Rheumatoid arthritis

Integrating pretest probability for rheumatoid arthritis with likelihood ratios of RF and ACPA to improve clinical utility of rheumatoid arthritis autoantibody testing

BACKGROUND AND AIMS

Rheumatoid arthritis (RA) manifests through various symptoms and systemic manifestations. Diagnosis involves serological markers like rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPA). Past studies have shown the added value of likelihood ratios (LRs) in result interpretation. LRs can be combined with pretest probability to estimate posttest probability for RA. There is a lack of information on pretest probability. This study aimed to estimate pretest probabilities for RA.

MATERIALS AND METHODS

This retrospective study included 133 consecutive RA patients and 651 consecutive disease controls presenting at a rheumatology outpatient clinic. Disease characteristics, risk factors associated with RA and laboratory parameters were documented for calculating pretest probabilities and LRs.

RESULTS

Joint involvement, erosions, morning stiffness, and positive CRP, ESR tests significantly correlated with RA. Based on these factors, probabilities for RA were estimated. Besides, LRs for RA were established for RF and ACPA and combinations thereof. LRs increased with antibody levels and were highest for double high positivity. Posttest probabilities were estimated based on pretest probability and LR.

CONCLUSION

By utilizing pretest probabilities for RA and LRs for RF and ACPA, posttest probabilities were estimated. Such approach enhances diagnostic accuracy, offering laboratory professionals and clinicians insights in the value of serological testing during the diagnostic process.

BACH1 as a key driver in rheumatoid arthritis fibroblast-like synoviocytes identified through gene network analysis

RNA-sequencing and differential gene expression studies have significantly advanced our understanding of pathogenic pathways underlying rheumatoid arthritis (RA). Yet, little is known about cell-specific regulatory networks and their contributions to disease. In this study, we focused on fibroblast-like synoviocytes (FLS), a cell type central to disease pathogenesis and joint damage in RA. We used a strategy that computed sample-specific gene regulatory networks to compare network properties between RA and osteoarthritis FLS. We identified 28 transcription factors (TFs) as key regulators central to the signatures of RA FLS. Six of these TFs are new and have not been previously implicated in RA through ex vivo or in vivo studies, and included BACH1, HLX, and TGIF1. Several of these TFs were found to be co-regulated, and BACH1 emerged as the most significant TF and regulator. The main BACH1 targets included those implicated in fatty acid metabolism and ferroptosis. The discovery of BACH1 was validated in experiments with RA FLS. Knockdown of BACH1 in RA FLS significantly affected the gene expression signatures, reduced cell adhesion and mobility, interfered with the formation of thick actin fibers, and prevented the polarized formation of lamellipodia, all required for the RA destructive behavior of FLS. This study establishes BACH1 as a central regulator of RA FLS phenotypes and suggests its potential as a therapeutic target to selectively modulate RA FLS.

CD5L induces inflammation and survival in RA-FLS through ERK1/2 MAPK pathway

OBJECTIVE

To explore the effect of CD5-like molecule (CD5L) on rheumatoid arthritis (RA) fibroblast-like synoviocytes (RA-FLS) and the relative molecular mechanism of CD5L in it.

METHODS

Recombinant protein CD5L was used to stimulate the cultured RA-FLS cells. The inflammation-related cytokines were determined by real time-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). The signal molecules and apoptosis-related molecules were detected by western blot assay (WB), and cell counting kit-8 (CCK-8) was used to detect the proliferation.

RESULTS

CD5L can increase the production of IL-6, IL-8, and TNF-α and this effect can be inhibited by signal pathway inhibitor. At the same time, CD5L activated ERK1/2 MAPK signal, inhibitor treatment can weaken the intensity of phosphorylation. In addition, CD5L can enhance the proliferation ability of RA-FLS.

CONCLUSION

CD5L induces the production of inflammatory cytokines in RA-FLS through the ERK1/2 MAPK pathway and increases cell survival.

An interdisciplinary perspective on peripheral drivers of pain in rheumatoid arthritis

Pain is one of the most debilitating symptoms of rheumatoid arthritis (RA), and yet remains poorly understood, especially when pain occurs in the absence of synovitis. Without active inflammation, experts most often attribute joint pain to central nervous system dysfunction. However, advances in the past 5 years in both immunology and neuroscience research suggest that chronic pain in RA is also driven by a variety of abnormal interactions between peripheral neurons and mediators produced by resident cells in the local joint environment. In this Review, we discuss these novel insights from an interdisciplinary neuro-immune perspective. We outline a potential working model for the peripheral drivers of pain in RA, which includes autoantibodies, resident immune and mesenchymal cells and their interactions with different subtypes of peripheral sensory neurons. We also offer suggestions for how future collaborative research could be designed to accelerate analgesic drug development.

JAK inhibitors inhibit angiogenesis by reducing VEGF production from rheumatoid arthritis-derived fibroblast-like synoviocytes

INTRODUCTION/OBJECTIVES

JAK/STAT signaling inhibition exerts therapeutic effects on angiogenesis in rheumatoid arthritis (RA). However, whether the inhibitory effect differs among JAK inhibitors because of differing selectivity is unknown. Therefore, we compared the inhibitory effects of tofacitinib, baricitinib, peficitinib, upadacitinib, and filgotinib on angiogenesis.

METHOD

RA-derived fibroblast-like synoviocytes (RA-FLS) were seeded on type I collagen gel, and human umbilical vein endothelial cells (HUVECs) were directly added. The control and aforementioned JAK inhibitors were added to the medium, followed by stimulation with interleukin (IL)-6 and soluble IL-6 receptor (sIL-6R). Each JAK inhibitor's concentration was determined based on estimated blood concentrations. The vascular endothelial growth factor (VEGF) concentration was evaluated with an enzyme-linked immunosorbent assay using the medium from the first exchange. A migration assay was performed, and HUVEC migration was evaluated using CD31 fluorescence immunostaining.

RESULTS

Hematoxylin-eosin staining showed that compared with the non-JAKi treatment group, the JAKi treatment group markedly degenerated in the sub-lining and deep lining, with decreased lymphocyte infiltration and neovascularization [Rooney's score subscale, non-JAKi vs JAKi (median, 6.5 vs 2.5, p = 0.005)]. In vitro, IL-6 and sIL-6R administration increased VEGF production from RA-FLS and promoted neovascularization in HUVECs, and JAK-inhibitor administration, which decreased VEGF production from RA-FLS and suppressed HUVEC migration, inhibited neovascularization in RA-FLS and HUVEC co-cultures.

CONCLUSIONS

The JAK inhibitors suppressed IL-6-induced angiogenesis via decreased VEGF production and HUVEC migration in RA-FLS and HUVEC co-cultures. No significant differences were observed among the JAK inhibitors, whose anti-angiogenic effect may be an important mechanism for RA treatment. Key Points • JAK inhibitors inhibit angiogenesis in RA by reducing VEGF production from RA-derived fibroblast-like synoviocytes. • Our study provides new insights into RA treatment by elucidating the anti-angiogenic effect of JAK inhibitors.

Single-cell analysis in rheumatic and allergic diseases: insights for clinical practice

Since the advent of single-cell RNA sequencing (scRNA-seq) methodology, single-cell analysis has become a powerful tool for exploration of cellular networks and dysregulated immune responses in disease pathogenesis. Advanced bioinformatics tools have enabled the combined analysis of scRNA-seq data and information on various cell properties, such as cell surface molecular profiles, chromatin accessibility and spatial information, leading to a deeper understanding of pathology. This Review provides an overview of the achievements in single-cell analysis applied to clinical samples of rheumatic and allergic diseases, including rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, allergic airway diseases and atopic dermatitis, with an expanded scope beyond peripheral blood cells to include local diseased tissues. Despite the valuable insights that single-cell analysis has provided into disease pathogenesis, challenges remain in translating single-cell findings into clinical practice and developing personalized treatment strategies. Beyond understanding the atlas of cellular diversity, we discuss the application of data obtained in each study to clinical practice, with a focus on identifying biomarkers and therapeutic targets.

Autoimmune diseases and atherosclerotic cardiovascular disease

Autoimmune diseases are associated with a dramatically increased risk of atherosclerotic cardiovascular disease and its clinical manifestations. The increased risk is consistent with the notion that atherogenesis is modulated by both protective and disease-promoting immune mechanisms. Notably, traditional cardiovascular risk factors such as dyslipidaemia and hypertension alone do not explain the increased risk of cardiovascular disease associated with autoimmune diseases. Several mechanisms have been implicated in mediating the autoimmunity-associated cardiovascular risk, either directly or by modulating the effect of other risk factors in a complex interplay. Aberrant leukocyte function and pro-inflammatory cytokines are central to both disease entities, resulting in vascular dysfunction, impaired resolution of inflammation and promotion of chronic inflammation. Similarly, loss of tolerance to self-antigens and the generation of autoantibodies are key features of autoimmunity but are also implicated in the maladaptive inflammatory response during atherosclerotic cardiovascular disease. Therefore, immunomodulatory therapies are potential efficacious interventions to directly reduce the risk of cardiovascular disease, and biomarkers of autoimmune disease activity could be relevant tools to stratify patients with autoimmunity according to their cardiovascular risk. In this Review, we discuss the pathophysiological aspects of the increased cardiovascular risk associated with autoimmunity and highlight the many open questions that need to be answered to develop novel therapies that specifically address this unmet clinical need.

