Efficacy and safety of sodium RISedronate for glucocorticoid-induced OsTeoporosis with rheumaTOid arthritis (RISOTTO study): A multicentre, double-blind, randomized, placebo-controlled trial.

OBJECTIVE: No evidence has shown the efficacy of Sodium Risedronate (Risedronate) for glucocorticoid-induced osteoporosis (GIO) in patients with Rheumatoid arthritis (RA). The aim of this study was to explore the effectiveness and safety of Risedronate for GIO complicated with RA. METHODS: This was a six-month randomized, double-blind, placebo-controlled trial of 95 patients with GIO complicated with RA from 19 centers. The primary endpoint was the change from baseline in lumbar spine bone mineral density (L-BMD). Secondary endpoints included changes in femoral neck and total hip BMD and bone turnover markers, as well as rheumatoid arthritis Disease Activity Score with 28-joint counts. Incident of non-traumatic spine fractures and adverse events were tracked as safety endpoints. RESULTS: Increase in L-BMD was significantly greater in the Risedronate group compared to the Placebo group (Risedronate: 3.49% [95% CI: 1.92-5.05] vs Placebo: 0.12% [95% CI: -2.07 to 2.30], p < .0001). No significant difference was found in the femoral neck and total hip BMD. Although adverse events were observed in 28 patients, none were considered serious. Non-traumatic vertebral fractures were identified in 10 patients. CONCLUSION: Risedronate was effective in increasing L-BMD and was well tolerated in patients with GIO complicated with RA.

Maintenance treatment using abatacept with dose reduction after achievement of low disease activity in patients with rheumatoid arthritis (MATADOR) - A prospective, multicenter, single arm pilot clinical trial.

OBJECTIVES: To preliminarily evaluate the feasibility of maintenance therapy with reduced dose of intravenous abatacept (ABT) to 250 mg/body/month after achieving remission or low disease activity (LDA). PATIENTS AND METHODS: RA patients treated with ABT at 13 sites were enrolled in this prospective interventional pilot study during the period between March 2013 and March 2015. Inclusion criteria were (1) age at 20 years or older, (2) under treatment with monthly intravenous ABT at approved doses, (3) DAS28-CRP lower than 2.7 at least for 6 months, (4) agreed to join this trial with written informed consent and (5) body weight under 125 kg. Enrolled patients were maintained with intravenous monthly ABT at a reduced dose of 250 mg/body (MATADOR protocol). The primary end point was the proportion of the patients continued with MATADOR protocol at week 48. MATADOR protocol was discontinued upon disease flare or other reasons such as patients' request or severe adverse event (AE). Disease activities and structural changes were also evaluated. RESULTS: Fifty-three patients fulfilled the entry criteria and were followed for 1-year. MATADOR protocol was continued for 1-year in 43 (81%) of the evaluated patients. Three patients experienced severe AEs. Mean DAS28-CRP and remission rate were 1.56 and 88% when ABT reduced and 1.80 and 81% at 1-year, respectively. Structural remission was achieved in 34 out of 42 evaluated patients. CONCLUSIONS: Reduced dose of intravenous ABT was proposed as a feasible choice for maintenance therapy for RA after achievement of remission/LDA, although further randomized trials would be awaited.

Low coseismic shear stress on the Tohoku-Oki megathrust determined from laboratory experiments.

Large coseismic slip was thought to be unlikely to occur on the shallow portions of plate-boundary thrusts, but the 11 March 2011 Tohoku-Oki earthquake [moment magnitude (Mw) = 9.0] produced huge displacements of ~50 meters near the Japan Trench with a resultant devastating tsunami. To investigate the mechanisms of the very large fault movements, we conducted high-velocity (1.3 meters per second) friction experiments on samples retrieved from the plate-boundary thrust associated with the earthquake. The results show a small stress drop with very low peak and steady-state shear stress. The very low shear stress can be attributed to the abundance of weak clay (smectite) and thermal pressurization effects, which can facilitate fault slip. This behavior provides an explanation for the huge shallow slip that occurred during the earthquake.

