Janus kinase inhibitors and tumour necrosis factor inhibitors show a favourable safety profile and similar persistence in rheumatoid arthritis, psoriatic arthritis and spondyloarthritis: real-world data from the BIOBADASER registry.

OBJECTIVES: To compare the safety of Janus kinase inhibitors (JAKi) with that of tumour necrosis factor inhibitors (TNFi) and determine drug persistence among patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA). METHODS: We analysed data from patients included in BIOBADASER 3.0 and treated with JAKi or TNFi from 2015 to 2023 and estimated the incidence rate ratio (IRR) of adverse events and persistence. RESULTS: A total of 6826 patients were included. Of these, 52% had RA, 25% psoriatic arthritis and 23% axial SpA. Treatment was with TNFi in 86%. The mean duration of treatment was 2.2±2.0 years with TNFi versus 1.8±1.5 with JAKi. JAKis were prescribed in older patients with longer term disease, greater comorbidity and later treatment lines and more frequently as monotherapy. The IRR of all infections and gastrointestinal events was higher among patients with RA treated with JAKi. Drug persistence at 1, 2 and 3 years was 69%, 55% and 45% for TNFi and 68%, 54% and 45% for JAKi. Multivariate regression models showed a lower probability of discontinuation for JAKi (HR=0.85; 95% CI 0.78-0.92) and concomitant conventional synthetic disease-modifying antirheumatic drugs (HR=0.90; 95% CI 0.84-0.96). The risk of discontinuation increased with glucocorticoids, comorbidities, greater disease activity and later treatment lines. CONCLUSIONS: Infections, herpes zoster and gastrointestinal adverse events in patients with RA tended to be more frequent with JAKi. However, prognosis was poor in patients receiving JAKi. Persistence was similar for TNFi and JAKi, although factors associated with discontinuation differed by diagnostic group.

Tocilizumab in giant cell arteritis: differences between the GiACTA trial and a multicentre series of patients from the clinical practice.

OBJECTIVES: A potential point of concern among clinicians is whether results derived from the clinical trials can be reasonably applied or generalised to a definable group of patients seen in real world. It can be the case of the GiACTA study that is a phase III randomised controlled trial of tocilizumab (TCZ) in giant cell arteritis (GCA). To address this question, we compared the clinical features and the responses to TCZ from the GiACTA trial patients with those from a series of GCA seen in the daily clinical practice. METHODS: Comparative study of clinical features between patients from the GiACTA trial (overall n=251) and those from a multicentre series of real-world GCA patients undergoing TCZ therapy (n=134). The diagnosis of GCA in the GiACTA trial was established by the ACR modified criteria whereas in the series of real-world patients it was made by using the ACR criteria, a positive biopsy of temporal artery or the presence of imaging techniques consistent with large-vessel vasculitis in individuals who presented cranial symptoms of GCA. GiACTA trial patients received subcutaneous TCZ (162 mg every 1 or 2 weeks) whereas those from the clinical practice series were treated using standard IV dose (8 mg/kg/month) or subcutaneous (162 mg/week). RESULTS: Real-life patients undergoing TCZ were older with longer disease duration and higher values of ESR and had received conventional immunosuppressive therapy (mainly methotrexate) more commonly than those included in the GiACTA trial. Despite clinical differences, TCZ was equally effective in both GiACTA trial and clinical practice patients. However, serious infections were more commonly observed in GCA patients recruited from the clinical practice. CONCLUSIONS: Despite clinical differences with patients recruited in clinical trials, data from real-life patients confirm the efficacy of TCZ in GCA.

Polymorphisms at phase I-metabolizing enzyme and hormone receptor loci influence the response to anti-TNF therapy in rheumatoid arthritis patients.