Chondroitin sulfate-based microneedles for transdermal delivery of stem cell-derived extracellular vesicles to treat rheumatoid arthritis

For the non-invasive treatment of rheumatoid arthritis (RA), a chondroitin sulfate C (CSC)-based dissolving microneedles (cMN) was prepared to deliver human adipose stem cell-derived extracellular vesicles (hASC-EV) into inflamed joints. Owing to their anti-inflammatory function, the hASC-EV-bearing cMN (EV@cMN) significantly suppressed activated fibroblast-like synoviocytes (aFLS) and M1 macrophages (M1), which are responsible for the progression of RA. In addition, EV@cMN facilitated the chondrogenic differentiation of bone marrow-derived stem cells. In mice with collagen-induced arthritis, EV@cMN efficiently delivered both hASC-EV and CSC to inflamed joints. Interestingly, pro-inflammatory cytokines in the inflamed joints were remarkably downregulated by the synergistic effect of CSC and hASC-EV. Consequently, as judged from the overall clinical score and joint swelling, EV@cMN showed an outstanding therapeutic effect, even comparable to the wild-type mice, without significant adverse effects. Overall, EV@cMN might have therapeutic potential for RA by efficiently delivering CSC and hASC-EV into the inflamed joints in a non-invasive manner.

Chemokine CXCL13-CXCR5 signaling in neuroinflammation and pathogenesis of chronic pain and neurological diseases

Chronic pain dramatically affects life qualities of the sufferers. It has posed a heavy burden to both patients and the health care system. However, the current treatments for chronic pain are usually insufficient and cause many unwanted side effects. Chemokine C-X-C motif ligand 13 (CXCL13), formerly recognized as a B cell chemokine, binds with the cognate receptor CXCR5, a G-protein-coupled receptor (GPCR), to participate in immune cell recruitments and immune modulations. Recent studies further demonstrated that CXCL13-CXCR5 signaling is implicated in chronic pain via promoting neuroimmune interaction and neuroinflammation in the sensory system. In addition, some latest work also pointed out the involvement of CXCL13-CXCR5 in the pathogenesis of certain neurological diseases, including ischemic stroke and amyotrophic lateral sclerosis. Therefore, we aim to outline the recent findings in regard to the involvement of CXCL13-CXCR5 signaling in chronic pain as well as certain neurological diseases, with the focus on how this chemokine signaling contributes to the pathogenesis of these neurological diseases via regulating neuroimmune interaction and neuroinflammation. Strategies that can specifically target CXCL13-CXCR5 signaling in distinct locations may provide new therapeutic options for these neurological diseases.

Microneedles as an Emerging Platform for Transdermal Delivery of Phytochemicals

Phytochemicals, which are predominantly found in plants, hold substantial medicinal value. Despite their potential, challenges such as poor oral bioavailability and instability in the gastrointestinal tract have limited their therapeutic use. Traditional intra/transdermal drug delivery systems offer some advantages over oral administration but still suffer from issues such as limited penetration depth, slow drug release rates, and inconsistent drug absorption. In contrast, microneedles (MNs) represent a significant advancement in intra/transdermal drug delivery by providing precise control over phytochemical delivery and enhanced penetration capabilities. By circumventing skin barriers, MNs directly access dermal layers rich in blood vessels and lymphatics, thus facilitating efficient phytochemical delivery. This review extensively discusses the obstacles of traditional oral delivery and the benefits of intra/transdermal delivery routes with a particular focus on the transformative potential of MNs for phytochemical delivery. This review explores the complexities of delivering phytochemicals through intra/transdermal routes, the development and types of MNs as innovative delivery tools, and the optimal design and properties of MNs for effective phytochemical delivery. Additionally, this review examines the versatile applications of MN-mediated phytochemical delivery, including its role in administering phytophotosensitizers for photodynamic therapy, and concludes with insights into relevant patents and future perspectives.

N-(4-methoxyphenyl) quinoline-8-sulfonamide reduces the inflammatory response of fibroblast-like synoviocytes by targeting receptor (calcitonin) activity modifying protein 1 in rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is characterized by chronic inflammation of the synovium of joints. Fibroblast-like synoviocytes (FLS) play an important role in RA pathogenesis. We aimed to investigate the effect of N-(4-methoxyphenyl) quinoline-8-sulfonamide (QS-3g) on the inflammatory response of FLS and explore the potential underlying mechanisms.

METHODS

We screened and found that QS-3g exhibits the best anti-inflammatory response against FLS using the CCK8 assay. To investigate the therapeutic effects of QS-3g on K/BxN STA mice, we used H&E staining, immunofluorescence, immunohistochemistry, micro-CT, and other techniques. Additional investigations, including RNA-seq, molecular docking, and CETSA, revealed that QS-3g binds to RAMP1.

RESULTS

Among a series of 8-quinoline sulfonyl amide derivatives, QS-3g reduced the inflammatory response in TNF-α stimulated FLS, such as the release of interleukin (IL)-1β and IL-6. H&E staining and micro-CT showed that QS-3g inhibited synovial hypertrophy, inflammatory cell infiltration, and bone destruction. RNA-seq and CETSA analyses revealed the targeted inhibition of RAMP1 by QS-3g. Inhibition of RAMP1 expression could reduce IL-6 and IL-1β levels. Compared with RAMP1-si, combined administration of QS-3g and RAMP1-si reduced the TNF-α-induced inflammation in TNF-α stimulated FLS without statistically significant differences. Finally, the results of in vitro experiments showed that QS-3g could restore the balance of Gαi/Gαs by inhibiting Gαi and activating Gαs and up-regulate the expression of cAMP protein, thus inhibiting the RAMP1-mediated inflammatory response in FLS.

CONCLUSION

QS-3g could inhibit RAMP1 activity and mediate the Gαs/Gαi-cAMP pathway to reduce FLS inflammatory response. Therefore, QS-3g may serve as a novel anti-inflammatory compound for treating RA.

Short Link N Modulates Inflammasome Activity in Intervertebral Discs Through Interaction with CD14

Intervertebral disc degeneration and pain are associated with the nucleotide-binding domain, leucine-rich repeat, and pyrin domain-containing 3 (NLRP3) inflammasome activation and the processing of interleukin-1 beta (IL-1β). Activation of thehm inflammasome is triggered by Toll-like receptor stimulation and requires the cofactor receptor cluster of differentiation 14 (CD14). Short Link N (sLN), a peptide derived from link protein, has been shown to modulate inflammation and pain in discs in vitro and in vivo; however, the underlying mechanisms remain elusive. This study aims to assess whether sLN modulates IL-1β and inflammasome activity through interaction with CD14. Disc cells treated with lipopolysaccharides (LPS) with or without sLN were used to assess changes in Caspase-1, IL-1β, and phosphorylated nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB). Peptide docking of sLN to CD14 and immunoprecipitation were performed to determine their interaction. The results indicated that sLN inhibited LPS-induced NFκB and Caspase-1 activation, reducing IL-1β maturation and secretion in disc cells. A significant decrease in inflammasome markers was observed with sLN treatment. Immunoprecipitation studies revealed a direct interaction between sLN and the LPS-binding pocket of CD14. Our results suggest that sLN could be a potential therapeutic agent for discogenic pain by mitigating IL-1β and inflammasome activity within discs.

Exploration of Risk Factors for Cardiovascular Disease in Patients with Rheumatoid Arthritis: A Retrospective Study

OBJECTIVE

Patients with rheumatoid arthritis (RA) have increased mortality and morbidity rates owing to cardiovascular diseases (CVD). Timely detection of CVD in RA can greatly improve patient prognosis; however, this technique remains challenging. We aimed to investigate the risk factors for CVD incidence in patients with RA.

METHODS

This retrospective study included RA patients without CVD risk factors (n = 402), RA with CVD risk factors (n = 394), and RA with CVD (n = 201). Their data on routine examination indicators, vascular endothelial growth factor (VEGF), and immune cells were obtained from medical records. The characteristic variables between each group were screened using univariate analysis, least absolute shrinkage and selection operator (LASSO), random forest (RF), and logistic regression (LR) models, and individualized nomograms were further established to more conveniently observe the likelihood of CVD in RA.

RESULTS

Univariate analysis revealed significantly elevated levels of white blood cells (WBC), blood urea nitrogen (BUN), creatinine, creatine kinase (CK), lactate dehydrogenase (LDH), VEGF, serum total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), apolipoprotein B100 (ApoB100), and apolipoprotein E (ApoE) in RA patients with CVD, whereas apolipoprotein A1 (ApoA1) and high-density lipoprotein/cholesterol (HDL/TC) were decreased. Furthermore, the ratio of regulatory T (Treg) cells exhibiting excellent separation performance in RA patients with CVD was significantly lower than that in other groups, whereas the ratios of Th1/Th2/NK and Treg cells were significantly elevated. The LASSO, RF, and LR models were also used to identify the risk factors for CVD in patients with RA. Through the final selected indicators screened using the three machine learning models and univariate analysis, a convenient nomogram was established to observe the likelihood of CVD in patients with RA.