Two cases of mixed connective tissue disease complicated with thrombotic thrombocytopenic purpura.

Thrombotic thrombocytopenic purpura (TTP) is a rare complication of connective tissue diseases. Here, we describe 2 patients with mixed connective tissue disease (MCTD) who had pericardial effusion and TTP. They had moderately low to normal ADAMTS13 activity and no ADAMTS13 neutralizing antibodies. Both patients responded poorly to plasma exchange. One patient died due to multiple organ failure and the other due to infection. Although rare, TTP is an important complication that leads to a poor prognosis in MCTD patients.

Association of a functional polymorphism in the 3'-untranslated region of SPI1 with systemic lupus erythematosus.

OBJECTIVE: SPI1, also referred to as PU.1, is an Ets family transcription factor that interacts with IRF2, IRF4, and IRF8. In view of the significance of the type I interferon pathway in systemic lupus erythematosus (SLE), this study was undertaken to investigate a possible association between SPI1 polymorphisms and SLE. METHODS: A case-control association study was performed using 6 tag single-nucleotide polymorphisms (SNPs), as well as a SNP located upstream of SPI1 previously found to be associated with acute myelogenous leukemia, in 400 Japanese patients with SLE and 450 healthy controls. Resequencing of all exons and known regulatory regions was performed to identify functional polymorphisms. Association of genotype and SPI1 expression was examined using the GENEVAR database and reporter assays. RESULTS: A significant association was detected in 2 SNPs in intron 2 (rs10769258 and rs4752829) (P = 0.005 and P = 0.008, respectively, under the dominant model). The association was stronger in patients with nephropathy. Resequencing identified a potentially functional polymorphism in the 3'-untranslated region (3'-UTR), rs1057233, which was in strong linkage disequilibrium with the SNPs in intron 2. The number of risk alleles at rs1057233 was strongly correlated with SPI1 messenger RNA (mRNA) level in the database analysis (P = 0.0002), and was confirmed by a reporter assay. Interestingly, rs1057233 alters a target sequence for microRNA hsa-miR-569 (miR-569). Transfection experiments demonstrated that miR-569 inhibits expression of a reporter construct with the 3'-UTR sequence containing the nonrisk allele but not the risk allele. CONCLUSION: Our findings indicate that a SNP in the 3'-UTR of SPI1 is associated with elevated SPI1 mRNA level and with susceptibility to SLE.

High-dose unfractionated heparin therapy in a pregnant patient with antiphospolipid syndrome: a case report.

A case of a 37-year-old pregnant patient with antiphospholipid syndrome (APS), who has a medical history of both thrombosis and recurrent fetal loss, is presented. She was treated with predonisolone and fixed-dose unfractionated heparin (UFH) infusion, followed by plasmaphereses and fixed-dose low-molecular-weight heparin infusion during her fourth pregnancy. Unfortunately, this treatment did not have beneficial effects, resulting in intrauterine growth restriction and finally neonatal death. Continuous intravenous UFH infusion and low-dose aspirin were administrated under the monitoring of the activated partial thromboplastin time to achieve a target level of 120 s during her fifth pregnancy. A healthy baby weighing 1818 g at birth was delivered by Cesarean section at the 34th week of pregnancy. High-dose UFH infusion may be considered to be one of the preferable options to manage pregnant patients with refractory APS.

Mannose binding lectin gene polymorphism and the severity of chronic periodontitis.

OBJECTIVE: Mannose binding lectin (MBL) is a key molecule in first line defense against various microorganisms. Polymorphism of the MBL gene greatly affects serum MBL concentration, and is known to be associated with occurrence of infectious diseases. We aimed to determine whether there is a relationship between occurrence or severity of chronic periodontitis (CP) and polymorphism of the MBL gene. PATIENTS AND METHODS: Ninety-eight CP patients and 63 healthy subjects with no periodontitis were typed for the codon 54 polymorphism of the MBL gene by PCR-restriction fragment length polymorphism method. RESULTS: Genotype frequencies of the codon 54 polymorphism were similar between patients and control subjects. When patients were categorized to mild, moderate and severe periodontitis groups, possession of the low serum MBL concentration allele was a risk factor for having severe CP, as assessed by logistic regression analysis. CONCLUSION: Patients with MBL genotypes that cause lower serum MBL concentration may be at risk of having severe periodontitis. MBL gene typing may become useful to predict the prognosis of CP.

