OMERACT systemic lupus erythematosus domain survey.

BACKGROUND: Since the development of the OMERACT Systemic Lupus Erythematosus (SLE) Core Outcome Set (COS) in 1998, many new SLE domains have been identified and measures developed, creating a need to update the SLE COS. To revisit the 1998 SLE COS and research agenda domains, and generate new candidate domains, we conducted this study of patients with SLE and collaborators. OBJECTIVE: (1) To evaluate existing candidate SLE domains for inclusion in the SLE COS. (2) To generate additional candidate SLE domains for COS consideration. (3) To engage SLE collaborators, including patients, in developing the updated SLE COS. METHODS: The OMERACT SLE Working Group's steering committee developed a survey to assess the importance of candidate SLE domains and generate additional domains for consideration towards the SLE COS. Patients with SLE followed at the University of Toronto Lupus Clinic (patient group) and members of the OMERACT SLE Working Group (collaborator group) were invited to complete the survey between August 2022 and February 2023. RESULTS: A total of 175 patients were invited and 100 completed the survey. Of 178 collaborators invited, 145 completed the survey. Patients tended to prioritize life-impact domains while collaborators prioritized clinical domains. Both patients and collaborators recommended additional domains to those included in the 1998 SLE COS and research agenda. CONCLUSION: The domain inclusion and importance results demonstrate that patients and collaborators prioritize different domains, so capturing the perspectives of both groups is essential to ensure a holistic assessment of SLE. The results of the study identify domains that already have a high level of agreement for potential inclusion in the SLE COS, domains that require further explanation, and novel domains that warrant consideration.

Unraveling immune cell heterogeneity in autoimmune arthritis: insights from single-cell RNA sequencing.

Single-cell RNA sequencing (scRNA-seq) has transformed our understanding of immune-mediated arthritis, which comprises rheumatoid arthritis and spondyloarthritis. This review outlines the key findings and advancements in scRNA-seq studies focused on the pathogenesis of autoimmune arthritis and its clinical application. In rheumatoid arthritis, scRNA-seq has elucidated the heterogeneity among synovial fibroblasts and immune cell subsets in inflammatory sites, offering insights into disease mechanisms and the differences in treatment responses. Various studies have identified distinct synovial fibroblast subpopulations, such as THY1+ inflammatory and THY1- destructive fibroblasts. Furthermore, scRNA-seq has revealed diverse T cell profiles in the synovium, including peripheral helper T cells and clonally expanded CD8+ T cells, shedding light on potential therapeutic targets and predictive markers of treatment response. Similarly, in spondyloarthritis, particularly psoriatic arthritis and ankylosing spondylitis, scRNA-seq studies have identified distinct cellular profiles associated with disease pathology. Challenges such as cost and sample size limitations persist, but collaborative efforts and utilization of public databases hold promise for overcoming these obstacles. Overall, scRNA-seq emerges as a powerful tool for dissecting cellular heterogeneity and driving precision medicine in immune-mediated arthritis.

An autoimmune transcriptional circuit drives FOXP3+ regulatory T cell dysfunction.

Autoimmune diseases, among the most common disorders of young adults, are mediated by genetic and environmental factors. Although CD4+FOXP3+ regulatory T cells (Tregs) play a central role in preventing autoimmunity, the molecular mechanism underlying their dysfunction is unknown. Here, we performed comprehensive transcriptomic and epigenomic profiling of Tregs in the autoimmune disease multiple sclerosis (MS) to identify critical transcriptional programs regulating human autoimmunity. We found that up-regulation of a primate-specific short isoform of PR domain zinc finger protein 1 (PRDM1-S) induces expression of serum and glucocorticoid-regulated kinase 1 (SGK1) independent from the evolutionarily conserved long PRDM1, which led to destabilization of forkhead box P3 (FOXP3) and Treg dysfunction. This aberrant PRDM1-S/SGK1 axis is shared among other autoimmune diseases. Furthermore, the chromatin landscape profiling in Tregs from individuals with MS revealed enriched activating protein-1 (AP-1)/interferon regulatory factor (IRF) transcription factor binding as candidate upstream regulators of PRDM1-S expression and Treg dysfunction. Our study uncovers a mechanistic model where the evolutionary emergence of PRDM1-S and epigenetic priming of AP-1/IRF may be key drivers of dysfunctional Tregs in autoimmune diseases.

