USP28 Serves as a Key Suppressor of Mitochondrial Morphofunctional Defects and Cardiac Dysfunction in the Diabetic Heart.

BACKGROUND: The majority of people with diabetes are susceptible to cardiac dysfunction and heart failure, and conventional drug therapy cannot correct diabetic cardiomyopathy progression. Herein, we assessed the potential role and therapeutic value of USP28 (ubiquitin-specific protease 28) on the metabolic vulnerability of diabetic cardiomyopathy. METHODS: The type 2 diabetes mouse model was established using db/db leptin receptor-deficient mice and high-fat diet/streptozotocin-induced mice. Cardiac-specific knockout of USP28 in the db/db background mice was generated by crossbreeding db/m and Myh6-Cre+/USP28fl/fl mice. Recombinant adeno-associated virus serotype 9 carrying USP28 under cardiac troponin T promoter was injected into db/db mice. High glucose plus palmitic acid-incubated neonatal rat ventricular myocytes and human induced pluripotent stem cell-derived cardiomyocytes were used to imitate diabetic cardiomyopathy in vitro. The molecular mechanism was explored through RNA sequencing, immunoprecipitation and mass spectrometry analysis, protein pull-down, chromatin immunoprecipitation sequencing, and chromatin immunoprecipitation assay. RESULTS: Microarray profiling of the UPS (ubiquitin-proteasome system) on the basis of db/db mouse hearts and diabetic patients' hearts demonstrated that the diabetic ventricle presented a significant reduction in USP28 expression. Diabetic Myh6-Cre+/USP28fl/fl mice exhibited more severe progressive cardiac dysfunction, lipid accumulation, and mitochondrial disarrangement, compared with their controls. On the other hand, USP28 overexpression improved systolic and diastolic dysfunction and ameliorated cardiac hypertrophy and fibrosis in the diabetic heart. Adeno-associated virus serotype 9-USP28 diabetic mice also exhibited less lipid storage, reduced reactive oxygen species formation, and mitochondrial impairment in heart tissues than adeno-associated virus serotype 9-null diabetic mice. As a result, USP28 overexpression attenuated cardiac remodeling and dysfunction, lipid accumulation, and mitochondrial impairment in high-fat diet/streptozotocin-induced type 2 diabetes mice. These results were also confirmed in neonatal rat ventricular myocytes and human induced pluripotent stem cell-derived cardiomyocytes. RNA sequencing, immunoprecipitation and mass spectrometry analysis, chromatin immunoprecipitation assays, chromatin immunoprecipitation sequencing, and protein pull-down assay mechanistically revealed that USP28 directly interacted with PPARα (peroxisome proliferator-activated receptor α), deubiquitinating and stabilizing PPARα (Lys152) to promote Mfn2 (mitofusin 2) transcription, thereby impeding mitochondrial morphofunctional defects. However, such cardioprotective benefits of USP28 were largely abrogated in db/db mice with PPARα deletion and conditional loss-of-function of Mfn2. CONCLUSIONS: Our findings provide a USP28-modulated mitochondria homeostasis mechanism that involves the PPARα-Mfn2 axis in diabetic hearts, suggesting that USP28 activation or adeno-associated virus therapy targeting USP28 represents a potential therapeutic strategy for diabetic cardiomyopathy.

Single-cell analyses highlight the proinflammatory contribution of C1q-high monocytes to Behçet's disease.

Behçet's disease (BD) is a chronic vasculitis characterized by systemic immune aberrations. However, a comprehensive understanding of immune disturbances in BD and how they contribute to BD pathogenesis is lacking. Here, we performed single-cell and bulk RNA sequencing to profile peripheral blood mononuclear cells (PBMCs) and isolated monocytes from BD patients and healthy donors. We observed prominent expansion and transcriptional changes in monocytes in PBMCs from BD patients. Deciphering the monocyte heterogeneity revealed the accumulation of C1q-high (C1qhi) monocytes in BD. Pseudotime inference indicated that BD monocytes markedly shifted their differentiation toward inflammation-accompanied and C1qhi monocyte-ended trajectory. Further experiments showed that C1qhi monocytes enhanced phagocytosis and proinflammatory cytokine secretion, and multiplatform analyses revealed the significant clinical relevance of this subtype. Mechanistically, C1qhi monocytes were induced by activated interferon-γ (IFN-γ) signaling in BD patients and were decreased by tofacitinib treatment. Our study illustrates the BD immune landscape and the unrecognized contribution of C1qhi monocytes to BD hyperinflammation, showing their potential as therapeutic targets and clinical assessment indexes.

