Published papers

Purpose: To investigate the distribution and expression of aquaporin 5 (AQP5) and its C-terminal binding protein in the apical membrane of the lacrimal glands (LGs) in a mouse model for Sjogren's syndrome (SS). Methods: The LGs of NOD mice (mouse model for SS) and ICR mice (normal control) were homogenized and delivered into the affinity columns bound to synthetic AQP5 C-terminal peptide. The eluates were analyzed by electrophoresis and liquid chromatography mass spectrometry/mass spectrometry (LC-MS/MS) techniques.Results: AQP5 from the NOD mice exhibited the capacity to bind a 21-kDa protein that was lacking in the ICR mice. Instead, ICR mouse expressed a 17-kDa AQP5 binding protein that was absent in LGs of SS. LC-MS/MS analysis revealed these respective proteins to be major urinary protein 4 (MUP4) and prolactin-inducible protein (PIP). The treatment of ICR mice with antisense PIP oligonucleotides decreased immunostaining of AQP5 in the apical membrane. Conclusions: These observations suggest that the binding of PIP to the C-terminal portion of AQP5 may cause AQP5 to be transported to the apical membrane of LGs. Correction of the aberrant binding of PIP to the AQP5 C-terminus could normalize AQP5 trafficking to the apical membrane, leading to a treatment for patients with SS. Copyright © Informa Healthcare USA, Inc.

Objectives. We monitored the mRNA expression profiles of peripheral blood cells during treatment with a TNF-α inhibitor, infliximab, in patients with RA. Using a DNA microarray analysis, we demonstrated a unique set of genes, with distinct baseline and post-treatment changes in expression between responders and non-responders to infliximab treatment. Methods. Using a customized low-density cDNA microarray with 747 genes and a reliable data collection system, we monitored the mRNA expression profiles of whole blood cells from 18 RA patients before and after the infusion of infliximab for up to 22 weeks. The clinical response to treatment with infliximab was determined using the ACR response criteria, the disease activity score of 28 joints (DAS28), and individual clinical parameters. The patients were classified as responders or non-responders based on their ACR50% response at 22 weeks. Results. Approximately 15% of the total genes were found to exhibit a >1.5-fold change, compared with their reference values, at one or more time points during the 22 weeks of infliximab therapy. The expression of inflammatory genes, such as IFN-related genes, was strongly correlated with the serum level of CRP and the DAS28. The increased expression of inflammatory genes in responders was normalized within 2 weeks and then remained at a normal level during the treatment period. In contrast, in the non-responders, the elevated expression at baseline, although it was significantly decreased at 2 weeks, returned to the baseline level after 14 weeks. In addition to inflammatory genes, we identified several groups of genes with distinct differences in expression between the responders and non-responders. Conclusions. Our results suggest that a customized low-density microarray is useful for monitoring mRNA expression profiles in peripheral blood cells, enabling us to identify a unique set of genes with differentially regulated expressions in responders and non-responders to a TNF inhibitor among patients with RA. © The Author 2008. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved.

We here report the case of a young Japanese woman diagnosed with chronic active Epstein-Barr virus (EBV) infection. Intensive therapy with the CHOP regimen was partially able to control virus expansion, but various central nervous system symptoms appeared and gradually progressed. EBV-encoded RNA, detected using in situ hybridization, disclosed the presence of EBV in liver and bone marrow tissue, and real-time PCR revealed the presence of EBV in the cerebrospinal fluid (CSF) and serum. CD3+CD4+CD8-CD56- T-cell expansion in the peripheral blood (PB) and CSF was also observed. Atrophic brain changes were progressive, and the patient died of central nervous system disturbance and pulmonary hemorrhage a year after diagnosis. Autopsy revealed that EBV-infected T lymphocytes with a phenotype similar to those seen in PB and CSF had infiltrated multiple organs: the lymph nodes, bone marrow, endocardium, pericardium, myocardium, spleen, liver, and spinal cord. There have been few previous reports of severe degenerative changes in the myocardium, liver, and spinal cord in patients with EBV infection. Although EBV occasionally infiltrates the central nervous system and brain, atrophic changes mediated by EBV are rare. The autopsy results of this case suggest the possibility of EBV-mediated, severe degenerative changes in multiple organs. © 2008 The Japanese Society of Hematology.