The aim of this case-control study was to evaluate whether 47 single-nucleotide polymorphisms (SNPs) in steroid hormone-related genes are associated with the risk of RA and anti-TNF drug response. We conducted a case-control study in 3 European populations including 2936 RA patients and 2197 healthy controls. Of those, a total of 1985 RA patients were treated with anti-TNF blockers. The association of potentially interesting markers in the discovery population was validated through meta-analysis with data from DREAM and DANBIO registries. Although none of the selected variants had a relevant role in modulating RA risk, the meta-analysis of the linear regression data with those from the DREAM and DANBIO registries showed a significant correlation of the CYP3A4rs11773597 and CYP2C9rs1799853 variants with changes in DAS28 after the administration of anti-TNF drugs (P = 0.00074 and P = 0.006, respectively). An overall haplotype analysis also showed that the ESR2GGG haplotype significantly associated with a reduced chance of having poor response to anti-TNF drugs (P = 0.0009). Finally, a ROC curve analysis confirmed that a model built with eight steroid hormone-related variants significantly improved the ability to predict drug response compared with the reference model including demographic and clinical variables (AUC = 0.633 vs. AUC = 0.556; PLR_test = 1.52 × 10-6). These data together with those reporting that the CYP3A4 and ESR2 SNPs correlate with the expression of TRIM4 and ESR2 mRNAs in PBMCs (ranging from P = 1.98 × 10-6 to P = 2.0 × 10-35), and that the CYP2C9rs1799853 SNP modulates the efficiency of multiple drugs, suggest that steroid hormone-related genes may have a role in determining the response to anti-TNF drugs.KEY POINTS• Polymorphisms within the CYP3A4 and CYP2C9 loci correlate with changes in DAS28 after treatment with anti-TNF drugs.• A haplotype including eQTL SNPs within the ESR2 gene associates with better response to anti-TNF drugs.• A genetic model built with eight steroid hormone-related variants significantly improved the ability to predict drug response.

Correction: Polymorphisms at phase I-metabolizing enzyme and hormone receptor loci influence the response to anti-TNF therapy in rheumatoid arthritis patients.

The original version of this Article contained an error in the spelling of the author Ana Rodríguez-Ramos, which was incorrectly given as Ana Rodríguez Ramos. This has now been corrected in both the PDF and HTML versions of the Article.

Evaluation of a clinical pharmacogenetics model to predict methotrexate response in patients with rheumatoid arthritis.

Variability of response to treatment hinders successful management of rheumatoid arthritis (RA). Consequently, a clinical pharmacogenetics model for predicting response to methotrexate (CP-MTX) has been previously proposed that includes four clinical variables (disease activity, sex, the presence of rheumatoid factor and smoking status) and four SNPs (rs2236225, rs17602729, rs1127354, and rs2372536) in genes of the folate pathway. It showed good performance, but failed to attract attention, likely, in relation with lack of clear clinical benefit. Here, we have revised the value of the CP-MTX model directly addressing its clinical benefit by focusing on the expected benefit-cost of the predictions. In addition, our study included a much larger number of RA patients (n = 720) in MTX monotherapy than previous studies. Benefit of CP-MTX prediction was defined as the patients that would have received combination therapy as first treatment because they were correctly predicted as non-responders to MTX monotherapy. In contrast, cost of CP-MTX prediction was defined as the responder patients that were wrongly predicted as non-responders. Application of CP-MTX predictions to our patients showed a good benefit-cost relationship, with half of the 66.7% non-responders to MTX monotherapy rightly directed to alternative treatments (a benefit of 33.3%) at the cost of 8.5% wrongly predicted non-responders. These benefits-costs were consistent with reanalysis of the previously published studies. Therefore, predictions of CP-MTX showed a good benefit-cost relationship for informing MTX prescription.

Genetic variants within the TNFRSF1B gene and susceptibility to rheumatoid arthritis and response to anti-TNF drugs: a multicenter study.

