A potential role of protein extractions from Metagonimus yokogawai in amelionating inflammation in patients with ankylosing spondylitis.

Helminth infections and their components has been recognized to have a positive impact on the immune system. This study aimed to investigate the potential of Metagonimus yokogawai-derived proteins (MYp) to provide protection against ankylosing spondylitis (AS) through modulation of immune responses. The cytotoxicity of MYp at various doses was first assessed using MTS and flow cytometry. Peripheral blood mononuclear cells (PBMCs) were collected from AS patients, and the production of inflammatory cytokines was analyzed through flow cytometry. In the experiments with SKG mice, MYp or vehicle was administered and inflammation was evaluated through immunohistochemistry and enzyme-linked immunosorbent assay. The results showed that MYp did not decrease cell viability of PBMCs even after 48 h. Additionally, the frequencies of IFN-γ and IL-17A producing cells were significantly reduced after MYp treatment in the PBMC cultures. Furthermore, MYp treatment significantly suppressed arthritis and enthesitis in the SKG mouse model. The results suggest the first evidence that MYp can effectively alleviate clinical symptoms and restore cytokine balance in patients with AS.

CCL20 inhibition for treating inflammation in ankylosing spondylitis.

OBJECTIVES: Th17 cells are known to play a significant role in AS. C-C motif chemokine ligand 20 (CCL20) binds to C-C chemokine receptor 6 (CCR6) on Th17 cells, promoting their migration to inflammation sites. The aim of this research is to examine the effectiveness of CCL20 inhibition in treating inflammation in AS. METHODS: Mononuclear cells from peripheral blood (PBMC) and SF (SFMC) were collected from healthy individuals and AS. Flow cytometry was used to analyse cells producing inflammatory cytokines. CCL20 levels were determined using ELISA. The impact of CCL20 on Th17 cell migration was verified using a Trans-well migration assay. The in vivo efficacy of CCL20 inhibition was evaluated using an SKG mouse model. RESULTS: The presence of Th17 cells and CCL20 expressing cells was higher in SFMCs from AS patients compared with their PBMCs. The CCL20 level in AS SF was significantly higher than in OA patients. The percentage of Th17 cells in PBMCs from AS patients increased when exposed to CCL20, whereas the percentage of Th17 cells in SFMCs from AS patients decreased when treated with CCL20 inhibitor. The migration of Th17 cells was found to be influenced by CCL20, and this effect was counteracted by the CCL20 inhibitor. In the SKG mouse model, the use of CCL20 inhibitor significantly reduced joint inflammation. CONCLUSION: This research validates the critical role of CCL20 in AS and suggests that targeting CCL20 inhibition could serve as a novel therapeutic approach for AS treatment.

IL-6 activates pathologic Th17 cell via STAT 3 phosphorylation in inflammatory joint of Ankylosing Spondylitis.

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease, which is characterized by inflammation of the axial skeleton and the peripheral arthritis. An increase in the number of Th17 cells in patients with AS has been reported. Although Th17 cells have been involved in the induction of inflammation, recent data suggest that not all Th17 cells are pathogenic, showing regulatory function of Th17 cell. Cells producing both interferon-gamma (IFN-γ) and interleukin (IL)-17 have been reported to be the main pathologic Th17 (pTh17) cells that induce inflammation at sites of joint. Emerging evidence demonstrated that IL-6 has a main role in regulating the balance between inflammatory and regulatory T cells. However, there is no direct study to assess pTh17 cell with IL-6 in AS. Therefore, we evaluated the effect of IL-6 on pTh17 cell activation, and it's mechanism, using ex vivo and mouse model of AS. As a result, we found that pTh17 cell is dependent on the cytokine milieu with IL-6. We confirmed pTh17 cells play a pathogenic role at sites of inflammation. As a mechanism, it was revealed that IL-6 induced STAT 3 phosphorylation contributes to the increased pTh17 responses in AS patients with peripheral arthritis. Though validation of our results is required, IL-6 inhibitor can be a promising treatment for inflammation in AS patients with peripheral arthritis.

Biological insights into systemic lupus erythematosus through an immune cell-specific transcriptome-wide association study.

