Antigen-specific therapies have a long history in the treatment of allergy but have not been successful in autoimmunity. However, in the past 20 years, advances in the definition of the self-antigens that promote autoimmunity and the growing understanding of the mechanisms that maintain tolerance in health but fail in autoimmunity have led to antigen-specific approaches being considered for the treatment of autoimmune diseases. The core goal of each antigen-specific treatment approach is to remove the immune response that promotes autoimmunity whilst sparing protective responses. Approaches to antigen-specific therapy range from targeted deletion of autoreactive lymphocytes to tolerization of autoreactive T cells and active inhibition of autoimmune responses. Technologies such as vaccines, nanoparticles, cell-based therapies and gene editing are being harnessed to achieve these goals. Remaining challenges include the selection of the best antigen to target, modality and timing of administration of these therapies and the disease in which the therapies are used; overcoming these challenges will be vital to move antigen-specific therapies forward. Once established, antigen-specific therapy has the potential to be applied broadly in the area of autoimmunity.

The aetiology of polymyalgia rheumatica (PMR) is unknown. Recently, reports on cases of PMR following the coronavirus disease 2019 (COVID-19) have revived the role of infection as an aetiological or triggering factor. It is estimated that patients with PMR have manifestations of giant cell arteritis (GCA) in < 20% of cases. To date, little is known on the potential role of infectious agents in facilitating this association. Given this background, we performed a review of published literature. Our first aim was to review and discuss the relationship between PMR and infective agents. Secondly, we compared data of PMR-only patients with PMR and overlapping GCA to seek any commonalities or differences regarding the type of infectious agent in these two subgroups.

Systemic autoinflammatory diseases caused by dysregulation of the innate immunity are a known cause of recurrent fevers. We present the molecular diagnosis results of 12 children with recurrent fever, analyzing the correlation between molecular findings and clinical symptoms. No pathogenic variants confirming autoinflammatory disease were found. One child was diagnosed with SRP54 deficiency, linked to congenital neutropenia with a cyclic pattern. Variants of uncertain significance were found in 6 patients in genes associated with autoinflammatory disorders, though two lacked clinical correlation. Variants of uncertain significance in the NLRC4 gene were detected in 2 patients with periodic fever, aphthous stomatitis, pharyngitis, adenitis (PFAPA) syndrome, in the PLSG2 gene in 1 child with systemic juvenile idiopathic arthritis, and in the MEFV gene in 1 patient with syndrome of uncertain recurrent fever. COVID-19 was identified as a triggering factor in 54.5% of cases. Further research is needed to clarify the role of genetic variants and environmental factors in recurrent fevers.

Nutritional disorders are significant but often underestimated complications in patients with systemic sclerosis (SSc). The most prevalent nutritional disorders in SSc are malnutrition, affecting up to 62.5% of patients, and sarcopenia, with a frequency of up to 42%. Thus, clinical vigilance is recommended for the detection of eating disorders in SSc patients, particularly those with gastrointestinal involvement, cardiopulmonary complications, an advanced disease stage, and high disease activity. Nutritional treatment should be carefully tailored to the patients' clinical condition to ensure that it effectively addresses their specific needs. Studies focusing on enteral nutrition in SSc patients demonstrate its effectiveness in stabilizing or improving nutritional status in malnourished patients. In severe cases, parenteral nutrition offers viable options to support patient health. The findings highlight the importance of early nutritional assessment and intervention in improving patient outcomes and suggest that individualized nutritional therapy can be a critical component of comprehensive care for SSc patients.

Among adults who develop coronavirus disease 2019 (COVID-19), those with rheumatic diseases (RDs) have similar hospitalization rates compared with those without RDs. Similar comparisons are lacking in children, due to the overall rarity of COVID-19-related hospitalization in this population. We aimed to examine the risk factors for COVID-19-related hospitalization in paediatric patients with RDs.