CONCLUSIONS

Serum lipids, lipoproteins, and reduction of Treg cells have been identified as risk factors for CVD in patients with RA. Three nomograms combining various risk factors were constructed to predict CVD occurring in patients with RA (RA with/without CVD risk factors).

Evaluation of the Turkish version of measure of activity performance of the hand (MAP-Hand) in people with rheumatoid arthritis

BACKGROUND

Assessing hand function is essential for many people with rheumatoid arthritis (RA). The Measure of Activity Performance of the Hand (MAP-Hand) allows a rapid evaluation of the hand.

OBJECTIVE

To translate the MAP-Hand into Turkish and investigate its psychometric properties.

METHOD

The MAP-Hand was translated into Turkish by using established translation guidelines. The questionnaire was pilot tested in 30 people with RA. Then, 185 adults with RA (150 women) participated in the study. Physical characteristics (age, sex, body mass index), socio-demographic information (education, employment, marital status), disease-related characteristics (RA medications, disease activity, duration of disease), hand strength (grip and pinch strengths), and patient reported outcome measures regarding pain, hand/upper extremity function, and general health status were collected. The Turkish MAP-Hand was re-administered to 109 participants in the following week.

RESULTS

The Turkish MAP-Hand was acceptable and feasible to administer, and showed excellent internal consistency (Cronbach's α = 0.952, confidence interval, CI = 0.942 to 0.962, p < .001). The unidimensionality of the Turkish MAP-Hand was confirmed by Rasch Analysis. Test-retest reliability was excellent (Intraclass Correlation Coefficient = 0.908, CI = 0.868 to 0.936, p < .001). The Turkish MAP-Hand showed moderate negative correlations with hand strength (Pearson's r between -0.511 and -0.572, p < .05), and fair to excellent positive correlations with disease activity, pain, hand/upper extremity function, and general health status (Pearson's r between 0.437 and 0.915, p < .05).

CONCLUSION

The Turkish Map-Hand demonstrated adequate psychometric properties (internal consistency, structural validity, test-retest reliability, convergent validity) supporting the utility of its use for evaluating the activity performance of the hand in people with RA.

Cytokine profiles and their correlation with clinical and blood parameters in rheumatoid arthritis and systemic lupus erythematosus

The abnormal biological activity of cytokines and their imbalance are implicated in developing rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Cytokine levels were measured in RA and SLE patients and compared to healthy controls using the Wilcoxon rank sum test and Kruskal-Wallis test. The relationship between cytokine levels and blood and clinical parameters was assessed using Spearman's correlation test. Compared to healthy controls, both RA and SLE patients exhibited elevated levels of GM-CSF, CX3CL1, IFN-α2, IL-12p70, IL-17A, TNF-α, IL-1β, and IFN-γ, which is evidence of their shared inflammatory signature. IL-2 levels were elevated exclusively in RA patients, while MCP-1 and IL-10 were uniquely increased in SLE patients. Notably, TNF-α showed the most significant increase in SLE patients. IL-4 was elevated in SLE patients with nephritis, correlating with IL-6, IL-10, sCD40L, and IL-8, suggesting B cell involvement in lupus nephritis. The negative correlation between CX3CL1 and TNF-α with HDL in RA and SLE respectively, highlights the potential association of these inflammatory markers with cardiovascular risk. These findings underscore the complex cytokine interplay in RA and SLE. CX3CL1 emerges as a potential therapeutic target for RA, while TNF-α and IL-4 show promise as therapeutic targets for SLE.

Muscle Strength Comparison in Immune-Mediated Rheumatic Disease vs Healthy Adults: A Meta-Analysis

OBJECTIVES

Patients with immune-mediated rheumatic diseases (IMRDs) often exhibit reduced muscle strength. Therefore, this review aimed to evaluate muscle strength in patients with IMRDs compared with healthy control and to summarize the relationship between low muscle strength and clinical features in patients with IMRDs.

DESIGN

Systematic review with meta-analysis of case-control studies.

SETTING AND PARTICIPANTS

Patients with IMRDs.

METHODS

A comprehensive search was conducted in the Embase, MEDLINE, Web of Science, and Cochrane databases to identify relevant studies published up to November 2023 on rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, and spondyloarthritis. Meta-analysis was performed using a random-effects model to determine the mean difference (MD) in muscle strength between patients with IMRDs and an age- and sex-matched healthy control group.

RESULTS

We identified 11,692 studies, and 760 studies were selected for screening. Ultimately, 26 studies met the inclusion criteria, composed of 2661 individuals, mostly women. The IMRDs women group had lower handgrip muscle strength (MD, -9.53; 95% CI, -11.78 to -7.28 kg) than the healthy control group, whereas the handgrip strength men groups did not differ significantly from that of the healthy control group. Similar trend was observed in lower limb muscle strength for the IMRDs women group than the healthy control group (MD, -63.10; 95% CI, -94.18 to -32.01 Nm). Four studies examined muscle strength and clinical features in rheumatoid arthritis: one associated it with age and disease activity, 2 associated it with disease duration, and 3 associated it with physical function. In systemic lupus erythematosus, only 2 studies associated low muscle strength with age, disease activity, and fatigue. No associations were found in spondyloarthritis, and none were found in systemic sclerosis.

CONCLUSIONS AND IMPLICATIONS

Patients with IMRD exhibit lower muscle strength than healthy counterparts, with low strength moderately associated with longer disease duration, worsening disease activity, and decline in physical function. Targeted interventions are crucial for preventing and managing muscle weakness in IMRDs.

Remote monitoring of patients with rheumatoid arthritis in a low disease activity state: a mixed methods evaluation across six hospitals in London, UK

OBJECTIVES

This study evaluated the scale-up of a remote monitoring service, capturing monthly Rheumatoid Arthritis Impact of Disease scores and patient-generated text messages, for patients with rheumatoid arthritis (RA; in remission or with low disease activity) attending routine outpatient clinics across six hospitals. We explored patients and staff experiences and implementation outcomes.

METHODS

A pragmatic, mixed methods approach was used, with active patient involvement throughout. We undertook a rapid review, analysed service-level data, and conducted a patient survey and patient and staff interviews, informed by the Capability, Opportunity, Motivation, Behaviour (COM-B) and Exploration, Preparation, Implementation, Sustainment (EPIS) theoretical frameworks.

RESULTS

The review included 37 articles, covering themes of patient and clinician acceptability, engagement, feasibility and clinical impact. Service-level data (n = 202) showed high levels of patient engagement with the service. The patient survey (n = 155) showed patients felt the service was easy to use, had confidence in it and felt it improved access to care. Patient interview (n = 22) findings mirrored those of the survey. Motivating factors included increased responsiveness and ease of contact with clinical teams. Views from staff interviews (n = 16) were more mixed. Some implementation barriers were specific to roll-out sites. Prioritization of staff needs was emphasized.

CONCLUSION

Patients were positive about the service and engagement was high. Staff views and engagement were more mixed. Results suggest that equal levels of patient and staff engagement are required for sustainability. These findings further our understanding of the implementation challenges to scaling remote monitoring interventions for patients with rheumatoid arthritis in routine care settings.

Analysis of synovitis patterns in early RA supports the importance of joint-specific factors

BACKGROUND

Rheumatoid arthritis (RA) is classically considered a systemic disorder, but the role of local factors in driving synovial inflammation is increasingly being recognized. These joint-specific factors may consequently modulate disease phenotype.

OBJECTIVES

Our goal was to study the spatial distribution of swelling, tenderness and erosions in a large cohort of early RA (ERA) patients, to assess for patterns of simultaneously-involved joint clusters. We also aimed to investigate the link between arthritis localization and phenotypic features such as bone erosions and response to methotrexate therapy.

METHODS

DMARD-naive patients from the ERA UCLouvain Brussels cohort were included. Forty-four joints were clinically assessed for swelling and tenderness before treatment, and 6 months later for methotrexate-treated patients. Clusters of joints were identified using Principal component analysis and Cramer's correlation coefficients. Frequency of bone erosions and joint-specific response to methotrexate were compared across different clusters.

RESULTS

452 ERA patients were included. Analysis of the spatial distribution of swelling and tenderness allowed for the identification of 3 joint clusters that showed significant simultaneous involvement: (i) MTP1-5 joints, (ii) hand joints (MCPs and PIPs), and (iii) larger joints. These clusters were associated with different susceptibility to bone erosions and distinct clinical features, but similar local response (joint swelling resolution) to methotrexate.

CONCLUSION

This is the first study investigating the spatial distribution of arthritis in a large cohort of early RA using an unbiased approach. We identify clusters of simultaneously involved joints, supporting the importance of local factors in driving synovitis in RA.

Longitudinal reciprocal association between rheumatoid arthritis and chronic obstructive pulmonary disease and mediation of inflammation

OBJECTIVES

To elucidate the longitudinal reciprocal association between RA and chronic obstructive pulmonary disease (COPD) and the mediating role of systemic inflammation in the association.

METHODS

A total of 403 045 participants from UK Biobank were enrolled in this study. A cross-lagged panel model was used to investigate the longitudinal reciprocal association between RA and COPD. Cox proportional hazards regression and logistic regression models were also conducted to examine the association between baseline RA and COPD during follow-up, and vice versa. Causal mediation analysis was then performed to explore the mediating roles of 160 systemic inflammatory biomarkers in the bidirectional association.