Replication of the association between the C8orf13-BLK region and systemic lupus erythematosus in a Japanese population.

OBJECTIVE: Recent genome-wide association studies identified an association between single-nucleotide polymorphisms (SNPs) in the C8orf13 region of BLK, the B lymphoid tyrosine kinase gene, with systemic lupus erythematosus (SLE) in Caucasians. The purpose of this study was to evaluate the significance of this region in the genetic background of Japanese patients with SLE. METHODS: Fourteen tag SNPs in the C8orf13-BLK region were genotyped in 327 Japanese patients with SLE and 322 healthy Japanese controls. The population-attributable risk percentage (PAR%) of rs13277113 in Japanese was compared with that in Caucasians as well as with that of other SLE susceptibility genes in Japanese. RESULTS: As in Caucasians, rs13277113A demonstrated the strongest association in Japanese (P = 1.73 x 10(-6) for the genotype frequency, P = 4.75 x 10(-7) for the allele frequency, odds ratio [OR] 2.44 [95% confidence interval (95% CI) 1.43-4.16]). The association in Japanese was consistent with a recessive model (P = 2.74 x 10(-7), OR 2.27 [95% CI 1.66-3.11]). In contrast to the Caucasian population, this risk allele was the major allele in the Japanese population. Because both the risk allele frequency and the OR were higher in Japanese than in Caucasians, the PAR% of rs13277113 was estimated to be much higher in Japanese (35.4%) than in Caucasians (16.2%), and the second highest among the 6 confirmed SLE susceptibility genes in Japanese. CONCLUSION: The association of the C8orf13-BLK region with SLE was replicated in a Japanese population. Contribution of this region to the genetic predisposition to SLE appeared to be greater in Japanese than in Caucasians.

Arthritogenic T cell epitope in glucose-6-phosphate isomerase-induced arthritis.

INTRODUCTION: Arthritis induced by immunisation with glucose-6-phosphate isomerase (GPI) in DBA/1 mice was proven to be T helper (Th) 17 dependent. We undertook this study to identify GPI-specific T cell epitopes in DBA/1 mice (H-2q) and investigate the mechanisms of arthritis generation. METHODS: For epitope mapping, the binding motif of the major histocompatibility complex (MHC) class II (I-Aq) from DBA/1 mice was identified from the amino acid sequence of T cell epitopes and candidate peptides of T cell epitopes in GPI-induced arthritis were synthesised. Human GPI-primed CD4+ T cells and antigen-presenting cells (APCs) were co-cultured with each synthetic peptide and the cytokine production was measured by ELISA to identify the major epitopes. Synthetic peptides were immunised in DBA/1 mice to investigate whether arthritis could be induced by peptides. After immunisation with the major epitope, anti-interleukin (IL) 17 monoclonal antibody (mAb) was injected to monitor arthritis score. To investigate the mechanisms of arthritis induced by a major epitope, cross-reactivity to mouse GPI peptide was analysed by flow cytometry and anti-GPI antibodies were measured by ELISA. Deposition of anti-GPI antibodies on the cartilage surface was detected by immunohistology. RESULTS: We selected 32 types of peptides as core sequences from the human GPI 558 amino acid sequence, which binds the binding motif, and synthesised 25 kinds of 20-mer peptides for screening, each containing the core sequence at its centre. By epitope mapping, human GPI325-339 was found to induce interferon (IFN) gamma and IL-17 production most prominently. Immunisation with human GPI325-339 could induce polyarthritis similar to arthritis induced by human GPI protein, and administration of anti-IL-17 mAb significantly ameliorated arthritis (p < 0.01). Th17 cells primed with human GPI325-339 cross-reacted with mouse GPI325-339, and led B cells to produce anti-mouse GPI antibodies, which were deposited on cartilage surface. CONCLUSIONS: Human GPI325-339 was identified as a major epitope in GPI-induced arthritis, and proved to have the potential to induce polyarthritis. Understanding the pathological mechanism of arthritis induced by an immune reaction to a single short peptide could help elucidate the pathogenic mechanisms of autoimmune arthritis.

