Studies conducted using murine arthritis models have indicated that the use of in vitro-transcribed messenger RNA (IVT mRNA) is an effective therapeutic approach for joint diseases. However, the use ...of IVT mRNA in human synovial cells has not been widely studied. Recently, the outbreak of the novel coronavirus disease has accelerated the development of innovative mRNA vaccines, such as those containing a modified nucleic acid, N
1
-methylpseudouridine-5′-triphosphate (m1ψ). IVT mRNA is an attractive tool for biological experiments and drug discovery. To verify the protein expression from IVT mRNA in vitro, primary cultured fibroblast-like synoviocytes (FLS) and MH7A human synovial fibroblast cells were transfected with enhanced green fluorescent protein (EGFP) mRNA with or without m1ψ incorporation. EGFP was detected using western blotting and fluorescence microscopy. A multiplex assay was performed to comprehensively understand IVT mRNA-induced immunogenicity. Gene expression levels were measured using reverse transcription polymerase chain reaction. In both MH7A cells and FLS, cells transfected with EGFP mRNA containing m1ψ generated higher levels of EGFP than those transfected with unmodified EGFP or control mRNAs. The multiplex assay of the FLS culture supernatant and reverse transcription polymerase chain reaction for FLS revealed that both concentration and expression of IL-6, TNF-α, and CXCL10 were upregulated by unmodified EGFP mRNA, whereas they were suppressed by EGFP mRNA with m1ψ. Overall, m1ψ incorporation enhanced protein expression and decreased the expression of cytokines. These findings may contribute to arthritis research.
Abstract
Objectives
This study aimed to quantify nailfold capillary (NFC) abnormalities in anti–melanoma differentiation–associated gene 5 (MDA5) -positive DM patients and to evaluate the association ...with clinical parameters, including serum biomarkers. In addition, we aimed to clarify the period leading to remission of NFC abnormalities during immunosuppressive treatment in patients with DM.
Methods
A prospective observational study was conducted including patients (n = 10) who first visited Hiroshima University Hospital and were diagnosed with DM or clinically amyopathic DM with anti-MDA5 antibodies. We compared the NFC abnormalities detected by nailfold-video capillaroscopy (NVC), physical findings, blood tests, respiratory function tests, and vascular-related growth factors measured using a LEGENDplexTM Multi-Analyte Flow Assay Kit.
Results
NFC abnormalities improved in all patients from 2 to 17 weeks after the initiation of immunosuppressive treatment. The NVC scores were inversely correlated with anti-MDA5 antibody titres at baseline. NVC scores and forced vital capacity were positively correlated. Baseline values of M-CSF and stem cell factor were correlated with anti-MDA-5 titres.
Conclusion
Our study suggested that NVC scores and disease activity were inversely correlated before treatment. Vascular-related growth factors, such as M-CSF and stem cell factor, may be associated with the disease mechanism in patients with anti-MDA5 antibody-positive DM.
Objective This study explored the predictors of hydroxychloroquine intolerance and propose appropriate methods to initiate hydroxychloroquine in patients with systemic lupus erythematosus. Methods ...This retrospective study registered consecutive patients who were diagnosed with systemic lupus erythematosus and started treatment with hydroxychloroquine between 2015 and 2021. Any adverse events that required dose reduction or cessation of hydroxychloroquine, indicating intolerance to the drug, were recorded for up to 26 weeks after initiation of hydroxychloroquine. Results A total of 130 patients were included. Hydroxychloroquine intolerance due to adverse drug reactions was observed in 28 patients (21.5%), including gastrointestinal symptoms in 15 (11.5%) and cutaneous reactions in 7 (5.4%). Furthermore, the intolerance was observed more frequently in the maintenance group (patients treated daily with <20 mg prednisolone) than in the induction group (7.1% vs. 25.5%, p=0.04), and none of the patients in the induction group developed cutaneous reactions. The initial dose of hydroxychloroquine per ideal body weight was associated with hydroxychloroquine intolerance in a dose-dependent manner. Multivariable analyses revealed that the hydroxychloroquine dose per ideal body weight and higher levels of C4 predicted hydroxychloroquine intolerance. In particular, C4 levels were positively correlated with cutaneous reactions, whereas the dose of prednisolone was negatively correlated with gastrointestinal reactions. Conclusion Low-dose hydroxychloroquine may be optimal for induction in patients with systemic lupus erythematosus who have high C4 levels or are taking low doses of steroids.
A 72-year-old woman had a history of chronic hepatitis C virus (HCV) infection previously treated with interferon to achieve a sustained virologic response. Thereafter, she developed polyarthritis ...and purpura of the lower extremities as well as progressive renal dysfunction with hypertension and proteinuria that had occurred in the last three months. Laboratory investigations revealed seropositivity for cryoglobulin but negative findings for HCV RNA. She was ultimately diagnosed with cryoglobulinemic glomerulonephritis complicated by monoclonal gammopathy of undetermined significance (MGUS) based on the pathological findings of the kidney and bone marrow, indicating that MGUS-induced cryoglobulinemic vasculitis may occur even after HCV elimination.
Blood coagulation factor XIII (FXIII) promotes cross-linking between fibrin molecules at the final stage of the blood coagulation cascade. However, its expression in cells or tissues and function, ...particularly factor XIII subunit B (FXIII-B), remains controversial. Hemorrhagic FXIII deficiency following anti-interleukin-6 (IL-6) receptor antibody treatment has been reported in patients with rheumatoid arthritis (RA). Patients receiving this biologics have reduced FXIII activity when compared to the activity in those treated with other biologics. The relationship between pro-inflammatory cytokines and FXIII expression remains unknown.