RESULTS

At baseline, 4755 (1.2%) and 6989 (1.7%) individuals were diagnosed with RA and COPD, respectively. After adjusting for the covariates, the result of a cross-lagged panel model revealed a bidirectional association between RA and COPD (β = 0.018, P < 0.001 for the RA→COPD path; β = 0.010, P < 0.001 for the COPD→RA path). In the non-COPD population, the risk of future COPD was increased in RA patients [Cox model: hazard ratio (HR) 1.65 (95% CI 1.50, 1.83); logistic model: odds ratio (OR) 1.85 (95% CI 1.66, 2.07)]. In the non-RA population, baseline COPD was associated with a higher risk of RA during follow-up [Cox model: HR 1.67 (95% CI 1.44, 1.92); logistic model: OR 1.70 (95% CI 1.47, 1.97)]. Five inflammatory factors mediated the RA→COPD path and CRP mediated the COPD→RA path (false discovery rate < 0.05).

CONCLUSIONS

A significant bidirectional association exists between RA and COPD and it is partially mediated by systemic inflammation.

Anemia as an indicator of a higher retention rate for tocilizumab versus tumor necrosis factor inhibitors in patients with rheumatoid arthritis from a Korean multi-center registry

Objective

To examine whether simple laboratory tests can guide selection between tocilizumab (TCZ) and tumor necrosis factor inhibitors (TNFi) in biologic-naive patients with rheumatoid arthritis (RA), by investigating their influence on drug retention.

Methods

Data of RA patients prescribed TCZ or TNFi as the initial biologics from March 2013 to December 2021 were obtained from the KOrean College of Rheumatology BIOlogics and Targeted Therapy (KOBIO) registry. Propensity score matching was performed to adjust for baseline confounding factors. Hazards of drug discontinuation for TCZ were calculated compared to those for TNFi. Interaction analyses with a Bonferroni-corrected p-value threshold were conducted to determine whether the hemoglobin level, C-reactive protein level, erythrocyte sedimentation rate, and platelet count affected the hazards of drug discontinuation.

Results

Overall, 893 patients were analyzed, of whom 315 and 578 were treated with TCZ and TNFi, respectively. The hazards of drug discontinuation in all patients were lower for TCZ than for TNFi (hazard ratio [HR] 0.53, 95% confidence interval [CI] 0.44~0.66). Notably, only the presence of anemia indicated a significant interaction (p for interaction=0.010); the HRs for drug discontinuation were 0.41 (95% CI 0.30~0.55) and 0.70 (95% CI 0.53~0.92) in the anemic and non-anemic groups, respectively. In the anemic subgroup, biologics were discontinued because of a lack of efficacy in 35.0% of TNFi initiators and 7.4% of TCZ initiators.Conclusion The drug discontinuation rate in biologic-naïve patients with RA was significantly lower for TCZ than for TNFi, particularly in those with anemia.

Prediction models incorporating second metacarpal cortical index for osteoporosis in rheumatoid arthritis: Externally validated machine learning models developed using data from the KURAMA cohort

OBJECTIVE

Osteoporosis and osteopenia are significant concerns in rheumatoid arthritis (RA), predisposing patients to fragility fractures. While dual-energy X-ray absorptiometry (DXA) is the gold standard for bone mineral density (BMD) assessment, simpler screening tools are needed. This study aims to assess the correlation between the second metacarpal cortical index (2MCI) and BMD in RA patients, and to evaluate machine learning (ML) models utilizing 2MCI and clinical parameters for predicting osteoporosis/osteopenia presence and BMD.

METHODS

Data from the KURAMA cohort (n = 302) and an external validation cohort (n = 32) were analyzed. BMD in the hip and forearm was obtained using DXA and 2MCI was calculated from plain hand X-ray. ML models were trained to predict osteoporosis/osteopenia presence and BMD using 2MCI and clinical variables and validated using external cohort.

RESULTS

2MCI correlated significantly with hip and forearm BMD. ML models incorporating 2MCI and other clinical parameters showed good performance in predicting osteoporosis/osteopenia presence and BMD. External validation demonstrated the generalizability of the models.

CONCLUSION

ML models utilizing 2MCI and clinical parameters show promise for osteoporosis screening in RA patients.

Amentoflavone Induces Ferroptosis to Alleviate Proliferation, Migration, Invasion and Inflammation in Rheumatoid Arthritis Fibroblast-like Synoviocytes by Inhibiting PIN1

Rheumatoid arthritis (RA) is a systemic autoimmune disease that is prevalent worldwide and seriously threatens human health. RA-fibroblast-like synoviocytes (FLS) play important roles in almost all aspects of RA progression. This study aimed to study the effect of Amentoflavone (AMF), a polyphenol compound derived from extracts of Selaginella tamariscina, on the abnormal biological behaviors of RA-FLS. The immortalized human RA-FLS cell line (MH7A) was treated with AMF or transfected with small interfering RNAs (siRNAs) targeting peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (PIN1). Then, cell viability was detected by CCK-8 assay. EDU staining, wound healing and transwell assays were employed to measure the capacities of MH7A cell proliferation, migration and invasion. The levels of inflammatory factors were assessed using ELISA kits. Additionally, ferroptosis was analyzed by detecting Fe2+ content, lipid reactive oxygen species (ROS) level and expression of ferroptosis-related proteins. Pull-down assay was employed to verify the targeted binding of AMF to PIN1. Further, PIN1 overexpression or ferroptosis inhibitor Ferrostatin-1 (Fer-1) addition was conducted to elucidate the regulatory mechanism of AMF on PIN1 and ferroptosis. Results revealed that AMF intervention or PIN1 knockdown inhibited the proliferation, migration, invasion and inflammation in MH7A cells. AMF facilitated lipid peroxidation and ferroptosis in MH7A cells. Moreover, AMF targeted inhibition of PIN1 expression, and PIN1 overexpression restored the promoting effect of AMF on lipid peroxidation and ferroptosis in MH7A cells. Besides, Fer-1 reversed the impacts of AMF on the abnormal biological behaviors of MH7A cells. In summary, AMF induced ferroptosis to inhibit the proliferation, migration, invasion and inflammation in RA-FLS by inhibiting PIN1, providing a promising candidate for RA treatment.

The potential role of fatigue in difficult-to-treat rheumatoid arthritis

OBJECTIVES

A subset of patients with rheumatoid arthritis (RA) who remains symptomatic after failing to multiple drugs are deemed to have "difficult-to-treat RA" (D2T RA). Fatigue is a burdensome symptom for RA patients, hindering their improvement. Our purpose was to evaluate the role of fatigue in D2T RA.

METHODS

This cross-sectional study included rheumatoid arthritis (RA) patients between 2018 and 2022, treated with biological agents or targeted synthetic disease-modifying antirheumatic drugs. D2T RA was defined attending EULAR criteria. Independent variable was fatigue (dimensions and impact) assessed by the Bristol Rheumatoid Arthritis Fatigue Multidimensional Questionnaire and Numerical Rating Scales. Covariables: sociodemographic, clinical and treatment. To identify factors independently associated to D2T RA, multivariable logistic regression was run.

RESULTS

The study included 145 patients and 38 (26.21%) developed D2T RA. D2T RA group were older, with more comorbidity and disability. D2T RA patients scored higher for global fatigue (p = 0.003), and almost for all their dimensions except for cognitive fatigue (p = 0.06) and fatigue coping (p = 0.07). Females with D2T RA showed more fatigue than those with non-D2T RA. In the adjusted models, all fatigue dimensions were associated with D2T RA: global fatigue RA (OR: 1.03; p = 0.007), physical (OR: 1.09; p = 0.008), living (OR: 1.09; p = 0.016), cognitive (OR: 1.1; p = 0.046) and emotional (OR: 1.18; p = 0.012).

CONCLUSIONS

Despite the absence of an explicit mention of fatigue in the definition of D2T RA, it appears to be associated to this outcome. Fatigue should be evaluated in a multidimensional perspective, and gender-specific differences should be considered.

A citrullinated antigenic vaccine in treatment of autoimmune arthritis

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease triggered by antigenic peptides with environmental and genetic risk factors. It has been shown that antigen-specific targeting could be a promising therapeutical strategy for RA by restoring immune tolerance to self-antigens without compromising normal immunity. Citrullination of antigens enhances antigenic properties and induces autoimmune responses. Here, we showed that citrullinated antigenic (citAg) vaccine ameliorated collagen-induced arthritis with decreased T-helper 1 (Th1) and Th17 cells, downregulated proinflammatory cytokines including interlukin-6 and tumor necrosis factor-α, and inhibited antigen recall responses. B cell receptor sequencing further revealed that citAg vaccine could dampen the dysregulated V(D)J recombination, restoring the immune repertoire. Taken together, the results demonstrated that citAg vaccine might have a therapeutic effect on RA.

Airways Abnormalities in a Prospective Cohort of Patients With Rheumatoid Arthritis

BACKGROUND

Rheumatoid arthritis (RA) affects roughly 1% of the population and commonly involves the lungs. Of lung involvement in RA, interstitial lung disease (ILD) is well known; however, airways disease in RA is relatively understudied.