Effects of cyclophosphamide administration on ovarian dysfunction in pediatric patients with connective tissue diseases: A systematic scoping review.

OBJECTIVE: This systematic scoping review assess the effect of cyclophosphamide (CY) administration during childhood on ovarian function in patients with juvenile-onset connective tissue diseases. METHODS: A MEDLINE database search was conducted using terms related to CY, juvenile-onset connective tissue diseases, and ovarian function. Studies were included if they met specific criteria. RESULTS: The search, conducted on 28 November 2023, yielded 3328 references. After a two-stage screening process, six observational studies on systemic lupus erythematosus patients were included. All studies had a high risk of confounding bias, as none adjusted for confounding variables. Two studies assessing clinical ovarian dysfunction found no clear difference between CY and non-CY groups. However, statistical differences were observed in hormonal profiles. Decreased ovarian reserve was more frequent in CY-exposed patients. Two studies showed significantly higher follicle-stimulating hormone (FSH) levels in the CY group, while one showed a trend towards higher FSH levels without statistical significance. CONCLUSION: This review suggested that CY use in childhood may not conclusively have clinically significant effects on ovarian function. Further investigation needed on CY's effect on hormonal levels, fertility, and pregnancy outcomes.

Association Between Proton Pump Inhibitors and the Risk of Intestinal Behçet Disease.

OBJECTIVE: This study aimed to investigate the association between proton pump inhibitor (PPI) use and the incidence of intestinal Behçet disease (BD) in patients with BD. METHODS: A retrospective cohort study was conducted at The University of Tokyo Hospital, including patients with BD diagnosed between April 2005 and November 2023. Cox models and Kaplan-Meier analyses were used to evaluate hazard ratios (HRs) and cumulative incidence of intestinal BD, respectively. Secondary analyses were performed to assess the duration and dose-response relationship of PPI use. RESULTS: Among 194 patients with BD, 25.3% developed intestinal BD during a mean follow-up of 12 years. PPI users had a significantly higher incidence of intestinal BD compared to nonusers (adjusted HR 2.48, 95% CI 1.38-4.47, P = 0.002), with a confirmed duration/dose-dependent relationship. The cumulative incidence of intestinal BD was markedly elevated in PPI users (log-rank P < 0.001). The result was similar to that in the propensity score-matched cohort. CONCLUSION: This study demonstrates a significant association between PPI use and increased incidence of intestinal BD in patients with BD. Caution in prescribing PPIs for patients with BD is warranted due to the potential risk of severe complications associated with intestinal BD.

The muscle tissue transcriptome of idiopathic inflammatory myopathy reflects the muscle damage process by monocytes and presence of skin lesions.

OBJECTIVE: To investigate transcriptomic and immunophenotypic features of muscle specimens from patients with idiopathic inflammatory myopathy (IIM). METHODS: Bulk RNA-sequencing was performed on muscle biopsy samples from 16 patients with dermatomyositis (DM) and 9 patients with polymyositis (PM). Seven tested positive for anti-aminoacyl t-RNA synthetase antibodies in the DM patients (ARS-DM). We conducted weighted gene coexpression network analysis (WGCNA), differentially expressed gene (DEG) analysis, and gene set variation analysis (GSVA) to assess contributions of specific pathways. Cell proportions in muscle specimens were estimated using a deconvolution approach. RESULTS: WGCNA revealed significant positive correlations between serum creatine kinase (CK) levels and gene modules involved in cellular respiration, phagocytosis, and oxidative phosphorylation (OXPHOS). Significant positive correlations were also observed between CK levels and proportions of CD16-positive and -negative monocytes and myeloid dendritic cells. Notably, DM patients demonstrated enrichment of complement and interferon-α and -γ pathway genes compared to those with PM. Furthermore, ARS-DM demonstrated a higher proportion of Th1 cells and DEGs related to OXPHOS. Additionally, serum Krebs von den Lungen-6 levels correlated with gene modules associated with extracellular matrix and transforming growth factor-ß signaling pathway. CONCLUSION: Our study highlights a significant involvement of monocytes in muscle damage and delineates pathological differences among IIM subtypes. DM was characterized by complement, interferon-α and -γ signaling, whilst ARS-DM was associated with OXPHOS. Distinctive gene expression variations in muscle specimens suggest that different pathologic mechanisms underlie muscle damage in each IIM phenotype.

