP gamma S potentiated the activation of NADPH oxidase. The potentiating activity of diC8 was preserved in the membrane fraction, not in the cytosol fraction. These results suggest that arachidonate may possess the functions of both SDS and diC8 in the activation. In addition, diC8 and GTP gamma S seem to independently enhance the NADPH oxidase activation.

Animals↗

PubMed1996

Phospholipid-dependent anti-beta 2-glycoprotein I (beta 2-GPI) antibodies and antiphospholipid syndrome.

A portion of anticardiolipin antibodies is defined as phospholipid-dependent anti-beta 2-glycoprotein I (beta 2-GPI) antibodies and recognizes the conformationally altered beta 2 GPI which interacts with anionic phospholipids. We studied the clinical significance of IgG phospholipid-dependent anti-beta 2-GPI antibodies in patients with antiphospholipid syndrome (APS). The subjects consisted of 60 APS patients. IgG phospholipid-dependent anti-beta 2-GPI antibodies were detected by ELISA in 32 of the 60 patients (53%). Significantly higher incidences of prolonged APTT and lupus anticoagulants were found in patients with these anti-beta 2-GPI antibodies. Moreover, significantly lower incidences of malar rash, serositis, LE cell preparation and anti-Sm antibodies were found in patients with these anti-beta 2-GPI antibodies. It was found that 88% of the patients with these anti-beta 2-GPI antibodies satisfied less than five of the revised criteria items for the classification of SLE. These findings indicate the clinical characteristics of APS patients with IgG phospholipid-dependent anti-beta 2-GPI antibodies.

Adult↗

PubMed1996

Reevaluation of enzyme-linked immunosorbent assay with ultraviolet-treated polystyrene microtiter plates for measurement of antibodies to dsDNA.

We reevaluated the efficacy of enzyme-linked immunosorbent assay (ELISA) with ultraviolet (UV)-treated polystyrene microtiter plates (UV-ELISA) for the detection of human serum anti-dsDNA antibodies. The subjects consisted of 38 patients with systemic lupus erythematosus (SLE). The titers of IgG serum anti-dsDNA antibodies by UV-ELISA were significantly (p < 0.01) higher in sera from 26 active SLE patients than in those from 12 inactive SLE patients. ELISA with poly-L-lysine coated microtiter plates (PLL-ELISA) revealed the similar results. However, the background ratio was only 1.0 +/- 0.9% by UV-ELISA, which was significantly (p < 0.01) lower than that by PLL-ELISA (16.8 +/- 10.8%). These results demonstrated the efficacy of ELISA with UV-treated polystyrene microtiter plates for the measurement of human serum anti-dsDNA antibodies in patients with SLE.

Antibodies, Antinuclear↗

PubMed1995

T and B cell collaboration is essential for the autoantibody response to DNA topoisomerase I in systemic sclerosis.

To elucidate the mechanisms controlling anti-DNA topoisomerase I (topo I) antibody production in patients with systemic sclerosis (SSc), in particular the role of interactions between topo I-specific Th cells and B cells, we established an in vitro system for the analysis of anti-topo I antibody production. In vitro anti-topo I antibody synthesis in PBMC cultures was induced by recombinant topo I and PWM, and was measured by a topo I-specific ELISA. Anti-topo I antibody was detected in PBMC culture supernatants from 11 (61%) of 18 anti-topo I-positive SSc patients. In contrast, anti-topo I antibody was not detected in the PBMC culture supernatants from 4 anti-topo I-negative SSc patients or 10 healthy donors. Characterization of in vitro anti-topo I antibody production showed that 1) the anti-topo I antibody isotype produced was IgG; 2) the anti-topo I antibody levels in culture supernatants correlated with those in patients' sera; 3) CD4+ T cells were necessary for antibody synthesis; and 4) antibody synthesis was restricted by HLA-DR, but not by HLA-DQ or DP. In addition, separation of cultured T and B cells by a semipermeable membrane or culture with anti-CD40 ligand mAb blocked in vitro anti-topo I antibody production. These results indicate that a contact-mediated and HLA-DR-restricted collaboration between topo I-specific T and B cells is essential for in vitro anti-topo I antibody production in a subset of SSc patients.

