Complement profile in microscopic polyangiitis and granulomatosis with polyangiitis: analysis using sera from a nationwide prospective cohort study.

OBJECTIVE: The complement cascade, especially the alternative pathway of complement, has been shown in basic research to be associated with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). We aimed to elucidate relationships between serum complement components and clinical characteristics in AAV. METHOD: In a nationwide prospective cohort study (RemIT-JAV-RPGN), we measured the serum levels of C1q, C2, C3, C3b/iC3b, C4, C4b, C5, C5a, C9, factor B, factor D, factor H, factor I, mannose-binding lectin, and properdin in 52 patients with microscopic polyangiitis (MPA) and 39 patients with granulomatosis with polyangiitis (GPA). RESULTS: The properdin level of MPA and GPA was significantly lower than that of healthy donors. The properdin level was negatively correlated with the Birmingham Vasculitis Activity Score (BVAS) (ρ = -0.2148, p = 0.0409). The factor D level at 6 months was significantly positively correlated with the Vasculitis Damage Index (VDI) at 6, 12, and 24 months (ρ = 0.4207, 0.4132, and 0.3115, respectively). Patients with a higher ratio of C5a to C5 had higher neutrophil percentage and serum immunoglobulin G levels, and significantly lower creatinine levels. Cluster analysis divided the MPA and GPA patients into three subgroups. A principal component (PC) analysis aggregated 15 types of complements into alternative pathway-related PC 1 and complement classical pathway and common pathway-related PC 2. CONCLUSIONS: The serum levels of properdin and factor D were correlated with the BVAS and the VDI in MPA and GPA, respectively. Our analyses suggested the pathological heterogeneity of MPA and GPA from the aspect of complement components.

Longitudinal associations of active renal disease with irreversible organ damage accrual in systemic lupus erythematosus.

OBJECTIVE: To examine longitudinal associations of active lupus nephritis with organ damage accrual in patients with systemic lupus erythematosus (SLE). METHODS: This study was performed using data from a large multinational prospective cohort. Active lupus nephritis at any visit was defined by the presence of urinary casts, proteinuria, haematuria or pyuria, as indicated by the cut-offs in the SLE Disease Activity Index (SLEDAI)-2K, collected at each visit. Organ damage accrual was defined as a change of SLICC-ACR Damage Index (SDI) score >0 units between baseline and final annual visits. Renal damage accrual was defined if there was new damage recorded in renal SDI domains (estimated glomerular filtration rate <50%/proteinuria >3.5 g per 24 h/end-stage kidney disease). Time-dependent hazard regression analyses were used to examine the associations between active lupus nephritis and damage accrual. RESULTS: Patients (N = 1735) were studied during 12,717 visits for a median (inter-quartile range) follow-up period of 795 (532, 1087) days. Forty per cent of patients had evidence of active lupus nephritis at least once during the study period, and active lupus nephritis was observed in 3030 (24%) visits. Forty-eight per cent of patients had organ damage at baseline and 14% accrued organ damage. Patients with active lupus nephritis were 52% more likely to accrue any organ damage compared with those without active lupus nephritis (adjusted hazard ratio = 1.52 (95% confidence interval (CI): 1.16, 1.97), p < 0.02). Active lupus nephritis was strongly associated with damage accrual in renal but not in non-renal organ domains (hazard ratios = 13.0 (95% CI: 6.58, 25.5) p < 0.001 and 0.96 (95% CI: 0.69, 1.32) p = 0.8, respectively). There was no effect of ethnicity on renal damage accrual, but Asian ethnicity was significantly associated with reduced non-renal damage accrual. CONCLUSION: Active lupus nephritis measured using the SLEDAI-2K domain cut-offs is associated with renal, but not non-renal, damage accrual in SLE.

A Pharmacokinetic/Pharmacodynamic Drug-Drug Interaction Study of Tofogliflozin (a New SGLT2 Inhibitor) and Selected Anti-Type 2 Diabetes Mellitus Drugs.