A Novel De Novo Variant in KCNH5 in a Patient with Refractory Epileptic Encephalopathy.

We herein report a novel de novo KCNH5 variant in a patient with refractory epileptic encephalopathy. The patient exhibited seizures at 1 year and 7 months old, which gradually worsened, leading to a bedridden status. Brain magnetic resonance imaging (MRI) showed cerebral atrophy and cerebellar hypoplasia. A trio whole-exome sequence analysis identified a de novo heterozygous c.640A>C, p.Lys214Gln variant in KCNH5 that was predicted to be deleterious. Recent studies have linked KCNH5 to various epileptic encephalopathies, with many patients showing normal MRI findings. The present case expands the clinical spectrum of the disease, as it is characterized by severe neurological prognosis, cerebral atrophy, and cerebellar hypoplasia.

Unveiling the dynamics of B lymphocytes in systemic lupus erythematosus patients treated with belimumab through longitudinal single-cell RNA sequencing.

OBJECTIVES: Unraveling the mechanisms underlying treatment response for targeted therapeutics in systemic lupus erythematosus (SLE) patients is challenging due to the limited understanding of diverse responses of circulating immune cells, particularly B cells. We investigated B lymphocyte dynamics during anti-BAFF treatment, utilizing longitudinal single-cell transcriptome data. METHODS: We conducted single-cell RNA sequencing on PBMCs in four Korean SLE patients before and after belimumab treatment at the following time points: 2 weeks, 1, 3, 6, and 12 months. RESULTS: Analyzing over 73 000 PBMCs, we identified 8 distinct subsets of B cells and plasmablasts and analyzed dynamic changes within these cell subsets: initial declines in naive and transitional B cells followed by an increase at three months, contrasted by an initial increase and subsequent decrease in memory B cells by the third month. Meanwhile, plasmablasts exhibited a consistent decline throughout treatment. B cell activation pathways, specifically in naive and memory B cells, were downregulated during the third and sixth months. These findings were validated at the protein level throughout the first four weeks of treatment using flow cytometry. Comparative analysis with bulk transcriptome data from 22 Japanese SLE patients showed increased NR4A1 expression six months post-belimumab treatment, indicating its role in restricting self-reactive B cells, thereby contributing to the biological responses of anti-BAFF treatment. CONCLUSION: The observed B cell dynamics provided insights into the immunological mechanisms underlying the therapeutic effects of anti-BAFF in SLE patients. Furthermore, it underscores the need for research in predicting drug responses based on immune profiling.

Repression of SMAD3 by STAT3 and c-Ski induces conventional dendritic cell differentiation.