RESEARCH QUESTION

What are the baseline airways abnormalities in a prospective cohort of patients with RA based on pulmonary function testing (PFT) results, high-resolution CT (HRCT) scans, and computational imaging analysis and are there associations between these abnormalities and respiratory symptoms?

STUDY DESIGN AND METHODS

In this single-center study, 188 patients with RA without a clinical diagnosis of ILD underwent HRCT imaging and PFT. Radiologists assessed HRCT scans for airway abnormalities. Computational imaging via VIDA Vision software and in-house quantitative CT imaging analysis was applied to 147 HRCT scans to quantify airway abnormalities.

RESULTS

Airways obstruction (FEV1 to FVC ratio < 0.7) was present in 20.7% of patients and was associated with older age, male sex, and higher smoking rate. Radiologists identified airway abnormalities in 61% of patients: 55% had bronchial wall thickening, 12% had bronchiectasis, and 5% had mosaic attenuation. These airways findings were associated with older age; male sex; lower FEV1, FVC, and FEV1 to FVC ratio; and higher rates of rheumatoid factor positivity. Prespecified quantitative CT scan metrics (wall thickening percentage and emphysema percentage) correlated with obstruction in PFT results and more severe respiratory symptoms, including shortness of breath and cough.

INTERPRETATION

High rates of airways abnormalities were found in this prospective RA cohort based on 3 methods of detection. Significant associations were identified between quantitative CT scan measures and respiratory symptoms. Airways disease may be an underrecognized extra-articular manifestation of RA and quantitative CT imaging may be a sensitive method to detect the clinical impact on respiratory symptoms.

Helper T Cells are Hyperactive and Contribute to the Dysregulation of Antibody Production in Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease, mediated by a complex interaction between B cells and various subsets of T cells. Dysfunction of helper T (Th) and regulatory T (Treg) cells may contribute to the breakdown of self-tolerance and the progression of autoimmune disease. In this study, we investigated the activity of Th and Treg cells on the differentiation of autologous B cells in vitro using cell cultures from the peripheral blood of healthy controls (HCs) and RA patients. The expressions of programmed death 1 (PD-1) and IL-21 were monitored as activation markers for Th cells. Unstimulated Th cells from RA patients showed remarkably higher PD-1 expression than HC samples. Stimulation of Th cells from RA patients with Staphylococcus enterotoxin B (SEB) in the presence of B cells significantly induced their PD-1 and IL-21 expression at a considerably higher level in RA compared to HCs, and Treg cells did not affect IL-21 production. When monitoring B-cell differentiation, a significantly higher frequency of plasma cells was observed, even in unstimulated samples of RA patients compared to HCs. In the SEB-stimulated co-cultures of the RA samples, plasma cell frequency and IgG production were considerably higher than in HCs and were not significantly affected by Tregs. These findings demonstrate that Th cells are constitutively active in RA, and their hyperactivity upon interaction with diseased B cells may lead to uncontrolled antibody production.

Regulating the lncRNA DSCR9/RPLP2/PI3K/AKT axis: an important mechanism of Xinfeng capsules in improving rheumatoid arthritis

Background

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic and symmetrical polyarthritis. RA patients often experience inflammatory reaction and hypercoagulable state, which together affect the self-perception of patient (SPP). Currently, inhibiting inflammation and hypercoagulable state are common treatment methods for alleviating RA symptoms. Xinfeng Capsules (XFC) has a long history of treating RA, and can effectively improve the inflammatory response and hypercoagulable state of RA. However, the potential mechanisms have not yet been determined.

Purpose and study design

This study elucidated the action mechanism of XFC in RA inflammation and hypercoagulability through the lncDSCR9/RPLP2/PI3K/AKT axis.

Results

Clinical observations indicated that there was a strong link between XFC therapy and improvements in inflammatory and coagulation biomarkers, as well as SPP among RA patients. The subsequent network pharmacology analysis results identified the PI3K/AKT signaling pathway as a potential mediator for XFC treatment of RA. Furthermore, clinical validation and sequencing results revealed that lncRNA DSCR9 expression (a gene implicated in inflammation and coagulation) was negatively correlated with clinical markers of inflammation and coagulation, while positively correlated with SF-36 indicators. Notably, XFC treatment remarkably upregulated lncRNA DSCR9 expression and downregulated PI3K and AKT expressions, showing opposite expression trends to the untreated cases.The regulatory effect of XFC on the lncRNA DSCR9/RPLP2/PI3K/AKT axis in RA was investigated using techniques such as RNA pull-down assay, Western blot analysis, RT-PCR, and EdU assay. Moreover, the administration of the PI3K/AKT agonist RMH can counteract the effects of XFC on p-PI3K, p-AKT, inflammation, and hypercoagulability, reinforcing the role of pathway. Finally, animal studies utilizing HE staining and transmission electron microscopy (TEM) demonstrated that XFC notably decreased PI3K and AKT expressions in adjuvant-induced arthritis (AA) rats, mitigated inflammation and hypercoagulability, and enhanced the ultrastructure of synovial cells. These findings underscored the potential mechanisms of XFC in the treatment of RA.

Conclusion

Regulating the lncRNA DSCR9/RPLP2/PI3K/AKT axis may be an important mechanism by which XFC improved RA inflammatory response and hypercoagulable state.

Similarities and differences between osteoarthritis and rheumatoid arthritis: insights from Mendelian randomization and transcriptome analysis

BACKGROUND

Osteoarthritis (OA) and rheumatoid arthritis (RA) are often difficult to distinguish in the early stage of the disease. The purpose of this study was to explore the similarities and differences between the two diseases through Mendelian randomization (MR) and transcriptome analysis.

METHODS

We first performed a correlation analysis of phenotypic data from genome-wide association studies (GWAS) of OA and RA. Then, we performed functional and pathway enrichment of differentially expressed genes in OA, RA, and normal patients. The infiltration of immune cells in arthritis was analyzed according to gene expression. Finally, MR analysis was performed with inflammatory cytokines and immune cells as exposures and arthritis as the outcome. The same and different key cytokines and immune cells were obtained by the two analysis methods.

RESULTS

GWAS indicated that there was a genetic correlation between OA and RA. The common function of OA and RA is enriched in their response to cytokines, while the difference is enriched in lymphocyte activation. T cells are the main immune cells that differentiate between OA and RA. MR analysis further revealed that OA is associated with more protective cytokines, and most of the cytokines in RA are pathogenic. In addition, CCR7 on naive CD4 + T cell was positively correlated with OA. SSC-A on CD4 + T cell was negatively correlated with RA, while HLA DR on CD33- HLA DR + was positively correlated with RA.

CONCLUSION

Our study demonstrated the similarities and differences of immune inflammation between OA and RA, allowing us to better understand these two diseases.

The Contribution of Macrophage Plasticity to Inflammatory Arthritis and Their Potential as Therapeutic Targets

Inflammatory arthritis are common chronic inflammatory autoimmune diseases characterised by progressive, destructive inflammation of the joints leading to a loss of function and significant comorbidities; importantly, there are no cures and only 20% of patients achieve drug-free remission for over 2 years. Macrophages play a vital role in maintaining homeostasis, however, under the wrong environmental cues, become drivers of chronic synovial inflammation. Based on the current "dogma", M1 macrophages secrete pro-inflammatory cytokines and chemokines, promoting tissue degradation and joint and bone erosion which over time lead to accelerated disease progression. On the other hand, M2 macrophages secrete anti-inflammatory mediators associated with wound healing, tissue remodelling and the resolution of inflammation. Currently, four subtypes of M2 macrophages have been identified, namely M2a, M2b, M2c and M2d. However, more subtypes may exist due to macrophage plasticity and the ability for repolarisation. Macrophages are highly plastic, and polarisation exists as a continuum with diverse intermediate phenotypes. This plasticity is achieved by a highly amenable epigenome in response to environmental stimuli and shifts in metabolism. Initiating treatment during the early stages of disease is important for improved prognosis and patient outcomes. Currently, no treatment targeting macrophages specifically is available. Such therapeutics are being investigated in ongoing clinical trials. The repolarisation of pro-inflammatory macrophages towards the anti-inflammatory phenotype has been proposed as an effective approach in targeting the M1/M2 imbalance, and in turn is a potential therapeutic strategy for IA diseases. Therefore, elucidating the mechanisms that govern macrophage plasticity is fundamental for the success of novel macrophage targeting therapeutics.

Evaluation of liver parenchyma with shear wave elastography in patients with rheumatoid arthritis receiving disease-modifying antirheumatic drug therapy

BACKGROUND

Methotrexate (MTX) and leflunomide (LEF) play fundamental roles in rheumatoid arthritis (RA) treatment and require proper monitoring of side effects. Concerns about MTX/LEF-related liver fibrosis (LF) in patients with RA remain unclear. This study investigated liver stiffness using two-dimensional shear wave elastography (2D-SWE) in RA patients undergoing disease-modifying antirheumatic drug (DMARD) therapy. Moreover, 2D-SWE was employed to evaluate the correlations between liver stiffness, cumulative MTX and LEF doses and risk factors for substantial LF.