Adult↗

PubMed1995

Major histocompatibility complex class II gene associations with anti-U1 small nuclear ribonucleoprotein antibody. Relationship to immunoreactivity with individual constituent proteins.

OBJECTIVE: To better define immunogenetic associations with the anti-U1 ribonucleoprotein (U1 RNP) autoantibody response. METHODS: HLA class II alleles were determined by genotyping in 49 Japanese rheumatic disease patients with anti-U1 RNP antibody and 43 race-matched healthy controls. Immunoreactivities to U1 RNP constituent proteins (70K, A, B/B', and C) were detected by immunoblots using purified HeLa cell Sm antigen, and antibody titer was determined by passive hemagglutination assay. RESULTS: DQB1*0302 was significantly more frequent in anti-U1 RNP-positive patients than in controls (43% versus 14%; odds ratio [OR] = 4.6, corrected P = 0.03). All anti-U1 RNP-positive patients had either a DQB1*0601, *0602, *0301, *0302, or *0303 allele, which share tyrosine at position 30, and the amino acid sequence Thr, Arg, Ala, Glu, Leu, Asp, and Thr at positions 71-77 in the DQB1 beta 1 domain. In contrast, one of these alleles was found in 81% of the controls (OR = 24, P = 0.002). In addition, anti-U1 RNP antibody was associated with unique DQB1*0302; DRB1*0401 haplotype. Anti-70K reactivity and antibody titer were positively associated with a basic amino acid residue, arginine or histidine, at position 13 (DR2 or DR4) and were negatively associated with the amino acid sequence Ile, Leu, Glu, and Asp at positions 67-70, which was present in some of the DR5-, DR6-, and DR8-associated alleles, in the DRB1 beta 1 domain. Anti-C reactivity was strongly associated with DR2, particularly with DRB1*1502. CONCLUSION: The several shared epitopes located on HLA-DRB1 and DQB1 genes control the anti-U1 RNP autoantibody response.

Amino Acid Sequence↗

PubMed1995

Detection of anti-DNA topoisomerase I antibody by an enzyme-linked immunosorbent assay using overlapping recombinant polypeptides.

Five recombinant fusion proteins with overlapping amino acid sequences encompassing the entire DNA topoisomerase I (topo I) molecule were generated, purified, and used as antigens for an enzyme-linked immunosorbent assay (ELISA). IgG, IgA, IgM, and "total" (total of IgG, IgA, and IgM isotypes) anti-topo I antibodies were measured using a mixture of these five fusion proteins in 73 systemic sclerosis (SSc) sera positive for anti-topo I antibody by double immunodiffusion (DID) and 184 control sera negative for anti-topo I antibody by DID. Fragment-specific anti-topo I antibodies were also measured by ELISA using each topo I recombinant protein as antigen. IgG, IgA, IgM, and total anti-topo I antibodies were detected in 67 (92%), 56 (77%), 16 (22%), and 70 (96%) of 73 SSc sera positive for anti-topo I antibody by DID, respectively. The specificity of the total anti-topo I ELISA was 99% when compared with DID. The total anti-topo I ELISA levels were strongly correlated with DID titers (r = 0.907, P < 0.0001). Three sera which recognized a conformational epitope on native topo I or had predominantly IgM anti-topo I antibody showed a false-negative result with the total anti-topo I ELISA. Three SSc sera negative for anti-topo I antibody by DID were positive by the total anti-topo I ELISA, and two were confirmed to recognize the N-terminus of topo I. IgG and IgA antibody levels to the N-terminal and central portion of topo I were correlated with each other, but those to the C-terminus were not. These findings indicate that the ELISA using recombinant fusion proteins is a highly sensitive and specific alternative to conventional DID for the detection of anti-topo I antibody.

Adult↗

PubMed1995

Massive pericardial effusion in scleroderma: a review of five cases.

