Mitoxantrone ameliorates ineffective erythropoiesis in a ß-thalassemia intermedia mouse model.

ß-thalassemia is a condition characterized by reduced or absent synthesis of ß-globin resulting from genetic mutations, leading to expanded and ineffective erythropoiesis. Mitoxantrone has been widely used clinically as an antitumor agent in light of its ability to inhibit cell proliferation. However, its therapeutic effect on expanded and ineffective erythropoiesis in ß-thalassemia is untested. We found that mitoxantrone decreased α-globin precipitates and ameliorated anemia, splenomegaly and ineffective erythropoiesis in the HbbTh3/+ mouse model of ß-thalassemia intermedia. The partially reversed ineffective erythropoiesis is a consequence of effects on autophagy as mitochondrial retention and protein levels of mTOR, P62 and LC3 in reticulocytes decreased in mitoxantrone-treated HbbTh3/+ mice. These data provide significant pre-clinical evidence for targeting autophagy as a novel therapeutic approach for ß-thalassemia.

SERPINA3, FGA, AGP1, ITIH3 and SAA1 as novel biomarkers for eosinophilic granulomatosis with polyangiitis diagnosis and activity assessment.

OBJECTIVE: To identify novel biomarkers for diagnosis and prediction of active eosinophilic granulomatosis with polyangiitis (EGPA) through data-independent acquisition (DIA) analysis. METHODS: Plasma from 11 EGPA patients and 10 healthy controls (HCs) were analyzed through DIA to identify potential biomarkers. The results were validated in 32 EGPA patients, 24 disease controls (DCs), and 20 HCs using enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve was used to assess the diagnostic value of candidate biomarkers. RESULTS: Thirty-five differentially expressed proteins (DEPs) (24 upregulated and 11 downregulated) were screened between EGPA and HC groups. Five proteins, including serine proteinase inhibitor A3 (SERPINA3), alpha-fibrinogen (FGA), alpha-1 acid glycoprotein 1(AGP1), inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3), and serum amyloid A1 (SAA1), were significantly upregulated in EGPA compared with HCs. Apart from SAA1, all proteins were also higher in EGPA patients compared with DCs. Furthermore, a panel of SERPINA3 and SAA1 exhibited potential diagnostic value for EGPA with an area under the curve (AUC) of 0.953, while a panel of SERPINA3, FGA, AGP1, and ITIH3 showed good discriminative power to differentiate EGPA from DCs with AUC of 0.926. Moreover, SERPINA3, FGA, and AGP levels were significantly higher in active EGPA and correlated well with disease activity. A combination of SERPINA3 and AGP1 exhibited an excellent AUC of 0.918 for disease activity assessment. CONCLUSION: SERPINA3, FGA, AGP1, ITIH3 and SAA1 were identified as potential biomarkers for EGPA diagnosis and disease activity assessment. Among them, as a single biomarker, SERPINA3 has the best diagnostic performance.

A microRNA sponge, LINC02193, promotes neutrophil activation by upregulating ICAM1 and is correlated with ANCA-associated vasculitis.

OBJECTIVE: To investigate the pathogenic role and underlying mechanisms of lncRNAs in antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). METHODS：: RNA-sequencing (RNA-seq) was applied to screen the expression profile of lncRNAs in peripheral leukocytes from 5 AAV patients and 5 healthy controls (HC). Candidate lncRNAs were preliminarily verified in peripheral leukocytes from 46 AAV patients and 35 HC by qRT-PCR. Then, the identified LINC02193 was further validated in peripheral neutrophils from 67 AAV patients, 45 HC and 64 disease controls. Correlation between LINC02193 levels and disease activity was analyzed. Then, a loss-of-function study was conducted to investigate the role of LINC02193 in neutrophils activation. Furthermore, bioinformatics analysis, dual luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to explore the mechanism of LINC02193 regulating neutrophils activation. RESULTS: A total of 467 upregulated and 412 downregulated lncRNAs were identified in AAV patients. From top 5 upregulated lncRNAs, an elevation of LINC02193 was validated in a larger sample of AAV patients, and positively correlated with disease activity. Knockdown of LINC02193 inhibited ROS and NO production, NETs release and adhesion to endothelial cells of differentiated human promyelocytic leukaemia HL­60 cells (dHL-60), whereas overexpression of ICAM1 counteracted these effects. Mechanistic analysis demonstrated that LINC02193 acted as a miR-485-5p sponge to relieve the repressive effect of miR-485-5p on ICAM1, thus promoting ICAM1 expression. CONCLUSION: LINC02193, a novel lncRNA identified in AAV could function as competing endogenous RNAs (ceRNA) for miR-485-5p to promote ICAM1 expression and neutrophils activation, suggesting its potential as a therapeutic target of AAV.

