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.

Telitacicept in patients with active systemic lupus erythematosus: results of a phase 2b, randomised, double-blind, placebo-controlled trial.

OBJECTIVES: This phase 2b, randomised, double-blind, placebo-controlled trial evaluated the efficacy and safety of telitacicept, a novel fusion protein that neutralises signals of B lymphocyte stimulator and a proliferation-inducing ligand, in active systemic lupus erythematosus (SLE). METHODS: Adult patients with active SLE (n=249) were recruited from 29 hospitals in China and randomised 1:1:1:1 to receive subcutaneous telitacicept at 80 mg (n=62), 160 mg (n=63), 240 mg (n=62) or placebo (n=62) once weekly in addition to standard therapy. The primary endpoint was the proportion of patients achieving an SLE Responder Index 4 (SRI-4) response at week 48. Missing data were imputed using the last observation carried forward method. RESULTS: At week 48, the proportion of patients achieving an SRI-4 response was 75.8% in the 240 mg telitacicept group, 68.3% in the 160 mg group, 71.0% in the 80 mg group and 33.9% in the placebo group (all p<0.001). Significant treatment responses were observed in secondary endpoints, including a ≥4-point reduction on the Systemic Lupus Erythematosus Disease Activity Index, a lack of Physician's Global Assessment score worsening and a glucocorticoid dose reduction in the 240 mg group. Telitacicept was well tolerated, and the incidence of adverse events and serious adverse events was similar between the telitacicept and placebo groups. CONCLUSIONS: This phase 2b clinical trial met the primary endpoint. All telitacicept groups showed a significantly higher proportion of patients achieving an SRI-4 response than the placebo group at week 48, and all doses were well tolerated. These results support further investigations of telitacicept in clinical trials involving more diverse populations and larger sample sizes. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT02885610).

Unexpected discovery of renal mass in a patient with granulomatosis with polyangiitis: accidental or inevitable?

Granulomatosis with polyangiitis (GPA) is an uncommon disorder that mainly involves the upper and lower respiratory tract and kidney, presenting as sinusitis, saddle nose, otitis media, pulmonary nodule and cavity, rapidly progressive glomerulonephritis. It also affects skin, eye, heart, joint and nervous system. Renal involvement in GPA is commonly manifested as necrotising glomerulonephritis, while renal mass is very rare. We herein present two hospitalised cases with fever, pulmonary cavity and renal mass. Clinical course and examinations of the cases, from symptoms to diagnosis, will be discussed in detail, along with a relevant literature review of this unusual renal manifestation.

Increase in Mitochondrial Mass of Lymphocyte Subsets in Anti-MDA5 and TIF1-γ-Positive Dermatomyositis Patients.

OBJECTIVES: The mitochondrial function in anti-MDA5 and TIF1-γ-positive dermatomyositis (DM) is relatively unknown. This study attempted to explore mitochondrial mass within the peripheral lymphocyte subsets of anti-MDA5 and TIF1-γ-positive DM. METHODS: This cross-sectional study enrolled 109 DM patients and 32 healthy controls (HCs). The mitochondrial mass of peripheral lymphocyte subsets was analyzed via flow cytometry using median fluorescence intensity assessment. RESULTS: Compared with HCs, there was an abnormal change in peripheral lymphocyte subsets in anti-MDA5 and anti-TIF1-γ-positive DM patients. Anti-MDA5 and anti-TIF1-γ-positive DM patients also exhibited a significantly elevated mitochondrial mass in peripheral lymphocyte subsets. Furthermore, anti-MDA5 antibody levels were positively associated with the mitochondrial mass of most lymphocyte subsets in anti-MDA5-positive DM patients. Univariate logistic regression analysis indicated that the increased mitochondrial mass in some peripheral lymphocyte subsets was related to the occurrence of anti-MDA5-positive DM and presence of anti-MDA5 antibodies. Similar results were obtained in anti-TIF1-γ-positive DM patients. CONCLUSIONS: Abnormal lymphocyte subset counts and percentages as well as altered mitochondrial mass in anti-MDA5 and TIF1-γ-positive DM patients were associated with anti-MDA5 and TIF1-γ antibodies. We believe that these results may provide novel mitochondria-based insights into DM pathogenesis.

Rare renal proximal tubular dysfunctions in primary biliary cholangitis.

INTRODUCTION: Renal involvement of primary biliary cholangitis (PBC) usually presents as distal renal tubular acidosis. Proximal tubular (PT) dysfunctions in PBC were rarely reported with unclear clinicopathological characteristics and renal prognosis. METHODS: We identified 11 cases of PBC with PT dysfunctions (PBC-PT). Their medical document, kidney pathology, and follow-up data were retrospectively reviewed and analyzed. RESULTS: The 11 PBC-PT patients were mainly middle-aged (57.8 ± 5.2 years) females (81.8%). Most of them were asymptomatic PBC (7, 63.6%) with a high prevalence of elevated serum immunoglobulin M (IgM, 81.8%) and G (IgG, 54.5%) levels. In the kidney, they had a mean estimated glomerular filtration rate (eGFR) level of 46.54 ± 23.03 ml/min/1.73m2, and 81.8% of them had eGFR below 60 ml/min/1.73m2. They showed different degrees of PT dysfunctions, including hyperuricosuria, hypouricemia, normoglycemic glycosuria, generalized aminoaciduria, hyperphosphaturia, and hypophosphatemia. Their kidney pathology showed tubulointerstitial nephritis with lymphoplasmacytic infiltrates, brush border defects, and proximal tubulitis. After glucocorticoids treatment, the PT dysfunctions manifesting as hypophosphatemia, hypouricemia, and renal glycosuria all recovered, and the eGFR levels were improved from 43.24 ± 19.60 ml/min/1.73m2 to 55.02 ± 21.14 ml/min/1.73m2 (p = 0.028), accompanied by significant improvements of serum IgM levels (from 5.97 ± 4.55 g/L to 2.09 ± 1.48 g/L, p = 0.019). CONCLUSIONS: The PT dysfunctions were rare in PBC patients, and glucocorticoids treatment could benefit the improvements of eGFR and tubular functions.