OBJECTIVE: Genome-wide association studies (GWAS) have identified >100 risk loci for systemic lupus erythematosus (SLE), but the disease genes at most loci remain unclear, hampering translation of these genetic discoveries. We aimed to prioritise genes underlying the 110 SLE loci that were identified in the latest East Asian GWAS meta-analysis. METHODS: We built gene expression predictive models in blood B cells, CD4+ and CD8+ T cells, monocytes, natural killer cells and peripheral blood cells of 105 Japanese individuals. We performed a transcriptome-wide association study (TWAS) using data from the latest genome-wide association meta-analysis of 208 370 East Asians and searched for candidate genes using TWAS and three data-driven computational approaches. RESULTS: TWAS identified 171 genes for SLE (p<1.0×10-5); 114 (66.7%) showed significance only in a single cell type; 127 (74.3%) were in SLE GWAS loci. TWAS identified a strong association between CD83 and SLE (p<7.7×10-8). Meta-analysis of genetic associations in the existing 208 370 East Asian and additional 1498 cases and 3330 controls found a novel single-variant association at rs72836542 (OR=1.11, p=4.5×10-9) around CD83. For the 110 SLE loci, we identified 276 gene candidates, including 104 genes at recently-identified SLE novel loci. We demonstrated in vitro that putative causal variant rs61759532 exhibited an allele-specific regulatory effect on ACAP1, and that presence of the SLE risk allele decreased ACAP1 expression. CONCLUSIONS: Cell-level TWAS in six types of immune cells complemented SLE gene discovery and guided the identification of novel genetic associations. The gene findings shed biological insights into SLE genetic associations.

Amino acid signatures of HLA Class-I and II molecules are strongly associated with SLE susceptibility and autoantibody production in Eastern Asians.

Human leukocyte antigen (HLA) is a key genetic factor conferring risk of systemic lupus erythematosus (SLE), but precise independent localization of HLA effects is extremely challenging. As a result, the contribution of specific HLA alleles and amino-acid residues to the overall risk of SLE and to risk of specific autoantibodies are far from completely understood. Here, we dissected (a) overall SLE association signals across HLA, (b) HLA-peptide interaction, and (c) residue-autoantibody association. Classical alleles, SNPs, and amino-acid residues of eight HLA genes were imputed across 4,915 SLE cases and 13,513 controls from Eastern Asia. We performed association followed by conditional analysis across HLA, assessing both overall SLE risk and risk of autoantibody production. DR15 alleles HLA-DRB1*15:01 (P = 1.4x10-27, odds ratio (OR) = 1.57) and HLA-DQB1*06:02 (P = 7.4x10-23, OR = 1.55) formed the most significant haplotype (OR = 2.33). Conditioned protein-residue signals were stronger than allele signals and mapped predominantly to HLA-DRB1 residue 13 (P = 2.2x10-75) and its proxy position 11 (P = 1.1x10-67), followed by HLA-DRB1-37 (P = 4.5x10-24). After conditioning on HLA-DRB1, novel associations at HLA-A-70 (P = 1.4x10-8), HLA-DPB1-35 (P = 9.0x10-16), HLA-DQB1-37 (P = 2.7x10-14), and HLA-B-9 (P = 6.5x10-15) emerged. Together, these seven residues increased the proportion of explained heritability due to HLA to 2.6%. Risk residues for both overall disease and hallmark autoantibodies (i.e., nRNP: DRB1-11, P = 2.0x10-14; DRB1-13, P = 2.9x10-13; DRB1-30, P = 3.9x10-14) localized to the peptide-binding groove of HLA-DRB1. Enrichment for specific amino-acid characteristics in the peptide-binding groove correlated with overall SLE risk and with autoantibody presence. Risk residues were in primarily negatively charged side-chains, in contrast with rheumatoid arthritis. We identified novel SLE signals in HLA Class I loci (HLA-A, HLA-B), and localized primary Class II signals to five residues in HLA-DRB1, HLA-DPB1, and HLA-DQB1. These findings provide insights about the mechanisms by which the risk residues interact with each other to produce autoantibodies and are involved in SLE pathophysiology.

Meta-analysis of 208370 East Asians identifies 113 susceptibility loci for systemic lupus erythematosus.