The role of plateletcrit in Takayasu arteritis: A potential biomarker for disease activity and 6-month treatment response.

OBJECTIVES: To determine the role of plateletcrit as a potential biomarker for disease activity and treatment response in Takayasu arteritis (TAK). METHODS: Totally, 215 newly diagnosed TAK patients were consecutively enrolled. Demographic data, clinical manifestations, laboratory and imaging examinations, and treatment strategy were recorded at baseline and at each visit during the 6-month treatment period. Normal plateletcrit (0.1%-0.4%) and hyper-plateletcrit (>0.4%) observed at baseline were used as group criteria. RESULTS: At baseline, the overall plateletcrit was 0.32 (0.24-0.38)%, with a normal and high level observed in 172 (80.00%) and 43 (20.00%) patients, respectively. Baseline plateletcrit was significantly higher in patients with active disease and associated with inflammatory biomarkers, including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and interleukin (IL)-6 (all p < .01). At 6 months, complete remission was achieved in 171 (79.53%) patients, and a significant decrease in plateletcrit was observed in these cases (p < .01). Patients with a normal baseline plateletcrit were more likely to achieve complete remission compared to those with a high baseline plateletcrit (HR = 4.65, 95% CI: 2.38-19.08, p < .01). In addition, ESR (p = .01) and IL-6 (p = .02) levels were still higher in patients with a high baseline plateletcrit at 6 months. Progression of vascular lesions was indicated in 18 (8.37%) patients at 6 months, and these patients also had significantly higher baseline plateletcrit (p = .03). CONCLUSION: Plateletcrit levels were positively related to disease activity and inflammatory index in TAK. Importantly, patients with high baseline plateletcrit levels may show a worse treatment response at 6 months.

Ferric Single-Site Catalyst Confined in a Zeolite Framework for Propane Dehydrogenation.

Non-oxidative dehydrogenation of propane is a highly efficient approach for industrial preparation of propene that is commonly catalyzed by noble Pt or toxic Cr catalysts and suffers from coking. In this work, ferric catalyst confined in a zeolite framework was synthesized by a hydrothermal procedure. The isolated Fe in the framework formed distorted tetrahedra, which were beneficial for the selective dehydrogenation of propane and reached over 95 % propene selectivity and over 99 % total olefins selectivity. This catalyst had a silanol-free structure and was oxygen tolerant, hydrothermally stable, and coke free, with a deactivation constant of 0.01 h-1 . This study provided guidance for the synthesis of structural heteroatomic zeolite and efficient propane non-oxidative dehydrogenation over early transition metals.

Exploration of molecular signatures associated with different clinical features of Takayasu arteritis based on a prospective cohort study.