Biologics targeting TNF have brought about a paradigm shift in the treatment of rheumatoid arthritis (RA) and infliximab, anti-TNF-α chimeric monoclonal antibody, was marketed in 2003 in Japan. We previously reported on the RECONFIRM study, a retrospective clinical study on the efficacy of infliximab therapy in a RA management group in Japan, where we evaluated the clinical response after 22 weeks of the therapy in 258 patients. The study reported here was aimed at reconfirming the clinical efficacy of the infliximab therapy and demographic factors related to the efficacy over a 54-week study period in 410 RA patients in the same study group. Infliximab was infused according to the domestically approved method, and the clinical response was evaluated following 54 weeks of infliximab therapy using the European League Against Rheumatism (EULAR) response criteria. Disease activity was assessed by DAS28-CRP (Disease Activity Score including a 28-joint count/C-reactive protein). Infliximab was discontinued in 24.4% of the 410 patients at 54 weeks and 9.3% and 8.1% discontinued the therapy due to adverse events and inefficiency, respectively. Average DAS28-CRP decreased from 5.5 at week 0 to 3.1 at week 54 after the therapy. Patients in remission and those showing low-, moderate-, and high-disease activity changed from 0.0, 1.0, 9.0 and 90.0%, respectively, at the start of the study to 27.6, 11.7, 34.4 and 26.3%, respectively, at week 54. Younger age, RF-negativity and low scores of DAS28-CRP showed significant correlations with remission at week 54. EULAR response criteria - good, moderate, and no response to infliximab - were 37.0, 41.7 and 21.2%, respectively. In conclusion, we reconfirmed the clinical efficacy of infliximab and demographic factors related to the efficacy over a 54-week study period in 410 Japanese patients with RA using DAS28-CRP and EULAR response criteria. © Japan College of Rheumatology 2008.

We have demonstrated that T-cell receptor ζ (ζ) mRNA with a 562-bp deleted alternatively spliced 3′-untranslated region (3′UTR) observed in T cells of patients with systemic lupus erythematosus (SLE) can lead to a reduction in ζ and TCR/CD3 (J. Immunol., 2003 & 2005). To determine the region in ζ mRNA 3′UTR for the regulation of ζ, ζ mRNA with 3′UTR truncations ligated into pDON-AI was used to infect murine T-cell hybridoma MA5.8 cells, which do not contain ζ. As a Western blot analysis demonstrated the importance of the regions from +871 to +950, containing conservative sequence 1 (CS1), and +1070 to +1136, containing CS2, for the production of ζ, we constructed MA5.8 mutants carrying ζ mRNA 3′UTR with deletions of these regions (ΔCS1 and ΔCS2 mutants). Western blot and FACS analyses showed significant reduction in the cell surface ζ and TCR/CD3 in both these mutants, and IL-2 production was decreased, compared with MA5.8 cells transfected with wild-type ζ mRNA. Furthermore, real-time PCR demonstrated the instability of ζ mRNA with 3′UTR deletions in these MA5.8 mutants. In conclusion, CS1 and CS2 may be responsible for the regulation of ζ and TCR/CD3 through the stability of ζ mRNA in SLE T cells. © 2007 Elsevier Inc. All rights reserved.

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.

Application of biological agents targeting tumor necrosis factor-α (TNF-α) caused a paradigm shift in the treatment of rheumatoid arthritis (RA). The introduction of infliximab in 2003 and etanercept in 2005 in Japan had a significant impact on both Japanese rheumatologists and RA patients, although serious adverse effects such as bacterial pneumonia, tuberculosis and Pneumocystis jiroveci pneumonia are significant concerns. Based on the data from post-marketing surveillance in Japan and accumulating evidence worldwide, the Internal Medicine Rheumatology Study Group of the Ministry of Health, Labor and Welfare (MHLW), Japan, has updated the guidelines for the use of anti-TNF-α agents for RA, which were subsequently approved by the Board of Japan College of Rheumatology (JCR). In the present revised guidelines, we combined the guidelines for use of each of infliximab and etanercept together with some modifications and precautions, paying special attention to serious adverse reactions. Although it is still controversial whether the use of TNF-α blocking agents per se increases the risk of infection or not, bacterial pneumonia, regardless of the pathogens, is the most frequent complications in RA. The risk factors associated with pneumonia identified in the post-marketing surveillance of infliximab in Japan are presented in this guideline. The diagnostic algorithm is also designed for early diagnosis and treatment of pulmonary lesions seen during the treatment of biological agents. Preventive measures and precautions against tuberculosis, another frequent and significant complication in Japan, are also described. Furthermore, risk factors for developing Pneumocystis pneumonia, which uniquely occurs at 30- to 50-fold frequency under TNF-α blockade therapy in Japan, are described here and its preventive measures are discussed. It is stressed that secondary-care rheumatologists should be better familiarized with the proper use of TNF-α blocking agents and be alert to any adverse events for a better management of RA patients. © Japan College of Rheumatology 2007.

