Objectives Synovial fibroblasts (SFs) are one of the major components of the inflamed synovium in rheumatoid arthritis (RA). We aimed to gain insight into the pathogenic mechanisms of SFs through elucidating the genetic contribution to molecular regulatory networks under inflammatory condition. Methods SFs from RA and osteoarthritis (OA) patients (n=30 each) were stimulated with eight different cytokines (interferon (IFN)-α, IFN-γ, tumour necrosis factor-α, interleukin (IL)-1β, IL-6/sIL-6R, IL-17, transforming growth factor-β1, IL-18) or a combination of all 8 (8-mix). Peripheral blood mononuclear cells were fractioned into five immune cell subsets (CD4⁺ T cells, CD8⁺ T cells, B cells, natural killer (NK) cells, monocytes). Integrative analyses including mRNA expression, histone modifications (H3K27ac, H3K4me1, H3K4me3), three-dimensional (3D) genome architecture and genetic variations of single nucleotide polymorphisms (SNPs) were performed. Results Unstimulated RASFs differed markedly from OASFs in the transcriptome and epigenome. Meanwhile, most of the responses to stimulations were shared between the diseases. Activated SFs expressed pathogenic genes, including CD40 whose induction by IFN-γ was significantly affected by an RA risk SNP (rs6074022). On chromatin remodelling in activated SFs, RA risk loci were enriched in clusters of enhancers (super-enhancers; SEs) induced by synergistic proinflammatory cytokines. An RA risk SNP (rs28411362), located in an SE under synergistically acting cytokines, formed 3D contact with the promoter of metal-regulatory transcription factor-1 (MTF1) gene, whose binding motif showed significant enrichment in stimulation specific-SEs. Consistently, inhibition of MTF1 suppressed cytokine and chemokine production from SFs and ameliorated mice model of arthritis. Conclusions Our findings established the dynamic landscape of activated SFs and yielded potential therapeutic targets associated with genetic risk of RA.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with diverse clinical manifestations that can lead to severe organ damage. The complex pathophysiology of SLE makes treatment selection difficult. This review examines the current evidence for biological therapies in SLE, including the anti-B cell activating factor antibody belimumab; the type I interferon receptor antagonist anifrolumab; the novel calcineurin inhibitor voclosporin; and rituximab, which targets CD20 on B cells. We also describe emerging therapies, including novel agents in development and CD19-directed chimeric antigen receptor (CAR) T cell therapy, which has shown promise in early clinical experience. Recent advances in biomarker research, including interferon signatures and transcriptomic profiles, may facilitate patient stratification and treatment selection. This review offers insights into current and future treatment strategies for patients with SLE by analyzing clinical trial results and recent immunological findings.

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

Clinically amyopathic dermatomyositis (CADM) patients frequently develop refractory interstitial lung disease (ILD), with a poor prognosis. We aimed to verify the efficacy and safety of plasma exch...

Rheumatoid arthritis (RA) is an autoimmune disease characterized by destructive synovitis. It is significantly associated with disability, impaired quality of life, and premature mortality. Recently, the development of biological agents (including tumor necrosis factor-α and interleukin-6 receptor inhibitors) and Janus kinase inhibitors have advanced the treatment of RA; however, it is still difficult to predict which drug will be effective for each patient. To break away from the current therapeutic approaches that could be described as a “lottery,” there is an urgent need to establish biomarkers that stratify patients in terms of expected therapeutic responsiveness. This review deals with recent progress from multi-faceted analyses of the synovial tissue in RA, which is now bringing new insights into diverse features at both the cellular and molecular levels and their potential links with particular clinical phenotypes.

Limbic encephalitis (LE) is a clinically defined syndrome characterized by an acute or subacute impairment of short-term memory, seizures and psychiatric symptoms (i.e., depression, anxiety and hallucination). LE could come from certain conditions where the neuropsychiatric systemic lupus erythematosus (NPSLE) of the multiple central nervous system is layered. In this report, we describe a 46-year-old Japanese female with SLE that suddenly presented with seizures, sensory aphasia and pseudobulbar affect. She was diagnosed with severe NPSLE presenting clinical LE (LE-SLE) by excluding malignancies, infectious encephalitis and symptomatic epilepsy using diffusion-weighted magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT). The patient showed a rapid response to treatment with methylprednisolone pulses followed by high-dose prednisolone and intravenous cyclophosphamide. She had elevated anti-glutamate receptor antibodies (anti-GluRs) in her serum and cerebrospinal fluid (CSF) on admission, and the titers decreased to a normal range at a one-year follow up. Our case highlights the importance of measuring anti-neuron antibodies including anti-GluRs in NPSLE patients, and suggests that the reduction of these pathogenic autoantibodies in serum or CSF could be a prognostic marker.