OBJECTIVE: Tofogliflozin is an oral hypoglycemic agent with a novel mechanism of action that reduces blood glucose levels by promoting glucose excretion in urine, achieved by selectively inhibiting sodium-glucose co-transporter 2 (SGLT2). We evaluated the effects of several selected anti-type 2 diabetes mellitus (T2DM) drugs-glimepiride, metformin, sitagliptin, pioglitazone, miglitol, nateglinide, and voglibose-on the pharmacokinetics and pharmacodynamics of tofogliflozin, and the effects of tofogliflozin on the pharmacokinetics of these anti-T2DM drugs in healthy male volunteers. METHODS: A single dose of either tofogliflozin alone, one of the anti-T2DM drugs alone, or co-administration of tofogliflozin and the anti-T2DM drug was administered to 108 healthy men. Cmax, AUCinf, and cumulative urine glucose excretion after co-administration of tofogliflozin and each of the anti-T2DM drugs was evaluated relative to the values of those parameters after administration of each drug alone. RESULTS: None of the anti-T2DM drugs had any effect on tofogliflozin exposure. Tofogliflozin had no or little effect on the exposure of any anti-T2DM drug. No anti-T2DM drug had any major effect on the cumulative urine glucose excretion induced by tofogliflozin. There were no safety concerns evident after administration of any drug alone or in co-administration. CONCLUSIONS: Neither the pharmacokinetics nor the pharmacodynamics of tofogliflozin was affected by any of the anti-T2DM drugs evaluated in this study, nor was the pharmacokinetics of any of the anti-T2DM drugs affected by tofogliflozin in healthy male volunteers.

Psychological distress in corticosteroid-naive patients with systemic lupus erythematosus: A prospective cross-sectional study.

OBJECTIVE: Psychological distress, such as depression and anxiety, has been intensively studied in patients with systemic lupus erythematosus (SLE). However, those studies have mostly included patients who were treated with corticosteroids, which might themselves induce mood disturbances. We investigated psychological distress in corticosteroid-naive patients with SLE who did not exhibit any overt neuropsychiatric manifestations. METHODS: Forty-three SLE in-patients with no current or past abnormal neuropsychiatric history participated in the study. Patients and 30 healthy control subjects with similar demographic and personality characteristics were administered a comprehensive battery of psychological/neuropsychological tests. The Profile of Mood States (POMS) was used to assess depression and anxiety. Results of clinical, laboratory, and neurological tests were compared with regard to their presence. RESULTS: Prevalence of depression was higher in patients (n = 11, 25.6%) than in controls (n = 2, 6.7%; p = 0.035), although prevalence of anxiety did not differ across groups (patients: 34.9%, n = 15; controls: 16.7%, n = 5; p = 0.147). Using multiple logistic regression analysis, we identified avoidance coping methods (OR, 1.3; 95% CI 1.030-1.644; p = 0.027) as an independent risk factor for depression. CONCLUSION: Our results indicate that depression presents more frequently in corticosteroid-naive patients with early-stage, active SLE than in the normal population, but anxiety does not. Depression may be related to psychological reactions to suffering from the disease.

Association of IRF5 polymorphism with MPO-ANCA-positive vasculitis in a Japanese population.

Interferon regulatory factor 5 (IRF5) and signal transducer and activator of transcription 4 (STAT4) are shared susceptibility genes for various autoimmune diseases. In this study, we investigated whether these genes also contribute to susceptibility to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in a Japanese population. A case-control study was carried out on IRF5 rs10954213 and STAT4 rs7574865 in 232 Japanese myeloperoxidase (MPO)-ANCA-positive AAV patients, including 177 microscopic polyangiitis and 710 healthy controls. IRF5 rs10954213G was significantly increased in MPO-ANCA-positive AAV (additive model, P=0.023, odds ratio=1.27, 95% confidence interval=1.03-1.57). The risk allele was previously shown to be associated with lower mRNA level of IRF5. On the other hand, significant association of STAT4 rs7574865T with AAV was not detected. These observations suggested that IRF5 may contribute to susceptibility to MPO-ANCA-positive AAV in a Japanese population.