Takayasu arteritis (TAK) is complicated disorder without reliable biomarkers. Here, we aimed to explore TAK-associated factor panels and their changes after biologic treatment. Five factor panels were identified: 1. systemic inflammation: C3, ESR, CRP, PLT, IL-6, C4, and IgG; 2. vascular inflammation: YKL40, IL-16, PTX3, and CCL2; 3. immune regulation panel: IL-10, IFN-γ, CCL5, and MMP1; 4. angiogenesis and fibrosis: FGF, PDGFAB, and VEGF; and 5. vascular remodeling: CD19+ B cell ratio, MMP3, and leptin. Panel 1 parameters were closely related to disease activity, while Panel 5 parameters, particularly CD19+ B cell ratio and leptin, were significantly higher in ischemic patients. After treatment, tocilizumab had a stronger inhibitory effect on Panel 1 parameters, PTX3, and YKL-40, while adalimumab led to an increase in IL-16, CCL2, and leptin levels. Altogether, these data expanded our knowledge regarding molecular background in TAK development and shed light on precise treatment in future studies.

Single-Cell RNA-Sequencing Reveals Peripheral T Helper Cells Promoting the Development of IgG4-Related Disease by Enhancing B Cell Activation and Differentiation.

Abnormal B cell differentiation plays a critical role in IgG4-related disease (IgG4-RD), but the underlying mechanism remains largely unknown. We investigated the cell landscape from three IgG4-RD retroperitoneal tissues and three control tissues using single-cell RNA-sequencing. Critical cell type or markers were further validated in the peripheral blood from the patients with IgG4-RD and healthy controls via flow cytometry as well as in the IgG4-RD and control tissue via immunofluorescence staining. The increases in B cells, plasma cells, and CD4+ T cells were found in IgG4-RD retroperitoneal tissue. Importantly, among CD4+ T cells, an increase in CD4+CXCR5-PD1hi peripheral T helper (Tph) cells with a high expression of IL-21 and TIGIT was discovered in IgG4-RD tissue, which was further validated in peripheral blood of the patients with IgG4-RD. The Tph cell and TIGIT+ Tph cell proportion were remarkably higher in active IgG4-RD patients and correlated with disease activity. Moreover, TIGIT+CD4+ cells were able to promote B cell differentiation via IL-21. Our study revealed that Tph cells are increased in IgG4-RD and probably play critical roles in B cell differentiation through TIGIT-IL-21 axis. Peripheral Tph cell and TIGIT+Tph cell are potential markers for IgG4-RD disease activity.

Treatment efficacy and safety of adalimumab versus tocilizumab in patients with active and severe Takayasu arteritis: an open-label study.

OBJECTIVE: This study aimed to compare the efficacy and safety of adalimumab (ADA) versus tocilizumab (TCZ) in patients with Takayasu arteritis (TAK). METHODS: This was a randomized, controlled, open-label study. Forty patients with active and severe TAK were enrolled. They were treated with ADA (n = 21) combined with glucocorticoids (GCs) and methotrexate (MTX) or TCZ (n = 19) combined with GCs and MTX. The planned follow-up duration was 12 months. The primary end point was the efficacy rate (ER) at 6 months. The secondary endpoints included ER at 9 and 12 months, relapse rate, GC tapering, adverse effects, and life quality changes during treatment. RESULTS: In the intention-to-treat (ITT) population, the ER at 6 months was higher in the ADA group (85.71% vs 52.63%, P= 0.02). A similar direction of effect was noted in the per-protocol set (89.47% vs 62.50%, P= 0.06). The percentages of patients who achieved a GC dose of ≤ 10 mg/day at 6 months were similar between the ADA and TCZ groups (47.37% vs 43.75%, P= 0.83). The ERs at 9 and 12 months were similar between the two groups (P> 0.05). During the first 12 months of treatment, the relapse rate and adverse event incidence were comparable between the two groups (ADA vs TCZ: 9.52% vs 10.53%, P= 0.96; 38.10% vs 47.37%, P= 0.55, respectively). CONCLUSION: ADA combined with GCs and MTX may be more efficacious than TCZ combined with GCs and MTX among patients with active and severe TAK. TRIAL REGISTRATION: Clinicaltrials.gov; NCT04300686.

Rational design of a self-assembly promoting fusion domain enhances high molecular weight levan synthesis by levansucrase SacB.

