Objective To compare the treatment efficacy and safety of tofacitinib (TOF) versus methotrexate (MTX) in Takayasu arteritis (TAK). Methods Fifty-three patients with active disease from an ongoing prospective TAK cohort in China were included in this study. Twenty-seven patients were treated with glucocorticoids (GCs) and TOF, and 26 patients were treated with GCs with MTX. The observation period was 12 months. Complete remission (CR), inflammatory parameter changes, GCs tapering and safety were assessed at the 6th, 9th and 12th month. Vascular lesions were evaluated at the 6th and 12th month, and relapse was analysed during 12 months. Results The CR rate was higher in the TOF group than in the MTX group (6 months: 85.19% vs 61.54%, p=0.07; 12 months: 88.46% vs 56.52%, p=0.02). During 12 months’ treatment, patients in the TOF group achieved a relatively lower relapse rate (11.54% vs 34.78%, p=0.052) and a longer median relapse-free duration (11.65±0.98 vs 10.48±2.31 months, p=0.03). Average GCs dose at the 3rd, 6th and 12th month was lower in the TOF group than that in the MTX group (p0.05). Prevalence of side effects was low in both groups (3.70% vs 15.38%, p=0.19). Conclusion TOF was superior to MTX for CR induction, a tendency to prevent relapse and tapering of the GCs dose in TAK treatment. A good safety profile for TOF was also documented in patients with TAK.

Background: Takayasu arteritis (TAK) is characterized by pro-inflammatory M1 macrophage infiltration and increased interferon (IFN)-γ expression in vascular lesions. IFN-γ is a key cytokine involved in M1 polarization. Macrophage polarization is accompanied by metabolic changes. However, the metabolic regulation mechanism of IFN-γ in M1 macrophage polarization in TAK remains unclear. Methods: Immunohistochemistry and immunofluorescence were employed to observe the expression of IFN-γ, PFKFB3 (6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3, the rate-limiting enzyme in glycolysis), and macrophage surface markers in the vascular tissue. Monocyte-derived macrophages from patients with TAK were cultured to examine the role of PFKFB3 in IFN-γ-induced M1 macrophage polarization. Seahorse analysis was used to detect the alterations in glucose metabolism during this process. Quantitative reverse transcription PCR, flow cytometry, and western blot were used to confirm the phenotypes of macrophages and related signaling pathways. Results: In the vascular adventitia of patients with TAK, an increase in PFKFB3 accompanied by IFN-γ expression was observed in M1 macrophages. In vitro, IFN-γ successfully induced macrophage differentiation into the M1 phenotype, which was manifested as an increase in CD80 and HLA-DR markers and the pro-inflammatory cytokines IL-6 and TNF-α. During this process, PFKFB3 expression and glycolysis levels were significantly increased. However, glycolysis and M1 polarization induced by IFN-γ were suppressed by a PFKFB3 inhibitor. In addition, JAK2/STAT1 phosphorylation was also enhanced in macrophages stimulated by IFN-γ. The effects of IFN-γ on macrophages, including the expression of PFKFB3, glycolysis, and M1 polarization, were also inhibited by the JAK inhibitor tofacitinib or STAT1 inhibitor fludarabine. Conclusion: PFKFB3-mediated glycolysis promotes IFN-γ-induced M1 polarization through the JAK2/STAT1 signaling pathway, indicating that PFKFB3 plays an important role in M1 polarization mediated by IFN-γ; thus, PFKFB3 is a potential intervention target in TAK.