Postmarketing surveillance of the safety profile of infliximab in 5000 Japanese patients with rheumatoid arthritis.

OBJECTIVES: A large-scale postmarketing surveillance (PMS) study was carried out to determine the safety profile of infliximab in Japanese patients with rheumatoid arthritis (RA). METHODS: The PMS study was performed for all patients with RA who were treated with infliximab. They were consecutively registered in the PMS study at the initiation of infliximab treatment and were prospectively monitored with all adverse events noted for a period of 6 months. All case reports, which include safety-related events, were collected monthly. RESULTS: Adverse drug reactions (ADRs) were assessed for 6 months in 5000 patients who were consecutively enrolled in the PMS study. The incidence rates of total and serious ADRs were 28.0% and 6.2%, respectively. "Infections" or "respiratory disorders" were most commonly observed among serious ADRs. Bacterial pneumonia developed in 2.2%, tuberculosis in 0.3%, suspected Pneumocystis jiroveci pneumonia (PCP) in 0.4% and interstitial pneumonitis in 0.5%. Bacterial pneumonia (for which individuals of male gender, of older age and those with advanced rheumatoid arthritis and comorbid respiratory disease were most at risk) began to develop immediately after the start of treatment, while tuberculosis, PCP and interstitial pneumonitis developed about 1 month later. Serious infusion reactions were observed in 0.5% and were more likely to occur in patients who had participated in previous clinical trials of infliximab. CONCLUSION: This postmarketing surveillance study of patients treated with infliximab showed that infliximab in combination with low-dose MTX was well tolerated in Japanese patients with active RA.

Serum nitric oxide (NO) levels in systemic sclerosis patients: correlation between NO levels and clinical features.

Vascular damage in systemic sclerosis (SSc) may be a factor in the abnormal regulation of several vasoactive agents. It has been well confirmed that plasma endothelin-1, as a vasoconstrictive factor, is elevated in patients with SSc. However, it is still controversial whether the levels of serum nitric oxide (NO), a strong vasodilator, are increased or decreased in SSc patients compared to healthy donors. In this study, we measured the levels of serum NO metabolites in SSc patients and determined the contribution of the excessive production of NO synthase (NOS)-2 by skin fibroblasts to NO synthesis. Serum NO levels of 45 patients with SSc were significantly higher than those of 20 healthy volunteers. In addition, some clinical features of SSc (the extent of skin fibrosis, short disease duration, and the complication of active fibrosing alveolitis) were all correlated positively with the levels of NO metabolites in SSc patients. To evaluate the levels of NOS-2 produced by skin fibroblasts, skin fibroblast cultures were established from SSc patients and healthy volunteers. Reverse transcription-polymerase chain reaction indicated that NOS-2 mRNA was spontaneously expressed in cultured fibroblasts derived from SSc patients, but not in those derived from healthy normal controls. Immunohistochemical staining also showed that NOS-2 proteins were detected in SSc fibroblasts but not in normal fibroblasts. The production of NO by cultured fibroblasts was visualized directly by a reagent (DAF-2 DA) used for the fluorescent detection of NO. Cultured SSc fibroblasts were capable of NO synthesis in culture media containing L-arginine, whereas normal fibroblasts (with no expression of NOS-2) did not synthesize detectable NO. These observations indicate that NO production is increased markedly in early-stage diffuse cutaneous SSc patients with active fibrosing alveolitis, and that constitutive NOS-2 expression in SSc fibroblasts may contribute to increased NO production.

Association between adult-onset Still's disease and interleukin-18 gene polymorphisms.