The catalytic product of levansucrase from Bacillus subtilis (SacB) is mainly composed of 10 % high molecular weight levan (HMW, ~2000 kDa) and 90 % low molecular weight levan (LMW, ~7000 Da). In order to achieve efficient production of food hydrocolloid, high molecular weight levan (HMW), with the help of molecular dynamics simulation software, a protein self-assembly element, Dex-GBD, was found and fused with the C-terminus of SacB to construct a novel fusion enzyme, SacB-GBD. The product distribution of SacB-GBD was reversed compared with SacB, and the proportion of HMW in the total polysaccharide was significantly increased to >95 %. We then confirmed that the self-assembly was responsible for the reversal of the SacB-GBD product distribution by the simultaneous modulation of SacB-GBD particle size and product distribution by SDS. The hydrophobic effect may be the main driver of self-assembly as analyzed by molecular simulations and hydrophobicity determination. Our study provides an enzyme source for the industrial production of HMW and provides a new theoretical basis for guiding the molecular modification of levansucrase towards the size of the catalytic product.

LncRNA ITGB2-AS1 promotes cisplatin resistance of non-small cell lung cancer by inhibiting ferroptosis via activating the FOSL2/NAMPT axis.

Cisplatin resistance is a major therapeutic challenge in non-small cell lung cancer (NSCLC). Herein, the regulatory role of long non-coding RNA (lncRNA) ITGB2-AS1 in regulating NSCLC cisplatin resistance was investigated. NSCLC cisplatin resistance cells were constructed using A549 and H1975 cells. Cell viability and proliferation were detected by MTT assay and colony formation assay, respectively. Cell apoptosis and cell cycle were examined by flow cytometry. GSH, MDA, ROS, and Fe2+ levels were measured by the corresponding kits. The expressions of ferroptosis-negative regulation genes (GPX4 and SLC7A11) were determined by qRT-PCR and western blot. Molecular interactions were analyzed by RNA pull-down, RIP, ChIP, and dual-luciferase reporter assays. The effects of ITGB2-AS1 silencing on NSCLC cisplatin resistance in vivo were elevated by the tumor xenograft experiment. ITGB2-AS1 expression was increased in NSCLC patients and cisplatin-resistant NSCLC cells, which was positively correlated with ferroptosis-negative regulation genes. ITGB2-AS1 knockdown suppressed resistant cell proliferation and promoted cell apoptosis and ferroptosis. ITGB2-AS1 increased NAMPT expression by binding to FOSL2, thereby repressing p53 expression. The ITGB2-AS1 knockdown also inhibited NSCLC cisplatin resistance in vivo. ITGB2-AS1 promoted NSCLC cisplatin resistance by inhibiting p53-mediated ferroptosis via activating the FOSL2/NAMPT axis.

Heme oxygenase 1 in erythropoiesis: an important regulator beyond catalyzing heme catabolism.

Heme oxygenase 1 (HO-1), encoded by the HMOX-1 gene, is the main heme oxygenase that catalyzes the degradation of heme into iron, carbon monoxide, and biliverdin. HMOX-1 gene expression is stimulated by oxidative stress and regulated at transcriptional and post-transcriptional levels. After translation, subcellular location and protein stability of HO-1 are also altered by different extracellular and intracellular stimuli. HO-1 plays a key role in regulating iron homeostasis and cell protection and has become a new target for disease treatment. Erythropoiesis is a tightly controlled, iron-dependent process that begins with hematopoietic stem cells and maturates to red blood cells. HO-1 is expressed in hematopoietic stem/progenitor cells, hematopoietic niche cells, erythroblasts, and especially erythroblastic island and phagocytic macrophages. HO-1 functions importantly in the entire erythroid development process by influencing hematopoietic stem cell proliferation, erythroid lineage engagement, terminal erythroid differentiation, and even senescent RBC erythrophagocytosis. HO-1 is also related to stress erythropoiesis and certain red blood cell diseases. Elucidation of HO-1 regulation and function in erythropoiesis will be of great significance for the treatment of related diseases.