Role of STAT4 polymorphisms in systemic lupus erythematosus in a Japanese population: a case-control association study of the STAT1-STAT4 region.

INTRODUCTION: Recent studies identified STAT4 (signal transducers and activators of transcription-4) as a susceptibility gene for systemic lupus erythematosus (SLE). STAT1 is encoded adjacently to STAT4 on 2q32.2-q32.3, upregulated in peripheral blood mononuclear cells from SLE patients, and functionally relevant to SLE. This study was conducted to test whether STAT4 is associated with SLE in a Japanese population also, to identify the risk haplotype, and to examine the potential genetic contribution of STAT1. To accomplish these aims, we carried out a comprehensive association analysis of 52 tag single nucleotide polymorphisms (SNPs) encompassing the STAT1-STAT4 region. METHODS: In the first screening, 52 tag SNPs were selected based on HapMap Phase II JPT (Japanese in Tokyo, Japan) data, and case-control association analysis was carried out on 105 Japanese female patients with SLE and 102 female controls. For associated SNPs, additional cases and controls were genotyped and association was analyzed using 308 SLE patients and 306 controls. Estimation of haplotype frequencies and an association study using the permutation test were performed with Haploview version 4.0 software. Population attributable risk percentage was estimated to compare the epidemiological significance of the risk genotype among populations. RESULTS: In the first screening, rs7574865, rs11889341, and rs10168266 in STAT4 were most significantly associated (P < 0.01). Significant association was not observed for STAT1. Subsequent association studies of the three SNPs using 308 SLE patients and 306 controls confirmed a strong association of the rs7574865T allele (SLE patients: 46.3%, controls: 33.5%, P = 4.9 x 10(-6), odds ratio 1.71) as well as TTT haplotype (rs10168266/rs11889341/rs7574865) (P = 1.5 x 10(-6)). The association was stronger in subgroups of SLE with nephritis and anti-double-stranded DNA antibodies. Population attributable risk percentage was estimated to be higher in the Japanese population (40.2%) than in Americans of European descent (19.5%). CONCLUSIONS: The same STAT4 risk allele is associated with SLE in Caucasian and Japanese populations. Evidence for a role of STAT1 in genetic susceptibility to SLE was not detected. The contribution of STAT4 for the genetic background of SLE may be greater in the Japanese population than in Americans of European descent.

Therapeutic effects of antibodies to tumor necrosis factor-alpha, interleukin-6 and cytotoxic T-lymphocyte antigen 4 immunoglobulin in mice with glucose-6-phosphate isomerase induced arthritis.

INTRODUCTION: Immunization with glucose-6-phosphate isomerase (GPI) induces severe arthritis in DBA/1 mice. The present study was designed to identify the cytokines and co-stimulatory molecules involved in the development of GPI-induced arthritis. METHODS: Arthritis was induced in DBA/1 mice with 300 microg human recombinant GPI. CD4+ T cells and antigen-presenting cells from splenocytes of arthritic mice were cultured in the presence of GPI. Tumor necrosis factor (TNF)-alpha, IFN-gamma, IL-2, IL-4, IL-5, IL-6, IL-10, and IL-12 levels were assessed using cytometric bead array. Monoclonal antibodies to TNF-alpha, IFN-gamma, IL-12, CD40L, inducible co-stimulator (ICOS), and cytotoxic T-lymphocyte antigen 4 immunoglobulin (CTLA-4Ig) were used to block TNF-alpha and IFN-gamma production, examine clinical index in mice with GPI-induced arthritis, and determine anti-GPI antibody production. RESULTS: Large amounts of TNF-alpha and IFN-gamma and small amounts of IL-2 and IL-6 were produced by splenocytes from mice with GPI-induced arthritis. Anti-TNF-alpha mAbs and CTLA-4Ig suppressed TNF-alpha production, whereas anti-IFN-gamma mAbs, anti-IL-12 mAbs, and CTLA-4 Ig inhibited IFN-gamma production. A single injection of anti-TNF-alpha and anti-IL-6 mAbs and two injections of CTLA-4Ig reduced the severity of arthritis in mice, whereas injections of anti-IFN-gamma and anti-IL-12 mAbs tended to exacerbate arthritis. Therapeutic efficacy tended to correlate with reduction in anti-GPI antibodies. CONCLUSION: TNF-alpha and IL-6 play an important role in GPI-induced arthritis, whereas IFN-gamma appears to function as a regulator of arthritis. Because the therapeutic effects of the tested molecules used in this study are similar to those in patients with rheumatoid arthritis, GPI-induced arthritis appears to be a suitable tool with which to examine the effect of various therapies on rheumatoid arthritis.