Aim: Serum levels of C-reactive protein (CRP) and matrix metalloproteinase-3 (MMP-3) are used as indicators of the activity of rheumatoid arthritis (RA). The aim of this study was to characterize the clinical features of patients showing exclusive elevation of either serum CRP or MMP-3, and the differences in the time-course of changes between the serum levels of MMP-3 and CRP after initiation of therapy. Methods: A total of 129 RA patients were classified into four groups according to the serum levels of CRP and MMP-3 at the time of enrolment: Negative for both CRP and MMP-3 levels; positive for both; positive for CRP alone (CRP-positive group); and positive for MMP-3 alone (MMP-3-positive group). The analysis included evaluation of the serum CRP and MMP-3 levels, and the Lansbury Articular Index at enrolment and at final observation. Results: In the CRP-positive group (19%), 21% of the patients remained CRP-positive at the final observation; 42% became double-negative, and 31% became double-positive. In contrast, in the MMP-3-positive group (9%), about two-thirds of the patients remained MMP-3-positive at the final observation. The disease duration in the MMP-3-positive group was significantly longer, and the ratio of the number of large swollen joints to the total number of swollen joints was higher as compared with that in the other groups. Furthermore, elevated serum CRP responded faster to disease-modifying antirheumatic drug therapy than elevated serum MMP-3. Conclusions: Serum CRP is a better predictor of the response to treatment than serum MMP-3, which is associated to a greater extent with large joint involvement. © 2007 Asia Pacific League of Associations for Rheumatology.

We have reported that Sjögren's syndrome (SS) patients with enlarged exocrine glands (EEG) formerly referred to as Mikulicz's disease were defective with Fas-ligand (FasL) expression in PBL and lacrimal glands (LGs). To investigate the mechanisms of reduced FasL expression in SS patients with EEG, FasL mRNA expression level was determined using real-time PCR. The FasL gene promoter region (from -1197 to -3) was also amplified using PCR and specific primers. Expression of the FasL mRNA in the LGs and PBLs of three SS patients with EEG was significantly decreased. Direct sequencing revealed a heterozygous point mutation (-259T/C) in the FasL gene promoter region in one SS patient with EEG. A luminescent β-galactosidase (β-gal) reporter assay using a pβgal Enhancer Vector demonstrated that β-gal activity from the vector including the mutant (-259C) FasL (pβgal/mFasL) gene promoter region (735±42) was similar (p = 0.13) to that from a pβgal Enhancer Vector without the gene promoter region (603±66). On the other hand, the β-gal activity was significantly lower (p<0.0001) than that from a vector including the wild-type (-259T) FasL (pbeta;gal/wFasL) (3226±148). In conclusion, the down-regulation of FasL in SS patients with EEG may be due to transcriptional regulation, and the point mutation at -259T/C in the FasL gene promoter region may lead to the down-regulation of FasL mRNA expression and the lymphoproliferative process observed in SS patients with EEG.

Objective: To evaluate the ability of tocilizumab (a humanised anti-IL-6 receptor antibody) monotherapy to inhibit progression of structural joint damage in patients with RA. Methods: In a multi-centre, x ray reader-blinded, randomised, controlled trial, 306 patients with active RA of <5 years' duration were allocated to receive either tocilizumab monotherapy at 8 mg/kg intravenously every 4 weeks or conventional disease-modifying antirheumatic drugs (DMARDs) for 52 weeks. Radiographs of hands and forefeet were scored by the van der Heijde modified Sharp method. Results: Patients had a mean disease duration of 2.3 years and a disease activity score in 28 joints of 6.5 at baseline. Mean total modified Sharp score (TSS) was 29.4, which was very high despite the relatively short disease duration. At week 52, the tocilizumab group showed statistically significantly less radiographic change in TSS (mean 2.3; 95% CI 1.5 to 3.2) than the DMARD group (mean 6.1; 95% CI 4.2 to 8.0; p<0.01). Tocilizumab monotherapy also improved signs and symptoms. The overall incidences of AEs were 89% and 82% (serious AEs: 18% and 13%; serious infections: 7.6% and 4.1%) in the tocilizumab and DMARD groups, respectively. Conclusion: Tocilizumab monotherapy was generally well tolerated and provided radiographic benefit in patients with RA.