Classic regulatory T (Treg) cells expressing CD4 and the hallmark transcription factor FOXP3 are integral to the prevention of multi-system autoimmunity. However, immune-mediated arthritis is often associated with increased numbers of Treg cells in the inflamed joints. To understand these seemingly conflicting observations, which we collectively describe as 'the Treg paradox', we provide an overview of Treg cell biology with a focus on Treg cell heterogeneity, function and dysfunction in arthritis. We discuss how the inflamed environment constrains the immunosuppressive activity of Treg cells while also promoting the differentiation of TH17-like Treg cell, exTreg cell (effector T cells that were formerly Treg cells), and osteoclastogenic Treg cell subsets that mediate tissue injury. We present a new framework to understand Treg cells in joint inflammation and define potential strategies for Treg cell-directed interventions in human inflammatory arthritis.

HLA-B*27 confers a strong risk of developing spondyloarthritis (SpA), which includes axial SpA with or without peripheral arthritis, enthesitis, acute anterior uveitis and gastrointestinal inflammation. Although no definitive mechanism has been established to explain the role of this HLA class I protein in the pathogenesis of SpA, three main hypotheses have emerged. First is the idea that self-peptides displayed by HLA-B27 resemble microorganism-derived peptides, leading to the expansion of autoreactive CD8+ T cells that trigger disease. The second and third hypotheses focus on aberrant properties of HLA-B27, including its tendency to form cell-surface dimers that can activate innate killer immunoglobulin-like receptors on CD4+ T helper 17 cells, triggering the production of pathogenic cytokines. HLA-B27 also misfolds in the endoplasmic reticulum, which can activate the unfolded protein response, increasing IL-23 expression and thereby promoting the production of type 17 cytokines. HLA-B27 misfolding in mesenchymal stem cells has also been linked to enhanced bone formation by mesenchymal stem cell-derived osteoblasts, which could contribute to structural damage in axial SpA. In this Review we summarize prevailing ideas about the role of HLA-B27 in SpA, discuss the latest developments as well as the gaps in current knowledge, and provide recommendations for future research to address these unmet needs.

Over the past two decades, the number of genetically defined autoinflammatory interferonopathies has steadily increased. Aicardi-Goutières syndrome and proteasome-associated autoinflammatory syndromes (PRAAS, also known as CANDLE) are caused by genetic defects that impair homeostatic intracellular nucleic acid and protein processing respectively. Research into these genetic defects revealed intracellular sensors that activate type I interferon production. In SAVI and COPA syndrome, genetic defects that cause chronic activation of the dinucleotide sensor stimulator of interferon genes (STING) share features of lung inflammation and fibrosis; and selected mutations that amplify interferon-α/β receptor signalling cause central nervous system manifestations resembling Aicardi-Goutières syndrome. Research into the monogenic causes of childhood-onset systemic lupus erythematosus (SLE) demonstrates the pathogenic role of autoantibodies to particle-bound extracellular nucleic acids that distinguishes monogenic SLE from the autoinflammatory interferonopathies. This Review introduces a classification for autoinflammatory interferonopathies and discusses the divergent and shared pathomechanisms of interferon production and signalling in these diseases. Early success with drugs that block type I interferon signalling, new insights into the roles of cytoplasmic DNA or RNA sensors, pathways in type I interferon production and organ-specific pathology of the autoinflammatory interferonopathies and monogenic SLE, reveal novel drug targets that could personalize treatment approaches.

Myositis-specific autoantibodies (MSAs) have become pivotal biomarkers for idiopathic inflammatory myopathies and have revolutionized understanding of the heterogeneous disease spectrum that affects both adults and children. The discovery and characterization of MSAs have substantially enhanced patient stratification based on clinical phenotype, thereby facilitating more precise diagnosis and ultimately improving management strategies. Advances in immunoassay technologies in the past 20 years have further propelled the field forward, enabling the detection of a growing repertoire of autoantibodies with high specificity and sensitivity; however, evolving research over the past decade has revealed that even within antibody-defined subsets, considerable clinical diversity exists, suggesting a broader spectrum of disease manifestations than previously acknowledged. Challenges persist, particularly among patients who are seronegative, where the failure to identify certain rare MSAs stems from the use of diverse detection methodologies and inadequate consensus-guided standardization and validation protocols. Bridging these diagnostic gaps is crucial for optimizing patient care and refining prognostic stratification in idiopathic inflammatory myopathies.

