Anti-signal recognition particle antibody in patients without inflammatory myopathy: a survey of 6180 patients with connective tissue diseases.

OBJECTIVES: To clarify the prevalence of anti-signal recognition particle (anti-SRP) antibody in connective tissue diseases (CTDs) and investigate the clinical characteristics of patients without inflammatory myopathy. METHOD: Sera from 6180 patients with CTD were examined by immunoprecipitation (IPP) assays, and the records of patients positive for anti-SRP antibody were reviewed retrospectively. The antibody against the 54-kDa protein of SRP (SRP54) was quantified by enzyme-linked immunosorbent assay (ELISA) in patients with anti-SRP antibody. RESULTS: Of the 28 patients positive for anti-SRP antibody, nine (32.1%) did not have inflammatory myopathy. The clinical diagnoses and characteristics of those patients varied considerably. In patients with inflammatory myopathy, the index of anti-SRP54 was much higher than in those without myopathy (1.15 vs. 0.46; p = 0.036). CONCLUSIONS: The prevalence of anti-SRP antibody was 0.5% in a cohort of Japanese patients with CTD, and one-third of them did not have inflammatory myopathy. Sera from patients with inflammatory myopathy recognized SRP54 more strongly than in those without myopathy.

Clinical associations with autoantibody reactivities to individual components of U1 small nuclear ribonucleoprotein.

The reactivities to individual U1 small nuclear ribonucleoprotein (snRNP) components and their relationship to clinical features in patients with anti-U1 snRNP antibodies were examined. We evaluated 114 patients with connective tissue disease whose sera were positive for anti-U1 snRNP antibodies, but negative for anti-Sm antibodies. Antibodies to the U1 snRNP polypeptides 70K, A, and C were detected using subunit-specific enzyme-linked immunosorbent assays and antibodies to U1 small nuclear RNA (snRNA) were identified by an immunoprecipitation assay using deproteinized HeLa cell extracts. The clinical features were retrospectively obtained by chart review and prospectively collected after study entry. The pattern of antibody reactivities to U1 snRNP components varied among patients. The frequency of anti-70K, anti-A, anti-C, and anti-U1 snRNA antibodies was 60%, 86%, 74%, and 46%, respectively. There was no relationship between each reactivity and the clinical findings, but the presence of reactivities to increasing numbers of U1 snRNP components was correlated with sclerodactyly, shortness of the sublingual frenulum, esophageal dysfunction, and a lack of persistent proteinurea (p < 0.05 for all comparisons). The detection of autoantibody reactivities to individual components of the U1 snRNP particle is potentially useful for predicting the clinical course in patients with connective tissue disease and anti-U1 snRNP antibodies.

Successful treatment of refractory polymyositis with the immunosuppressant mizoribine: case report.

We describe a patient who presented with polymyositis with anti-Jo-1 antibodies at 18 years after the onset of rheumatoid arthritis and was successfully treated with the immunosuppressive drug mizoribine at the time of exacerbation. She had developed diabetes mellitus, cerebral infarction, and myocardial infarction after high-dose steroid therapy was initiated. Therefore, an immunosuppressant was preferred as the second-line agent. Treatment with 150 mg/day of mizoribine and 8 mg/day of prednisolone resulted in eventual normalization of muscle enzyme levels. Mizoribine is a purine antimetabolite that inhibits T cell activation/proliferation and B cell proliferation. The potential efficacy of mizoribine for polymyositis was suggested by this case.

Clinical characteristics of cytomegalovirus infection in rheumatic diseases: multicentre survey in a large patient population.