To investigate the expression pattern of FXIII in synovial tissues, immunohistochemistry, RT-qPCR, and western blotting were performed. FXIII-A expressed monocyte-derived macrophages were treated with recombinant IL-6 and anti-IL-6 receptor antibody. RNA sequencing of FXIII-B-overexpressing cells was performed to clarify the function of FXIII-B.
The immunohistochemical analysis of synovial tissues revealed that factor XIII subunit A (FXIII-A) was expressed in M2 macrophages, and FXIII-B was expressed in fibroblast-like synoviocytes. IL-6 stimulation upregulated FXIII-A expression in IL-4-induced monocyte-derived macrophages, and the anti-IL-6 receptor antibody suppressed FXIII-A expression. FXIII-B was more abundantly secreted in the supernatant of fibroblast-like synoviocytes compared with that of other cells. RNA sequencing showed that FXIII-B elevated the expression of genes associated with anti-apoptotic molecules and chemokines.
Our findings highlight that synovial tissue is one of the sources of FXIII production. We also have demonstrated IL-6-dependent FXIII-A expression and the novel potential functions of FXIII-B.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), utilizes the host receptor angiotensin-converting enzyme 2 (ACE2) and the auxiliary ...receptor Neuropilin-1 (NRP1) to enter host cells. NRP1 has another isoform, NRP2, whose function in COVID-19 has seldom been reported. In addition, although patients with severe cases of COVID-19 often exhibit increased levels of proinflammatory cytokines, the relationship between these cytokines and SARS-CoV-2 proliferation remains unknown. The aim of this study is to clarify the roles of proinflammatory cytokines in Neuropilin expressions and in SARS-CoV-2 infection. To identify the expression patterns of NRP under inflamed and noninflamed conditions, next-generation sequencing (RNA-seq), immunohistochemistry, quantitative real-time PCR, and Western blotting were performed using primary cultured fibroblast-like synoviocytes, MH7A (immortalized cell line of human rheumatoid fibroblast-like synoviocytes), immortalized MRC5 (human embryonic lung fibroblast), and synovial tissues. To measure viral proliferative capacity, SARS-CoV-2 infection experiments were also performed. NRP2 was upregulated in inflamed tissues. Cytokine-stimulated human fibroblast cell lines, such as MH7A and immortalized MRC5, revealed that NRP2 expression increased with co-stimulation of tumor necrosis factor α (TNFα) and interleukin-1 beta (IL-1β) and was suppressed with anti-TNFα antibody alone. TNFα and IL-1β promoted SARS-CoV-2 proliferation and Spike protein binding. The viral proliferation coincided with the expression of NRP2, which was modulated through plasmid transfections. Our results revealed that proinflammatory cytokines, including TNFα, contribute to NRP2 upregulation and SARS-CoV-2 proliferation in host human cells.
Objectives We investigated the current perspectives regarding the management of late-onset rheumatoid arthritis (LORA) among rheumatologists in clinical practice. Methods This study was performed in ...October 2021, and included 65 rheumatologists certified by the Japan College of Rheumatology, who were administered questionnaires (including multiple choice and descriptive formulae) regarding the management of LORA. We aggregated and analyzed the responses. Results All 65 rheumatologists responded to the survey; 47 (72%) answered that >50% of newly diagnosed patients were aged ≥65 years, 42 (65%) answered that achievement of remission or low disease activity was the treatment goal, and 40 (62%) considered patient safety to be the highest priority. Most rheumatologists are concerned about the management of conditions other than RA, such as comorbidities, financial constraints, and life circumstances that interfere with standard or recommended treatment implementation. Conclusion This preliminary survey highlighted various rheumatologists' perspectives regarding the management of LORA.
Lipopolysaccharide (LPS) contamination of commercially available proteins has seriously impeded research on citrullinated fibrinogen (cit-Fb) in rheumatoid synovial cells (RSCs).
RSCs obtained from 4 ...rheumatoid arthritis patients who underwent full knee arthroplasty were cultured, stimulated with cit-Fb, and cytokine expression levels were measured. We then evaluated polymyxin-B (PMB), heat inactivation, and rough (R)-type LPS mutants for rapid detection of LPS contamination.
cit-Fb induced expression of CXCL10 and IFNB in RSCs via the toll-like receptor. PMB inhibited cit-Fb-mediated CXCL10 gene expression but not protein expression induced by 20 μg/mL cit-Fb. Heat inactivation did not affect LPS-mediated CXCL10 or IL-6 induction; however, cit-Fb-mediated CXCL10expression was inhibited. Wild-type LPS from Escherichia coli (WT-LPS) strongly induces CXCL10 expression, but induction by Ra-LPS was weak, and induction by Rc- and Re-LPS was minimal. Re-LPS suppression of WT-LPS-mediated CXCL10 induction in RSCs and peripheral blood monocytes (PBMs) was dose dependent. Furthermore, Re-LPS completely suppressed cit-Fb-mediated CXCL10 induction in RSCs and PBMs.
To easily identify LPS contamination during routine experiments, our results suggest that Re-LPS is a better tool for rapid detection of LPS contamination compared to PMB and heat treatment.