BACKGROUND: Recent research suggests that genetic variants in the tumor necrosis factor receptor 2 (TNFRSF1B) gene may have an impact on susceptibility to rheumatoid arthritis (RA) and drug response. The present population-based case-control study was carried out to evaluate whether 5 tagging single-nucleotide polymorphisms (SNPs) within the TNFRSF1B gene are associated with the risk of RA and response to antitumor necrosis factor (TNF) drugs. METHODS: The study population included 1412 RA patients and 1225 healthy controls. A subset of 596 anti-TNF-naive RA patients was selected to assess the association of TNFRSF1B SNPs and drug response according to the EULAR response criteria. RESULTS: We found that carriers of the TNFRSF1Brs3397C allele had a significantly increased risk of developing RA (P=0.0006). Importantly, this association remained significant after correction for multiple testing. We also confirmed the lack of association of the TNFRSF1Brs1061622 SNP with the risk of RA in the single-SNP analysis (P=0.89), but also through well-powered meta-analyses (PDOM=0.67 and PREC=0.37, respectively). In addition, our study showed that carriers of the TNFRSF1Brs3397C/C, TNFRSF1Brs1061622G/G, and TNFRSF1Brs1061631A/A genotypes had an increased risk of having a worse response to anti-TNF drugs at the level of P less than 0.05 (P=0.014, 0.0085 and 0.028, respectively). We also observed that, according to a log-additive model, carriers of the TNFRSF1Brs3397C or TNFRSF1Brs1061622G alleles showed an increased risk of having worse response to anti-TNF medications (P=0.018 and 0.0059). However, the association of the TNFRSF1Brs1061622 SNP only reached marginal significance after correction for multiple testing according to a log-additive model (P=0.0059) and it was not confirmed through a meta-analysis (PDOM=0.12). CONCLUSION: Our results suggest that the TNFRSF1Brs3397 variant may play a role in modulating the risk of RA, but does not provide strong evidence of an impact of TNFRSF1B variants in determining response to anti-TNF drugs.

Genetic variants within immune-modulating genes influence the risk of developing rheumatoid arthritis and anti-TNF drug response: a two-stage case-control study.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disease that arises as a result of the interaction between genetic and environmental factors. A growing body of research suggests that genetic variants within immune-related genes can influence the risk of developing the disease and affect drug response. MATERIALS AND METHODS: To test this hypothesis, we carried out a comprehensive two-stage case-control study in a White population of 1239 White RA patients and 1229 healthy controls to investigate whether 49 single nucleotide polymorphisms within or near 17 immune-related genes modulate the risk of developing RA and antitumor necrosis factor (anti-TNF) drug response. RESULTS: Logistic regression analyses showed that carriers of the IL4rs2070874T and IL4rs2243250T and IL8RBrs1126580A alleles or the IL8RBrs2230054C/C genotype had a significantly increased risk of developing RA [odds ratio (OR)=1.37, 95% confidence interval (CI) 1.13-1.67, P=0.0016; OR=1.24, 95% CI 1.03-1.49, P=0.020; OR=1.23, 95% CI 1.08-1.41, P=0.002 and OR=1.19, 95% CI 1.04-1.36, P=0.01, respectively]. The association of the IL4 variants was further supported by a meta-analysis including 7150 individuals (P =0.0010), whereas the involvement of the IL8RB locus in determining the susceptibility to RA was also supported by gene-gene interaction analyses that identified significant two-locus and three-locus interaction models including IL8RB variants that act synergistically to increase the risk of the disease (P=0.014 and 0.018). Interestingly, we also found that patients harbouring the IFNGrs2069705C allele showed a significantly better response to anti-TNF drugs than those patients carrying the wild-type allele (P=0.0075). CONCLUSIONS: Our data suggest that IL4 and IL8RB loci may have a small-effect genetic impact on the risk of developing RA, whereas IFNG might be involved in modulating the response to anti-TNF drugs.

Patterns of use and dosing of tocilizumab in the treatment of patients with rheumatoid arthritis in routine clinical practice: the ACT-LIFE study.

The aim of the study was to identify and describe the patterns of use of tocilizumab in clinical practice to ensure safety and optimal management of rheumatoid arthritis (RA). This is a 12-month prospective observational study in patients with moderate or severe RA of ≥6 months' duration who have started tocilizumab after failure of at least one previous disease-modifying antirheumatic drug (DMARD) including TNF inhibitors. For some analyses, patients were categorized by the use of tocilizumab as monotherapy or in combination, and by previous use of biological therapy. Overall, 379 were evaluable (84.4 % received tocilizumab after prior biologics and 78.4 % in combination with classic DMARDs). Tocilizumab was discontinued in 68/379 (17.9 %) patients after a median of 6.7 (3.7-10.4) months, mainly due to a lack of efficacy (24/379, 6.3 %) and adverse events (23/379, 6.1 %). Of 131 temporary interruptions of tocilizumab required in 101/379 (26.6 %) patients, 81/131 (61.8 %) were related to adverse events, and in 120/131 (91.6 %) cases, tocilizumab was reintroduced at 8 mg/kg. Thirty-six tocilizumab dose reductions occurred in 34/379 (9 %) patients due to abnormal laboratory values in 20/34 (55.6 %) cases. DAS28-ESR scores decreased from baseline (5.6 ± 1.0) to week 24 (3.0 ± 1.4) and week 52 (2.7 ± 1.3). DAS28 response differed between biologics-naive and biologics-experienced patients, both at weeks 24 and 52. In clinical practice, tocilizumab is effective in RA while retaining the expected safety and tolerability profile. Tocilizumab seems to be more effective for biologics-naive patients than for biologics-experienced patients, while it proves to be similarly effective when used in combination or monotherapy.