A pleiotropic immunoregulatory cytokine, TGF-ß, signals via the receptor-regulated SMADs: SMAD2 and SMAD3, which are constitutively expressed in normal cells. Here, we show that selective repression of SMAD3 induces cDC differentiation from the CD115+ common DC progenitor (CDP). SMAD3 was expressed in haematopoietic cells including the macrophage DC progenitor. However, SMAD3 was specifically down-regulated in CD115+ CDPs, SiglecH- pre-DCs, and cDCs, whereas SMAD2 remained constitutive. SMAD3-deficient mice showed a significant increase in cDCs, SiglecH- pre-DCs, and CD115+ CDPs compared with the littermate control. SMAD3 repressed the mRNA expression of FLT3 and the cDC-related genes: IRF4 and ID2. We found that one of the SMAD transcriptional corepressors, c-SKI, cooperated with phosphorylated STAT3 at Y705 and S727 to repress the transcription of SMAD3 to induce cDC differentiation. These data indicate that STAT3 and c-Ski induce cDC differentiation by repressing SMAD3: the repressor of the cDC-related genes during the developmental stage between the macrophage DC progenitor and CD115+ CDP.

Egr2 drives the differentiation of Ly6Chi monocytes into fibrosis-promoting macrophages in metabolic dysfunction-associated steatohepatitis in mice.

Metabolic dysfunction-associated steatohepatitis (MASH), previously called non-alcoholic steatohepatitis (NASH), is a growing concern worldwide, with liver fibrosis being a critical determinant of its prognosis. Monocyte-derived macrophages have been implicated in MASH-associated liver fibrosis, yet their precise roles and the underlying differentiation mechanisms remain elusive. In this study, we unveil a key orchestrator of this process: long chain saturated fatty acid-Egr2 pathway. Our findings identify the transcription factor Egr2 as the driving force behind monocyte differentiation into hepatic lipid-associated macrophages (hLAMs) within MASH liver. Notably, Egr2-deficiency reroutes monocyte differentiation towards a macrophage subset resembling resident Kupffer cells, hampering hLAM formation. This shift has a profound impact, suppressing the transition from benign steatosis to liver fibrosis, demonstrating the critical pro-fibrotic role played by hLAMs in MASH pathogenesis. Long-chain saturated fatty acids that accumulate in MASH liver emerge as potent inducers of Egr2 expression in macrophages, a process counteracted by unsaturated fatty acids. Furthermore, oral oleic acid administration effectively reduces hLAMs in MASH mice. In conclusion, our work not only elucidates the intricate interplay between saturated fatty acids, Egr2, and monocyte-derived macrophages but also highlights the therapeutic promise of targeting the saturated fatty acid-Egr2 axis in monocytes for MASH management.

Epigenetic targets of Janus kinase inhibitors are linked to genetic risks of rheumatoid arthritis.

BACKGROUND: Current strategies that target cytokines (e.g., tumor necrosis factor (TNF)-α), or signaling molecules (e.g., Janus kinase (JAK)) have advanced the management for allergies and autoimmune diseases. Nevertheless, the molecular mechanism that underpins its clinical efficacy have largely remained elusive, especially in the local tissue environment. Here, we aimed to identify the genetic, epigenetic, and immunological targets of JAK inhibitors (JAKis), focusing on their effects on synovial fibroblasts (SFs), the major local effectors associated with destructive joint inflammation in rheumatoid arthritis (RA). METHODS: SFs were activated by cytokines related to inflammation in RA, and were treated with three types of JAKis or a TNF-α inhibitor (TNFi). Dynamic changes in transcriptome and chromatin accessibility were profiled across samples to identify drug targets. Furthermore, the putative targets were validated using luciferase assays and clustered regularly interspaced short palindromic repeat (CRISPR)-based genome editing. RESULTS: We found that both JAKis and the TNFi targeted the inflammatory module including IL6. Conversely, specific gene signatures that were preferentially inhibited by either of the drug classes were identified. Strikingly, RA risk enhancers for CD40 and TRAF1 were distinctively regulated by JAKis and the TNFi. We performed luciferase assays and CRISPR-based genome editing, and successfully fine-mapped the single causal variants in these loci, rs6074022-CD40 and rs7021049-TRAF1. CONCLUSIONS: JAKis and the TNFi had a direct impact on different RA risk enhancers, and we identified nucleotide-resolution targets for both drugs. Distinctive targets of clinically effective drugs could be useful for tailoring the application of these drugs and future design of more efficient treatment strategies.