Recently, we reported that serum concentration of IL-18 is strikingly high in patients with adult-onset Still's disease (AOSD). The aim of the present study was to screen for genetic polymorphisms in the human IL-18 (hIL-18) gene and to determine the association of polymorphisms with susceptibility to AOSD. We investigated the 6.7 kb region upstream of exon 2 of hIL-18 gene, in which a promoter activity had been reported. Sixteen AOSD patients, 144 rheumatoid arthritis (RA) patients and 92 healthy control individuals were studied. We found seven single nucleotide polymorphisms and a single 9 bp insertion which were frequently present in the AOSD patients. Three haplotypes including a unique combination of these polymorphisms were also determined. Of them, haplotype S01 contained all eight of these polymorphisms. The frequency of individuals carrying a diplotype configuration, ie a combination of two haplotypes, of S01/S01 was significantly higher in the AOSD patients than in the healthy controls (P=0.00059, Fischer's exact probability test, odds ratio [OR]=7.81, 95% confidence interval [95% CI]=2.48-24.65) and the RA patients (P=0.015, Fischer's exact probability test, OR=4.0, 95% CI=1.39-11.54). We therefore conclude that possession of the diplotype configuration of S01/S01 is a major genetic risk factor for susceptibility to AOSD.

A hallmark of active class switch recombination: transcripts directed by I promoters on looped-out circular DNAs.

To specify when and where Ig class switch recombination (CSR) takes place, a good molecular marker closely associated with active CSR is required. CSR is accompanied by deletion of circular DNA from the Ig heavy chain locus. The circular DNA contains a DNA segment between Smu and a target S region including its I promoter, which is driven by specific cytokine stimulation before CSR. We found that the specific I promoter is still active in looped-out circular DNA and directs production of I-Cmu transcripts termed "circle transcripts." Reverse transcription-PCR demonstrated transient induction of specific circle transcripts upon CSR in a murine lymphoma cell line, CH12F3-2A, as well as spleen B cells. Production of the circle transcripts appeared to depend on expression of activation-induced cytidine deaminase (AID), an essential factor for CSR. A comparison of kinetics between circle transcripts and circular DNA showed more rapid disappearance of circle transcripts. Thus, circle transcripts may serve as a hallmark for active CSR in vitro and in vivo.

[A case of recurrent hemophagocytic syndrome complicated with systemic sclerosis: relationship between disease activity and serum level of IL-18].

Hemophagocytic syndrome (HPS) is characterized by the activation of the mononuclear phagocytic system with prominent hemophagocytosis in the bone marrow and reticuloendothelial systems, and its occurrence is usually associated with variable disorders such as viral infections and malignant lymphoma. Recently, it was reported that HPS also occurred in association with underlying connective tissue disease, especially systemic lupus erythematosus. We report here a case of recurrent HPS complicated with systemic sclerosis. A 32-year-old woman had been diagnosed as systemic sclerosis since 1994. She was admitted due to unknown high fever and severe pancytopenia in 1997, and the diagnosis of HPS was determined because of hemophagocytosis in bone marrow and hyperferritinemia. Her symptoms were improved by immunosuppressive therapies including steroid pulse therapy and oral prednisolone (60 mg/day). She was followed by the treatment of oral prednisolone which was gradually tapered in our out-patient clinic. In August of 1999 high fever and severe anemia were recurred, and she was admitted again to our hospital because of the diagnosis as recurrent HPS. She had been treated with 40 mg/day of oral prednisolone and fever was immediately disappeared and hemoglobin was gradually increased. HPS is considered to be a rare complication with systemic sclerosis, and the etiology has been unknown. IL-18 is a novel cytokine which is a potent inducer of interferon-gamma, and its properties may be a proinflammatory regulation and activation of monocyte/macrophage and histiocyte through the expression of interferon-gamma. Therefore, the significance of IL-18 in the pathophysiology of HPS was recently reported. In this case, we investigated the significance of IL-18 and revealed the levels of serum IL-18 were well correlated with disease activity of HPS.

Tumor necrosis factor-alpha (TNF-alpha) converting enzyme contributes to production of TNF-alpha in synovial tissues from patients with rheumatoid arthritis.