OBJECTIVE: Systemic lupus erythematosus (SLE), an autoimmune disorder, has been associated with nearly 100 susceptibility loci. Nevertheless, these loci only partially explain SLE heritability and their putative causal variants are rarely prioritised, which make challenging to elucidate disease biology. To detect new SLE loci and causal variants, we performed the largest genome-wide meta-analysis for SLE in East Asian populations. METHODS: We newly genotyped 10 029 SLE cases and 180 167 controls and subsequently meta-analysed them jointly with 3348 SLE cases and 14 826 controls from published studies in East Asians. We further applied a Bayesian statistical approach to localise the putative causal variants for SLE associations. RESULTS: We identified 113 genetic regions including 46 novel loci at genome-wide significance (p<5×10-8). Conditional analysis detected 233 association signals within these loci, which suggest widespread allelic heterogeneity. We detected genome-wide associations at six new missense variants. Bayesian statistical fine-mapping analysis prioritised the putative causal variants to a small set of variants (95% credible set size ≤10) for 28 association signals. We identified 110 putative causal variants with posterior probabilities ≥0.1 for 57 SLE loci, among which we prioritised 10 most likely putative causal variants (posterior probability ≥0.8). Linkage disequilibrium score regression detected genetic correlations for SLE with albumin/globulin ratio (rg=-0.242) and non-albumin protein (rg=0.238). CONCLUSION: This study reiterates the power of large-scale genome-wide meta-analysis for novel genetic discovery. These findings shed light on genetic and biological understandings of SLE.

STAT3 phosphorylation inhibition for treating inflammation and new bone formation in ankylosing spondylitis.

OBJECTIVE: AS is a rheumatic disease characterized by chronic inflammation and bony ankylosis. This study was to evaluate whether a signal transducer and activator of transcription 3 phosphorylation inhibitor (stat3-p Inh) could treat both chronic inflammation and bone formation in AS. METHODS: Primary AS osteoprogenitor cells and spinal entheseal cells were examined for osteogenic differentiation. SF mononuclear cells (SFMCs) and lamina propria mononuclear cells (LPMCs) were obtained from AS patients. Inflammatory cytokine-producing cells were analysed using flow cytometry and ELISA. Female SKG mice were treated with stat3-p Inh, IL-17A blocker or vehicle. Inflammation and new bone formation were evaluated using immunohistochemistry, PET and micro-CT. RESULTS: In the SKG mouse model, stat3-p Inh significantly suppressed arthritis, enthesitis, spondylitis and ileitis. In experiments culturing SFMCs and LPMCs, the frequencies of IFN-γ-, IL-17A- and TNF-α-producing cells were significantly decreased after stat3-p Inh treatment. When comparing current treatments for AS, stat3-p Inh showed a comparable suppression effect on osteogenesis to Janus kinase inhibitor or IL-17A blocker in AS-osteoprogenitor cells. Stat3-p Inh suppressed differentiation and mineralization of AS-osteoprogenitor cells and entheseal cells toward osteoblasts. Micro-CT analysis of hind paws revealed less new bone formation in stat3-p Inh-treated mice than vehicle-treated mice (P = 0.005). Hind paw and spinal new bone formation were similar between stat3-p Inh- and anti-IL-17A-treated SKG mice (P = 0.874 and P = 0.117, respectively). CONCLUSION: Stat-3p inhibition is a promising treatment for both inflammation and new bone formation in AS.

Patient Perspectives and Preferences Regarding Gout and Gout Management: Impact on Adherence.

BACKGROUND: Patient-centered management is becoming increasingly important in gout, but there are limited studies exploring patients' perspectives and preferences. We aimed to investigate patients' perspectives and preferences regarding gout and gout management, and their impacts on adherence to urate lowering therapy (ULT). METHODS: A paper-based survey was performed in patients with gout seen at the rheumatology outpatient clinics of 16 tertiary hospitals. The survey included questions regarding demographics, comorbidities, gout attacks, current treatment and adherence, and patients' perspectives and preferences regarding gout and gout management. Multivariate regression analysis was performed to determine the factors associated with ULT adherence. RESULTS: Of 809 surveyed patients with gout, 755 (94.5%) were using ULT. Among those using ULT, 89.1% had ≥ 80% adherence to ULT. Majority of the patients knew management strategies to some extent (94.8%), perceived gout as a life-long disease (91.2%), and were making efforts toward practicing at least one lifestyle modification (89.2%). Most patients (71.9%) obtained information about gout management during their clinic visits. Approximately half of the patients (53.6%) preferred managing their disease with both ULT and lifestyle modification, 28.4% preferred ULT only, and 17.4% preferred lifestyle modification only. Adherence was better in patients with older age (odds ratio [OR], 1.03), those with better knowledge of gout management strategies (OR, 3.56), and those who had preference for ULT (OR, 2.07). CONCLUSION: Patients' perspectives and management preferences had high impacts on adherence to ULT in gout. Consideration of patients' perspectives and preferences is important for achieving the desired clinical outcome in gout.