Psoriasis is a chronic inflammatory skin disease that often precedes the development of psoriatic arthritis. Advances over the past 10 years have deepened our understanding of the transition from skin inflammation to joint inflammation, revealing various phases during which genetic, environmental, and immunological factors can affect this transition. In 2023, a European Alliance of Associations for Rheumatology task force outlined key considerations for identifying individuals with subclinical disease from those with clinically stabilised disease. Discerning between subclinical psoriatic arthritis and very early disease is crucial and raises doubts and questions about when an individual transitions from being at risk to having established psoriatic arthritis. Labelling this stage as very early psoriatic arthritis rather than subclinical disease might have substantial clinical and therapeutic implications. This Viewpoint highlights the importance of precisely identifying the different stages of progression of psoriatic arthritis for timely interventions and better outcomes for patients.

To assess the association of aPL and diffuse alveolar haemorrhage (DAH) in patients with SLE by performing a systematic review and meta-analysis.

The global population is ageing and the rheumatology workforce should be prepared to take care of the inevitable complexities of ageing patients. We can learn from our colleagues and experts in geriatrics about how best to manage multimorbidity, polypharmacy, geriatric syndromes, and shifting priorities of older patients in the context of delivering care for rheumatic diseases. One approach to learning and adopting key ageing constructs within rheumatology practice is to incorporate the established Geriatric 5Ms-principles fundamental to caring for older adults. In this Series paper we discuss the 5Ms in the context of rheumatology practice (1) multicomplexity: assessing and managing multimorbidity and challenging biopsychosocial situations, (2) medications: ensuring that medications do not interfere with the other Ms, (3) mind: managing neurocognitive disorders and comorbid mental health conditions, (4) mobility: ensuring older adults can move independently and safely, and (5) what matters most: aligning care with an older adult's specific goals.

Inflammation is an important risk factor, a potential therapeutic target for cognitive decline and dementia, and an inherent feature of autoimmune and immune-mediated rheumatic diseases. The risk of cognitive impairment and dementia is increased in individuals with immune-mediated rheumatic diseases, particularly in those with cardiovascular risk factors and cardiovascular disease. Immunomodulatory medications have been associated with a reduced risk of dementia, but whether this effect is mediated through their anti-inflammatory immunomodulating properties or other mechanisms, such as cardiovascular risk reduction, is unclear. A better understanding of the role of chronic inflammation as a modifiable risk factor for cognitive performance in rheumatic diseases will help inform opportunities for the management of cognitive impairment in people with rheumatic diseases and other chronic inflammatory diseases. In this Series paper, we discuss the epidemiology, risk factors, and current evidence on the role of immunomodulatory medications in cognitive impairment and dementia in people with rheumatic diseases.

Frailty represents a dynamic multisystem state of reduced physiological reserve that increases vulnerability to adverse health outcomes. Frailty occurs prematurely in adults with immune-mediated rheumatic diseases and is emerging as an important risk factor for adverse outcomes in these conditions. In this Series paper, we present a conceptual overview of frailty and its prevalence among patients with immune-mediated rheumatic diseases. We discuss putative mechanisms of frailty relevant to these diseases, tools for frailty measurement, and potential implications of frailty assessment for clinical care. We also explore the complex inter-relationship between frailty, inflammation, and disease activity in immune-mediated rheumatic diseases. As insight is gained into the epidemiology and mechanisms of frailty among patients with immune-mediated inflammatory rheumatic diseases, the possibility of targeting frailty with an intervention that could complement standard disease-modifying therapies to prevent adverse outcomes and improve health-related quality of life becomes closer to reality.

This study aimed to conduct a comprehensive systematic literature review and meta-analysis to assess the risk and outcomes of coronavirus disease 2019 (COVID-19) in patients with rheumatoid arthritis.