METHODS

We recruited 222 participants from the Department of Rheumatology. The participants were divided into healthy controls (n = 78) and patients with RA (n = 144). Pearson's correlation analysis was performed to assess the correlations between liver stiffness and the cumulative dose of MTX/LEF and other clinical and laboratory variables.

RESULTS

The mean elasticity modulus was 4.79 ± 0.92 kPa, excluding the presence of significant fibrosis. Mean 2D-SWE values were significantly lower in healthy controls than in RA treated with MTX and LEF. The cut-off ≥3.8 kPa 2D-SWE values with the sensitivity of 86.1%, specifity of 83.3%. 2D-SWE values were not significantly different across the strata of the cumulative MTX subgroups.

CONCLUSIONS

MTX and LEF increase liver stiffness but may be considered low risk for the development of LF.

IĸBζ as a Central Modulator of Inflammatory Arthritis Pathogenesis

OBJECTIVE

Current therapies targeting individual factors in inflammatory arthritis show variable efficacy, often requiring treatment with combinations of drugs, and are associated with undesirable side effects. NF-ĸB is critical for the production and function of most inflammatory cytokines. However, given its essential role in physiologic processes, targeting NF-ĸB is precarious. Hence, identifying pathways downstream of NF-ĸB that selectively govern the expression of inflammatory cytokines in inflammatory arthritis would be advantageous. We have previously identified IĸBζ as a unique inflammatory signature of NF-ĸB that controls the transcription of inflammatory cytokines only under pathologic conditions while sparing physiologic NF-ĸB signals.

METHODS

We generated mice harboring myeloid, lymphoid, and global deletion of Nfkbiz (the gene encoding IĸBζ). These models were subjected to serum transfer-induced arthritis. Additionally, pharmacologic inhibitors of IĸBζ were injected intraperitonially. Joint swelling, microcomputed tomography, immunohistochemistry, flow cytometry, and cytokine measurements were conducted using synovial tissue samples.

RESULTS

Global deletion of Nfkbiz or depletion of neutrophils (vastly IĸBζ+ cells) reduced inflammatory synovial cells and increased anti-inflammatory and regenerative synovial cells, plummeted expression of inflammatory factors and ameliorated experimental mouse inflammatory arthritis. Further, expression of immune responsive gene-1, the enzyme responsible for itaconate production, was increased in synovial cells. Accordingly, the itaconate derivative dimethyl itaconate (DI) inhibited IĸBζ-mediated inflammatory factors. Further, in silico screen identified 8-hydroxyquinoline (HQ) as a putative inhibitor of IĸBζ not affecting physiologic NF-ĸB activity. Congruently, systemic administration of either DI or HQ inhibited joint swelling and damage.

CONCLUSION

Our study positions IĸBζ as an inflammation-specific target for therapeutic consideration in rheumatoid arthritis because its inhibition spares the beneficial functions of NF-ĸB.

Association between IL-6, miRNA-146a, MALAT1 genetic polymorphisms and risk of rheumatoid arthritis

Aim: This study aimed to investigate the associations between single nucleotide polymorphisms (SNPs) of IL-6 (-174G/C), microRNA146a (rs2910164C/G) and MALAT1 (rs619586A/G) and susceptibility to rheumatoid arthritis (RA) in Egyptians.Methods: SNPs were genotyped in 101 RA patients and 104 controls. Expression levels were evaluated either by Enzyme-linked immunosorbent assay (ELISA) for IL-6 or quantitative real-time PCR (qRT-PCR) for miR-146a and MALAT1.Results: IL-6-174 GC (OR = 3.422) genotype, IL-6-174 C allele (OR = 2.565), miR-146a (rs2910164) CG (OR = 2.190) and MALAT1 (rs619586) AA (OR = 4.125) genotypes and A allele (OR = 6.122) could be considered as risk factors for RA. An increase in the expression of IL-6, miR-146a and MALAT1 was detected in RA patients, which was independent of any SNP.Conclusion: SNPs of IL-6, miR-146a and MALAT1were linked to RA predisposition in Egyptians.

The promise of Synovial Joint-on-a-Chip in rheumatoid arthritis

Rheumatoid arthritis (RA) affects millions of people worldwide, but there are limited drugs available to treat it, so acquiring a more comprehensive comprehension of the underlying reasons and mechanisms behind inflammation is crucial, as well as developing novel therapeutic approaches to manage it and mitigate or forestall associated harm. It is evident that current in vitro models cannot faithfully replicate all aspects of joint diseases, which makes them ineffective as tools for disease research and drug testing. Organ-on-a-chip (OoC) technology is an innovative platform that can mimic the microenvironment and physiological state of living tissues more realistically than traditional methods by simulating the spatial arrangement of cells and interorgan communication. This technology allows for the precise control of fluid flow, nutrient exchange, and the transmission of physicochemical signals, such as bioelectrical, mechanical stimulation and shear force. In addition, the integration of cutting-edge technologies like sensors, 3D printing, and artificial intelligence enhances the capabilities of these models. Here, we delve into OoC models with a particular focus on Synovial Joints-on-a-Chip, where we outline their structure and function, highlighting the potential of the model to advance our understanding of RA. We integrate the actual evidence regarding various OoC models and their possible integration for multisystem disease study in RA research for the first time and introduce the prospects and opportunities of the chip in RA etiology and pathological mechanism research, drug research, disease prevention and human precision medicine. Although many challenges remain, OoC holds great promise as an in vitro model that approaches physiology and dynamics.

Effects of exogenous deoxyribonuclease I in collagen antibody-induced arthritis

BACKGROUND

Rheumatoid arthritis (RA) is associated with a high concentration of extracellular DNA (ecDNA). This could be a consequence of the inflammation, but the ecDNA could also be involved in the unknown etiopathogenesis of RA. Clearance of ecDNA is hypothesized to prevent the development of RA. This study aimed to analyze the effects of exogenous deoxyribonuclease I (DNase I) administration in an animal model of RA.

METHODS

The collagen antibody-induced arthritis (CAIA) model of RA was induced in adult female DBA/1J mice. CAIA mice were treated with saline or DNase I (10 mg/kg) every 12 h for the whole duration of the experiment. Arthritic scores were assessed. Paw volume and temperature were assessed using a plethysmometer and a thermal camera, respectively. Plasma ecDNA and its subcellular origin were analyzed using fluorometry and real-time PCR. DNase activity was quantified with single radial enzyme diffusion method.

RESULTS

The CAIA model was successfully induced as proved by a higher volume, temperature and the overall arthritis score in comparison to controls. The administration of DNase I resulted in a nearly two-fold increase in serum DNase activity. Still, it did affect neither plasma ecDNA, nor the arthritis score or other measures of joint inflammation.

CONCLUSION

Our results suggest that exogenous DNase I does not prevent the development of CAIA in mice. Whether this is true for other animal models of arthritis or clinical RA requires further research. EcDNA does not seem to be involved in the pathogenesis of CAIA. Additional studies are also needed to elucidate the role of ecDNA in the development of RA, focusing especially on its origin and inhibition of ecDNA release.

Bridging the Diagnostic Gap for Hypermobile Ehlers-Danlos Syndrome and Hypermobility Spectrum Disorders: Evidence of a Common Extracellular Matrix Fragmentation Pattern in Patient Plasma as a Potential Biomarker

Diagnosing hypermobile Ehlers-Danlos syndrome (hEDS) and hypermobility spectrum disorders (HSD), common overlapping multisystemic conditions featuring symptomatic joint hypermobility, is challenging due to lack of established causes and diagnostic tools. Currently, the 2017 diagnostic criteria for hEDS are used, with non-qualifying cases classified as HSD, although the distinction remains debated. We previously showed extracellular matrix (ECM) disorganization in both hEDS and HSD dermal fibroblasts involving fibronectin (FN), type I collagen (COLLI), and tenascin (TN), with matrix metalloproteinase-generated fragments in conditioned media. Here, we investigated these fragments in patient plasma using Western blotting across diverse cohorts, including patients with hEDS, HSD, classical EDS (cEDS), vascular EDS (vEDS), rheumatoid arthritis (RA), psoriatic arthritis (PsA), and osteoarthritis (OA), and healthy donors, uncovering distinctive patterns. Notably, hEDS/HSD displayed a shared FN and COLLI fragment signature, supporting their classification as a single disorder and prompting reconsideration of the hEDS criteria. Our results hold the promise for the first blood test for diagnosing hEDS/HSD, present insights into the pathomechanisms, and open the door for therapeutic trials focused on restoring ECM homeostasis using an objective marker. Additionally, our findings offer potential biomarkers also for OA, RA, and PsA, advancing diagnostic and therapeutic strategies in these prevalent joint diseases.