OBJECTIVE: To survey and elucidate the clinical characteristics of CMV infection in rheumatic disease patients. METHODS: A detailed questionnaire survey on CMV infection was carried out against rheumatic disease patients hospitalized in member hospitals, and the obtained clinical and/or laboratory data were analysed. RESULTS: Out of 7377 patients, 151 were diagnosed as having CMV infection. The underlying diseases ranged broadly, but SLE, microscopic polyangiitis, and dermatomyositis were the most common. Four were diagnosed histopathologically, and the others via positive CMV antigenaemia. In addition to oral corticosteroid for all but one patient, 81 were treated with pulsed methylprednisolone (MPSL), 64 with cyclophosphamide (CYC) and 36 with other immunosuppressants. Forty-four had a fatal outcome, for which presence of clinical symptoms, other infectious complications, lymphopenia, an older age (>59.3 yrs) and the use of pulsed MPSL were significant risk factors (P < 0.05) by univariate analysis. Multivariate analysis retained the first three (P < 0.05). The CMV antigenaemia count was significantly higher for the symptomatic than asymptomatic [10.1 (0.0-2998.0) vs 4.0 (1.3-1144.4)/10(5) PMNs, respectively, P < 0.05; threshold count: 5.6/10(5) PMNs]. No treatment benefit by anti-viral agent was observed as for survival. CONCLUSION: CMV infection was mostly diagnosed by antigenaemia, and occurred among patients under strong immunosuppressive therapy using pulsed MPSL and/or immunosuppressants. Lymphopenia, presence of symptoms and other infections are significant risk factors for a poor outcome and pulsed MPSL and an older age may predict it. Patients were prone to be symptomatic with anti-genaemia count over 5.6/10(5) PMNs.

Clinical characteristics of Japanese patients with anti-OJ (anti-isoleucyl-tRNA synthetase) autoantibodies.

OBJECTIVES: The clinical and laboratory characteristics of seven patients with anti-aminoacyl-tRNA synthetase (ARS) autoantibodies, specifically anti-OJ (anti-isoleucyl-tRNA synthetase), were examined and compared with previously published findings. METHODS: Serum samples from 1135 Japanese patients with various autoimmune diseases and 48 normal individuals were screened for anti-OJ antibodies using RNA and protein immunoprecipitation assays. The patients whose sera contained anti-OJ antibodies were assessed regarding clinical symptoms, clinical course, laboratory findings, chest radiography and chest computed tomography. RESULTS: Sera from seven patients were found to contain anti-OJ antibodies. These autoantibodies were associated with interstitial lung disease (ILD) and myositis. The diagnoses of the seven patients were idiopathic interstitial pneumonias (IIPs) in three, polymyositis (PM) in three and PM-rheumatoid arthritis (RA) overlap in the remaining one. All patients had ILD, but muscle weakness and polyarthritis were seen only in four. Raynaud's phenomenon and sclerodactyly were absent in all patients. CONCLUSIONS: These results indicate that the presence of anti-OJ autoantibodies may distinguish a subtype of anti-ARS syndrome that is more closely associated with ILD than myositis or Raynaud's phenomenon.

Autoantibody to CD40 ligand in systemic lupus erythematosus: association with thrombocytopenia but not thromboembolism.

OBJECTIVES: To examine the prevalence, clinical associations and pathogenic roles of autoantibodies to CD40 ligand (CD40L) in patients with systemic lupus erythematosus (SLE). METHODS: Plasma anti-CD40L antibodies from 125 patients with SLE, 24 with primary antiphospholipid syndrome (APS) and 90 with idiopathic thrombocytopenic purpura (ITP) and from 62 healthy individuals were measured with an enzyme-linked immunosorbent assay (ELISA). HeLa cells transfected with human CD40L cDNA (HeLa/CD40L) were used to confirm the presence of anti-CD40L autoantibodies. The effect of anti-CD40L antibodies on the CD40L-CD40 interaction was evaluated by observing CD40L-induced IkappaB activation in CD40-expressing fibroblasts. RESULTS: Anti-CD40L autoantibody was detected in seven (6%) SLE, three (13%) primary APS and 11 (12%) ITP patients, but in no healthy controls. Antibody binding in an ELISA was competitively inhibited by membrane components of HeLa/CD40L. Anti-CD40L antibody-positive IgG specifically bound the surface of living HeLa/CD40L, as shown by flow cytometry. The frequency of thrombocytopenia was significantly higher in SLE patients with the anti-CD40L antibody than in those without (100 vs 14%; P<0.00001), whereas there was no association between the anti-CD40L antibody and thrombosis. Binding of the anti-CD40L antibodies in patients' plasma to CD40L was competitively inhibited by a series of mouse anti-CD40L monoclonal antibodies. Anti-CD40L antibody-positive IgG failed to inhibit CD40L-induced IkappaB activation. CONCLUSIONS: Anti-CD40L autoantibody is associated with thrombocytopenia but not thromboembolism. Our findings are potentially useful in understanding the complex roles of CD40L in the pathophysiology of thrombosis and haemostasis as well as the thromboembolic complications that occur during treatment with anti-CD40L humanized antibody.