Tristetraprolin (TTP) gene polymorphisms in patients with rheumatoid arthritis and healthy individuals.

Tristetraprolin (TTP) is an intracellular protein that modulates the production of cytokines, including TNFalpha, by binding to and destabilizing the mRNAs of these cytokines. Therefore, differences in TTP gene expression may affect the severity of inflammatory diseases, such as rheumatoid arthritis (RA). We searched for polymorphisms in the human TTP gene and for this purpose, we sequenced the entire TTP gene in 20 Japanese individuals (ten with RA and ten healthy volunteers) and found one single nucleotide polymorphism (SNP) in the promoter region. We analyzed this SNP (A/G) by restriction fragment length polymorphism method in 155 RA patients and 100 control subjects. While the frequency of A allele in this SNP was similar in RA patients (74.5%) and controls (76.0%), the disease duration in RA patients with genotype GG was shorter than that of patients with genotypes AA/AG and RA patients with genotype GG had a higher probability of being treated with infliximab. We studied the difference in promoter activity between the two alleles by luciferase assay and found that the promoter activity of TTP promoter region with allele A was around two-fold higher than that with allele G. We conclude that this SNP in the promoter region of the TTP gene mildly affects promoter activity, and thus, may influence the disease activity of inflammatory disorders including RA.

Crucial role of the interleukin-6/interleukin-17 cytokine axis in the induction of arthritis by glucose-6-phosphate isomerase.

OBJECTIVE: To clarify the glucose-6-phosphate isomerase (GPI)-specific CD4+ T cell lineage involved in GPI-induced arthritis and to investigate their pathologic and regulatory roles in the induction of the disease. METHODS: DBA/1 mice were immunized with GPI to induce arthritis. CD4+ T cells and antigen-presenting cells were cocultured with GPI, and cytokines in the supernatant were analyzed by enzyme-linked immunosorbent assay. Anti-interferon-gamma (anti-IFNgamma) monoclonal antibody (mAb), anti-interleukin-17 (anti-IL-17) mAb, or the murine IL-6 receptor (IL-6R) mAb MR16-1 was injected at different time points, and arthritis development was monitored visually. After MR16-1 was injected, percentages of Th1, Th2, Th17, and Treg cells were analyzed by flow cytometry, and CD4+ T cell proliferation was analyzed using carboxyfluorescein diacetate succinimidyl ester. RESULTS: GPI-specific CD4+ T cells were found to be differentiated to Th1 and Th17 cells, but not Th2 cells. Administration of anti-IL-17 mAb on day 7 significantly ameliorated arthritis (P < 0.01), whereas administration of anti-IFNgamma mAb exacerbated arthritis. Neither anti-IL-17 mAb nor anti-IFNgamma mAb administration on day 14 ameliorated arthritis. Administration of MR16-1 on day 0 or day 3 protected against arthritis induction, and MR16-1 administration on day 8 significantly ameliorated existing arthritis (P < 0.05). After administration of MR16-1, there was marked suppression of Th17 differentiation, without an increase in Th1, Th2, or Treg cells, and CD4+ T cell proliferation was also suppressed. CONCLUSION: IL-6 and Th17 play an essential role in GPI-induced arthritis. Since it has previously been shown that treatment with a humanized anti-IL-6R mAb has excellent effects in patients with rheumatoid arthritis (RA), we propose that the IL-6/IL-17 axis might also be involved in the generation of RA, especially in the early effector phase.