Efficacy of a cognitive-behavioral digital therapeutic on psychosocial outcomes in rheumatoid arthritis: randomized controlled trial

Cognitive behavioral therapy improves psychosocial outcomes in rheumatoid arthritis (RA), but access is limited. We conducted a randomized controlled trial to evaluate the efficacy of a cognitive-behavioral digital therapeutic, reclarit, on psychosocial outcomes in adult RA patients with impaired health-related quality of life. Participants were randomized to reclarit plus treatment as usual (TAU) or TAU plus educational and informational material (active control). The primary outcome was SF-36 mental (MCS) and physical (PCS) component summary scores at 3 months, with additional assessments at 6 months. reclarit significantly improved SF-36 MCS scores compared to control (mean difference 3.3 [95% CI 0.7, 5.9]; p = 0.014), with high user satisfaction and sustained improvements at 6 months. Depression, anxiety, fatigue, and social/work functioning also improved significantly, while SF-36 PCS, pain, and disability scores did not differ. In conclusion, reclarit offers immediate, effective, evidence-based and personalized psychological support for RA patients.

ARID5B is a negative modulator of IL-6 production in rheumatoid arthritis synovial fibroblasts

Recent single-cell RNA-sequencing analysis of rheumatoid arthritis (RA) synovial tissues revealed the heterogeneity of RA synovial fibroblasts (SFs) with distinct functions such as high IL-6 production. The molecular mechanisms responsible for high IL-6 production will become a promising drug target of RASFs to treat RA. In this study, we performed siRNA screening of 65 transcription factors (TFs) differentially expressed among RASF subsets to identify TFs involved in IL-6 production. The siRNA screening identified 7 TFs including ARID5B, a RA risk gene, that affected IL-6 production. Both long and short isoforms of ARID5B were expressed and negatively regulated by TNF-α in RASFs. The siRNA knockdown and lentiviral overexpression of long and short isoforms of ARID5B revealed that the long isoform suppressed IL-6 production stimulated with TNF-α. eQTL analysis using 58 SFs demonstrated that RA risk allele, rs10821944, in intron 4 of the ARID5B gene had a trend of eQTL effects to the expression of long isoform of ARID5B in SFs treated with TNF-α. ARID5B was found to be a negative modulator of IL-6 production in RASFs. The RA risk allele of ARID5B intron may cause high IL-6 production, suggesting that ARID5B will become a promising drug target to treat RA.

Targeting Therapeutic Windows for Rheumatoid Arthritis Prevention

Rheumatoid arthritis (RA) is a worldwide public health problem. Interventions to delay or prevent the onset of RA have attracted much attention in recent years, and researchers are now exploring various prevention strategies. At present, there is still no unified consensus for RA prevention, but targeting therapeutic windows and implementing interventions for at-risk individuals are extremely important. Due to the limited number of clinical trials on pharmacologic interventions, further studies are needed to explore and establish optimal intervention regimens and effective measures to prevent progression to RA. In this review, we introduce the RA disease process and risk factors, and present research on the use of both Western and Chinese medicine from clinical perspectives regarding RA prevention. Furthermore, we describe several complete and ongoing clinical studies on the use of Chinese herbal formulae for the prevention of RA.

Effects of interleukin-6 signal inhibition on Treg subpopulations and association of Tregs with clinical outcomes in rheumatoid arthritis

OBJECTIVES

Anti-IL-6 receptor antibodies are clinically efficacious in the management of RA with an associated increase in Tregs; however, the role of functional Treg subsets has yet to be clarified. This study aimed to evaluate how functional Treg subsets are altered by IL-6 receptor blockade and to analyse the relationship between these Treg subsets and the clinical outcome of RA.

METHODS

We collected frozen peripheral blood mononuclear cells (PBMCs) from 40 patients with RA who started tocilizumab (TCZ) with or without MTX and 11 healthy controls (HCs). We fractionated Tregs with flow cytometry based on markers of phenotype and function and measured the proportions of detailed Treg subsets sequentially from baseline to week 52.

RESULTS

The proportions of resting Tregs (rTregs) and rTregs+activated Tregs (aTregs) were significantly lower in RA patients at baseline than in HCs. The proportions of all those CD127low Tregs, rTregs, aTregs and rTregs+aTregs were significantly increased with TCZ treatment. In patients treated with TCZ without MTX, rTreg were increased. Patients with an increase in the proportion of rTregs at week 12 had significantly less arthritis flares during the observation period.

CONCLUSIONS

Blocking the IL-6 receptor with TCZ increased the proportion of rTregs, a functional Treg subpopulation. Patients with an early increase in rTregs showed a favourable treatment course and this increase in rTregs may reflect molecular remission induced by IL-6 signal inhibition.

Food safety assessment and 28-day toxicity study of the synbiotic medical food consortium SBD121

The human gut microbiome plays a crucial role in immune function. The synbiotic consortium or Defined Microbial Assemblage™ (DMA™) Medical Food product, SBD121, consisting of probiotic microbes and prebiotic fibers was designed for the clinical dietary management of rheumatoid arthritis. A 28-day repeated administration study was performed to evaluate the oral toxicity of SBD121 in male and female rats (age/weight at study start: 60 days/156-264 g) administered levels of 0, 4.96 x 1010, 2.48 x 1011, or 4.96 x 1011 colony forming units (CFU)/kg-bw. No treatment related changes were observed in ophthalmological effects, mortality, morbidity, general health and clinical observations, urinalysis, hematology, serum chemistry, absolute or relative organ weights, gross necropsy, or histopathology. A significant decrease in body weight was reported in females in the low and high-concentration groups, which corresponded in part with a significant decrease in food consumption. Results of the functional observation battery indicated front grip strength was significantly greater in the high-concentration males compared to the controls; however, this effect was not considered adverse. Based on these findings, the administration of the Medical Food SBD121 to male and female rats has a no-observable adverse effect level (NOAEL) at the highest level tested of 4.96 x 1011 CFU/kg-bw.

Auto-immuno-deficiency syndromes

Autoimmune diseases constitute a broad, heterogenous group with many diverse and often overlapping symptoms. Even so, they are traditionally classified as either systemic, rheumatic diseases or organ-directed diseases. Several theories exist about autoimmune diseases, including defective self-recognition, altered self, molecular mimicry, bystander activation and epitope spreading. While there is no consensus about these theories, it is generally accepted that genetic, pre-disposing factors in combination with environmental factors can result in autoimmune disease. The relative contribution of genetic and environmental factors varies between diseases, as does the significance of individual contributing factors within related diseases. Among the genetic factors, molecules involved in antigen (Ag) recognition, processing, and presentation stand out (e.g., MHC I and II) together with molecules involved in immune signaling and regulation of cellular interactions (i.e., immuno-phenotypes). Also, various immuno-deficiencies have been linked to development of autoimmune diseases. Among the environmental factors, infections (e.g., viruses) have attracted most attention, but factors modulating the immune system have also been the subject of much research (e.g., sunlight and vitamin D). Multiple sclerosis currently stands out due to a very strong and proven association with Epstein-Barr virus infection, notably in cases of late infection and in cases of EBV-associated mononucleosis. Thus, a common picture is emerging that both systemic and organ-directed autoimmune diseases may appropriately be described as auto-immuno-deficiency syndromes (AIdeSs), a concept that emphasizes and integrates existing knowledge on the role of immuno-deficiencies and chronic infections with development of overlapping disease syndromes with variable frequencies of autoantibodies and/or autoreactive T cells. This review integrates and exemplifies current knowledge on the interplay of genetically determined immuno-phenotypes and chronic infections in the development of AIdeSs.

Automated multi-scale computational pathotyping (AMSCP) of inflamed synovial tissue

Rheumatoid arthritis (RA) is a complex immune-mediated inflammatory disorder in which patients suffer from inflammatory-erosive arthritis. Recent advances on histopathology heterogeneity of RA synovial tissue revealed three distinct phenotypes based on cellular composition (pauci-immune, diffuse and lymphoid), suggesting that distinct etiologies warrant specific targeted therapy which motivates a need for cost effective phenotyping tools in preclinical and clinical settings. To this end, we developed an automated multi-scale computational pathotyping (AMSCP) pipeline for both human and mouse synovial tissue with two distinct components that can be leveraged together or independently: (1) segmentation of different tissue types to characterize tissue-level changes, and (2) cell type classification within each tissue compartment that assesses change across disease states. Here, we demonstrate the efficacy, efficiency, and robustness of the AMSCP pipeline as well as the ability to discover novel phenotypes. Taken together, we find AMSCP to be a valuable cost-effective method for both pre-clinical and clinical research.

Towards understanding the role of nanomedicine in targeting TNFR2 in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by inflammation of the synovium and progressive joint destruction which significantly affects both quality of life and socioeconomic status. Admittedly, various treatments are available, but they are usually accompanied by various side effects, from mild to severe, and potentially with adverse events. Tumour necrosis factor-alpha (TNF-α) plays a crucial role in the pathophysiology of RA. It promotes inflammatory, apoptosis and necroptosis via TNF receptor-1 (TNFR1) but elicit anti-inflammatory effects via TNFR2. Herein, targeting TNFR2 has gained attention in RA studies. Understanding the role of nanomedicine in modulating TNFR2 signalling may be the instrument in development of RA therapies. Nanotechnology has made a significant progress in treating various conditions of diseases since its inception. Due to this, nanomedicine has emerged as a promising therapeutics approach for RA. Recent studies have demonstrated the potential of nanomedicine in RA theranostics, combining therapy and diagnostics for improved treatment outcomes. Owing to the challenges and advancements in the field of nanotechnology, nanoparticles are seen as an applicable candidate in the treatment of RA. In this review, we provide an overview of the role of nanomedicine in targeting TNFR2 for the treatment of RA and highlight the limitations of current therapies as well as the potential of nanocarriers with controlled drug release and active targeting abilities.