Clinical characteristics of Japanese patients with anti-PL-7 (anti-threonyl-tRNA synthetase) autoantibodies.

OBJECTIVE: The clinical and laboratory features of seven Japanese patients with anti-aminoacyl-tRNA synthetase (ARS) autoantibodies against PL-7 (anti-threonyl-tRNA synthetase) were analyzed and compared with previously published findings. METHODS: Serum samples from 1,135 Japanese patients with various autoimmune diseases were screened for anti-PL-7 antibodies using RNA and protein immunoprecipitation assays. The patients whose sera contained anti-PL-7 antibodies were assessed regarding clinical symptoms and clinical course. RESULTS: Sera from seven patients were found to have anti-PL-7 antibodies. These autoantibodies were associated with polymyositis/dermatomyositis (PM/DM) and/or interstitial lung disease (ILD). The clinical diagnoses of these seven patients were PM - systemic sclerosis (SSc) overlap (5 patients), DM (1 patient) and idiopathic pulmonary fibrosis (IPF) (1 patient). All patients had ILD with a chronic course and six also had arthritis (85%) and five sclerodactyly (71%). CONCLUSIONS: These results indicate that anti-PL-7 autoantibodies are closely associated with PM-SSc overlap as well as ILD, arthritis and sclerodactyly in our series of Japanese patients.

Successful treatment of recurrent intracardiac thrombus in Behçet's disease with immunosuppressive therapy.

Behçet's disease (BD) is a chronic multisystem inflammatory disorder characterized by recurrent oral and genital ulcers, skin eruptions and uveitis. Neurological, gastrointestinal, and musculoskeletal systems are also involved. Although venous and arterial vasculitis occur in up to one-third of patients, intracardiac thrombus is a very rare complication. We herein report the case of a 46-year-old man with BD who presented with a large right atrial thrombus. Within a month after surgical removal, the thrombus recurred and was successfully treated with immunosuppressants that included prednisolone and cyclophosphamide.

Lack of circulating autoantibodies to bone morphogenetic protein receptor-II or activin receptor-like kinase 1 in mixed connective tissue disease patients with pulmonary arterial hypertension.

OBJECTIVES: To examine whether autoantibodies against bone morphogenetic protein receptor-II (BMPR-II) or activin receptor-like kinase 1 (ALK-1) are associated with pulmonary arterial hypertension (PAH) in patients with mixed connective tissue disease (MCTD). METHODS: We studied sera from 37 MCTD patients with or without PAH, six patients with idiopathic PAH, and 30 healthy controls. Circulating anti-BMPR-II and anti-ALK-1 antibodies were detected using immunoprecipitation of recombinant antigens generated by in vitro transcription/translation and indirect immunofluorescence of cultured cells that were induced to express these antigens by gene transfer. Anti-BMPR-II antibodies were further examined by immunoprecipitation and immunoblotting using a recombinant fragment of the extracellular domain of BMPR-II. RESULTS: Serum anti-BMPR-II and anti-ALK-1 autoantibodies were not detected in MCTD patients irrespective of the presence or absence of PAH, or in patients with idiopathic PAH. CONCLUSIONS: Our finding does not support the hypothesis that autoantibody-mediated dysregulation of signals through BMPR-II or ALK-1 contributes to the development of PAH in patients with connective tissue diseases.