Interleukin-17 gene expression in patients with rheumatoid arthritis.

Interleukin-17 is a proinflammatory cytokine. Recent animal studies have shown that IL-17 plays a role in the initiation and progression of arthritis. However, whether IL-17 has a prominent role in human rheumatoid arthritis (RA) or not remains unclear. Here we investigated the role of IL-17 in patients with RA. cDNA was prepared from knee joint synovial tissues of RA (n = 11) and osteoarthritic (OA, n = 10) patients and PBMC of RA (n = 52) and healthy subjects (n = 34). IL-17 gene expression level was measured by real-time PCR, and was compared with various clinical parameters. IL-17 gene expression in synovial tissues of RA was similar to that in OA. IL-17 gene expression level in PBMC of RA patients was significantly higher than in the control. The response (changes in DAS) to two-week treatment with anti-TNF-alpha blockers (infliximab or etanercept) did not correlate with changes in IL-17 gene expression levels. The IL-17/TNF-alpha gene expression ratio at baseline (before treatment) tended to be lower in responders to the treatment. Expression of IL-17 gene in PBMC may be associated with the inflammatory process of RA. IL-17/TNF-alpha expression ratio is a potentially suitable marker of response to anti-TNF-alpha therapy.

Autoantibodies against protective molecules--C1q, C-reactive protein, serum amyloid P, mannose-binding lectin, and apolipoprotein A1: prevalence in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of several autoantibodies. Among the multiple factors involved in SLE development, apoptotic defects and impaired clearance of cellular debris have gained considerable interest, as they contribute to autoantigen overload. Several molecules of the innate immunity, also participate in the removal of damaged and apoptotic cells. Among them are C1q, C-reactive protein (CRP), serum amyloid P protein (SAP), mannose-binding lectin (MBL), and apolipoprotein A1 (APO A1). To evaluate the prevalence of autoantibodies against CRP, SAP, MBL, APO A1, and C1q among SLE patients, and their relationship with disease activity, a total of 150 SLE patients were screened for the presence of elevated antibody titers against C1q, CRP, SAP, MBL, and APO A1, utilizing the enzyme-linked immunosorbent assay (ELISA) method. Disease activity was assessed using the ECLAM or SLEDAI scores. The study population comprised two groups of patients: 100 patients with quiescent disease (median ECLAM score 2) comprised the first group, and 50 patients with active disease (median SLEDAI score 16) comprised group 2. Elevated titers of anti-CRP antibodies were significantly elevated only in group 1 (10% versus 4% of controls). Antibodies against SAP were evaluated only among patients in group 1, and were found at a significant high prevalence (20%). Elevated titers of anti-MBL antibodies were significantly elevated only in group 1 (15% versus 3.6%); and antibodies directed against APO A1 were significantly elevated in 21% of group 1, and 50% of group 2 patients. Elevated titers of anti-C1q were evaluated only in group 2, and were found at a significant prevalence of 66%. Significant correlation with disease activity was found only for anti-APO A1 antibodies, and only in group 1. Several patients harbored more than one of the autoantibodies tested. In patients with SLE, autoantibodies directed against protective molecules, that is, acute-phase proteins involved in the disposal of cellular and nuclear debris, can be detected. These autoantibodies may play a pathogenic role in the development or perpetuation of autoimmunity in SLE.

Successful treatment of refractory thrombotic thrombocytopenic purpura with cyclosporine and corticosteroids in a patient with systemic lupus erythematosus and antibodies to ADAMTS13.