Yin-Yang: two sides of extracellular vesicles in inflammatory diseases

The concept of Yin-Yang, originating in ancient Chinese philosophy, symbolizes two opposing but complementary forces or principles found in all aspects of life. This concept can be quite fitting in the context of extracellular vehicles (EVs) and inflammatory diseases. Over the past decades, numerous studies have revealed that EVs can exhibit dual sides, acting as both pro- and anti-inflammatory agents, akin to the concept of Yin-Yang theory (i.e., two sides of a coin). This has enabled EVs to serve as potential indicators of pathogenesis or be manipulated for therapeutic purposes by influencing immune and inflammatory pathways. This review delves into the recent advances in understanding the Yin-Yang sides of EVs and their regulation in specific inflammatory diseases. We shed light on the current prospects of engineering EVs for treating inflammatory conditions. The Yin-Yang principle of EVs bestows upon them great potential as, therapeutic, and preventive agents for inflammatory diseases.

Machine learning prediction and explanatory models of serious infections in patients with rheumatoid arthritis treated with tofacitinib

BACKGROUND

Patients with rheumatoid arthritis (RA) have an increased risk of developing serious infections (SIs) vs. individuals without RA; efforts to predict SIs in this patient group are ongoing. We assessed the ability of different machine learning modeling approaches to predict SIs using baseline data from the tofacitinib RA clinical trials program.

METHODS

This analysis included data from 19 clinical trials (phase 2, n = 10; phase 3, n = 6; phase 3b/4, n = 3). Patients with RA receiving tofacitinib 5 or 10 mg twice daily (BID) were included in the analysis; patients receiving tofacitinib 11 mg once daily were considered as tofacitinib 5 mg BID. All available patient-level baseline variables were extracted. Statistical and machine learning methods (logistic regression, support vector machines with linear kernel, random forest, extreme gradient boosting trees, and boosted trees) were implemented to assess the association of baseline variables with SI (logistic regression only), and to predict SI using selected baseline variables using 5-fold cross-validation. Missing values were handled individually per prediction model.

RESULTS

A total of 8404 patients with RA treated with tofacitinib were eligible for inclusion (15,310 patient-years of total follow-up) of which 473 patients reported SIs. Amongst other baseline factors, age, previous infection, and corticosteroid use were significantly associated with SI. When applying prediction modeling for SI across data from all studies, the area under the receiver operating characteristic (AUROC) curve ranged from 0.656 to 0.739. AUROC values ranged from 0.599 to 0.730 in data from phase 3 and 3b/4 studies, and from 0.563 to 0.643 in data from ORAL Surveillance only.

CONCLUSIONS

Baseline factors associated with SIs in the tofacitinib RA clinical trial program were similar to established SI risk factors associated with advanced treatments for RA. Furthermore, while model performance in predicting SI was similar to other published models, this did not meet the threshold for accurate prediction (AUROC > 0.85). Thus, predicting the occurrence of SIs at baseline remains challenging and may be complicated by the changing disease course of RA over time. Inclusion of other patient-associated and healthcare delivery-related factors and harmonization of the duration of studies included in the models may be required to improve prediction.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00147498; NCT00413660; NCT00550446; NCT00603512; NCT00687193; NCT01164579; NCT00976599; NCT01059864; NCT01359150; NCT02147587; NCT00960440; NCT00847613; NCT00814307; NCT00856544; NCT00853385; NCT01039688; NCT02187055; NCT02831855; NCT02092467.

Gelsolin alleviates rheumatoid arthritis by negatively regulating NLRP3 inflammasome activation

Despite numerous biomarkers being proposed for rheumatoid arthritis (RA), a gap remains in our understanding of their mechanisms of action. In this study, we discovered a novel role for gelsolin (GSN), an actin-binding protein whose levels are notably reduced in the plasma of RA patients. We elucidated that GSN is a key regulator of NLRP3 inflammasome activation in macrophages, providing a plausible explanation for the decreased secretion of GSN in RA patients. We found that GSN interacts with NLRP3 in LPS-primed macrophages, hence modulating the formation of the NLRP3 inflammasome complex. Reducing GSN expression significantly enhanced NLRP3 inflammasome activation. GSN impeded NLRP3 translocation to the mitochondria; it contributed to the maintenance of intracellular calcium equilibrium and mitochondrial stability. This maintenance is crucial for controlling the inflammatory response associated with RA. Furthermore, the exacerbation of arthritic symptoms in GSN-deficient mice indicates the potential of GSN as both a diagnostic biomarker and a therapeutic target. Moreover, not limited to RA models, GSN has demonstrated a protective function in diverse disease models associated with the NLRP3 inflammasome. Myeloid cell-specific GSN-knockout mice exhibited aggravated inflammatory responses in models of MSU-induced peritonitis, folic acid-induced acute tubular necrosis, and LPS-induced sepsis. These findings suggest novel therapeutic approaches that modulate GSN activity, offering promise for more effective management of RA and a broader spectrum of inflammatory conditions.

RNA N6-methyladenosine modification in arthritis: New insights into pathogenesis

The commonest type of eukaryotic RNA modification, N6-methyladenosine (m6A), has drawn increased scrutiny in the context of pathological functioning as well as relevance in determination of RNA stability, splicing, transportation, localization, and translation efficiency. The m6A modification plays an important role in several types of arthritis, especially osteoarthritis and rheumatoid arthritis. Recent studies have reported that m6A modification regulates arthritis pathology in cells, such as chondrocytes and synoviocytes via immune responses and inflammatory responses through functional proteins classified as writers, erasers, and readers. The aim of this review was to highlight recent advances relevant to m6A modification in the context of arthritis pathogenesis and detail underlying molecular mechanisms, regulatory functions, clinical applications, and future perspectives of m6A in arthritis with the aim of providing a foundation for future research directions.

Long-term safety and efficacy of anti-TNF multivalent VHH antibodies ozoralizumab in patients with rheumatoid arthritis

OBJECTIVES

This study aimed to evaluate the long-term safety and efficacy profiles of ozoralizumab in patients with rheumatoid arthritis (RA) from the OHZORA, NATSUZORA and HOSHIZORA trials.

METHODS

This study conducted an integrated analysis of the three trials. Patients who completed the OHZORA trial with concomitant treatment of ozoralizumab and methotrexate (MTX) or the NATSUZORA trial without MTX were eligible to participate in the long-term extension HOSHIZORA trial. Safety assessment was performed in the safety analysis set, and the incidence rate per 100 person-year (PY) was calculated for a summary of adverse events (AEs) and AEs of special interests (AESIs). The efficacy was analysed in terms of disease activity index response rates and functional remission.

RESULTS

The OHZORA and NATSUZORA trials enrolled 521 patients, of whom 401 patients entered the HOSHIZORA trial and 279 completed the long-term extension treatment with a mean treatment duration of 200 weeks and total exposure of 1419.34 PY in all enrolled patients. Of the patients, 96.9% demonstrated ≥1 AEs, which is mostly mild to moderate. One death was observed, but no conspicuous AEs emerged and no specific concerns in AESIs were found through the long-term administration. The efficacy assessment revealed the maintained American College of Rheumatology response rates of 20%, 50%, and 70% during the trials.

CONCLUSION

This integrated analysis revealed no new safety concerns, and the efficacy was maintained in patients with RA under long-term ozoralizumab administration.

TRIAL REGISTRATION NUMBER

jRCT2080223971, jRCT2080223973, NCT04077567.

Therapeutic potential of probiotics in gut microbial homeostasis and Rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by inflammation and joint damage. Existing treatment options primarily focus on managing symptoms and slowing disease progression, often with side effects and limitations. The gut microbiome, a vast community of microorganisms present in the gastrointestinal tract, plays a crucial role in health and disease. Recent research suggests a bidirectional relationship between the gut microbiome and RA, highlighting its potential as a therapeutic option. This review focuses on the interaction between the gut microbiome and RA development, by discussing how dysbiosis, an imbalance in gut bacteria, can contribute to RA through multiple mechanisms such as molecular mimicry, leaky gut, and metabolic dysregulation. Probiotics, live microorganisms with health benefits, are emerging as promising tools for managing RA. They can prevent the negative effects of dysbiosis by displacing harmful bacteria, producing anti-inflammatory metabolites like short-chain fatty acids (SCFA), Directly influencing immune cells, and modifying host metabolism. animal and clinical studies demonstrate the potential of probiotics in improving RA symptoms and disease outcomes. However, further research is needed to optimize probiotic strains, dosages, and treatment protocols for personalized and effective management of RA. This review summarizes the current understanding of the gut microbiome and its role in RA and discusses future research directions. In addition to the established role of gut dysbiosis in RA, emerging strategies like fecal microbiota transplantation, prebiotics, and postbiotics offer exciting possibilities. However, individual variations in gut composition necessitate personalized treatment plans. Long-term effects and clear regulations need to be established. Future research focusing on metagenomic analysis, combination therapies, and mechanistic understanding will unlock the full potential of gut microbiome modulation for effective RA management.