Targeting heat shock protein 47 alleviated doxorubicin-induced cardiotoxicity and remodeling in mice through suppression of the NLRP3 inflammasome.

AIM: Doxorubicin-induced cardiotoxicity (DIC) is an increasing problem, occurring in many cancer patients receiving anthracycline chemotherapy, ultimately leading to heart failure (HF). Unfortunately, DIC remains difficult to manage due to an ignorance regarding pathophysiological mechanisms. Our work aimed to evaluate the role of HSP47 in doxorubicin-induced HF, and to explore the molecular mechanisms. METHODS AND RESULTS: Mice were exposed to multi-intraperitoneal injection of doxorubicin (DOX, 4mg/kg/week, for 6 weeks continuously) to produce DIC. HSP47 expression was significantly upregulated in serum and in heart tissue in DOX-treated mice and in isolated cardiomyocytes. Mice with cardiac-specific HSP47 overexpression and knockdown were generated using recombinant adeno-associated virus (rAVV9) injection. Importantly, cardiac-specific HSP47 overexpression exacerbated cardiac dysfunction in DIC, while HSP47 knockdown prevented DOX-induced cardiac dysfunction, cardiac atrophy and fibrosis in vivo and in vitro. Mechanistically, we identified that HSP47 directly interacted with IRE1α in cardiomyocytes. Furthermore, we provided powerful evidence that HSP47-IRE1α complex promoted TXNIP/NLRP3 inflammasome and reinforced USP1-mediated NLRP3 ubiquitination. Moreover, NLRP3 deficiency in vivo conspicuously abolished HSP47-mediated cardiac atrophy and fibrogenesis under DOX condition. CONCLUSION: HSP47 was highly expressed in serum and cardiac tissue after doxorubicin administration. HSP47 contributed to long-term anthracycline chemotherapy-associated cardiac dysfunction in an NLRP3-dependent manner. HSP47 therefore represents a plausible target for future therapy of doxorubicin-induced HF.

Association between premature vascular smooth muscle cells senescence and vascular inflammation in Takayasu's arteritis.

OBJECTIVES: Arterial wall inflammation and remodelling are the characteristic features of Takayasu's arteritis (TAK). It has been proposed that vascular smooth muscle cells (VSMCs) are the main targeted cells of inflammatory damage and participate in arterial remodelling in TAK. Whether VSMCs are actively involved in arterial wall inflammation has not been elucidated. Studies have shown that cellular senescence in tissue is closely related to local inflammation persistence. We aimed to investigate whether VSMCs senescence contributes to vascular inflammation and the prosenescent factors in TAK. METHODS: VSMCs senescence and senescence-associated secretory phenotype were detected by histological examination, bulk RNA-Seq and single-cell RNA-seq conducted on vascular surgery samples of TAK patients. The key prosenescent factors and the downstream signalling pathway were investigated in a series of in vitro and ex vivo experiments. RESULTS: Histological findings, primary cell culture and transcriptomic analyses demonstrated that VSMCs of TAK patients had the features of premature senescence and contributed substantially to vascular inflammation by upregulating the expression of senescence-associated inflammatory cytokines. IL-6 was found to be the critical cytokine that drove VSMCs senescence and senescence-associated mitochondrial dysfunction in TAK. Mechanistically, IL-6-induced non-canonical mitochondrial localisation of phosphorylated STAT3 (Tyr705) prevented mitofusin 2 (MFN2) from proteasomal degradation, and subsequently promoted senescence-associated mitochondrial dysfunction and VSMCs senescence. Mitochondrial STAT3 or MFN2 inhibition ameliorated VSMCs senescence in ex vivo cultured arteries of TAK patients. CONCLUSIONS: VSMCs present features of cellular senescence and are actively involved in vascular inflammation in TAK. Vascular IL-6-mitochondrial STAT3-MFN2 signalling is an important driver of VSMCs senescence.

Withdrawal of immunosuppressants and low-dose steroids in patients with stable IgG4-RD (WInS IgG4-RD): an investigator-initiated, multicentre, open-label, randomised controlled trial.