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.

Individual and population-level variability in HLA-DR associated immunogenicity risk of biologics used for the treatment of rheumatoid arthritis.

Hypothesis: While conventional in silico immunogenicity risk assessments focus on measuring immunogenicity based on the potential of therapeutic proteins to be processed and presented by a global population-wide set of human leukocyte antigen (HLA) alleles to T cells, future refinements might adjust for HLA allele frequencies in different geographic regions or populations, as well for as individuals in those populations. Adjustment by HLA allele distribution may reveal risk patterns that are specific to population groups or individuals, which current methods that rely on global-population HLA prevalence may obscure. Key findings: This analysis uses HLA frequency-weighted binding predictions to define immunogenicity risk for global and sub-global populations. A comparison of assessments tuned for North American/European versus Japanese/Asian populations suggests that the potential for anti-therapeutic responses (anti-therapeutic antibodies or ATA) for several commonly prescribed Rheumatoid Arthritis (RA) therapeutic biologics may differ, significantly, between the Caucasian and Japanese populations. This appears to align with reports of differing product-related immunogenicity that is observed in different populations. Relevance to clinical practice: Further definition of population-level (regional) and individual patient-specific immunogenic risk profiles may enable prescription of the RA therapeutic with the highest probability of success to each patient, depending on their population of origin and/or their individual HLA background. Furthermore, HLA-specific immunogenicity outcomes data are limited, thus there is a need to expand HLA-association studies that examine the relationship between HLA haplotype and ATA in the clinic.

Disease-modifying antirheumatic drug selection in Japanese patients with rheumatoid arthritis treated with biologics or JAK inhibitors without methotrexate: A retrospective hospital-based administrative claims database study.

OBJECTIVES: We evaluated the medication selection and clinical characteristics of rheumatoid arthritis patients who started treatment with/without methotrexate (MTX) (using biologic disease-modifying antirheumatic drugs or Janus kinase inhibitors instead) in Japan. METHODS: Using a Japanese hospital-based administrative claims database, rheumatoid arthritis patients who received treatment [abatacept (ABA), interleukin-6 receptor inhibitor, tumor necrosis factor inhibitor, or Janus kinase inhibitor] between 1 January 2015 and 31 December 2019 were enrolled. RESULTS: Overall, 19,301 patients were included (10,530 receiving MTX; 8771 not receiving MTX within 60 days of the first treatment). Mean ages at diagnosis were 60.7 and 65.9 years in the MTX and non-MTX groups, respectively (P < .0001). The non-MTX group had higher proportions of patients with Charlson Comorbidity Index ≥1 (P < .0001) and higher comorbidity rates. ABA was the most frequently used drug among patients with infectious/parasitic, circulatory, and respiratory diseases at baseline. Interleukin-6 receptor inhibitor had the highest use rate among patients with neoplasms; blood, gastrointestinal, and genitourinary diseases; and abnormal clinical/laboratory findings. ABA had the highest persistence probability from 6 months onward. CONCLUSIONS: MTX is used less frequently among older Japanese rheumatoid arthritis patients or those with comorbidities. In such patients, ABA is the most frequently used drug, followed by interleukin-6 receptor inhibitor, when MTX is not used at treatment start.

Machine learning-driven immunophenotypic stratification of mixed connective tissue disease corroborating the clinical heterogeneity.