Association of FCGR2A with the response to infliximab treatment of patients with rheumatoid arthritis.

OBJECTIVES: We aimed to assess a functional polymorphism in FCGR2A H131R, for association with the treatment response to Fc-containing inhibitors of tumor necrosis factor (TNF). METHODS: A total of 429 biologic-naive patients with rheumatoid arthritis collected in two sets (299 and 130) were treated during standard care with infliximab (INX), etanercept, or adalimumab. Response to the treatment was evaluated at 3, 6, and 12 months of follow-up as the change in the Disease Activity Score (DAS) 28 from baseline and as the response by the European League Against Rheumatism (EULAR) criteria. These variables were analyzed for association with linear and logistic regression models that included sex, inhibitors of TNF, and baseline DAS28 as covariates. RESULTS: Significant association was found between the FCGR2A H131R polymorphism and the response to treatment with INX, but not with the other two TNF inhibitors. The 131R allele was associated with a lower change in DAS28 (P=0.04-0.008 at different times) in the first set of patients and confirmed in the second group of patients (P=0.026 at 3 months of follow-up). Association was also found in the comparison between nonresponders and responders to INX by the EULAR criteria. CONCLUSION: We found an association of the FCGR2A 131R allele with poor response to INX. This finding could be of utility to understand the mechanisms behind treatment failure and contribute to biomarker panels for INX response prediction.

Observational study of optimization of biologic therapies in rheumatoid arthritis: a single-centre experience.

To analyse the effectiveness of optimization of biologics in rheumatoid arthritis (RA). It was a single-centre retrospective observational study from January 2009 to September 2012. The effectiveness of the optimization of TNF antagonists, tocilizumab and abatacept in RA was studied. Optimization included predefined dose down-titration and/or expansion of dose interval in early arthritis with sustained DAS28-ESR <2.6 and established arthritis with a sustained DAS28-ESR <3.2. Primary outcome was time to relapse defined as increase in DAS28-ESR greater than 20 % over baseline. Cox's regression analysis was performed to identify predictors of relapse. Sixty-four patients were included in the study. In the survival analysis, rates of relapse were 9.8 % at 6 months, 31.4 % at 12 months and 44.6 % at 18 months. Rates of patients with an increase in DAS28-ESR > 20 % and ≥1 inflamed joint at 6, 9 and 18 months were 1.6, 17.2 and 27.1 %, respectively. In relapsing patients, mean DAS28-ESR at relapse was 3.44 (2.94-4.79) and mean DAS28-ESR following the return to the prior dose of the biologic was 2.52 (1.42-3.21). No predictors of relapse were found in multivariate analysis. Optimization of the treatment with biologics in RA is an efficacious and safe treatment option.

Exploring candidate biomarkers for rheumatoid arthritis through cardiovascular and cardiometabolic serum proteome profiling.

Introduction: RA patients are at higher risk of cardiovascular disease, influenced by therapies. Studying their cardiovascular and cardiometabolic proteome can unveil biomarkers and insights into related biological pathways. Methods: This study included two cohorts of RA patients: newly diagnosed individuals (n=25) and those with established RA (disease duration >25 years, n=25). Both cohorts were age and sex-matched with a control group (n=25). Additionally, a longitudinal investigation was conducted on a cohort of 25 RA patients treated with methotrexate and another cohort of 25 RA patients treated with tofacitinib for 6 months. Clinical and analytical variables were recorded, and serum profiling of 184 proteins was performed using the Olink technology platform. Results: RA patients exhibited elevated levels of 75 proteins that might be associated with cardiovascular disease. In addition, 24 proteins were increased in RA patients with established disease. Twenty proteins were commonly altered in both cohorts of RA patients. Among these, elevated levels of CTSL1, SORT1, SAA4, TNFRSF10A, ST6GAL1 and CCL18 discriminated RA patients and HDs with high specificity and sensitivity. Methotrexate treatment significantly reduced the levels of 13 proteins, while tofacitinib therapy modulated the expression of 10 proteins. These reductions were associated with a decrease in DAS28. Baseline levels of SAA4 and high levels of BNP were associated to the non-response to methotrexate. Changes in IL6 levels were specifically linked to the response to methotrexate. Regarding tofacitinib, differences in baseline levels of LOX1 and CNDP1 were noted between non-responder and responder RA patients. In addition, response to tofacitinib correlated with changes in SAA4 and TIMD4 levels. Conclusion: In summary, this study pinpoints molecular changes linked to cardiovascular disease in RA and proposes candidate protein biomarkers for distinguishing RA patients from healthy individuals. It also highlights how methotrexate and tofacitinib impact these proteins, with distinct alterations corresponding to each drug's response, identifying potential candidates, as SAA4, for the response to these therapies.