OBJECTIVES: IgG4-related disease (IgG4-RD) is an immune-mediated, fibroinflammatory disease. Induction treatment with glucocorticoid (GC) is usually effective, but its tendency of relapse makes the strategy for maintenance treatment a challenge. The WInS IgG4-RD (withdraw immunosuppressants (IMs) and steroid in stable IgG4-RD) trial tested whether discontinuation of GC and IM was feasible in stable IgG4-RD. METHODS: The WInS IgG4-RD trial was a multicentre, open-label, randomised controlled trial. Patients with IgG4-RD receiving GC+IM as maintenance treatment with clinically quiescent disease for at least 12 months were randomised (1:1:1) into three groups: group 1: withdraw GC+IM; group 2: withdraw GC but maintain IM; group 3: maintain GC+IM. The primary outcome was the relapse rate of disease within 18 months. The secondary outcomes included the changes of IgG4-RD Responder Index (RI), Physician's Global Assessment (PGA), serum IgG4 and IgG, as well as adverse events. RESULTS: One hundred and forty-six patients were randomised, with 48 patients in group 1, 49 patients in group 2 and group 3, respectively. Within the 18-month follow-up period, disease relapse occurred in 25 out of 48 (52.1%) patients in group 1 vs 7 out of 49 (14.2%) in group 2 and 6 out of 49 (12.2%) in group 3 (p<0.001). The changes in RI and PGA were significantly higher in group 1 than in group 2 (p<0.001) or group 3 (p<0.001). CONCLUSIONS: The maintenance of IMs, with or without low-dose GC, was found to be superior to withdraw GC+IM in preventing relapse for long-time stable IgG4-RD. TRIAL REGISTRATION NUMBER: NCT04124861.

Profile and clinical relevance of non-criteria antiphospholipid antibodies in patients diagnosed with or highly suspected of APS.

OBJECTIVE: This study investigates the positivity and relevance of non-criteria aPLs with clinical phenotypes in patients highly suspected of or diagnosed with APS. METHODS: Outpatient cases were included from a prospectively maintained database, and patients were grouped into APS (n = 168), seronegative APS (SNAPS, n = 9), those meeting the diagnostic criteria for clinical events without laboratory results (only-event, n = 15), those that had aPL positivity without clinical manifestations (asymptomatic APA, n = 39), and healthy controls (n = 88). Criteria aPL results and APS-related clinical features were extracted. Sixteen non-criteria aPLs were tested and analysed. RESULTS: LA, aCL and anti-ß2 glycoprotein-I were positive in 84.5%, 61.3% and 74.4% of APS patients, and 61.5%, 59.0% and 74.4% of asymptomatic APA patients, respectively. In patients negative for criteria serological tests, 23 out of 24 were positive for at least one non-criteria aPL. Triple-positive patients also had significantly higher tests of some aPLs in comparison with other groups. Stroke was associated with anti-phosphatidyl-inositol (aPI) IgG and anti-phosphatidyl-glycerol (aPG) IgG. Late embryonic loss correlated with aPI IgM, and premature birth/eclampsia was associated with aPI IgG and aPG IgG. There were also positive associations between heart valve lesions and anti-phosphatidylserine-prothrombin (aPS/PT) IgM, APS nephropathy and anti-phosphatidyl-choline IgG or aPS/PT IgG, and livedo reticularis and anti-phosphatidyl-ethanolamine IgM. CONCLUSION: The prevalence of non-criteria aPLs differed from diagnostic biomarkers in patients diagnosed with or suspected of APS. Detection of aPLs provided additive value in the evaluation of APS-related clinical manifestations.

Patient-reported quality of life and working status outcomes in ambulatory patients with idiopathic inflammatory myopathy.

OBJECTIVE: To investigate the health-related quality of life (HR-QoL), work productivity and activity impairment and associated factors among patients with idiopathic inflammatory myopathy (IIM). METHODS: This was an observational, cross-sectional study. The 189 ambulatory patients with IIM were recruited from May 2019 to May 2022. HR-QoL was measured by the European Quality of Life 5-Dimension (EQ-5D) questionnaire. The Work Productivity and Activity Impairment (WPAI) questionnaire was used to evaluate work productivity and activity impairment. The IIM-related parameters were assessed by the 8-item Manual Muscle Test (MMT-8), Myositis Disease Activity Assessment visual analogue scale (MYOACT), Myositis Damage Index (MDI), Disease Activity Score (DAS) and Physician/Patient Global Assessment (PhGA/PtGA). Quantile regression and ordinal logistic regression were performed to identify the factors, considering EQ-5D or WPAI scores as dependent variables, respectively. RESULTS: Of the 189 IIM patients enrolled, 60% had DM, 13% had PM and 27% had clinical amyopathic DM. The median EQ-5D score was 1.00 (95% CI 0.73, 1.00), 28% were employed and 45% of overall work was impaired due to health problems. EQ-5D values were positively associated with MMT-8 and negatively with MYOACT, DAS, MDI-global and PhGA/PtGA. For the WPAI, activity impairment was associated with a lower MMT-8 score, older onset age and higher PhGA only in 25th-75th percentile. Increased PtGA was associated with increased activity and overall working productivity impairment in most quantiles (P<0.05). CONCLUSION: Multiple disease characteristics were associated with reduced HR-QoL or working productivity impairment in patients with IIM, especially for PtGA.