Single-cell profiling of ineffective erythropoiesis in a mouse model of ß-thalassaemia intermedia.

Beta-thalassaemia is an inherited haemoglobin disorder characterised by ineffective erythropoiesis (IE). The detailed pathogenesis of IE remains unclear. In this study, we used single-cell RNA sequencing (scRNA-seq) to examine IE in Th3/+ ß-thalassaemic mice. The results showed that the erythroid group was remarkably expanded, and genes involved in biological processes such as iron metabolism, haeme synthesis, protein folding, and response to heat were significantly upregulated from erythroid progenitors to reticulocytes in ß-thalassaemic mice. In particular, we identified a unique cell population close to reticulocytes, named ThReticulocytes, characterised by a high level of heat shock protein 70 (Hsp70) expression and dysregulation of iron metabolism and haeme synthesis signalling. Treatment of ß-thalassaemic mice with the haeme oxygenase inhibitor tin-mesoporphyrin effectively improved the iron disorder and IE, and the ThReticulocyte population and Hsp70 expression were significantly suppressed. This study revealed in detail the progression of IE at the single-cell level and possibly provided clues to find therapeutic targets in thalassaemia.

Comparison of the efficacy and safety of leflunomide versus placebo combined with basic prednisone therapy in patients with active disease phase of Takayasu arteritis: study protocol for a randomized, double-blinded controlled trial (Takayasu arteritis clinical trial in China: TACTIC).

Background: Takayasu arteritis (TAK) is an immune-induced granulomatous vasculitis that occurs primarily in young Asian women. Our previous cohort studies have indicated that leflunomide (LEF), which can lead to rapid induction and might be a promising alternative treatment for TAK. Objectives: To compare the efficacy and safety of LEF versus placebo combined with prednisone for active TAK in a Chinese population. Design: This will be a multicenter, randomized, double-blinded controlled trial aiming to recruit 116 TAK patients with active disease. This study will last 52 weeks. Methods and analysis: Participants will be assigned randomly to the LEF intervention arm or placebo control arm at a 1:1 ratio. Initially, LEF combined with prednisone will be given to the intervention arm and a placebo tablet combined with prednisone will be given to the placebo arm. At the end of week 24, subjects who achieved clinical remission or partial clinical remission will proceed to maintenance therapy with LEF to the end of week 52; those who did not achieve clinical remission or partial clinical remission in the LEF intervention arm will drop out from the study, and those in the placebo control arm will switch to LEF treatment to week 52. The primary endpoint will be the clinical remission rate of LEF versus placebo at the end of week 24. The secondary endpoints will be the time to clinical remission, mean dose of prednisone, disease recurrence, time to recurrence, adverse events, as well as clinical remission in subjects who switched from the placebo control arm to LEF therapy after week 24. Intention to treat will be the primary analysis. Discussion: This is the first randomized double-blinded placebo-controlled trial to clarify the efficacy and safety of LEF in treating active TAK. The results will provide more evidence for TAK management. Registration: ClinicalTrials.gov identifier: NCT02981979.

PET vascular activity score for predicting new angiographic lesions in patients with Takayasu arteritis: a Chinese cohort study.

OBJECTIVE: To investigate the ability of 18F-fluorodeoxyglucose PET/CT to predict new lesions in Takayasu arteritis. METHODS: Eighty-two Chinese patients with newly diagnosed Takayasu arteritis were recruited. Their clinical characteristics, serum biomarkers and imaging results were recorded at baseline and every visit. They were followed up for at least 2 years. New angiographic lesions were evaluated by magnetic resonance angiography. Baseline PET vascular activity scores (PETVAS) for predicting new lesions were evaluated. RESULTS: At baseline, a moderate correlation was observed between PETVAS and ESR (r = 0.74, P < 0.01) and CRP level (r = 0.69, P < 0.01). Overall, 18 (22%) patients showed new lesions on imaging during a median follow-up time of 36 months. The median time to the first occurrence of new lesions was 18 months. Compared with patients without new lesions, the patients with new lesions included more female patients (67.2% vs 94.4%, P = 0.03), patients with higher ESR values (20 vs 49, P = 0.02) and patients with active disease (62.5% vs 94.4%, P < 0.01). Multivariate Cox regression analysis revealed PETVAS was an independent risk factor for new angiographic lesions (PETVAS ≥8, hazard ratio = 7.56; 95% CI 2.20, 26.01, P < 0.01) with adjustment of age, sex, chest pain, ESR and Physician Global Assessment. Furthermore, patients with PETVAS ≥8 at baseline were more likely to experience adverse events including arterial ischaemic events during the follow-up. CONCLUSION: PETVAS showed good performance in predicting new lesions in Takayasu arteritis.