OBJECTIVES: To stratify patients with mixed connective tissue disease (MCTD) based on their immunophenotype. METHODS: We analyzed the immunophenotype and transcriptome of 24 immune cell subsets from patients with MCTD, systemic lupus erythematosus (SLE), idiopathic inflammatory myopathy (IIM), and systemic sclerosis (SSc) from our functional genome database, ImmuNexUT (https://www.immunexut.org/). MCTD patients were stratified by employing machine learning models including Random Forest, trained by immunophenotyping data from SLE, IIM, and SSc patients. Transcriptomes were analyzed with gene set variation analysis (GSVA) and clinical features of MCTD subgroups were compared. RESULTS: This study included 215 patients, including 22 patients with MCTD. Machine learning models, constructed to classify SLE, IIM, and SSc patients based on immunophenotyping, were applied to MCTD patients, resulting in 16 classified as SLE-immunophenotype and 6 as non-SLE-immunophenotype. Among MCTD patients, patients with the SLE-immunophenotype had higher proportions of Th1 cells [2.85% (interquartile range (IQR) 1.54-3.91) vs 1.33% (IQR 0.99-1.74) p= 0.027] and plasmablasts [6.35% (IQR 4.17-17.49) vs 2.00% (IQR 1.20-2.80) p= 0.010]. Notably, the number of SLE-related symptoms was higher in patients with the SLE-immunophenotype [2.0 (IQR 1.0-2.0) vs 1.0 (IQR1.0-1.0) p= 0.038]. Moreover, GSVA scores of interferon-α and -γ responses were significantly higher in patients with the SLE-immunophenotype in central memory CD8+ T cells, while hedgehog signalling was higher in non-SLE-immunophenotype patients in 5 cell subsets. CONCLUSION: This study describes the stratification of MCTD patients based on immunophenotyping, suggesting the presence of distinct immunological processes behind the clinical subtypes of MCTD.

Baricitinib for anti-melanoma differentiation-associated protein 5 antibody-positive dermatomyositis-associated interstitial lung disease: a case series and literature review on Janus kinase inhibitors for the disease.

Anti-melanoma differentiation-associated protein 5 antibody-positive dermatomyositis (anti-MDA5-DM) is frequently complicated by progressive interstitial lung disease (ILD), the prognosis of which is poor, and management is a major challenge. We treated three patients with anti-MDA5-DM-associated ILD (anti-MDA5-DM-ILD) using the Janus kinase (JAK) inhibitor, baricitinib, which improved lung opacities and saved two patients. We reviewed 6 patients with anti-MDA5-DM-ILD who had been treated with tofacitinib at our institution. Five of the patients survived, although discontinuation of tofacitinib due to complications was frequently observed. In addition, a literature search of patients with anti-MDA5-DM-ILD who were treated with JAK inhibitors yielded 21 articles involving 79 cases. All patients except one were treated with tofacitinib, and the survival rate was 75.9%. Although not statistically confirmed, the deceased patients tended to be older and had higher ferritin levels. A total of 92 complications were observed, 11 of which resulted in JAK inhibitor discontinuation. Cytomegalovirus reactivation comprised a substantial percentage of all complications and of those patients who required JAK inhibitor discontinuation. Five cases with fatal infective complications were also observed. While tofacitinib has been proposed to be a therapeutic option for anti-MDA5-DM-ILD, other JAK inhibitors, including baricitinib, are a treatment option. Further investigation is warranted to optimize treatment of anti-MDA5-DM-ILD.

Characteristics of anti-melanoma differentiation associated gene 5 antibody-positive dermatomyositis with thrombotic microangiopathy.

OBJECTIVES: Anti-melanoma differentiation associated gene 5 antibody (anti-MDA5 Ab)-positive dermatomyositis (DM) is a representative of rapidly progressive interstitial pneumonia. However, its association with thrombotic microangiopathy (TMA), characterized by thrombocytopenia, haemolytic anaemia, and organ dysfunction, has not been defined. This study aimed to elucidate the characteristics of anti-MDA5 Ab-positive DM accompanied by TMA. METHODS: We reviewed our hospital records from November 2009 to September 2022. We included patients in accordance with the 2017 European League Against Rheumatism/American College of Rheumatology classification criteria and the criteria of Bohan and Peter. TMA was diagnosed according to the criteria for transplantation-associated TMA proposed by the International Working Group. RESULTS: This study enrolled a total of 26 anti-MDA5 Ab-positive DM patients, four of whom developed TMA. The patients with TMA had an increased urine protein/creatinine ratio. In addition, these four of them showed significantly elevated levels of ferritin and anti-MDA5 Ab titers and were considered to have high disease activity; yet, all of them survived. CONCLUSIONS: Our study indicated that anti-MDA5 Ab-positive DM patients with hyperferritinemia, a high anti-MDA5 Ab titer, and an increased urine protein/creatinine ratio should be carefully managed, bearing in mind a complication of TMA.