Cardiac involvement in eosinophilic granulomatosis with polyangiitis: acute eosinophilic myocarditis and chronic inflammatory cardiomyopathy.

OBJECTIVES: Currently, cardiac involvement is used to describe all eosinophilic granulomatosis with polyangiitis (EGPA) cardiac problems. However, heterogeneity exists among them. We aimed to depict the disease spectrum of EGPA cardiac involvement and identify high-risk population. METHODS: We included EGPA patients hospitalized in our center from 2012 to 2023 and in public databases. Based on the cardiac enzymes, cardiac magnetic resonance imaging, and endomyocardial biopsy results, the patients were divided into 3 groups: eosinophilic myocarditis (EGPA-EM), chronic inflammatory cardiomyopathy (EGPA-ICM) and EGPA-Control. Their clinical, laboratory, imaging results and prognoses were collected and compared. RESULTS: A total of 193 EGPA patients were included, 118 with cardiac involvement (74 EGPA-EM, 44 EGPA-ICM) and 75 control. Among EGPA-control, EGPA-ICM and EGPA-EM, eosinophil increased (6.12/8.71/10.42 × 109/l, p< 0.01), ANCA positivity decreased (41.33/31.82/14.86%, p< 0.01), and lung involvement reduced (73.33/72.73/43.24%, p= 0.02). In EGPA-EM, cardiac troponin further elevated (0.27 vs 6.00 ng/ml, p< 0.01), ejection fractions decreased (57.79 vs 33.20%, p< 0.01), while more ST-T abnormality was observed (41.89 vs 20.45%, p= 0.02). The prognosis of EGPA-EM was significantly worse, with 14.86% death rate, and 2-year event-free survival rate below 50%. Further, we proposed a LATE-EAST diagnostic score (7 items, 9 points) to discriminate EGPA-EM from EGPA-ICM using 4 points as threshold [AUC 0.85 (95%CI 0.78-0.92), sensitivity 0.78, specificity 0.86]. CONCLUSIONS: We first proposed different subtypes of cardiac involvement in EGPA. Identification and treatment of EGPA-EM needs improvement. LATE-EAST score could recognize the high-risk EGPA-EM effectively. Multi-disciplinary treatment is warranted, immunosuppressive therapy should be given timely and anti-IL-5 antibodies be tested in trials.

Efficacy and safety of telitacicept in primary Sjögren's syndrome: a randomized, double-blind, placebo-controlled, phase 2 trial.

OBJECTIVE: To evaluate the efficacy and safety of telitacicept in adult patients with primary SS (pSS) in a phase II randomized double-blind placebo-controlled trial. METHODS: Patients with pSS with positive anti-SSA antibody and ESSDAI ≥ 5 were randomly assigned, in a 1:1:1 ratio, to receive weekly subcutaneous telitacicept 240 mg, 160 mg, or placebo for 24 weeks. The primary end point was the change from baseline in the ESSDAI at week 24. Safety was monitored. RESULTS: A total of 42 patients were enrolled and randomized (n = 14 per group). Administration of telitacicept 160 mg resulted in a significant reduction in ESSDAI score from baseline to week 24 compared with placebo (P < 0.05). The placebo-adjusted least-squares mean change from baseline was -4.3 (95% CI -7.0, -1.6; P = 0.002). While, mean change of ESSDAI in telitacicept 240 mg was -2.7(-5.6-0.1) with no statistical difference when compared that in placebo group (P = 0.056). In addition, MFI-20 and serum immunoglobulins decreased significantly (P < 0.05) at week 24 in both telitacicept groups compared with placebo. No serious adverse events were observed in the telitacicept treating group. CONCLUSION: Telitacicept showed clinical benefits and good tolerance and safety in the treatment of pSS. TRIAL REGISTRATION: ClinicalTrials.gov, https://clinicaltrials.gov, NCT04078386.

Deep learning-based automatic scoring models for the disease activity of rheumatoid arthritis based on multimodal ultrasound images.