Background: The remarkable mechanisms of storiform fibrosis and the formation of high levels of IgG4 with a pathogenic germinal center (GC) in the inflammatory tissue of IgG4-RD remains unknown and may be responsible for the unsatisfactory therapeutic effect on IgG4-related diseases when using conventional therapy. Objectives: To investigate the mechanisms of interleukin 6 (IL-6) inducing fibroblasts to produce cytokines for pathogenic GC formation in the development of IgG4-related disease (IgG4-RD). Methods: The clinical data and laboratory examinations of 56 patients with IgG4-RD were collected. IL-6 and IL-6R expression in the serum and tissues of patients with IgG4-RD and healthy controls were detected by ELISA, immunohistochemistry, and immunofluorescence. Human aorta adventitial fibroblasts (AAFs) were cultured and stimulated with IL-6/IL-6 receptor (IL-6R). The effect of IL-6/IL-6R on AAFs was determined by Luminex assays. Results: The serum IL-6 and IL-6R levels were elevated in active IgG4-RD patients and IL-6 was positively correlated with the disease activity (e.g., erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], and IgG4-RD responder index). IL-6 and IL-6R expression in the tissue lesions of IgG4-related retroperitoneal fibrosis and IgG4-related sialadenitis patients were also significantly higher than that in the normal tissues. In addition, there is a relative abundance of myofibroblasts as well as IgG4⁺ plasma cells in the tissues of IgG4-related retroperitoneal fibrosis. α-SMA and B cell differentiation cytokines (i.e., B cell activating factor), and α-SMA and T follicular helper (Tfh) cell differentiation cytokines (e.g., IL-7, IL-12, and IL-23) were co-expressed in the local lesions. In vitro, IL-6/IL-6R significantly promoted the production of B cell activating factor, IL-7, IL-12, and IL-23 in AAFs in a dose-dependent manner. This effect was partially blocked by JAK1, JAK2, STAT3, and Akt inhibitors, respectively. Conclusions: In vitro IL-6/IL-6R trans-signaling in fibroblasts releases Tfh and B cell differentiation factors partially via the JAK2/STAT3, JAK1/STAT3, and JAK2/Akt pathways, which may be linked to the pathogenesis of IgG4-RD. This indicated that IL-6 and fibroblasts may be responsible for GC formation and fibrosis in the development of IgG4-RD. Blocking IL-6 with JAK1/2 inhibitors or inhibiting fibroblast proliferation might be beneficial for IgG4-RD treatment.

The transcription factor BTB and CNC homology 1(BACH1) has been linked to coronary artery disease risk by human genome-wide association studies, but little is known about the role of BACH1 in vascular smooth muscle cell (VSMC) phenotype switching and neointima formation following vascular injury. Therefore, this study aims to explore the role of BACH1 in vascular remodeling and its underlying mechanisms. BACH1 was highly expressed in human atherosclerotic plaques and has high transcriptional factor activity in VSMCs of human atherosclerotic arteries. VSMC-specific loss of Bach1 in mice inhibited the transformation of VSMC from contractile to synthetic phenotype and VSMC proliferation and attenuated the neointimal hyperplasia induced by wire injury. Mechanistically, BACH1 suppressed chromatin accessibility at the promoters of VSMC marker genes via recruiting histone methyltransferase G9a and cofactor YAP and maintaining the H3K9me2 state, thereby repressing VSMC marker genes expression in human aortic smooth muscle cells (HASMCs). BACH1-induced repression of VSMC marker genes was abolished by the silencing of G9a or YAP. Thus, these findings demonstrate a crucial regulatory role of BACH1 in VSMC phenotypic transition and vascular homeostasis and shed light on potential future protective vascular disease intervention via manipulation of BACH1.

To assess the value of contrast-enhanced ultrasonography (CEUS) for monitoring disease activity of Takayasu arteritis (TA). TA patients were recruited in a Chinese TA clinical center from January 2016 to September 2017. The physician global assessment was used as the referential standard for disease activity. Clinical data, acute phase reactants, and CEUS scans were simultaneously recorded at baseline and after a 3-month therapy. A total of 84 TA patients were enrolled, and 47 (55.95%) cases were active at baseline. Macaroni sign and entire artery involvement were characteristic findings of CEUS in TA. The average vascular full thickness of the carotid artery in active TA patients was significantly higher than that in inactive patients (2.36 ± 0.86 vs. 1.79 ± 0.49 mm; p = 0.001). Severe neovascularization (grade 2) was observed in 29 active cases (61.70%) and in 9 inactive cases (24.32%) (p = 0.001). Receiver operating characteristic analysis showed that the combination of CEUS parameters (cutoff of thickness was 1.75 mm or neovascularization grade 2) and erythrocyte sedimentation rate (ESR) (cutoff of 20 mm/H) could help differentiate between active and inactive TA patients with a sensitivity and specificity of 81.1% and 81.5%, respectively. Youdon’s index was 0.626. Furthermore, our study found that patients with decreased ESR and C-reactive protein (CRP) still had a progression of vascular wall inflammation at 3 months of follow-up. The evaluation of vascular inflammation by CEUS is more sensitive than acute phase reactants. Neovascularization can still be observed in the vascular lesion sites of those who have reached clinical remission after treatment. Thus, CEUS can be used as an alternative method to assess disease activity for TA patients.