Associations of microcirculation damage on nailfold capillaroscopy with supra-aortic severe ischemic events in patients with Takayasu arteritis.

OBJECTIVE: To evaluate the clinical characteristics and nailfold microcirculation and explore the associations with severe ischemic events (SIEs) in Takayasu arteritis (TA) with supra-aortic involvement. METHODS: Eighty-one patients with supra-aortic artery involvement who underwent nailfold video-capillaroscopy (NVC) of their hands were enrolled from the East China TA (ECTA) cohort between August and December 2021. Clinical features and capillaroscopy variables associated with supra-aortic SIEs were analyzed by multivariate logistic regression. RESULTS: Overall, 71 patients were female, and 42 experienced supra-aortic SIEs, among whom there was a higher prevalence of hypertension and the number of supra-aortic artery stenosis (P = 0.005, and 0.003, respectively). Furthermore, intergroup differences in capillary density (P < 0.001) and minor morphology abnormalities (P < 0.001) were significant. After adjustment for all confounders, multivariate logistic regression revealed hypertension (odds ratio [OR]: 7.3, 95% confidence interval [CI]: 1.6-33.7, P = 0.011), the number of supra-aortic arteries stenosis (≥4, OR: 6.8, 95% CI: 1.4-34.6, P = 0.020), capillary density (≤7.2/mm, OR: 43.0, 95% CI: 7.0-264.6, P < 0.001) and minor abnormalities (OR: 34.2, 95% CI: 3.6-325.1; P = 0.002) were independent risk factors for supra-aortic SIEs. capillary density (≤7.2/mm) and minor abnormalities or combined with at least two of the three items in the matrix model showed the probability of supra-aortic SIEs was 61.2-87.6%. CONCLUSION: Decreased capillary density and morphologic abnormalities indicated that hypoperfusion was more likely to be observed in supra-aortic SIEs patients. Combined NVC indicators could be instrumental for early identification of supra-aortic SIEs. Key Points • Minor morphological abnormalities and hemorrhages were only observed in supra-aortic SIEs patients. • Capillaroscopic density and minor morphological abnormalities or combined with at least two of the three items in the matrix model showed the probability occurrence of supra-aortic SIEs was 61.2-87.6%.

Circular RNA expression profiles and identification of hsa_circ_0028381 as a potential biomarker of anti-neutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVES: Accumulating evidence indicates the role of dysregulated circRNAs in autoimmune diseases. In this study, we investigated their role in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) by analysing the expression profiles of circRNA in plasma of AAV patients and exploring their potential as biomarkers of AAV. METHODS: RNA-sequencing (RNA-seq) was performed to identify the plasma circRNA and mRNA expression profiles from five AAV patients and five healthy controls (HCs). Quantitative reverse-transcription (qRT)-PCR confirmed that hsa_circ_0028381 was confirmed to be significantly upregulated in a validation cohort of 51 AAV patients and 30 HCs and was further verified in other connective tissue diseases (CTDs). The diagnostic value of hsa_circ_0028381 was assessed by receiver operating characteristic (ROC) curve analysis. RESULTS: RNA expression profiles revealed aberrant expression of 143 circRNAs (62 upregulated and 81 downregulated) and 304 mRNAs (151 upregulated and 153 downregulated) in AAV patients compared to HCs. qRT-PCR verification suggested that hsa_circ_0028381 levels were significantly increased in plasma from AAV patients compared to those in HCs and other CTDs. ROC curve analysis showed has_circ_0028381 had good diagnostic value for distinguishing AAV patients from controls (HCs and other CTDs) with an area under the curve (AUC) of 0.81. In addition, hsa_circ_0028381 was associated with renal involvement. Most importantly, increased baseline levels of hsa_circ_0028381 had predictive value for progression to end-stage renal disease (ESRD). CONCLUSIONS: RNA-seq revealed that circRNAs are aberrantly expressed in the plasma of AAV patients. Hsa_circ_0028381 was implicated as a potential biomarker for AAV diagnosis and renal prognosis.