Genome-wide association study in a Korean population identifies six novel susceptibility loci for rheumatoid arthritis.

OBJECTIVE: Genome-wide association studies (GWAS) in rheumatoid arthritis (RA) have discovered over 100 RA loci, explaining patient-relevant RA pathogenesis but showing a large fraction of missing heritability. As a continuous effort, we conducted GWAS in a large Korean RA case-control population. METHODS: We newly generated genome-wide variant data in two independent Korean cohorts comprising 4068 RA cases and 36 487 controls, followed by a whole-genome imputation and a meta-analysis of the disease association results in the two cohorts. By integrating publicly available omics data with the GWAS results, a series of bioinformatic analyses were conducted to prioritise the RA-risk genes in RA loci and to dissect biological mechanisms underlying disease associations. RESULTS: We identified six new RA-risk loci (SLAMF6, CXCL13, SWAP70, NFKBIA, ZFP36L1 and LINC00158) with pmeta<5×10-8 and consistent disease effect sizes in the two cohorts. A total of 122 genes were prioritised from the 6 novel and 13 replicated RA loci based on physical distance, regulatory variants and chromatin interaction. Bioinformatics analyses highlighted potentially RA-relevant tissues (including immune tissues, lung and small intestine) with tissue-specific expression of RA-associated genes and suggested the immune-related gene sets (such as CD40 pathway, IL-21-mediated pathway and citrullination) and the risk-allele sharing with other diseases. CONCLUSION: This study identified six new RA-associated loci that contributed to better understanding of the genetic aetiology and biology in RA.

Positive histopathologic assessment in salivary glands shows little impact on clinical features of established primary Sjögren's syndrome in a Korean population.

OBJECTIVES: The presence and severity of focal lymphocytic sialadenitis in minor salivary glands is a pathognomonic feature in primary Sjögren's syndrome (pSS). However, it has not been determined whether performing minor salivary gland biopsy (MSGB) in a setting of serologically and clinically established pSS provides additional clinical value. Therefore, we aimed to investigate the necessity of MSGB in established pSS patients with anti-Ro/SSA antibodies. METHODS: We extracted 185 patients with anti-Ro/SSA antibody-positive pSS from the Korean Initiative of pSS study, a prospective cohort study. We assigned them into two groups, 161 patients with focus scores ≥1 and another 24 with focus scores <1. The two groups were compared in various clinical aspects, including the severity of glandular dysfunction, systemic disease activity, extra- glandular manifestations, and other clinical indices and laboratory values. We also evaluated the relationship between focus scores and clinically important variables in pSS. RESULTS: Between the two groups, there were no significant differences in the severity of secretory dysfunction, the frequency of extra-glandular manifestations, systemic disease activity represented by various clinical indices, and laboratory findings possibly predicting the risk for lymphoma. Rather, theSjögren's syndrome disease damage index was higher in the group with focusscores <1. Among all variables, only serum immunoglobulin G levels were correlated with focus scores. CONCLUSIONS: Given the little influence on clinical phenotypes, routine MSGB could be omitted for serologically and clinically established pSS patients, especially in low-risk areas for lymphoproliferative diseases.

Efficacy and Safety of Rituximab in Korean Patients with Refractory Inflammatory Myopathies.