Identification of Anti-SNRPA as a Novel Serological Biomarker for Systemic Sclerosis Diagnosis.

Systemic sclerosis (SSc) is a systemic autoimmune disorder that leads to vasculopathy and tissue fibrosis. A lack of reliable biomarkers has been a challenge for clinical diagnosis of the disease. We employed a protein array-based approach to identify and validate SSc-specific autoantibodies. Phase I involved profiled autoimmunity using human proteome microarray (HuProt arrays) with 90 serum samples: 40 patients with SSc, 30 patients diagnosed with autoimmune diseases, and 20 healthy subjects. In Phase II, we constructed a focused array with candidates identified antigens and used this to profile a much larger cohort comprised of serum samples. Finally, we used a western blot analysis to validate the serum of validated proteins with high signal values. Bioinformatics analysis allowed us to identify 113 candidate autoantigens that were significantly associated with SSc. This two-phase strategy allowed us to identify and validate anti-small nuclear ribonucleoprotein polypeptide A (SNRPA) as a novel SSc-specific serological biomarker. The observed positive rate of anti-SNRPA antibody in patients with SSc was 11.25%, which was significantly higher than that of any disease control group (3.33%) or healthy controls (1%). In conclusion, anti-SNRPA autoantibody serves as a novel biomarker for SSc diagnosis and may be promising for clinical applications.

Infectious agents and pathogenesis of Behçet's disease: An extensive review.

Behçet's disease (BD) is a multisystemic chronic vasculitis. Sustained and enhanced immune responses were reportedly associated with active BD. Although genetic polymorphisms increase development risk, genetic factors alone cannot account for BD development, suggesting the involvement of exogenous factors. Also, how various infectious agents promote BD in high-risk populations is not fully understood. In this review, we summarized the current findings on the associations of infectious agents with BD pathogenesis. The review also highlights the potential microbial risk factors and their pathogenic role in BD progression. Interactions between genetic and infectious risk factors was also discussed. Furthermore, evidence implied that after the eradication of infectious agents, BD symptoms and recurrence decreased, thus highlighting that combined use of antibiotics may be an effective therapy for BD. Finally, we summarized the main limitation of the current related studies, providing valuable insights and a basis for future studies on BD pathogenic factors.

Baricitinib for the treatment of intestinal Behçet's disease: A pilot study.

OBJECTIVES: The pilot study aims to explore the efficacy and safety of baricitinib in treating refractory intestinal Behçet's disease (BD). METHODS: We consecutively enrolled patients with refractory intestinal BD from October 2020 to September 2022. They were treated with baricitinib 2-4 mg daily, with background glucocorticoids and immunosuppressants. Efficacy assessment included the global gastrointestinal symptom scores, the endoscopy scores, the Disease activity index for intestinal Behçet's disease (DAIBD), and the inflammatory parameters. Side effects were recorded. RESULTS: The thirteen patients (six males and seven females) had a median follow-up of eleven months, 76.92% (10/13) patients achieved complete remission of global gastrointestinal symptom scores, and 66.7% (6/9) had mucosal healing on endoscopy. The DAIBD scores decreased significantly, as well as the C-reactive protein level. Baricitinib showed a glucocorticoid-sparing effect, and the safety profile is favorable. CONCLUSION: Baricitinib might be a potential choice in treating refractory intestinal BD.

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.

Cancer occurrence after SLE: effects of medication-related factors, disease-related factors and survival from an observational study.

OBJECTIVES: To explore the survival and risk factors for cancer occurrence after SLE (SLE-CA). METHODS: Patients with cancer diagnosed after SLE in Peking Union Medical College Hospital between January 2006 and September 2017 were recruited and followed. Data regarding medication-related and disease-related factors and survival were collected and compared with matched controls. Logistic regressions were applied to identify risk factors. The Kaplan-Meier method with a log-rank test was performed to evaluate survival. RESULTS: Forty-five SLE-CA patients and 128 controls were included, with the most common cancer site being the female genital system. SLE-CA patients were exposed to a higher cumulative dosage of CYC, with less mucocutaneous and haematologic involvement and higher anti-dsDNA positivity. At the time of cancer diagnosis, SLE-CA patients had lower SLEDAI 2000 (SLEDAI-2K), tended to achieve Definitions of Remission in SLE remission and minimal disease activity, but had higher SLICC/ACR Damage Index. Multivariable analysis identified high dosage of CYC [odds ratio (OR) 1.027, 95% CI 1.008, 1.046; P = 0.005] and low SLEDAI-2K at cancer diagnosis (OR 0.756, 95% CI 0.579, 0.986; P = 0.039) as risk factors. Mucocutaneous (OR 0.330, 95% CI 0.110, 0.991; P = 0.048) and haematologic involvement (OR 0.304, 95% CI 0.103, 0.902; P = 0.032) were negatively associated with cancer occurrence after SLE. The 5- and 10-year survival rates in SLE-CA patients were 95.2% and 92.1%, respectively. No significant difference of survival was observed between SLE-CA patients and controls (P = 0.177). CONCLUSION: High dosage of CYC and disease-related factors (low SLEDAI-2K, less mucocutaneous and haematologic involvement) were related factors for cancer occurrence after SLE, while no survival difference was observed.