OBJECTIVE: Expression and function of tumor necrosis factor-alpha (TNF-alpha) converting enzyme (TACE) in synovia of patients with rheumatoid arthritis (RA) were examined to investigate posttranslational regulation of TNF-alpha production by TACE in RA. METHODS: Expression of TACE protein was evaluated by immunohistochemistry. Cytokines and soluble cytokine receptors were measured by ELISA. TACE mRNA was detected by RT-PCR. The enzymatic activity of TACE was measured using TACE-specific fluorogenic substrate. RESULTS: Expression of TACE at protein level in synovial tissue (ST) of patients with RA was significantly stronger than that of patients with osteoarthritis (OA). In RA, TACE was mainly expressed in CD68+ macrophage-like synovial cells. ST from 9 of 9 RA and 3 of 8 OA patients expressed TACE mRNA. RA ST cells possessed significantly higher TACE-like enzymatic activity than OA ST. A synthetic TACE inhibitor significantly reduced the release of TNF-alpha and p75 TNF receptor from RA ST cells. CONCLUSION: TACE is an important regulator of the secretion of TNF-alpha from synovia of patients with RA.

Mature form of interleukin 18 is expressed in rheumatoid arthritis synovial tissue and contributes to interferon-gamma production by synovial T cells.

OBJECTIVE: To investigate the expression and function of interleukin 18 (IL-18) in synovial tissue (ST) of patients with rheumatoid arthritis (RA). METHODS: The localization of IL-18 in ST was analyzed by immunohistochemistry. IL-18 and IL-18 receptor (IL-18R) mRNA were detected by RT-PCR. Expression of IL-18 at the protein level was analyzed by Western blotting. Cytokines in culture supernatants were measured by ELISA. RESULTS: From immunohistochemical analysis, IL-18-producing cells were localized in the lining layer and sublining region of RA ST. Most of them coexpressed CD68 antigen. In ST from patients with osteoarthritis (OA), IL-18-producing cells were localized only in the sublining region and the numbers of these cells were small. From RT-PCR, RA ST expressed mRNA of IL-18, as well as alpha- and beta-chains of IL-18R. OA ST did not express or very weakly expressed mRNA of alpha- and beta-chains of IL-18R. ST from RA patients produced significantly larger amounts of IL-18 in vitro than OA ST. Western blotting revealed that RA ST expressed mature IL-18 more abundantly than OA ST. IL-12 alone stimulates interferon-gamma (IFN-gamma) production by RA synovial tissue cells, but IL-18 alone could not. In the presence of IL-12, however, IL-18 could synergistically stimulate IFN-gamma production by RA synovial tissue cells. OA synovial tissue cells responded to neither IL-12 nor IL-12 + IL-18. IL-18 showed synergistic effects with IL-12 on promoting the ability of synovial T cells from RA patients to produce IFN-gamma. CONCLUSION: These findings suggest that mature IL-18 is expressed in RA synovia and contributes to the production of IFN-gamma by infiltrating T cells.

Amino acids in the N-terminal region regulate the photocycle of photoactive yellow protein.

The spectroscopic properties of photoactive yellow protein (PYP) partially digested by chymotrypsin were studied. Chymotrypsin yielded three major products that were yellow but distinguishable by SDS-PAGE. They were readily separated by DEAE-Sepharose column chromatography. Protein sequencing and mass spectrometry demonstrated that chymotrypsin cleaved the N-terminal 6, 15, or 23 amino acids (T6, T15, and T23). The blue-shifts of the absorption maxima and the increases in the apparent pK(a) of the chromophores relative to those of intact PYP were less than 4 nm and 0.2, respectively. The absorption spectra of the near-UV intermediates produced from T6, T15, and T23 were identical to that of intact PYP, but with lifetimes that were 140, 2,300, and 4,500 times longer, respectively. These observations suggest that the recovery of the dark state of PYP from the near-UV intermediate is accelerated by the N-terminal region, and that this region acts as a regulatory factor for the photocycle of PYP.

Guillain-Barré syndrome accompanied by central nervous system lupus in a patient with juvenile rheumatoid arthritis.