Autoantibodies from primary biliary cirrhosis patients with anti-p95c antibodies bind to recombinant p97/VCP and inhibit in vitro nuclear envelope assembly.

We have reported previously that p95c, a novel 95-kDa cytosolic protein, was the target of autoantibodies in sera of patients with autoimmune hepatic diseases. We studied 30 sera that were shown previously to immunoprecipitate a 95 kDa protein from [(35)S]-methionine-labelled HeLa lysates and had a specific precipitin band in immunodiffusion. Thirteen sera were available to test the ability of p95c antibodies to inhibit nuclear envelope assembly in an in vitro assay in which confocal fluorescence microscopy was also used to identify the stages at which nuclear assembly was inhibited. The percentage inhibition of nuclear envelope assembly of the 13 sera ranged from 7% to 99% and nuclear envelope assembly and the swelling of nucleus was inhibited at several stages. The percentage inhibition of nuclear assembly was correlated with the titre of anti-p95c as determined by immunodiffusion. To confirm the identity of this autoantigen, we used a full-length cDNA of the p97/valosin-containing protein (VCP) to produce a radiolabelled recombinant protein that was then used in an immunoprecipitation (IP) assay. Our study demonstrated that 12 of the 13 (93%) human sera with antibodies to p95c immunoprecipitated recombinant p97/VCP. Because p95c and p97 have similar molecular masses and cell localization, and because the majority of sera bind recombinant p97/VCP and anti-p95c antibodies inhibit nuclear assembly, this is compelling evidence that p95c and p97/VCP are identical.

Differences in autoantibody response to Th/To between systemic sclerosis and other autoimmune diseases.

OBJECTIVE: To examine differences in autoantibody response and immunogenetic background between patients with systemic sclerosis (SSc) and those with other autoimmune diseases who had serum anti-Th/To antibodies. METHODS: Serum samples from 1048 Japanese patients with various autoimmune diseases were screened for anti-Th/To antibodies using RNA and protein immunoprecipitation assays. The reactivity to RNase P subunits was examined by immunoprecipitating (35)S labelled recombinant Rpp38, Rpp30, and hPop1 produced by in vitro transcription and translation. HLA-DRB1, DQB1, and DPB1 alleles were identified using a polymerase chain reaction followed by a restriction fragment length polymorphism assay. RESULTS: Serum anti-Th/To antibodies were detected in 14 of 303 patients with SSc and seven of 745 patients without SSc (4.6% v 0.9%; p=0.0003). Similar percentages of patients with and without SSc showed immunoreactivity to Rpp38 and Rpp30, but more patients with SSc than patients without SSc showed a reactivity to hPop1 (93% v 14%; p=0.002). In patients with anti-Th/To antibodies DRB1*1502 or *0802 was detected more often, and the DRB1*0405-DQB1*0401 haplotype less often in patients with SSc than in patients without SSc (79% v 14%, p=0.02, and 7% v 71%, p=0.01, respectively). CONCLUSIONS: Anti-Th/To antibodies were detected in a small proportion of autoimmune patients lacking clinical features related to SSc. A close relationship between disease expression and anti-hPop1 reactivity as well as HLA class II alleles in anti-Th/To positive patients suggests that the process of anti-Th/To antibody production may be different between patients with and those without SSc.

A case of systemic lupus erythematosus presenting with rectal ulcers as the initial clinical manifestation of disease.