OBJECTIVES: We aimed to investigate the value of deep learning (DL) models based on multimodal ultrasonographic (US) images to quantify RA activity. METHODS: Static greyscale (SGS), dynamic greyscale (DGS), static power Doppler (SPD) and dynamic power Doppler (DPD) US images were collected and evaluated by two expert radiologists according to the EULAR-OMERACT Synovitis Scoring system. Four DL models were developed based on the ResNet-type structure, evaluated on two separate test cohorts, and finally compared with the performance of 12 radiologists with different levels of experience. RESULTS: In total, 1244 images were used for the model training, and 152 and 354 for testing (cohort 1 and 2, respectively). The best-performing models for the scores of 0/1/2/3 were the DPD, SGS, DGS and SPD models, respectively (Area Under the receiver operating characteristic Curve [AUC] = 0.87/0.95/0.74/0.95; no significant differences). All the DL models provided results comparable to the experienced radiologists on a per-image basis (intraclass correlation coefficient: 0.239-0.756, P < 0.05). The SPD model performed better than the SGS one on test cohort 1 (score of 0/2/3: AUC = 0.82/0.67/0.95 vs 0.66/0.66/0.75, respectively) and test cohort 2 (score of 0: AUC = 0.89 vs 0.81). The dynamic DL models performed better than the static ones in most of the scoring processes and were more accurate than the most of senior radiologists, especially the DPD model. CONCLUSION: DL models based on multimodal US images allow a quantitative and objective assessment of RA activity. Dynamic DL models in particular have potential value in assisting radiologists to improve the accuracy of RA US-based grading.

Changes in serum immunoglobulin G glycosylation patterns for antiphospholipid syndrome patients with lectin microarray.

Antiphospholipid syndrome is a rare autoimmune disease characterized by persistent antiphospholipid antibodies. Immunoglobulin G plays a vital role in disease progression, with its structure and function affected by glycosylation. We aimed to investigate the changes in the serum immunoglobulin G glycosylation pattern in antiphospholipid syndrome patients. We applied lectin microarray on samples from 178 antiphospholipid syndrome patients, 135 disease controls (including Takayasu arteritis, rheumatoid arthritis and cardiovascular disease) and 100 healthy controls. Lectin blots were performed for validation of significant differences. Here, we show an increased immunoglobulin G-binding level of soybean agglutinin (p = 0.047, preferring N-acetylgalactosamine) in antiphospholipid syndrome patients compared with healthy and disease controls. Additionally, the immunoglobulin G from antiphospholipid syndrome patients diagnosed with pregnancy events had lower levels of fucosylation (p = 0.001, recognized by Lotus tetragonolobus) and sialylation (p = 0.030, recognized by Sambucus nigra I) than those with simple thrombotic events. These results suggest the unique serum immunoglobulin G glycosylation profile of antiphospholipid syndrome patients, which may inform future studies to design biomarkers for more accurate diagnosis of antiphospholipid syndrome and even for the prediction of clinical symptoms in patients.

The additional role of anti-nucleosome antibodies in the prediction of renal damage in systemic lupus erythematosus based on CSTAR (XXV).

OBJECTIVES: The predominant determinant of an unfavorable prognosis among Systemic Lupus Erythematosus (SLE) patients resides in the irreversible organ damage. This prospective cohort study aimed to identify the additional value of anti-nucleosome antibodies on organ damage accumulation in SLE patients. METHODS: Based on the Chinese SLE Treatment and Research group (CSTAR) registry, demographic characteristics, autoantibodies profiles, and clinical manifestations were collected at baseline. Follow-up data were collected by reviewing clinical records. RESULTS: Of 2481 SLE patients with full follow-up data, 663 (26.7%) were anti-nucleosome antibodies positive and 1668 (68.0%) were anti-dsDNA antibodies positive. 764 (30.8%) patients developed new organ damage during a mean follow-up of 4.31 ± 2.60 years. At baseline, patients with positive anti-nucleosome antibodies have a higher rate of lupus nephritis (50.7% vs 36.2%, p < .001). According to the multivariable Cox regression analysis, both anti-nucleosome (HR = 1.30, 95% CI, 1.09-1.54, p < .001) and anti-dsDNA antibodies (HR=1.68, 95% CI, 1.38-2.05, p < .001) were associated with organ damage accumulation. Anti-nucleosome (HR = 2.51, 95% CI, 1.81-3.46, p < .001) and anti-dsDNA antibodies (HR = 1.69, 95% CI, 1.39-2.06, p < .001) were independent predictors for renal damage. Furthermore, the combination of the two antibodies can provide more accurate information about renal damage in overall SLE patients (HR = 3.19, 95% CI, 2.49-4.10, p < .001) and patients with lupus nephritis at baseline (HR = 2.86, 95% CI, 2.29-3.57, p < .001). CONCLUSION: Besides anti-dsDNA antibodies, anti-nucleosome antibodies can also provide information about organ damage accrual during follow-up. The ability of co-positivity of anti-nucleosome and anti-dsDNA antibodies in predicting renal damage may lead to additional benefits in the follow-up of these patients.