Medical records of five patients with scleroderma (SSc), each of whom had pericardial effusion with an estimated volume of more than 200 ml, were reviewed to study the clinical and immunological significance of massive pericardial effusion in SSc. Diffuse SSc (4/5), with a wide area of pigmentation (4/5), flexion contracture (4/5), oesophageal hypomotility (5/5), pulmonary fibrosis (4/5) and autoantibodies to topoisomerase I (3/5) were the common features in this group. High protein, lactate dehydrogenase and low white blood cell count were the characteristics of pericardial fluid. None of the patients had signs of acute pericarditis. Four of the five cases died within 9 months of the diagnosis of pericarditis; two with renal failure, one with cardiac tamponade and another with sudden death. The pericarditis in diffuse SSc, especially in cases with anti-topoisomerase I, may be characterized by a chronic form of pericarditis with poor prognosis, often complicated by renal failure.

Adult↗

PubMed1995

HLA class II genes associated with anticentromere antibody in Japanese patients with systemic sclerosis (scleroderma).

OBJECTIVE: To define further HLA class II gene associations with anticentromere antibody (ACA), a major serum antinuclear antibody in patients with systemic sclerosis (SSc). METHODS: HLA class II genes were determined using polymerase chain reaction/restriction fragment length polymorphisms in 94 Japanese patients with SSc (22 ACA positive and 72 ACA negative) and 50 race matched normal control subjects. RESULTS: Frequency of DQB1*0501 was increased in ACA positive SSc patients compared with ACA negative SSc patients (36% versus 13%; p = 0.02, odds ratio = 4.0, 95% confidence interval 1.1 to 13.9), but the association of ACA with a polar amino acid at position 26 in the DQB1 beta 1 domain, which was demonstrated in white North Americans, was not observed in Japanese. The DRB1*0101, *0405, and *1302 alleles were associated with high ACA titres, whereas DRB1*1502 was associated with low ACA titres and a low frequency of centromere protein C (CENP-C) reactivity. CONCLUSIONS: These results suggest that the ACA response is associated with multiple HLA class II genes and that ACA positive SSc patients are heterogeneous in terms of immunogenetic background.

Alleles↗

PubMed1995

T cell proliferative response induced by DNA topoisomerase I in patients with systemic sclerosis and healthy donors.

The in vitro T cell proliferative response to DNA topoisomerase I (topo I) was examined in 26 systemic sclerosis (SSc) patients with anti-topo I antibody, 10 SSc patients without anti-topo I antibody, and 21 healthy donors. Using recombinant fusion proteins encompassing the entire human topo I amino acid sequence, a topo I-specific proliferative response was detected in PBMC cultures from 25 (96%) anti-topo I-positive SSc patients, 4 (40%) anti-topo I-negative SSc patients, and 13 (62%) healthy donors. Molecular typing at MHC class II loci revealed that all SSc patients and healthy donors having either DRB1*1501,2 (DR15), DRB1*1101,3,4 (DR11), or DRB1*07 (DR7) were responders. Characterization of the topo I-induced T cell proliferative response showed that (a) the responding cells were CD4+ T cells; (b) antigen-presenting cells were necessary for the response; (c) the response was restricted by HLA-DR, and to a lesser extent by HLA-DQ; and (d) the estimated frequency of the responding T cells determined by limiting dilution analysis was 1/9,277-1/24,853. PBMC cultures from anti-topo I-positive SSc patients showed a high T cell proliferative response after only 3 d of culture with topo I. Anti-topo I-negative SSc patients and healthy donors had no proliferative response after 3 d, but did respond after 7 d of culture. T cell proliferative responses to six truncated topo I fragments tested individually showed different patterns of T cell proliferation that were dependent upon the responder's HLA-DR alleles. These results indicate that T cells reactive with topo I are components of the normal T cell repertoire, and that the topo I-specific T cell proliferative response is not associated with the presence or absence of SSc or anti-topo I antibody, but is restricted by MHC class II alleles.

Adult↗

PubMed1995

Disease distribution of beta 2-glycoprotein I-dependent anticardiolipin antibodies in rheumatic diseases.