Gastrointestinal involvement is often seen in patients with systemic lupus erythematosus (SLE). All parts of the gastrointestinal tract may be affected. However, rectal involvement at onset is rare. We describe here a case of SLE in which rectal ulcers due to vasculitis occurred as the initial manifestation of the disease without involvement of any other organ. The ulcers worsened, along with the appearance of lupus nephritis 5 years later When steroid therapy was initiated, there was rapid clinical and radiographic improvement. Our case suggests that rectal ulcer is a rare but important complication of SLE and can represent the initial and sole clinical manifestation of the disease.

Severe hypertension associated with multiple intrarenal microaneurysms in a patient with systemic lupus erythematosus and antiphospholipid antibodies.

Abstract A 26-year-old Japanese woman with systemic lupus erythematosus (SLE) developed severe hyperten-sion and an increased active renin concentration (ARC), ischemic colitis, and splenic infarction. She had antiphospholipid antibodies (APA), multiple intrarenal microaneurysms, and multiple stenoses of the mesenteric arteries. Combination therapy with antihypertensive agents, aspirin, warfarin, and corticosteroids (30 mg daily) controlled her abdominal symptoms and hypertension. Multiple intrarenal microaneurysms in SLE with APA may be the cause of severe hypertension and elevated serum ARC.

Cytokine and immunogenetic profiles in Japanese patients with adult Still's disease. Association with chronic articular disease.

OBJECTIVE: To determine cytokines and MHC class II alleles in Japanese patients with adult Still's disease (ASD) and clarify the association between those profiles and chronic articular disease. METHODS: Of 35 patients with ASD (13 men, 22 women, mean age at onset 34.0 yr), 17 (49%) had chronic arthritis (>6 months, chronic articular ASD) and 18 (51%) lacked chronic arthritis (systemic ASD). Cytokines and cytokine receptors in sera were measured by ELISA. Correlations of each cytokine with disease activity or C-reactive protein (CRP) were determined. MHC class II alleles were examined by polymerase chain reaction methods. RESULTS: In chronic articular ASD, female gender was more frequent and liver dysfunction and myalgia were rarer than in systemic ASD. In active disease, the white blood cell count was lower, but total IgG was greater in patients with chronic articular ASD than in those with systemic ASD. Tumour necrosis factor (TNF) alpha, soluble TNF receptor 2 and interleukin (IL)-18 were increased in both types of ASD, even in remission. Soluble IL-2 receptors, IL-4 and IL-18 levels were correlated with disease activity or CRP value only in chronic articular ASD. Interferon gamma and IL-8 remained increased only in chronic articular ASD, even when disease activity, including IL-6 and CRP, was low. DRB1*1501 (DR2) and DRB1*1201 (DR5) alleles were more frequent in chronic articular than in systemic ASD, whereas DQB1*0602 (DQ1) was frequently observed in both types of ASD. CONCLUSION: The present study suggests that ASD with chronic articular disease has distinct clinical, cytokine and immunogenetic profiles.

Expression and purification of recombinant rat eosinophil-associated ribonucleases, homologues of human eosinophil cationic protein and eosinophil-derived neurotoxin, and their characterization.

BACKGROUND: Human eosinophils contain two eosinophil ribonucleases, eosinophil cationic protein (ECP) and eosinophil-derived neurotoxin (EDN). In rats, 8 homologues of human ECP and EDN have been identified. To clarify the biological activity of rat eosinophil ribonucleases, we cloned rat eosinophil-associated ribonuclease (EAR)-1/rat ribonuclease 7 and rat EAR-2/rat ribonuclease 4, and produced recombinant rat pre-EAR-1 and pre-EAR-2 in a bacterial expression system. METHODS: As we have already cloned the complete nucleotide sequence for rat EAR-1, we determined that for rat EAR-2 cDNA by the rapid amplification of cDNA ends procedure. Recombinant rat pre-EAR-1 and pre-EAR-2 were expressed in Escherichia coli as N-terminal 6 x histidine-tagged proteins, isolated from the insoluble fraction of the cell lysate and purified by a single-step method using an Ni-NTA resin column after solubilization with a 6 M guanidine solution. RESULTS: The deduced amino acid sequence revealed that the molecular weight of EAR-2 containing the signal peptide is 17.3 kD and the isoelectric point is 8.59. The homology in amino acid sequence between rat pre-EAR-2, and human pre-ECP and human pre-EDN is 51 and 53%, respectively. The purified and refolded recombinant rat pre-EAR-1 and pre-EAR-2 showed bactericidal activity against E. coli and Staphylococcus aureus. CONCLUSIONS: These findings suggest that rat EAR-1 and EAR-2 act as host defense factors against bacterial infection in rats.