Chimeric antigen receptor (CAR) T cells have recently shown remarkable promise in treating rheumatic diseases, including systemic lupus erythematosus (SLE), idiopathic inflammatory myopathies, and systemic sclerosis. Currently, there are 37 clinical trials registered for CAR T-cell therapy in rheumatic diseases and many more are being planned. Much of this enthusiasm is justifiable, but widespread adoption of CAR T-cell therapy in rheumatology faces several barriers. The trajectory of autoimmune diseases differs from malignancies and a surprisingly narrow population could be eligible for CAR T-cell therapy. Current CAR T-cell approaches rely on B-cell depletion, which has a mixed record of success for many diseases. The high cost of CAR T-cell therapy and potential safety concerns, such as cytokine release syndrome and long-term infection risks, also pose substantial challenges. Moving forward, more targeted CAR T-cell approaches, such as antigen-specific chimeric autoantibody receptors or chimeric autoantigen T-cell receptors, could offer greater efficacy and safety in treating rheumatic diseases.

Emerging evidence indicates that memory B cells are dysfunctional in systemic lupus erythematosus (SLE). They are hyporesponsive to signalling through the B cell receptor (BCR) but retain responsiveness to Toll-like receptor (TLR) and type I interferon signalling, as well as to T cell-mediated activation via CD40-CD154. Chronic exposure to immune complexes of ribonucleoprotein (RNP)-specific autoantibodies and TLR-engaging or BCR-engaging cargo is likely to contribute to this partially anergic phenotype. TLR7 or TLR8 signalling and the resulting production of type I interferon, as well as the sustained activation by bystander T cells, fuel a positive feedforward loop in memory B cells that can evade negative selection and permit preferential expansion of anti-RNP autoantibodies. Clinical trials of autologous stem cell transplantation or of B cell-targeted monoclonal antibodies and chimeric antigen receptor (CAR) T cells have correlated replenishment of the memory B cell population with relapse of SLE. Moreover, the BCR hyporesponsiveness of memory B cells might explain the failure of non-depleting B cell-targeting approaches in SLE, including BTK inhibitors and anti-CD22 monoclonal antibodies. Thus, targeting of dysfunctional memory B cells might prove effective in SLE, while also avoiding the adverse events of broad-spectrum targeting of B cell and plasma cell subsets that are not directly involved in disease pathogenesis.

Uveitis encompasses multiple different conditions that are all characterized by intra-ocular inflammation. Uveitis occurs in the context of many different rheumatological conditions and carries a substantial risk to vision. Uveitis can develop both at the early stages of rheumatic diseases, sometimes even preceding other clinical features, and at later stages of disease. Uveitis can also occur as either a direct or an indirect complication of therapies used to treat patients with rheumatic disease. Conversely, patients with uveitis of non-rheumatic aetiology sometimes require immunosuppression, a treatment option that is not readily accessible to ophthalmologists. Thus, collaborative working between rheumatologists and ophthalmologists is critical for optimal management of patients with uveitis. This Review is written with rheumatologists in mind, to assist in the care of patients with uveitis. We collate and summarize the latest evidence and best practice in the diagnosis, management and prognostication of uveitis, including future trends and research priorities.

IBM remains an enigmatic and complex muscle disorder where a deeper understanding of disease pathomechanisms and the identification of potential genetic contributors represent an unmet need. The absence of effective treatments has spurred endeavours to reassess the interplay between degeneration, including autophagy, mitochondrial dysfunction and proteasomal dysregulation, and autoimmunity. IBM is unique among the other idiopathic inflammatory myopathies owing to its molecular signature involving highly differentiated cytotoxic T cells that evade immune regulation. This has led to a resurgence of interest in the development of immunomodulatory therapy. This review discusses the potential role of cellular immunosenescence in sustaining inflammation and/or fibrotic remodelling observed in IBM and appraises the rationale for some potential therapeutic approaches to mitigate disease progression.

Developing knee osteoarthritis (OA) treatments is challenging due to assessing pain and joint structure outcomes within a highly heterogeneous disease. Lorecivivint (LOR), an intra-articular CLK/DYRK inhibitor, modulates Wnt and inflammatory pathways. This review analysis of LOR 0.07 mg trial data aims to describe the potential impact of baseline joint structure on OA pain response.