Association of anti-citrullinated vimentin and anti-citrullinated α-enolase antibodies with subsets of rheumatoid arthritis.

OBJECTIVE: To determine whether the anti-citrullinated vimentin peptide 60-75 (anti-Cit-vimentin) and the immunodominant anti-citrullinated α-enolase peptide 1 (anti-CEP-1) antibodies are associated with subsets of patients with rheumatoid arthritis (RA) independently of the associations between anti-cyclic citrullinated peptide (anti-CCP) antibodies and clinical features of RA. METHODS: The 3 antibody types were quantified by enzyme-linked immunosorbent assay (ELISA) in serum samples from 521 patients with RA and 173 healthy controls of Spanish ancestry. Genotypes for HLA-DRB1 alleles and rs2476601 in PTPN22 were available for these patients and controls plus an additional 106 healthy controls. A combined analysis of the 3 antibodies was conducted using stratified contingency tables and logistic regression models. RESULTS: A differential, particularly strong, and independent association was observed between the presence of anti-Cit-vimentin antibodies and the presence of shared epitope (SE) alleles, specifically in patients carrying 2 SE alleles, and between the presence of anti- Cit-vimentin antibodies and the prevalence of joint erosion. Associations were observed between anti-CEP-1 positivity and the presence of HLA-DRB1 and PTPN22 risk alleles and their additive interaction. These associations were not accounted for by the anti-CCP status. CONCLUSION: Our results indicate that the 2 antibodies against citrullinated peptides analyzed in this study add specific information beyond that obtained with the anti-CCP status. They define subgroups of patients with RA in which genetic factors have different weight and there is an observed difference in the prevalence of erosions.

Persistence and Use of Ixekizumab in Patients with Psoriatic Arthritis in Real-World Practice in Spain. The PRO-STIP Study.

INTRODUCTION: Ixekizumab (IXE) is an IgG4-type monoclonal antibody targeting IL-17A indicated alone or in combination with methotrexate, for the treatment of active psoriatic arthritis (PsA) in adult patients with insufficient response or with intolerance to one or more disease-modifying anti-rheumatic drug (DMARD) therapy. The PRO-STIP study aimed to describe persistence, patient characteristics, treatment patterns, and effectiveness in patients with PsA receiving IXE in a real-world clinical setting in Spain. METHODS: This was an observational, multicentric, retrospective, longitudinal study in adult PsA patients who started IXE between January 2019 and December 2020, with at least 24 weeks of follow-up. A descriptive analysis of patient characteristics and treatment patterns was performed. The primary objective, treatment persistence, was estimated by Kaplan-Meier survival curve. Effectiveness was evaluated by Disease Activity in Psoriatic Arthritis (DAPSA) scores at baseline and at 12 and 24 weeks. RESULTS: Eighty-nine patients met the selection criteria (55.1% women and mean age 51.5 years). The median time from PsA diagnosis to starting IXE was 7.7 years (IQR 3.4-14.6). Prior to IXE, 95.5% patients had been treated with at least one biologic or targeted synthetic DMARD (b/tsDMARD). The observed persistence rates were 95.5%, 84.3% and 68.5% at 24, 48, and 104 weeks, respectively. The median persistence was not reached in the study period (mean persistence, 86.9 [95% CI 80.6-93.2] weeks). Twenty-eight (31.5%) patients discontinued IXE, 19 patients (21.3%) due to loss of effectiveness and two patients (2.2%) due to adverse events. In patients receiving treatment and with available effectiveness assessment (n = 24), DAPSA decreased significantly from baseline 23.7 (95% CI 19.5-27.9) to 14.8 (95% CI 10.5-19.2) at 12 weeks (p = 0.005) and 14.3 (95% CI 11.1-17.4) at 24 weeks (p = 0.004). CONCLUSIONS: PsA patients treated with IXE in a real-world setting show high treatment persistence through 104 weeks and improvements in disease activity after treatment initiation. This suggests that IXE could be an effective treatment for patients with PsA. RETROSPECTIVELY REGISTERED: Date of registration: 25th May 2021.