Functional anatomy of musical perception in musicians.

The present study used functional magnetic resonance to examine the cerebral activity pattern associated with musical perception in musicians and non-musicians. Musicians showed left dominant secondary auditory areas in the temporal cortex and the left posterior dorsolateral prefrontal cortex during a passive music listening task, whereas non-musicians demonstrated right dominant secondary auditory areas during the same task. A significant difference in the degree of activation between musicians and non-musicians was noted in the bilateral planum temporale and the left posterior dorsolateral prefrontal cortex. The degree of activation of the left planum temporale correlated well with the age at which the person had begun musical training. Furthermore, the degree of activation in the left posterior dorsolateral prefrontal cortex and the left planum temporale correlated significantly with absolute pitch ability. The results indicated distinct neural activity in the auditory association areas and the prefrontal cortex of trained musicians. We suggest that such activity is associated with absolute pitch ability and the use-dependent functional reorganization produced by the early commencement of long-term training.

Human anti-asparaginyl-tRNA synthetase autoantibodies (anti-KS) increase the affinity of the enzyme for its tRNA substrate.

Autoantibodies directed against specific human aminoacyl-tRNA synthetases have been associated with a clinical picture including myositis, arthritis, interstitial lung disease and other features that has been referred to as the "anti-synthetase syndrome". Anti-asparaginyl-tRNA synthetase autoantibodies (anti-KS), the most recently described anti-synthetase autoantibodies, are directed against human cytosolic asparaginyl-tRNA synthetase and neutralize specifically its activity. Here we show that these antibodies recognize two epitopes on the human enzyme, an N-terminal epitope reactive in immunoblot experiments and a heat-labile epitope in the catalytic domain. In contrast to the well studied anti-Jo-1 autoantibodies anti-KS when bound to the synthetase increase the affinity of the synthetase for its tRNA substrate and prevent aminoacylation without interfering with the amino acid activation step.

Myositis and interstitial lung disease associated with autoantibody to a transfer RNA-related protein Wa.

We describe 2 patients with myositis and interstitial lung disease with the autoantibody to Wa antigen, a 48-kDa transfer RNA-related protein. In contrast to the previous description of anti-Wa antibody, our patients lacked systemic sclerosis-related features, but had clinical features consistent with those associated with antibodies to aminoacyl-transfer RNA synthetases. The difference in clinical presentation between our patients and patients with systemic sclerosis may be explained by recognition of different epitopes on the Wa antigen.

Interstitial lung disease in polymyositis and dermatomyositis.

Interstitial lung disease (ILD) is common in patients with polymyositis (PM) and dermatomyositis (DM), and is a major cause of morbidity. Although its cause is unknown, it is known to be closely associated with autoimmune disorders. Its manifestation has been found to be quite heterogeneous, as demonstrated by the differences among PM/DM patients in their immunologic profiles and histopathologic findings, which suggest variations in immunopathogenetic mechanisms. We review the clinicopathologic and immunologic findings in ILD associated with PM/DM, and discuss recent advances in classification, autoantibodies, and treatment. The most critical issues are to clarify the immunopathogenesis of severe forms of ILD, such as rapidly progressive ILD associated with amyopathic DM, and to establish the most appropriate therapy.