Although corticosteroids and immunosuppressants are widely used for the treatments of systemic lupus erythematosus (SLE), safer and more effective therapies are prerequisite. We and others have reported that anti-CD20 antibody rituximab targeting B cells are effective for refractory SLE and, therefore, safety and clinical efficacy of rituximab in SLE was evaluated by a multicenter phase I/II clinical trial. An open-label, multicenter study of 15 patients with active and refractory SLE (total British Isles Lupus Assessment Group [BILAG] score 8 to 17) was conducted. Rituximab was administered to 5 SLE patients as 4 infusions of 500 mg/body every week and to 10 SLE patients as 2 infusions of 1000 mg/body every other week. Assessment of safety, infusion reactions and adverse effects was used as the primary outcome for clinical tolerability and was evaluated by 28 weeks. Rituximab was well tolerated, with most experiencing no significant adverse effects. B cells rapidly reduced in all patients and remained low until 6 months post-treatment. Four patients developed human antichimeric antibodies without affecting efficacy of rituximab. Changes in routine safety laboratory tests clearly related to rituximab were not observed. Nine among 14 evaluable patients achieved the major or partial clinical response of BILAG score and prednisolone dose significantly decreased at the 28 weeks. Rituximab therapy appears to be safe for the treatment of active SLE patients and holds significant therapeutic promise, at least for the majority of patients experiencing profound B-cell depletion. © Japan College of Rheumatology 2007.

We evaluated the efficacy and safety of low-dose cyclosporine A (CsA) in patients with refractory lupus nephritis. Nine patients with systemic lupus erythematosus who had lupus nephritis resistant to previous treatment with glucocorticoids and immunosuppressants other than CsA were enrolled in a prospective, open-label study. All patients initially received 2.5 mg/kg per day of CsA; the dosage was adjusted to reach a blood trough level of 80-150ng/ml. The urinary protein concentration decreased significantly 2 weeks after the initiation of treatment. After 30 weeks of CsA treatment, the mean urinary protein concentration was more than 50% lower than the baseline value, and urinary casts had decreased significantly. There were no significant changes in the levels of serum creatinine, serum anti-double-stranded DNA antibodies, or CH50 during any part of the study. The dose of glucocorticoids was significantly tapered by approximately 50%, without any disease flare. Hypertension developed in one patient, but was controlled with antihypertensive agents. Our results suggest that low-dose CsA therapy is an effective and less toxic alternative to conventional cyclophosphamide therapy for the management of refractory lupus nephritis. © Japan College of Rheumatology 2007.

Objective. Individuals with rheumatoid arthritis (RA) with or without methotrexate (MTX) medication occasionally develop lymphoproliferative disorders (MTX-LPD and non-MTX-LPD, respectively). The hyperimmune state of RA itself or the immunosuppressive state induced by MTX administration might contribute to development of LPD. Our objective was to characterize MTX-LPD in comparison to non-MTX-LPD and sporadic LPD in patients with RA. Methods. We compared MTX-LPD to non-MTX-LPD and sporadic LPD by evaluating 48 cases of MTX-LPD, 28 non-MTX-LPD, and 150 sporadic LPD. Results. Later onset age of LPD and female predominance were evident in patients with RA-LPD compared to sporadic LPD. The interval between the diagnosis of RA and LPD in MTX-LPD (median 132 mo) was significantly shorter than that in non-MTX-LPD (240 mo). The frequency of diffuse large B cell lymphoma (DLBCL) and positive rate of Epstein-Barr virus (EBV) in RA-LPD was significantly higher than in sporadic LPD (57.9% vs 42.7%, 27.6% vs 9.9%, respectively). After withdrawal of MTX, 11 of the MTX-LPD cases showed a spontaneous regression of tumors. The 5-year survival rate in RA-LPD (59.2%) was significantly worse than that in sporadic LPD (74.6%). Conclusion. The majority of cases of RA-LPD show similar clinicopathological characteristics irrespective of MTX medication, except for spontaneous regression of LPD after withdrawal of MTX in MTX-LPD. and a shorter interval between the diagnosis of RA and LPD in MTX-LPD than in non-MTX-LPD. RA-LPD cases showed younger age of onset, female predominance, unfavorable prognosis, and higher frequencies of DLBCL and EBV positivity compared to sporadic LPD.