Assessment of anti-malondialdehyde-acetaldehyde antibody frequencies in rheumatoid arthritis with new data from two independent cohorts, meta-analysis, and meta-regression.

BACKGROUND: Autoantibodies are critical elements in RA pathogenesis and clinical assessment. The anti-malondialdehyde-acetaldehyde (anti-MAA) antibodies are potentially useful because of their claimed high sensitivity for all RA patients, including those lacking RF and anti-CCP antibodies. Therefore, we aimed to replicate these findings. METHODS: We independently attempted replication in Santiago and Barcelona using sera from 517 and 178 RA patients and 272 and 120 healthy controls, respectively. ELISA protocols for anti-MAA antibodies included five antigens (human serum albumin in three formulations, fibrinogen, and a synthetic peptide) and assays for the IgG, IgM, and IgA isotypes. We integrated our results with information found by searching the Web of Science for reports of anti-MAA antibodies in RA. The available patients (4989 in 11 sets) were included in a meta-analysis aimed at heterogeneity between studies. Factors accounting for heterogeneity were assessed with meta-regression. RESULTS: The sensitivity of anti-MAA antibodies in our RA patients was low, even in seropositive patients, with the percentage of positives below 23% for all ELISA conditions. Our results and bibliographic research showed IgG anti-MAA positive patients ranging from 6 to 92%. The extreme between-studies heterogeneity could be explained (up to 43%) in univariate analysis by sex, African ethnicity, the site of study, or recruitment from the military. The best model, including African ancestry and smoking, explained a high heterogeneity fraction (74%). CONCLUSION: Anti-MAA antibody sensitivity is extremely variable between RA patient collections. A substantial fraction of this variability cannot be attributed to ELISA protocols. On the contrary, heterogeneity is determined by complex factors that include African ethnicity, smoking, and sex.

The most reliable probe position in the ultrasonographic examination of the wrist in rheumatoid arthritis.

OBJECTIVES: This study aims to evaluate the inter-observer reliability of the ultrasonographic examination of the wrist in RA patients between 3 examiners and 3 probe positions. METHODS: Fifty-three RA patients were recruited at the University Clinical Hospital of Santiago de Compostela in Spain for ultrasonographic examination of the wrist. Ultrasonography (US) was performed on both wrists using a GE LOGIQ 9 machine, using three probe positions: Lister's Tubercle to digit II (position 1), Lister's Tubercle to digit III (position 2) and ulnocarpal (position 3), from the anatomic medial orientation. Three examiners (2 experienced ultrasonographers and 1 junior ultrasonographer) scored synovitis according to a 0-3 semiquantitative scoring system. Inter-observer reliability was expressed using the ICC (A,1). RESULTS: For grey-scale ultrasound (GSUS) the inter-observer reliability (ICC(A,1)) (single measure, agreement definition) ranged from 0.35 for the ulnocarpal joint, position 3, to 0.60 in both position 1 for the radiocarpal joint and position 2 for the inter-carpal joint. Using power Doppler ultrasound (PDUS) the inter-observer reliability (ICC(A,1)) ranged from 0.36 in position 3, to 0.52 both in position 1 and 2 for the radiocarpal joint. CONCLUSIONS: The reliability of the GSUS-examination of the wrist joints of RA patients with GSUS shows highest, moderate reliability using the anatomical landmarks Tubercle of Lister and digit III (position 2). The reliability of the PDUS examination was similar and moderate in both position 1 (Lister's Tubercle to digit II) and position 2 (Lister's Tubercle to digit III). The reliability was poorest for position 3 (the anatomic medial view of the ulnocarpal joint) in both the GSUS and PDUS examination. This study suggests that position 2 should be used in clinical trials and daily practice.