A novel molecular mechanism of vascular fibrosis in Takayasu arteritis: macrophage-derived GPNMB promoting adventitial fibroblast extracellular matrix production in the aorta.

Takayasu arteritis (TAK) is a chronic large vessel disease characterized by aortic fibrotic thickening, which was mainly mediated by activation of aorta adventitial fibroblasts (AAFs). Our previous genetic study demonstrated that TAK-associated locus IL6 rs2069837 regulated glycoprotein non-metastatic melanoma protein B (GPNMB) expression. Thus, this study aimed to investigate the pathogenic role of GPNMB in TAK. Through pathological staining, we find that GPNMB was mainly expressed in vascular adventitia and positively correlated with adventitial extracellular matrix (ECM) expression in TAK vascular lesion. Specifically, GPNMB was increased in adventitial CD68+ macrophages, which were closely located with CD90+ adventitial fibroblasts. In in-vitro cell culture, THP-1-derived macrophages with GPNMB overexpression promoted ECM expression in AAFs. This effect was also confirmed in aortic tissue or AAFs culture with GPNMB overexpression or active GPNMB protein stimulation. Mechanistically, Co-IP assay and siRNA or inhibitor intervention demonstrated that integrin αVß1 receptor mediated GPNMB effect on AAFs, which also activated downstream Akt and Erk pathway in AAFs. Furthermore, we showed that leflunomide treatment inhibited GPNMB-mediated fibrosis in AAFs, as well as GPNMB expression in macrophages, which were also partially validated in leflunomide-treated patients. Taken together, these data indicated that macrophage-derived GPNMB promotes AAFs ECM expression via the integrin αVß1 receptor and Akt/Erk signaling pathway and leflunomide might play an anti-fibrotic role in TAK by interfering with the macrophage-derived GPNMB/AAFs axis. This study provides evidence that targeting GPNMB is a potential therapeutic strategy for treating vascular fibrosis in TAK.

COVID-19 infection characteristics, risk factors and its potential impacts on Takayasu arteritis: a web-based survey in a large cohort.

Objectives: To investigate the characteristics of COVID-19 and its impact on patients with Takayasu's arteritis (TAK). Methods: A web-based survey was administered to a TAK cohort and their co-residents in China during January 2023. Infection symptoms, post-acute sequelae of COVID-19 (PASC), potential impacts of COVID-19 on patients' disease condition, treatment and immune-related parameters were analyzed. In addition, risk factors for COVID-19 and disease relapse after infection were explored. Results: The infection rate was significantly lower in patients with TAK than in co-residents (79.13% vs 90.67%, p=0.025). TAK patients were more prone to gastrointestinal symptoms (17.78% vs 5.88%, p=0.024), sleep problems (25.15% vs 10.29%, p=0.011), and symptoms involving more than 2 organs (58.90% vs 35.29%, p=0.001) after infection. Although only 2.45% of TAK patients were hospitalized and none progressed to life-threatening conditions, they were more likely to suffer from PASC (26.38% vs 13.24%, p=0.029), especially active patients. Active disease after the pandemic was significantly lower in infected patients than uninfected patients (21/163, 12.88% vs. 11/43, 25.58%, p=0.041). The presence of multiple system symptoms was a risk factor for active TAK after infection [OR: 3.62 (95% CI 1.06-12.31), p=0.040]. Moreover, csDMARDs treatment was a risk factor for COVID-19 infection [OR: 3.68 (95% CI 1.56-8.66), p=0.002]. Conclusion: Although TAK patients with COVID-19 have more acute and post-acute symptoms, there is no adverse outcome and the risk of disease relapse does not increase. Patients treated with csDMARDs may be at higher risk of infection and deserve more clinical attention.