Age-associated CD4+ T cells with B cell-promoting functions are regulated by ZEB2 in autoimmunity.

Aging is a significant risk factor for autoimmunity, and many autoimmune diseases tend to onset during adulthood. We conducted an extensive analysis of CD4+ T cell subsets from 354 patients with autoimmune disease and healthy controls via flow cytometry and bulk RNA sequencing. As a result, we identified a distinct CXCR3midCD4+ effector memory T cell subset that expands with age, which we designated "age-associated T helper (THA) cells." THA cells exhibited both a cytotoxic phenotype and B cell helper functions, and these features were regulated by the transcription factor ZEB2. Consistent with the highly skewed T cell receptor usage of THA cells, gene expression in THA cells from patients with systemic lupus erythematosus reflected disease activity and was affected by treatment with a calcineurin inhibitor. Moreover, analysis of single-cell RNA sequencing data revealed that THA cells infiltrate damaged organs in patients with autoimmune diseases. Together, our characterization of THA cells may facilitate improved understanding of the relationship between aging and autoimmune diseases.

B cell receptor repertoire abnormalities in autoimmune disease.

B cells play a crucial role in the immune response and contribute to various autoimmune diseases. Recent studies have revealed abnormalities in the B cell receptor (BCR) repertoire of patients with autoimmune diseases, with distinct features observed among different diseases and B cell subsets. Classically, BCR repertoire was used as an identifier of distinct antigen-specific clonotypes, but the recent advancement of analyzing large-scale repertoire has enabled us to use it as a tool for characterizing cellular biology. In this review, we provide an overview of the BCR repertoire in autoimmune diseases incorporating insights from our latest research findings. In systemic lupus erythematosus (SLE), we observed a significant skew in the usage of VDJ genes, particularly in CD27+IgD+ unswitched memory B cells and plasmablasts. Notably, autoreactive clones within unswitched memory B cells were found to be increased and strongly associated with disease activity, underscoring the clinical significance of this subset. Similarly, various abnormalities in the BCR repertoire have been reported in other autoimmune diseases such as rheumatoid arthritis. Thus, BCR repertoire analysis holds potential for enhancing our understanding of the underlying mechanisms involved in autoimmune diseases. Moreover, it has the potential to predict treatment effects and identify therapeutic targets in autoimmune diseases.

OMERACT 2023 Systemic Lupus Erythematosus Special Interest Group: Winnowing and Binning Preliminary Candidate Domains for the Core Outcome Set.

BACKGROUND: The Outcome Measures in Rheumatology (OMERACT) Systemic Lupus Erythematosus (SLE) Working Group held a Special Interest Group (SIG) at the OMERACT 2023 conference in Colorado Springs where SLE collaborators reviewed domain sub-themes generated through qualitative research and literature review. OBJECTIVE: The objective of the SIG and the subsequent meetings of the SLE Working Group was to begin the winnowing and binning of candidate domain sub-themes into a preliminary list of candidate domains that will proceed to the consensus Delphi exercise for the SLE COS. METHODS: Four breakout groups at the SLE SIG in Colorado Springs winnowed and binned 132 domain sub-themes into candidate domains, which was continued with a series of virtual meetings by an advisory group of SLE patient research partners (PRPs), members of the OMERACT SLE Working Group Steering Committee, and other collaborators. RESULTS: The 132 domain sub-themes were reduced to a preliminary list of 20 candidate domains based on their clinical and research relevance for clinical trials and research studies. CONCLUSION: A meaningful and substantial winnowing and binning of candidate domains for the SLE COS was achieved resulting in a preliminary list of 20 candidate domains.