Particular association of clinical and genetic features with autoimmunity to citrullinated α-enolase in rheumatoid arthritis.

OBJECTIVE: To confirm that the presence of anti-citrullinated α-enolase peptide 1 (anti-CEP-1) antibodies identifies a subgroup of patients with rheumatoid arthritis (RA). METHODS: DNA and serum samples were obtained from 451 patients with RA and 279 healthy control subjects, all of whom were of Spanish ancestry. Antibodies to cyclic citrullinated peptide (CCP) and CEP-1 were measured by enzyme-linked immunosorbent assay. HLA-DRB1 and the R620W single-nucleotide polymorphism of PTPN22 were genotyped. RESULTS: Anti-CEP-1 and anti-CCP antibodies were observed in 26.8% and 71.2% of the patients with RA, respectively. Most of the patients (86.6%) with anti-CEP-1 antibodies also had anti-CCP antibodies. Erosive arthritis, rheumatoid factor (RF) positivity, and the presence of the HLA shared epitope (especially the DRB1*04 alleles) were disproportionately associated with the group of patients with both antibodies. In addition, evidence of a significant interaction between the shared epitope and the risk allele of PTPN22 was observed only in these patients. In contrast, the association with these clinical and genetic features was weaker in patients with anti-CCP antibodies but lacking anti-CEP-1 antibodies. These results were obtained in patients in whom the prevalence of RA risk factors differed from that in other previously studied patients. CONCLUSION: We observed that autoimmunity against citrullinated α-enolase may identify a subset of patients with a higher frequency of joint erosions and RF positivity. In addition, we confirmed the disproportionately large effect of the susceptibility alleles of HLA-DRB1 and their interaction with PTPN22 in this subset of patients. These results extend, confirm, and generalize the evidence supporting the specificity of the anti-CEP-1 antibody-positive subgroup of patients with RA among anti-CCP antibody-positive patients with RA.

ROCK inhibition with Y-27632 reduces joint inflammation and damage in serum-induced arthritis model and decreases in vitro osteoclastogenesis in patients with early arthritis.

Rheumatoid arthritis (RA) is a common chronic inflammatory disease affecting primarily peripheral joints, which is only partially controlled with current treatments. RA leads to pain, disability, deformities, and life expectancy shortening. Its pathogenesis is complex involving multiple cell types and signaling pathways that we incompletely understand. One of the pathways we have elucidated starts with WNT5A signaling and contributes to the aggressive phenotype of the RA synoviocytes through RYK-RhoA/ROCK signaling. Now, we have explored the contribution of ROCK to arthritis in vivo, using the K/BxN serum-transfer arthritis model; and to osteoclastogenesis, using the arthritis model and cells from patients with inflammatory arthritis. The mice and cells were treated with the ROCK inhibitor Y-27632 that caused a significant improvement of arthritis and reduction of osteoclastogenesis. The improvement in mouse arthritis was observed in the clinical evaluation and, histologically, in synovial inflammation, cartilage damage, bone erosion, and the abundance of multinucleated TRAP+ cells. Expression of inflammatory mediators in the arthritic joints, as assessed by real-time PCR, was also significantly reduced. The effect on bone was confirmed with in vitro assays using bone marrow precursors of arthritic mice and peripheral blood monocytes of patients with inflammatory arthritis. These assays showed dramatically reduced osteoclastogenesis and bone resorption. Overall, our findings suggest that ROCK inhibition could be part of a therapeutic strategy for RA by its dual action on inflammation and bone erosion.

Antibodies against 4 Atypical Post-Translational Protein Modifications in Patients with Rheumatoid Arthritis.

Patients with rheumatoid arthritis (RA) show autoantibodies against post-translational protein modifications (PTMs), such as anti-citrullinated protein antibodies. However, the range of recognized PTMs is unknown. Here, we addressed four PTMs: chlorination, non-enzymatic glycation, nitration, and homocysteinylation, identified as targets of atypical RA autoantibodies in studies whose protocols we have followed. The modified antigens included collagen type II, an extract of synovial proteins and a selection of peptides. We interpreted the results according to the optical density (OD) obtained in an enzyme-linked immunosorbent assay ( ELISA) with the modified antigen and the corrected OD obtained after subtracting the reactivity against the unmodified antigen. The results showed evidence of specific antibodies against glycated collagen type II, as the corrected ODs were higher in the 182 patients with RA than in the 164 healthy controls (p = 0.0003). However, the relevance of these antibodies was doubtful because the magnitude of the specific signal was small (median OD = 0.072 vs. 0.027, respectively). There were no specific antibodies against any of the other three PTMs. Therefore, our results showed that the four PTMs are not inducing a significant autoantibody response in patients with RA. These results indicated that the repertoire of PTM autoantigens in RA is restricted.