Risk factors of aortic regurgitation progression in Chinese patients with Takayasu's arteritis: a prospective cohort study.

Objective: To elucidate the 3-year follow-up outcomes and risk factors associated with aortic regurgitation progression in Takayasu's arteritis (TAK). Methods: This study was a prospective cohort study conducted among 77 patients with TAK at Zhongshan Hospital, Fudan University, China. All the participants were followed up and assessed with echocardiography for 3 years, and the baseline characteristics and dynamic changes in the aortic valve were recorded and investigated. A multivariable Cox model was used to explore the risk factors for aortic regurgitation progression. Results: The median onset age was 36.9 (26.0-44.4) years, and 57 patients (74.0%) were females. Fifty patients (64.9%) complained of aortic regurgitation, which was the most common valvular lesion at baseline. During the 3-year follow-up period, the progression of aortic regurgitation was observed in 29 (37.7%) patients with TAK. The progression group had higher baseline erythrocyte sedimentation rate (ESR; p = 0.013) and interleukin (IL)-6 (p = 0.029) levels and lower early treatment remission rates (p = 0.024). According to the Cox model, the elevated baseline IL-6 level [>13 pg/ml, hazard ratio (HR) = 2.4, 95% confidence interval (CI) = 1.0-5.8, p = 0.042] and absence of early treatment remission (HR = 3.3, 95% CI = 1.3-8.2, p = 0.010) were the independent risk factors for aortic regurgitation deterioration. Conclusion: About one-third of patients with TAK experienced aortic regurgitation progression within 3 years from first admission. Elevated IL-6 levels at baseline and absence of early treatment remission were the two important risk factors for subsequent aortic regurgitation progression.

Biomarker Changes and Molecular Signatures Associated with Takayasu Arteritis Following Treatment with Glucocorticoids and Tofacitinib.

Objective: This study aimed to analyze biomarker changes in patients with TAK following treatment with glucocorticoids (GCs) and tofacitinib (TOF). Methods: Seventeen patients from a prospective TAK cohort treated with GCs and TOF and 12 healthy individuals were recruited. TAK associated cytokines, chemokines, growth factors, and MMPs were analyzed in these patients before and after GCs and TOF treatment, and healthy controls. Molecular signatures associated with clinical features were evaluated. Results: Patients' cytokines (PTX3, IL-6, IFN-γ), chemokines (IL-16, CCL22, CCL2), growth factors (VEGF), and MMP9 levels were significantly higher at baseline (all p < 0.05), while patients' FGF-2 levels were significantly lower (p = 0.02). After treatment, IL-10 was significantly increased at 6 months (p=0.007), and inflammatory cytokines such as PTX3, IL-6 demonstrated a downward trend. Patients without vascular occlusion had higher baseline CCL22 levels than patients with it (p = 0.05), which remained persistently higher after treatment. Radar plot analysis demonstrated that PTX3 was closely correlated with disease activity. In addition, patients without imaging improvement had relatively higher baseline levels of CCL22, FGF-2, and PDGF-AB (p = 0.056, p = 0.06 and p = 0.08 respectively) and lower baseline levels of TNFα, ESR, and CRP (p=0.04, p=0.056, p=0.07, respectively) compared with patients without it. Conclusion: GCs and TOF are effective in decreasing inflammatory molecules but have limited efficacy in regulating multiple other markers involved in TAK. PTX3 is a prominent marker for disease activity, and CCL22 may have a predictive value for vascular progression.