Despite similarities in the involved organs, there are considerable clinical and pathological differences between IgG(4)+MOLPS and SS. Based on the clinical features and good response to glucocorticoids, we propose a new clinical entity: IgG(4)+MOLPS.

Objective Interstitial lung disease (ILD) accompanied by anti–melanoma differentiation–associated gene 5 (anti–MDA‐5)–positive dermatomyositis (DM) is often rapidly progressive and associated with poor prognosis. Because there is no established treatment, we undertook this study to prospectively evaluate the efficacy and safety of a combined immunosuppressive regimen for anti–MDA‐5–positive DM patients with ILD. Methods Adult Japanese patients with new‐onset anti–MDA‐5–positive DM with ILD (n = 29) were enrolled at multiple study centers from 2014 to 2017. They were treated with a regimen of high‐dose glucocorticoids (GCs), tacrolimus, and intravenous cyclophosphamide (IV CYC). Plasmapheresis was used if a patient's condition worsened after the regimen started. The primary end point was 6‐month survival, which was compared between this group of patients and a historical control group (n = 15) consisting of anti–MDA‐5–positive DM patients with ILD who received step‐up treatment (high‐dose GC and stepwise addition of immunosuppressant). Secondary end points were 12‐month survival rate, adverse events, and changes in laboratory data. Results The combined immunosuppressive regimen group showed significantly higher 6‐month survival rates than the step‐up treatment group (89% versus 33%; P < 0.0001). Over a period of 52 weeks, improvements in anti–MDA‐5 titers, serum ferritin levels, vital capacity, and chest high‐resolution computed tomography scores were observed. The combined immunosuppressive regimen group received IV CYC nearly 20 days earlier with shorter intervals and tended to receive plasmapheresis more often than patients undergoing step‐up treatment. Cytomegalovirus reactivation was frequently observed over 52 weeks. Conclusion A combined immunosuppressive regimen is effective for anti–MDA‐5–positive DM patients with ILD. Plasmapheresis can be used for additional effect in intractable disease. Patients should be carefully monitored for opportunistic infections during treatment.

The WW domain-containing protein 2 ( Wwp2 ) gene, the host gene of miR-140, codes for the Wwp2 protein, which is an HECT-type E3 ubiquitin ligases abundantly expressed in articular cartilage. However, its function remains unclear. Here, we show that mice lacking Wwp2 and mice in which the Wwp2 E3 enzyme is inactivated (Wwp2-C838A) exhibit aggravated spontaneous and surgically induced osteoarthritis (OA). Consistent with this phenotype, WWP2 expression level is downregulated in human OA cartilage. We also identify Runx2 as a Wwp2 substrate and Adamts5 as a target gene, as similar as miR-140. Analysis of Wwp2-C838A mice shows that loss of Wwp2 E3 ligase activity results in upregulation of Runx2-Adamts5 signaling in articular cartilage. Furthermore, in vitro transcribed Wwp2 mRNA injection into mouse joints reduces the severity of experimental OA. We propose that Wwp2 has a role in protecting cartilage from OA by suppressing Runx2-induced Adamts5 via Runx2 poly-ubiquitination and degradation.

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Bradykinin (BK) is a major kinin with well-documented pharmacological properties including vascular leakage and induction of a variety of cytokines. However, the intracellular signalling mechanisms by which BK induced proinflammatory cytokine production have not been fully elucidated. This study investigated the role of the extracellular signal-regulated protein kinase 1/2 (ERK 1/2) and p38 mitogen-activated protein kinase (p38 MAPK) in the BK-induced interleukin (IL)-6 and IL-8 production by human lung fibroblasts.Lung fibroblasts were stimulated with BK in the presence or in the absence of PD98059, a specific MAPK/ERK kinase-1 inhibitor, or SB203580, a specific p38 MAPK inhibitor, and IL-6 or IL-8 production and their gene expression was examined. BK-induced ERK 1/2 or p38 MAPK phosphorylation was also analysed by Western blot analysis.BK at nanomolar concentrations stimulated lung fibroblasts to produce IL-6 and IL-8 along with increased ERK 1/2 and p38 MAPK phosphorylation. BK-induced IL-6 and IL-8 synthesis was inhibited by a B2-type BK receptor antagonist. Furthermore, PD98059 or SB203580 significantly suppressed BK-induced IL-6 and IL-8 production and their gene expression.These results indicate that bradykinin-induced interleukin-6 and interleukin-8 production are at least partly mediated through the extracellular signal-related protein kinase 1/2 and p38 mitogen-activated protein kinase pathway-dependent activation in human lung fibroblasts, and suggest that bradykinin appears to be involved in the inflammatory reaction leading to acute lung injury through stimulating interleukin-6 and interleukin-8 production by lung fibroblasts. Eur Respir J 2000; 16: 452±458.