Comparison of clinical characteristics between patients with axial spondyloarthritis with and without acute anterior uveitis: a multicentre study of the Chinese Spondyloarthritis Registry.

OBJECTIVES: This study explores the clinical characteristics associated with the occurrence of acute anterior uveitis (AAU) in patients with axial spondyloarthritis (axSpA) within a large, multicentre database. METHODS: This observational, cross-sectional study of patients with axSpA used data from the Chinese Spondyloarthritis Registry between August 1, 2018, and March 31, 2020. The demographic and clinical features of patients with and without AAU were compared. Univariate and multivariate analyses were performed to determine the association between variables and uveitis. RESULTS: A total of 4304 patients were included in this study. The prevalence of AAU in patients with axSpA was 10.59%. Multivariate logistic regression analysis revealed a positive correlation between AAU and age at diagnosis (odds ratio [OR], 1.026; p<0.001), disease duration (OR, 2.117; p<0.001), current or past Achilles tendinitis (OR, 1.692; p<0.001), current or past dactylitis (OR, 1.687; p=0.002), current or past psoriasis (OR, 3.932; p<0.001), presence of human leukocyte antigen-B27 (HLA-B27) (OR, 2.787; p<0.001), and a good response to non-steroidal anti-inflammatory drugs (NSAIDs) (OR, 1.343; p=0.027). CONCLUSIONS: AAU was the most common extra-articular manifestation in the Chinese Spondyloarthritis Registry. In Chinese patients with axSpA, older age at diagnosis, longer disease duration, presence of HLA-B27, current or past Achilles tendinitis, current or past dactylitis, current or past psoriasis, and a good response to NSAIDs were positively associated with AAU.

A Glimpse into Humoral Response and Related Therapeutic Approaches of Takayasu's Arteritis.

Takayasu's arteritis (TAK) manifests as an insidiously progressive and debilitating form of granulomatous inflammation including the aorta and its major branches. The precise etiology of TAK remains elusive, with current understanding suggesting an autoimmune origin primarily driven by T cells. Notably, a growing body of evidence bears testimony to the widespread effects of B cells on disease pathogenesis and progression. Distinct alterations in peripheral B cell subsets have been described in individuals with TAK. Advancements in technology have facilitated the identification of novel autoantibodies in TAK. Moreover, emerging data suggest that dysregulated signaling cascades downstream of B cell receptor families, including interactions with innate pattern recognition receptors such as toll-like receptors, as well as co-stimulatory molecules like CD40, CD80 and CD86, may result in the selection and proliferation of autoreactive B cell clones in TAK. Additionally, ectopic lymphoid neogenesis within the aortic wall of TAK patients exhibits functional characteristics. In recent decades, therapeutic interventions targeting B cells, notably utilizing the anti-CD20 monoclonal antibody rituximab, have demonstrated efficacy in TAK. Despite the importance of the humoral immune response, a systematic understanding of how autoreactive B cells contribute to the pathogenic process is still lacking. This review provides a comprehensive overview of the biological significance of B cell-mediated autoimmunity in TAK pathogenesis, as well as insights into therapeutic strategies targeting the humoral response. Furthermore, it examines the roles of T-helper and T follicular helper cells in humoral immunity and their potential contributions to disease mechanisms. We believe that further identification of the pathogenic role of autoimmune B cells and the underlying regulation system will lead to deeper personalized management of TAK patients. We believe that further elucidation of the pathogenic role of autoimmune B cells and the underlying regulatory mechanisms holds promise for the development of personalized approaches to managing TAK patients.

mTORC1-GLUT1-mediated glucose metabolism drives hyperactivation of B cells in primary Sjogren's syndrome.

Primary Sjögren's syndrome (pSS) is a chronic systemic autoimmune disease characterized by B cell hyperactivation and hypergrammaglobulinemia. Currently, the role of metabolic pathways in the B cells of pSS patients is poorly defined. Here, we showed that upon cytosine phosphate-guanine (CpG)/sCD40L/IL-4 stimulation, B cells proportionally increased glycolysis and oxygen consumption, and compared with B cells from healthy controls (HCs), B cells from pSS patients exhibited higher glycolysis capacity and maximal oxidative respiration (OXPHOS). We also found that glucose transporter 1 (GLUT1) expression in B cells from pSS patients was significantly higher than that in B cells from HCs. Treatment with 2-deoxy-d-glucose (2-DG) inhibited the activation of B cells in pSS patients. Both 2-DG and Metformin inhibited the proliferation, formation of plasma/plasmablasts and decreased the IgG and IgM levels in the supernatants of B cells from pSS patients. Furthermore, inhibition of mTORC1 by rapamycin had an effect similar to that of 2-DG, suppressing B cell activation, proliferation and antibody production. Taken together, we demonstrated that B cells from pSS patients are more metabolically active than those from HCs and suggested that the mTORC1-GLUT1 glycolysis pathways were the major drivers of B cell hyperactivation and autoantibody production in pSS patients.