BACKGROUND: Rituximab (RTX), a monoclonal antibody that selectively binds to CD20+ B cells, showed favorable outcomes in patients with idiopathic inflammatory myopathies (IIM) in small case series, but the evidence is still not enough. Our goal was to determine the efficacy and safety of RTX for Korean patients with refractory IIM. METHODS: We retrospectively analyzed the medical records of 16 patients with refractory IIM treated with RTX in seven tertiary rheumatology clinics in the Korea. The efficacy of RTX was evaluated with the improvement of serum creatine phosphokinase (CPK) level and physician's global assessment (PGA), and daily corticosteroid dose reduction. A > 25% decrease in CPK level, corticosteroid dose, or PGA was considered significant. A complete response (CR) was designated by meeting three efficacy criteria and a partial response (PR) by only two criteria. RESULTS: Sixteen patients with IIM were evaluated (13 female; median age, 51.8 years). All patients had received at least one conventional immunosuppressive agent (median, 3.6 [2.0-5.0]) and concomitant corticosteroids. The median CPK level and median dose of prednisolone was 421.0 units/L and 20.0 mg/day respectively. Eleven patients were treated with intravenous immunoglobulin. Seven patients received 2,000 mg of RTX and the others received lower dose. Twenty-four weeks after RTX treatment, 11 patients achieved a > 25% reduction in corticosteroid dose and CPK levels, and nine showed improved PGA. The overall response rate was 68.8% (11 patients). At the end of follow-up (median 24 weeks), 12 (75.0%) patients responded overall: four (25.0%) and eight (50.0%) patients achieved CR and PR, respectively. Baseline muscle enzyme levels were higher in responders than non-responders, but disease duration, RTX dose, ESR and serum CRP were not significantly different between the two groups. The rate of adverse event was 25.4/1,000 person-years. CONCLUSION: RTX could be an effective and relatively safe therapeutic option in patients with refractory IIM.

Efficacy and safety of switching from rituximab to biosimilar CT-P10 in rheumatoid arthritis: 72-week data from a randomized Phase 3 trial.

OBJECTIVE: To evaluate the efficacy and safety of CT-P10, a rituximab biosimilar after a single switch, during a multinational, randomized, double-blind Phase 3 trial involving patients with RA. METHODS: Patients received 48 weeks' treatment with CT-P10 or United States- or European Union-sourced reference rituximab (US-RTX and EU-RTX, respectively). Patients entering the extension period (weeks 48-72) remained on CT-P10 (CT-P10/CT-P10; n = 122) or US-RTX (US-RTX/US-RTX; n = 64), or switched to CT-P10 from US-RTX (US-RTX/CT-P10; n = 62) or EU-RTX (EU-RTX/CT-P10; n = 47) for an additional course. Efficacy endpoints included Disease Activity Score using 28 joints (DAS28), American College of Rheumatology (ACR) response rates, and quality of life-related parameters. Pharmacodynamics, immunogenicity and safety were also assessed. RESULTS: At week 72, similar improvements were observed by disease activity parameters including DAS28 and ACR response rate in the four extension period treatment groups. Quality of life improvements at week 72 vs baseline were similarly shown during the extension period in all groups. Newly developed anti-drug antibodies were detected in two patients following study drug infusion in the extension period. Similar pharmacodynamic and safety profiles were observed across groups. CONCLUSION: Long-term use of CT-P10 up to 72 weeks was effective and well tolerated. Furthermore, switching from reference rituximab to CT-P10 in RA was well tolerated and did not result in any clinically meaningful differences in terms of efficacy, pharmacodynamics, immunogenicity and safety. TRAIL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov, NCT02149121.

Distinct clinical characteristics of anti-Ro/SSA-negative primary Sjögren's syndrome: data from a nationwide cohort for Sjögren's syndrome in Korea.

OBJECTIVES: To investigate clinical characteristics of patients with primary Sjögren's syndrome (SS) who were negative for anti-Ro/SSA antibody but positive for minor salivary gland biopsy (MSGB) compared to patients who presented positivity for anti-Ro/SSA antibody. METHODS: The data of 355 patients from the Korean Initiative of primary Sjögren's Syndrome (KISS), a nationwide prospective cohort for primary SS in Korea, were analysed. All patients fulfilled the 2016 American College of Rheumatology/European League Against Rheumatism (EULAR) classification criteria. Of these patients, 326 were positive for anti-Ro/SSA antibody and 29 were antibody-negative, although they had positive findings in MSGB. Various clinical features including all kinds of tests for evaluating secretory function, disease-related clinical indices and serological values available in the cohort were compared between the two groups. RESULTS: The anti-Ro/SSA-negative group showed less rheumatoid factor positivity (p<0.001), leucopenia (p=0.003), hyper-gammaglobulinaemia (p<0.001), lower serum ß2-microglobulin level (p=0.034), more anti-centromere antibody positivity (p<0.001), higher score in dryness domain of EULAR SS patient-reported index (p=0.048) and more positivity for peripheral nervous system domain in EULAR SS disease activity index and loss of teeth in SS disease damage index (p=0.021 and 0.041, respectively) than patients who were positive for anti-Ro/ SSA antibody. CONCLUSIONS: Primary SS patients who are negative for anti-Ro/SSA antibody have different clinical characteristics compared to patients who are positive for such antibody in Korea. Therefore, clinicians should consider MSGB in patients with suspicious symptoms who are anti-Ro/SSA-negative.