A 46-year-old woman with systemic lupus erythematosus was hospitalized for purpura, hematochezia and hematuria. One week after admission, she developed grand mal seizures and coma and was diagnosed with thrombotic thrombocytopenic purpura (TTP) when fragmented red cells were found on the peripheral blood smear. Laboratory findings showed severe ADAMTS13 (a disintegrin-like and metalloprotease with thrombospondin type 1 repeats) deficiency and anti-ADAMTS13 antibodies, which in recent reports have indicated a poor prognosis. She was refractory to methylprednisolone pulse therapy and plasma exchange, but administration of cyclosporine induced remission without adverse effects. We propose that cyclosporine may be an effective treatment for cases of refractory TTP.

Biased usage of synovial immunoglobulin heavy chain variable region 4 by the anti-glucose-6-phosphate isomerase antibody in patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) is the most common inflammatory arthritis, characterized by marked infiltration of mononuclear cells including B cells into the inflamed synovium. Anti-glucose-6-phosphate isomerase (GPI) antibody (Ab) is an arthritogenic Ab in K/BxN T cell receptor transgenic mice, and is also present in some patients with RA. To characterize synovial B cells from anti-GPI Ab-positive RA, synovial immunoglobulin (Ig) heavy chain variable regions (VH) were compared with those of negative individuals. Synovial tissues were obtained from six RA patients (three anti-GPI Ab-positive and three anti-GPI Ab-negative). Ig-VH genes were amplified by PCR using family-specific primers and were subsequently sequenced. In synovial B cells from anti-GPI Ab-positive RA patients, VH4 and JH4 were predominantly expressed (p<0.0001). The immunoglobulin heavy chain complementarity-determining region 3 (IgH-CDR3) length in the synovium of anti-GPI Ab-positive individuals was shorter than that in anti-GPI Ab-negative individuals (p=0.0005). In addition, the IgH-CDR3 of anti-GPI Ab-positive patients was rich in basic-ionized amino acids (arginine, histidine, and lysine) near their central position, suggesting a high affinity. Our results support the notion that Ig-VH4 B cells in RA synovium with anti-GPI Ab are affinity-matured and that anti-GPI Ab might be associated with the skewed IgH-CDR3.

Effects of infliximab therapy on gene expression levels of tumor necrosis factor alpha, tristetraprolin, T cell intracellular antigen 1, and Hu antigen R in patients with rheumatoid arthritis.

OBJECTIVE: Tristetraprolin (TTP), T cell intracellular antigen 1 (TIA-1), and Hu antigen R (HuR) are adenine/uridine-rich element binding proteins (ABPs) that affect the production of tumor necrosis factor alpha (TNFalpha) by binding to TNF messenger RNA (mRNA). TTP promotes deadenylation, TIA-1 inhibits translation, and HuR stabilizes TNFalpha mRNA. The aims of this study were to understand the posttranscriptional control of TNFalpha production in patients with rheumatoid arthritis (RA), and to identify parameters that may predict the efficacy of anti-TNFalpha therapy. METHODS: Peripheral blood mononuclear cells from 38 patients with RA were obtained before therapy and 2 weeks and 54 weeks after administration of the first dose of infliximab, and from 20 healthy control subjects. TNFalpha, TTP, TIA-1, and HuR gene expression levels were analyzed by real-time polymerase chain reaction. RESULTS: At baseline, TTP and HuR gene expression levels, as well as the TTP:TNFalpha, TTP:HuR, and TIA-1:TNFalpha gene expression ratios were lower in patients with RA than in control subjects, while expression of TNFalpha, TIA-1, and TIA-1:HuR was higher in patients with RA. The TTP:HuR expression ratio decreased significantly after administration of infliximab. Positive correlations were observed between TNFalpha and TTP, TNFalpha and TIA-1, TIA-1 and HuR, and TNFalpha and HuR gene expression in both healthy control subjects and patients with RA. At baseline, the TIA-1:HuR ratio tended to be higher in patients who achieved 50% improvement according to the American College of Rheumatology criteria (ACR50) at week 54 than in those who did not achieve at least an ACR20 response. CONCLUSION: Differences in ABP gene expression may affect TNFalpha gene expression. A higher TIA-1:HuR expression ratio might correlate with the response to infliximab therapy.