Memory CD4+T cell profile is associated with unfavorable prognosis in IgG4-related disease: Risk stratification by machine-learning.

IgG4-related disease (IgG4-RD) is a chronic immune-mediated disease with heterogeneity. In this study, we used machine-learning approaches to characterize the immune cell profiles and to identify the heterogeneity of IgG4-RD. The XGBoost model discriminated IgG4-RD from HCs with an area under the receiver operating characteristic curve of 0.963 in the testing set. There were two clusters of IgG4-RD by k-means clustering of immunological profiles. Cluster 1 featured higher proportions of memory CD4+T cell and were at higher risk of unfavorable prognosis in the follow-up, while cluster 2 featured higher proportions of naïve CD4+T cell. In the multivariate logistic regression, cluster 2 was shown to be a protective factor (OR 0.30, 95% CI 0.10-0.91, P = 0.011). Therefore, peripheral immunophenotyping might potentially stratify patients with IgG4-RD and predict those patients with a higher risk of relapse at early time.

Synovial Oxygenation at Photoacoustic Imaging to Assess Rheumatoid Arthritis Disease Activity.

Background Synovial hypoxia is a hallmark of rheumatoid arthritis (RA). Photoacoustic (PA) imaging, based on the use of laser-generated US, can detect the oxygenation status of tissue in individuals with RA. However, large studies are lacking, with few investigating the correlation between oxygenation status and disease activity. Purpose To measure synovial oxygenation status in participants with RA by using a multimodal PA US imaging system and to determine the correlation between PA imaging-measured oxygen saturation (SO2) and disease activity. Materials and Methods In this prospective observational cohort study, multimodal PA US imaging examinations were performed on small joints of consecutive participants with RA, who were treated at two outpatient rheumatology clinics from 2019 to 2021, and healthy controls. The SO2 values of the synovium were measured with dual-wavelength PA imaging and classified into three categories-hyperoxia, intermediate oxygenation status, or hypoxia-based on the signal coloration and clustering analysis of the SO2 values. The correlations of oxygenation status with power Doppler US (PDUS) scoring and clinical disease activity index were evaluated with one-way analysis of variance and the Kruskal-Wallis test with Bonferroni correction. Results A total of 118 participants with RA (median age, 55 years [IQR, 41-62 years]; 92 women) and 15 healthy control participants (median age, 37 years [IQR, 33-41 years]; 11 women) were included. The wrist synovium was categorized as hyperoxic in 36 participants with RA, of intermediate oxygenation status in 48 participants, and hypoxic in 34 participants. All control participants had hyperoxic synovial tissues. For participants with RA, hyperoxic synovium had more affluent Doppler US-depicted vasculature than those with hypoxia and intermediate oxygenation status (mean PDUS grade: hyperoxia, 2.7 ± 0.6 [SD]; intermediate, 1.3 ± 0.7; hypoxia, 1.1 ± 0.8; P < .001). Participants with intermediate status synovium had a lower clinical disease activity index than those with hypoxia (intermediate, 11.0 [IQR, 5.0-21.5] vs hypoxia, 26.0 [IQR, 18.0-39.0]; P = .001). Conclusion Photoacoustic imaging-detected hypoxia in thickened synovium correlated with less vascularization and higher disease activity in participants with rheumatoid arthritis. Clinical trial registration no. NCT04297475 © RSNA, 2022 Online supplemental material is available for this article.

Predictors and prognosis of tracheostomy in relapsing polychondritis.