Performance of the 2016 ACR-EULAR classification criteria for primary Sjogren's syndrome in a Korean cohort.

This study compared the performance of the newly proposed 2016 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) criteria to the 2002 American-European Consensus Group (AECG) and 2012 ACR classification criteria for primary Sjogren's syndrome (pSS) in well-characterized Korean patients. Patients with pSS from 12 university-affiliated hospitals in Korea were enrolled from October 2013 to January 2017. Clinical and laboratory data were reviewed. For the validation set, patients who underwent evaluation tests to rule out pSS at Seoul St. Mary's hospital from November 2016 to December 2017 were analyzed. Baseline registry data were available in 458 patients, and 328 patients had sufficient data to determine the fulfillment of each criteria set. All three sets of criteria were met by 307 patients (93.6%). The newly proposed 2016 ACR/EULAR criteria were met by 325 patients (99.1%). The 2002 AECG and 2012 ACR criteria were met by 325 (99.1%) and 310 patients (94.5%), respectively. In a validation cohort consisting of 161 patients with pSS-related symptoms/signs, the sensitivity and specificity of the 2016 ACR/EULAR criteria were 100% [95% confidence interval (CI), 96.11-100.00] and 81.8% [95% CI, 76.15-94.26], respectively. Agreement between the 2016 criteria and 2012 or 2002 criteria was high (Cohen's kappa 0.736 and 0.769, respectively). The newly proposed 2016 ACR/EULAR criteria were met by most patients diagnosed with pSS according to previous criteria and showed higher sensitivity and lower specificity compared with both previous criteria sets.

Intrinsic changes of left ventricular function in patients with Behçet disease and comparison according to systemic disease activity.

PURPOSE: Although cardiac manifestation of Behçet disease (BD) has been described in sporadic reports, its timely diagnosis remains difficult. The objective of this study was to describe early cardiac manifestations of BD. We also performed a comprehensive classification of systemic BD activity and compared their cardiac manifestations. METHODS: A prospective screening using speckle tracking echocardiography was performed in 85 patients with BD who had no history of heart disease. After excluding subjects with left ventricular (LV) ejection fraction (LVEF) <50% (n = 1), atrial fibrillation (n = 2), or inadequate echocardiographic images (n = 1), we analyzed their clinical and echocardiographic parameters including LV global longitudinal strains (GLS) and compared them with those of an age- and gender-matched control group (n = 145). Systemic BD activity was classified as minimal (Group A), controlled (Group B), and active (Group C). RESULTS: In 81 study patients (59 females, age of 51 ± 11 years), echocardiography revealed a mean LVEF of 64 ± 5% without any significant valvular dysfunction or aortic aneurysm. Although there was no difference in LVEF between the control group and the patient group, the patient group showed significant reduction in GLS (-17.1 ± 2.9% vs -20.8 ± 2.2%, P < .001). Groups A (n = 21, 26%), B (n = 47, 58%), and C (n = 13, 58%) consistently showed reduction in GLS compared with the control group. However, there was no significant difference in cardiac manifestations among these groups according to systemic disease activity. CONCLUSION: Patients with BD present intrinsic LV dysfunction despite no apparent abnormality on routine echocardiography. However, their cardiac manifestations are not proportional to systemic BD activity.

Leukocyte-specific protein 1 regulates T-cell migration in rheumatoid arthritis.