We investigated the clinical significance of IgG beta 2-glycoprotein I (GPI)-dependent anticardiolipin antibodies (aCL) in rheumatic diseases. Three hundred and seventeen patients were entered. They consisted of 133 patients with SLE, 60 with RA, 45 with SSc, 37 with PM, 23 with overlap syndrome (overlap), and 19 with unclassified connective tissue disease (UCTD). IgG beta 2-GPI-dependent aCL were examined by ELISA. While IgG beta 2-GPI-dependent aCL were detected in 13% of patients with SLE, these aCL were positive in two patients with SSc, two with overlap and 14 with UCTD. A significant association between IgG beta 2-GPI-dependent aCL and thrombosis was found. Clinical manifestations were studied in 32 patients with secondary APS based on SLE and 14 with primary APS (PAPS). Incidence of malar rash, arthritis, renal disorder, leucopenia, immunological disorders and hypocomplementemia were significantly less frequent in patients with PAPS. IgG beta 2-GPI-dependent aCL were detected in all patients with PAPS and in 34% of secondary APS. This difference was significant. These data suggest that IgG beta 2-dependent aCL are useful for identifying a subset in patients with APS.

Adult↗

PubMed1995

Autoantibodies to topoisomerase I in a patient with systemic lupus erythematosus without features of scleroderma.

We report a woman with systemic lupus erythematosus (SLE) with diffuse proliferative glomerulonephritis and anti-dsDNA antibodies whose serum contained autoantibodies specific for the phosphorylated form of RNA polymerase II (RNAP IIO), Su and ribosomal P antigen, as well as anti-topoisomerase I antibodies, a marker for scleroderma (SSc). Over 6 years, the patient exhibited clinical manifestations consistent with SLE without clinical evidence of scleroderma. The reactivity of her serum autoantibodies with the phosphoproteins ribosomal P, topoisomerase I, and RNAP IIO is consistent with recognition of autoepitopes comprised in part of phosphate groups. This may explain the unexpected coexistence of marker autoantibodies for SLE and scleroderma, possibly with implications for the mechanisms of autoantibody generation.

Adult↗

PubMed1995

Clinical significance of phospholipid-dependent anti-beta 2-glycoprotein I (beta 2-GPI) antibodies in systemic lupus erythematosus.

We investigated the clinical significance of IgG phospholipid-dependent anti-beta 2-glycoprotein I (beta 2-GPI) antibodies in patients with SLE. The study population consisted of 140 patients with SLE. Sera were examined for IgG phospholipid-dependent anti-beta 2-GPI antibodies by ELISA. IgG phospholipid-dependent anti-beta 2-GPI antibodies were detected in 21 of 140 patients (15%) and remained positive from 4 to 98 months. Significantly higher incidences of thrombosis, intrauterine fetal loss, thrombocytopenia, patients with antiphospholipid syndrome (APS), prolonged APTT, BFP-STS and hemolytic anemia were found in SLE patients with phospholipid-dependent anti-beta 2-GPI antibodies. Moreover, significantly lower incidences of malar rash and serositis were found in SLE patients with phospholipid-dependent anti-beta 2-GPI antibodies, and the majority of these patients satisfied four or five of the revised criteria items of the American Rheumatism Association. These differences were not observed when we compared clinical manifestations in anticardiolipin antibody-positive patients with those in antibody-negative patients by conventional ELISA. These results indicated that SLE patients with IgG phospholipid-dependent anti-beta 2-GPI antibodies show an unique form of SLE.

Adult↗

PubMed1995

[Efficacy of beraprost sodium on Raynaud's phenomenon in patients with systemic sclerosis].

Raynaud's phenomenon is an important clinical manifestation in patients with systemic sclerosis (SSc). No effective therapy, however, has been established for this phenomenon. Beraprost sodium, a stable prostacycline (PGI2) analogue, has been reported to improve hemorrheological impairment in patients with rheumatic diseases. In this study, we, therefore, examined the efficacy of beraprost sodium on Raynaud's phenomenon in 30 patients with SSc. Sixty micrograms per day of beraprost sodium was found to be effective in 14 patients (47%) in the period of 15.0 +/- 12.5 weeks. Raynaud's phenomenon in patients who responded to beraprost sodium was characterized by infrequent nail fold thrombosis and narrower hand areas affected by Raynaud's phenomenon, with mild secondary symptoms such as pain. These results indicate that beraprost sodium is effective for mild forms of Raynaud's phenomenon in patients with SSc.

Adult↗