OBJECTIVE: Airway obstruction can occur in patients with relapsing polychondritis (RP) with laryngeal involvement, occasionally requiring tracheostomy to avoid serious complications. Herein, we assessed the risk factors for tracheostomy and developed a risk prediction model. METHODS: Clinical characteristics of patients with RP, with and without tracheostomy, were compared using multivariate logistic regression analysis to identify risk factors. A nomogram was developed to predict the population at risk of requiring tracheostomy. RESULTS: In total, 232 patients with RP were reviewed, of whom 146 had laryngeal involvement. Among them, 21 underwent a tracheostomy. Multivariate logistic analysis identified ages ≤ 25 or ≥ 65 (p< 0.001, OR: 24.584, 95% CI: 5.310-113.815), laryngotracheal oedema (p< 0.001, OR: 26.685, 95% CI: 4.208-169.228), and pulmonary infection (p= 0.001, OR: 18.834, 95% CI: 3.172-111.936) as independent risk factors for tracheostomy. A nomogram with a C-index of 0.936 (95% CI: 0.894-0.977) was established based on the multivariate analysis. Internal bootstrap resampling (1000 repetitions) confirmed sufficient discriminatory power with a C-index of 0.926. Decision curve analysis indicated a superior net benefit of the nomogram. Tracheostomy was associated with a significant increase in the in-hospital mortality rate (p= 0.021), but it did not affect the long-term survival rate (p= 0.706). CONCLUSION: Tracheostomy is associated with an increase in the short-term mortality rate but does not affect the long-term survival rate. The nomogram developed in this study may help identify patients at high risk for tracheostomy and aid in clinical decision-making.

Effect of smoking on thrombotic antiphospholipid syndrome: a 10-year prospective cohort study.

OBJECTIVES: Cigarette smoking is an established risk factor for autoimmune diseases. However, whether smoking plays a clear role in thrombotic antiphospholipid syndrome (TAPS) has not been determined. We aimed to investigate the effects of smoking on clinical characteristics and prognosis of TAPS. METHODS: This was a prospective cohort study from 2013 to 2022. During the study period, 297 patients were diagnosed with TAPS, including 82 smokers and 215 non-smokers. After propensity score matching, 57 smokers and 57 non-smokers matched by age and sex were analysed. RESULTS: Overall, smokers with TAPS had more cardiovascular risk factors (CVRFs) than non-smokers, including hypertension (36.59% vs. 14.42%, P<0.001), obesity (15.85% vs. 7.44%, P=0.029), dyslipidaemia (64.63% vs. 48.37%, P=0.012), and hyperhomocysteinaemia (62.20% vs. 36.28%, P<0.001). Arterial thrombotic events were more common in smokers at diagnosis (62.20% vs. 46.05%, P=0.013), especially myocardial infarction, visceral thrombosis, and peripheral vascular thrombosis. After matching, smokers showed balanced CVRFs with non-smokers at baseline, but retained a higher prevalence of arterial thrombosis (59.65% vs. 33.33%, P=0.005), mainly distributed in cerebral vascular, cardiovascular, and retinal vascular territories. During follow-up, smokers presented a tendency for more recurrent arterial thrombosis and less recurrent venous thrombosis. Smokers had significantly poorer outcomes for organ damage with higher DIAPS (median, 2.00 vs. 1.00, P=0.008), especially in the cardiovascular (26.32% vs. 3.51%, P=0.001), gastrointestinal (15.79% vs. 1.75%, P=0.016), and ophthalmologic (10.53% vs. 00.00%, P=0.027) systems. CONCLUSION: Smoking is related to increased arterial events and poor prognosis in TAPS patients. Patients with TAPS should be fully encouraged to avoid smoking.

Changes of serum IgG glycosylation patterns in rheumatoid arthritis.

BACKGROUND: RA is a common chronic and systemic autoimmune disease, and the diagnosis is based significantly on autoantibody detection. This study aims to investigate the glycosylation profile of serum IgG in RA patients using high-throughput lectin microarray technology. METHOD: Lectin microarray containing 56 lectins was applied to detect and analyze the expression profile of serum IgG glycosylation in 214 RA patients, 150 disease controls (DC), and 100 healthy controls (HC). Significant differential glycan profiles between the groups of RA and DC/HC as well as RA subgroups were explored and verified by lectin blot technique. The prediction models were created to evaluate the feasibility of those candidate biomarkers. RESULTS: As a comprehensive analysis of lectin microarray and lectin blot, results showed that compare with HC or DC groups, serum IgG from RA patients had a higher affinity to the SBA lectin (recognizing glycan GalNAc). For RA subgroups, RA-seropositive group had higher affinities to the lectins of MNA-M (recognizing glycan mannose) and AAL (recognizing glycan fucose), and RA-ILD group had higher affinities to the lectins of ConA (recognizing glycan mannose) and MNA-M while a lower affinity to the PHA-E (recognizing glycan Galß4GlcNAc) lectin. The predicted models indicated corresponding feasibility of those biomarkers. CONCLUSION: Lectin microarray is an effective and reliable technique for analyzing multiple lectin-glycan interactions. RA, RA-seropositive, and RA-ILD patients exhibit distinct glycan profiles, respectively. Altered levels of glycosylation may be related to the pathogenesis of the disease, which could provide a direction for new biomarkers identification.