Copy number variations (CNVs) have been implicated in human diseases. However, it remains unclear how they affect immune dysfunction and autoimmune diseases, including rheumatoid arthritis (RA). Here, we identified a novel leukocyte-specific protein 1 (LSP1) deletion variant for RA susceptibility located in 11p15.5. We replicated that the copy number of LSP1 gene is significantly lower in patients with RA, which correlates positively with LSP1 protein expression levels. Differentially expressed genes in Lsp1-deficient primary T cells represent cell motility and immune and cytokine responses. Functional assays demonstrated that LSP1, induced by T-cell receptor activation, negatively regulates T-cell migration by reducing ERK activation in vitro. In mice with T-cell-dependent chronic inflammation, loss of Lsp1 promotes migration of T cells into the target tissues as well as draining lymph nodes, exacerbating disease severity. Moreover, patients with RA show diminished expression of LSP1 in peripheral T cells with increased migratory capacity, suggesting that the defect in LSP1 signaling lowers the threshold for T-cell activation. To our knowledge, our work is the first to demonstrate how CNVs result in immune dysfunction and a disease phenotype. Particularly, our data highlight the importance of LSP1 CNVs and LSP1 insufficiency in the pathogenesis of RA and provide previously unidentified insights into the mechanisms underlying T-cell migration toward the inflamed synovium in RA.

Treat-to-Target Strategy for Asian Patients with Early Rheumatoid Arthritis: Result of a Multicenter Trial in Korea.

BACKGROUND: To evaluate the therapeutic benefits of the treat-to-target (T2T) strategy for Asian patients with early rheumatoid arthritis (RA) in Korea. METHODS: In a 1-year, multicenter, open-label strategy trial, 346 patients with early RA were recruited from 20 institutions across Korea and stratified into 2 groups, depending on whether they were recruited by rheumatologists who have adopted the T2T strategy (T2T group) or by rheumatologists who provided usual care (non-T2T group). Data regarding demographics, rheumatoid factor titer, anti-cyclic citrullinated peptide antibody titer, disease activity score of 28 joints (DAS28), and Korean Health Assessment Questionnaire (KHAQ) score were obtained at baseline and after 1 year of treatment. In the T2T group, the prescription for disease-modifying antirheumatic drugs was tailored to the predefined treatment target in each patient, namely remission (DAS28 < 2.6) or low disease activity (LDA) (2.6 ≤ DAS28 < 3.2). RESULTS: Data were available for 163 T2T patients and 162 non-T2T patients. At the end of the study period, clinical outcomes were better in the T2T group than in the non-T2T group (LDA or remission, 59.5% vs. 35.8%; P < 0.001; remission, 43.6% vs. 19.8%; P < 0.001). Compared with non-T2T, T2T was also associated with higher rate of good European League Against Rheumatism response (63.0% vs. 39.8%; P < 0.001), improved KHAQ scores (-0.38 vs. -0.13; P = 0.008), and higher frequency of follow-up visits (5.0 vs. 2.0 visits/year; P < 0.001). CONCLUSION: In Asian patients with early RA, T2T improves disease activity and physical function. Setting a pre-defined treatment target in terms of DAS28 is recommended.

A phase III, multicentre, randomised, double-blind, active-controlled, parallel-group trial comparing safety and efficacy of HD203, with innovator etanercept, in combination with methotrexate, in patients with rheumatoid arthritis: the HERA study.

OBJECTIVES: To evaluate equivalence in efficacy for rheumatoid arthritis (RA) and compare the safety of the biosimilar HD203 with innovator etanercept (ETN) plus methotrexate (MTX) (ClinicalTrials.gov NCT01270997). METHODS: Patients with active RA received 25 mg HD203 or ETN subcutaneously twice-weekly with MTX for 48 weeks in a phase III, multicentre, randomised, double-blind, parallel-group design. The primary end point was the proportion of patients achieving the American College of Rheumatology 20% response (ACR20) at week 24 for per-protocol study completer set (PPS). Secondary end points included ACR response criteria, ACRn, European League against Rheumatism (EULAR) response, change in Disease Activity Score 28 (DAS28), patient-reported outcomes, safety and immunogenicity. RESULTS: Of the 294 randomised patients (HD203, n=147; ETN, n=147), 233 comprised the 24-week PPS (n=115 and 118, respectively). ACR20 at week 24 was achieved by 83.48% and 81.36% of PPS patients, respectively, demonstrating equivalent efficacy within predefined margins of ±20% (treatment difference 2.12%, 95% CI -7.65% to 11.89%). Outcomes for secondary end points were consistent with the primary efficacy findings. Groups were comparable for overall incidences of treatment-emergent (all-causality) adverse events (AEs) (HD203 113 (76.9%) vs ETN 114 (78.1%) (p=0.804)), adverse drug reactions, serious AEs and discontinuations due to AEs. Few patients (HD203, n=8; ETN, n=3) tested positive for anti-drug antibodies. CONCLUSION: The study met the primary objective of demonstrating equivalent efficacy of HD203 and ETN. HD203 was well tolerated, with safety comparable with ETN in this population of patients with RA. TRIAL REGISTRATION NUMBER: NCT01270997; Results.