This study aims to reconfirm the clinical efficacy and related factors of infliximab therapy, the first biological agent introduced to Japanese patients with rheumatoid arthritis (RA). Data of 351 RA patients with infliximab were collected retrospectively from three major centers for management of rheumatic diseases in Japan. Infliximab was infused according to the approved method, and the clinical response was evaluated following 22 weeks of infliximab therapy in 258 patients using the European League Against Rheumatism (EULAR) response criteria. DAS28-CRP (Disease Activity Score including a 28-joint count/C-reactive protein) with a threshold of 4.1 or 2.7 for the high or low disease activity cut-off was also used. A total of 90.3% of patients exhibited high disease activity before infliximab therapy. After 22 weeks of infliximab therapy, the proportions of patients exhibiting high activity, moderate activity, low activity, or in clinical remission were 27.9%, 33.3%, 10.9%, or 27.9%, respectively, thereby indicating good overall efficacy of infliximab therapy. A good or moderate overall response to therapy was achieved in 84.5% of patients. Male sex, rheumatoid factor (RF) negativity, low CRP, lower swollen joint count and a low prednisolone dose were significantly related to the clinical response. Furthermore, male sex, older age, and a high tender joint count had a significant correlation with treatment discontinuation as a result of adverse reactions. In conclusion, we have reconfirmed the effectiveness of infliximab in Japanese patients with RA by using DAS28-CRP and EULAR response criteria. These data will facilitate more efficacious use of this expensive biological agent in the daily practice of rheumatology in Japan. © Japan College of Rheumatology 2007.

Basophils play an important role in allergic inflammation and are pathologically related to hematological disturbances, such as iron deficiency anemia and myeloproliferative disorders; however, they are only rarely encountered in lymphoid malignancies. Here, we report the case of a 33-year-old man with a bulky mass of the small intestine, multiple paraaortic lymphoadenopathy, pleural effusion, and ascites, who was diagnosed as a case of de novo CD5+ diffuse large B cell lymphoma (DLBCL). This patient showed a marked elevation of the basophil count in the peripheral blood, which appeared to run in parallel with the tumor burden. High dose chemotherapy followed by autologous peripheral blood cell transplantation yielded complete remission, and the patient has remained disease free for 5 years. To the best of our knowledge, this is the first report of a case of de novo CD5+ DLBCL showing marked elevation of the PB basophil count. © 2006 Wiley-Liss, Inc.

The parameters involved in the Disease Activity Score of 28 joints (DAS28) are not mutually independent, and the evaluation excludes ankle and foot joints. We developed a new quantitative and comprehensive assessment of the activity of rheumatoid arthritis (RA), called the handy rheumatoid activity score, with 38 joints (HRAS38), to overcome these disadvantages of DAS28. Forty-six RA patients who recently completed a 1-year infliximab therapy were evaluated for DAS28 (C-reactive protein; CRP) and HRAS38 at 0, 2, 6, 14, 22, 30, 38, 46, and 54 weeks. The 38-joint evaluation in HRAS38 includes 28 joints of DAS28 except for the shoulder joints, with the addition of ankle and metatarsophalangeal joints. The extent of joint swelling was rated on a scale of 0-3. The HRAS38 score is the cumulative sum of three parameters including: (1) a global assessment of disease activity [visual analog scale (VAS) 0-100-mm] by the patient, (2) swollen joint score based on a 38-joint assessment by a physician (0-114), and (3) serum concentration of CRP (mg/l). Scatter plots of HRAS38 and DAS28(CRP), and subsequent linear regression analysis demonstrated a statistically significant correlation between methodologies (r = 0.846, P < 0.0001). Infliximab treatment resulted in a statistically significant (P < 0.001) decrease in the mean HRAS38 score from 130.5 to 56.5 within 2 weeks of treatment and at 52 weeks of therapy scores were still reduced at 52.5. The mean DAS28(CRP) was also significantly (P < 0.001) reduced from a baseline value of 5.8 to 3.7 after 2 weeks treatment with a final value of 3.2 after 52 weeks of therapy. Infliximab reduced the progression of joint destruction by 85%, for terms before infliximab as determined by radiographic analyses. The degree of progression appeared to be associated with the mean HRAS38, although this observation was not shown to be statistically significant by regression analysis (r = 0.307). The HRAS38 score comprises minimal and independently acquired parameters and is an effective and comprehensive measure of disease activity in RA patients. © Japan College of Rheumatology 2006.

Abstract: Substantial evidence supports that T-cells play a central role in the pathogenesis of systemic lupus erythematosus (SLE). To explore the molecular basis of the defective function of SLE T-cells, we focused on the signal transduction system via T-cell antigen receptor (TCR) in peripheral blood T-cells from SLE patients. Comprehensive analysis to identify the molecules responsible for the defects showed the expression of the TCR ζ chain was attenuated, or absent in more than half of SLE patients. Moreover, the aberrant transcripts of the TCR ζ chain, including spliced variants lacking exon 7 and with a short 3′-UTR, were detected in SLE T-cells. Although attenuated expression of the TCR ζ chain is also observed in patients with cancers, infections, and other autoimmune diseases, sustained attenuation of TCR ζ expression and aberrant transcripts are only observed in SLE. In this review we discuss the unique features of the TCR ζ defects in SLE. © 2006 Asia Pacific League of Associations for Rheumatology.