Association of the serological status of rheumatoid arthritis patients with two circulating protein biomarkers: A useful tool for precision medicine strategies.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joints and presence of systemic autoantibodies, with a great clinical and molecular heterogeneity. Rheumatoid Factor (RF) and anti-citrullinated protein antibodies (ACPA) are routinely used for the diagnosis of RA. However, additional serological markers are needed to improve the clinical management of this disease, allowing for better patient stratification and the desirable application of precision medicine strategies. In the present study, we investigated those systemic molecular changes that are associated with the RF and ACPA status of RA patients. To achieve this objective, we followed a proteomic biomarker pipeline from the discovery phase to validation. First, we performed an iTRAQ-based quantitative proteomic experiment on serum samples from the RA cohort of the Hospital of Santiago de Compostela (CHUS). In this discovery phase, serum samples from the CHUS cohort were pooled according to their RF/ACPA status. Shotgun analysis revealed that, in comparison with the double negative group (RF-/ACPA-), the abundance of 12 proteins was altered in the RF+/ACPA+ pool, 16 in the RF+/ACPA- pool and 10 in the RF-/ACPA+ pool. Vitamin D binding protein and haptoglobin were the unique proteins increased in all the comparisons. For the verification phase, 80 samples from the same cohort were analyzed individually. To this end, we developed a Multiple Reaction Monitoring (MRM) method that was employed in a comprehensive targeted analysis with the aim of verifying the results obtained in the discovery phase. Thirty-one peptides belonging to 12 proteins associated with RF and/or ACPA status were quantified by MRM. In a final validation phase, the serum levels of alpha-1-acid glycoprotein 1 (A1AG1), haptoglobin (HPT) and retinol-binding protein 4 (RET4) were measured by immunoassays in the RA cohort of the Hospital of A Coruña (HUAC). The increase of two of these putative biomarkers in the double seropositive group was validated in 260 patients from this cohort (p = 0.009 A1AG1; p = 0.003 HPT). The increased level of A1AG1 showed association with RF rather than ACPA (p = 0.023), whereas HPT showed association with ACPA rather than RF (p = 0.013). Altogether, this study has allowed a further classification of the RA seropositive patients into two novel clusters: RF+A1AG+ and ACPA+HPT+. The determination of A1AG1 and HPT in serum would provide novel information useful for RA patient stratification, which could facilitate the effective implementation of personalized medicine in routine clinical practice.

Validation of screening criteria for spondyloarthritis in patients with inflammatory bowel disease in routine clinical practice.

BACKGROUND: Spondyloarthritis (SpA) is one of the most common extraintestinal manifestations of inflammatory bowel disease (IBD). Diagnostic delay must be avoided. AIMS: We assessed the validity of SpA screening criteria (any of the following characteristics: chronic low back pain with onset before 45 years of age; inflammatory lower back pain or alternating buttock pain; arthritis; heel enthesitis; dacylitis; HLA-B27 positivity; sacroiliitis on imaging). METHODS: This was a multicenter cross-sectional observational study in IBD patients aged ≥18 years. After evaluating the SpA screening criteria, the gastroenterologists referred the participants to the rheumatologists, who determined whether the patient fulfilled the screening criteria and carried out the necessary tests for SpA diagnosis. RESULTS: 35 (11.7%) out of 300 patients were diagnosed with SpA. The combination with the best balance between sensitivity and specificity (91.4% and 72.1%, respectively, when applied by the rheumatologists; 80% and 78.9%, when applied by the gastroenterologists) for SpA screening, was fulfillment of any of the following: chronic low back pain with onset before age 45 years, inflammatory low back pain or alternating buttock pain, arthritis, or dactylitis. CONCLUSION: This is one of the first studies to validate SpA screening criteria in IBD patients in routine clinical practice.