Abstract We describe a 17-year-old female with juvenile rheumatoid arthritis accompanied by Guillain-Barré syndrome (GBS) during the course of central nervous system (CNS) lupus. She initially developed CNS lupus, including headache and convulsion. A high-signal area in a magnetic resonance scan of her brain with T2-weighted images was noted, and her cerebrospinal fluid exhibited increased levels of IgG and interleukin-6. Eighteen days after the onset of CNS lupus, polyneuropathy in the lower extremities developed, and a diagnosis of GBS was made. No obvious preceding infections in the upper respiratory or gastrointestinal systems were noted before the onset of GBS, indicating that GBS might be part of the symptoms of CNS lupus.

Antiphospholipid syndrome with complete abdominal aorta occlusion and chondritis.

Abstract We report a case of a 42-year-old man with antiphospholipid syndrome (APS) with chondritis. He presented with preceding insidious progressive occlusion of the bilateral common iliac arteries extending to the lower two-thirds of the abdominal aorta. Active thrombotic events developed concurrent with the onset of chondritis, and resulted in massive thromboses in multiple organs and renal dysfunction. Both conditions responded well to combined intravenous high-dose methylprednisolone and anticoagulation therapy. The inflammatory component of his disease may have played a major role in the pathogenesis of thrombosis given the concurrent active inflammation from his chondritis.

Immune thrombocytopenic purpura associated with rheumatoid arthritis - a report of five cases and review of the literature.

Abstract Immune thrombocytopenic purpura (ITP) associated with rheumatoid arthritis (RA) is relatively rare. We describe five cases of RA with ITP. In all five patients, platelet counts were low, platelet-associated IgG levels were elevated, and bone marrow aspiration showed megakaryocytosis. Glucocorticoid therapy was effective in three cases, but the other two cases required immunosuppressants or intravenous γ-globulin in addition to glucocorticoid. We review the reported cases of RA with ITP and discuss the pathophysiology and differential diagnosis of thrombocytopenia in RA.

[A case of Sjögren's syndrome and systemic sclerosis complicated with acute pancreatitis].

We report a case of Sjögren's syndrome (SS) and systemic sclerosis (SSc) complicated with acute pancreatitis. A 51-year-old woman had been diagnosed as SS in 1973. She noticed Raynaud's phenomenon in 1977. In 1988, interstitial pneumonia (IP) was pointed out and she was treated with methylprednisolone (mPSL) pulse therapy. Prednisolone (PSL) was gradually tapered to 3-5 mg daily and she visited our outpatient clinic in 1995. On her first admission to our hospital in 1996, she showed xerostomia, keratoconjunctivitis sicca, sclerotic skin changes of her distal extremities and face, thickening of her sublinguinal frenulum, and regurgitative esophagitis. She was positive with anti-SS-A and SS-B antibodies. She was diagnosed as SS and SSc. Radiographic and laboratory data also established the diagnosis of inactive IP, renal tubular acidosis (RTA) and chronic renal failure (CRF). In April 30th 1997, she was admitted to our hospital again with complaints of dyspnea, dysesthesia, epigastralgia and petechia. Active IP and mononeuritis multiplex were diagnosed, and petechia was considered to be associated with vasculopathy. Her serum amylase level was 891 mU/ml on admission and spontaneously increased to 2440 mU/ml on May 12th along with increase of fibrinogen degradation product, D-dimer and alpha 2 plasmin-plasmin inhibitor complex levels. Ultrasonography depicted swelling of her pancreatic head and the diagnosis of acute pancreatitis was made. She was treated with protease inhibitors and intravenous hyperalimentation for acute pancreatitis. mPSL pulse therapy (500 mg/day for 3 days) was instituted for IP and mononeuritis multiplex on May 22, followed by 50 mg of daily PSL. While IP and mononeuritis multiplex gradually improved by the high-dose steroid therapy, serum amylase level raised to more than 4293 mU/ml, suggesting the modification of pancreatitis by the treatment with steroid. Since she did not respond to the conservative therapy for acute pancreatitis, she was treated with plasmapheresis, which turned out to be very effective. However, she was suffered from fungal pneumonia and died of respiratory failure. As far as we know, only three cases of SS with acute pancreatitis have been reported so far. The immunopathological mechanisms of development of acute pancreatitis in our case, especially focusing on the significance of microvasculopathy and hypercoagulability, were discussed.