A multicentre randomised controlled trial to compare the pharmacokinetics, efficacy and safety of CT-P10 and innovator rituximab in patients with rheumatoid arthritis.

OBJECTIVE: To demonstrate pharmacokinetic equivalence of CT-P10 and innovator rituximab (RTX) in patients with rheumatoid arthritis (RA) with inadequate responses or intolerances to antitumour necrosis factor agents. METHODS: In this randomised phase I trial, patients with active RA were randomly assigned (2:1) to receive 1000 mg CT-P10 or RTX at weeks 0 and 2 (alongside continued methotrexate therapy). Primary endpoints were area under the serum concentration-time curve from time zero to last quantifiable concentration (AUC0-last) and maximum serum concentration after second infusion (Cmax). Additional pharmacokinetic parameters, efficacy, pharmacodynamics, immunogenicity and safety were also assessed. Data are reported up to week 24. RESULTS: 103 patients were assigned to CT-P10 and 51 to RTX. The 90% CIs for the ratio of geometric means (CT-P10/RTX) for both primary endpoints were within the bioequivalence range of 80%-125% (AUC0-last: 97.7% (90% CI 89.2% to 107.0%); Cmax: 97.6% (90% CI 92.0% to 103.5%)). Pharmacodynamics and efficacy were comparable between groups. Antidrug antibodies were detected in 17.6% of patients in each group at week 24. CT-P10 and RTX displayed similar safety profiles. CONCLUSIONS: CT-P10 and RTX demonstrated equivalent pharmacokinetics and comparable efficacy, pharmacodynamics, immunogenicity and safety. TRIAL REGISTRATION NUMBER: NCT01534884.

Allelic heterogeneity in NCF2 associated with systemic lupus erythematosus (SLE) susceptibility across four ethnic populations.

Recent reports have associated NCF2, encoding a core component of the multi-protein NADPH oxidase (NADPHO), with systemic lupus erythematosus (SLE) susceptibility in individuals of European ancestry. To identify ethnicity-specific and -robust variants within NCF2, we assessed 145 SNPs in and around the NCF2 gene in 5325 cases and 21 866 controls of European-American (EA), African-American (AA), Hispanic (HS) and Korean (KR) ancestry. Subsequent imputation, conditional, haplotype and bioinformatic analyses identified seven potentially functional SLE-predisposing variants. Association with non-synonymous rs17849502, previously reported in EA, was detected in EA, HS and AA (P(EA) = 1.01 × 10(-54), PHS = 3.68 × 10(-10), P(AA) = 0.03); synonymous rs17849501 was similarly significant. These SNPs were monomorphic in KR. Novel associations were detected with coding variants at rs35937854 in AA (PAA = 1.49 × 10(-9)), and rs13306575 in HS and KR (P(HS) = 7.04 × 10(-7), P(KR) = 3.30 × 10(-3)). In KR, a 3-SNP haplotype was significantly associated (P = 4.20 × 10(-7)), implying that SLE predisposing variants were tagged. Significant SNP-SNP interaction (P = 0.02) was detected between rs13306575 and rs17849502 in HS, and a dramatically increased risk (OR = 6.55) with a risk allele at each locus. Molecular modeling predicts that these non-synonymous mutations could disrupt NADPHO complex assembly. The risk allele of rs17849501, located in a conserved transcriptional regulatory region, increased reporter gene activity, suggesting in vivo enhancer function. Our results not only establish allelic heterogeneity within NCF2 associated with SLE, but also emphasize the utility of multi-ethnic cohorts to identify predisposing variants explaining additional phenotypic variance ('missing heritability') of complex diseases like SLE.