BackgroundAdult-onset Still’s disease (AOSD) is a systemic inflammatory disease characterized by neutrophilia and NLRP3 inflammasome and macrophage activation. We investigated the role of neutrophil extracellular traps (NETs) in the pathogenesis of AOSD, and explored the effect of NETs on activating NLRP3 inflammasome and proinflammatory macrophages.MethodsThe sera of 73 AOSD patients and 40 healthy controls were used to detect the level of cell-free DNA and NET-DNA complexes. NET formation ex vivo was analyzed using immunofluorescence and flow plates. The activation of NLRP3 inflammasome in THP-1 cells and proinflammatory macrophages stimulated with DNA purified from NETs was measured using RT-PCR, ELISA, Western blotting and flow cytometry.ResultsThe levels of cell-free DNA and NET-DNA complexes were significantly increased in the circulation of patients with AOSD compared with healthy controls, and freshly isolated neutrophils from patients with AOSD were predisposed to high levels of spontaneous NET release. Interestingly, enhanced NET release was abrogated with NADPH oxidase inhibitors and a mitochondrial scavenger. Furthermore, DNA purified from AOSD NETs activated NLRP3 inflammasomes. NET DNA from AOSD also exerted a potent capacity to accelerate the activation of CD68+CD86+ macrophages and increased the expression of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α. Finally, the copy number of mitochondrial DNA (mtDNA) in NETs and plasma was significantly increased in AOSD patients, suggesting that mtDNA may be involved in the activation of NLRP3 and inflammatory macrophages.ConclusionsThese findings implicate accelerated NET formation in AOSD pathogenesis through activation of NLRP3 and proinflammatory macrophages, and identify a novel link between neutrophils and macrophages by NET formation in AOSD.Electronic supplementary materialThe online version of this article (10.1186/s13075-018-1800-z) contains supplementary material, which is available to authorized users.

Anti-PS/PT antibody assays demonstrated high diagnostic performance for Chinese patients with APS, detected some APS patients negative for criteria markers and may serve as potential risk predictors for venous thrombosis and obstetric complications.

Background: Despite expansion in the 2006 Sydney antiphospholipid syndrome (APS) classification criteria to include IgG/IgM anti-β2-glycoprotein (aβ2GPI) antibodies in addition to IgG/IgM anti-cardiolipin antibodies (aCL) and lupus anticoagulant (LAC), some individuals with clinical features of APS remain seronegative (seronegative APS or SNAPS) and are at risk of recurrent thrombosis and pregnancy morbidities. Our aim was to assess the value of "non-criteria" aPL antibodies to detect these SNAPS patients.Methods: One hundred ninety-two APS patients, 90 SNAPS patients, 193 autoimmune disease controls, and 120 healthy controls were evaluated. Ten antiphospholipid antibodies (aPLs) were tested using commercial kits, including 5 non-criteria aPLs: anti-phosphatidylserine/prothrombin antibodies (aPS/PT) IgG/IgM, aCL IgA, aβ2GPI IgA, and anti-β2GPI Domain 1 (aβ2GPI-D1) IgG. Results: Up to 60.9% of the SNAPS and 93.5% of APS patients were detected by at least one non-criteria aPL. aPS/ PT IgG had the highest Youden index in classifying APS and SNAPS from controls. aPS/PT IgG and aβ2GPI Domain 1 IgG seem to be the most significant risk factors for thrombotic events and pregnancy morbidity, respectively. aPS/ PT IgG/IgM and aβ2GPI-D1 IgG were detected in some SNAPS patients, while IgA isotypes of aCL/aβ2GPI tended to appear together with other biomarkers. The combined analysis showed enhanced diagnostic performance with the inclusion of non-criteria aPLs. Conclusions: Recognition of SNAPS patients is critical for clinical management and prevention of potential thrombotic and obstetric adverse events. The non-criteria antiphospholipid antibodies help to identify a considerable portion (60.9%) of these patients who otherwise may remain untreated and at clinical risk.

Objective: Adult-onset Still's disease (AOSD) is a rare but clinically well-known polygenic systemic autoinflammatory disease. In this review, we aim to present frontiers in the pathogenesis, clinical features, diagnosis, biomarkers, disease course, prognosis, and treatment in AOSD. Data sources: We retrieved information from the PubMed database up to July 2019, using various search terms and relevant words, including AOSD and Still's disease. Study selection: We included data from peer-reviewed journals. Both basic and clinical studies were selected. Results: Pathogenesis of AOSD involves genetic background, infectious triggers, and immunopathogenesis, mainly the activation of macrophages and neutrophils followed by a cytokine storm. Diagnosis and prognosis evaluation of AOSD is still challenging; therefore, there is an urgent need to identify better biomarkers. Biologic agents, including interleukin (IL)-1β, IL-6, and tumor necrosis factor-α antagonists in the treatment of AOSD, have good prospect. Conclusion: This review highlights the advances in pathogenesis, potential biomarkers, disease course, and treatment in AOSD.

BackgroundInflammation plays a vital role in the pathogenesis in lupus nephritis (LN), which is largely attributable to the activation of nuclear factor kappa B (NF-κB) signal pathway. NF-κB up-regulates pro-inflammatory mediators, such as TNF-α, cyclo-oxygenase-2 (COX-2) and ICAM-1, and promotes macrophage infiltration into renal tissue, further inducing the progression of LN. Over the past 30 years, research has demonstrated that Tripterygium wilfordii Hook F (TWHF) possesses potent anti-inflammatory and immunosuppressive activities, and that demethylzeylasteral (T-96), an extract of TWHF, may be one of the responsible compounds. Here, we investigate the pharmacodynamic role and therapeutic mechanism by which T-96 suppresses inflammation and reduces renal pathology in the lupus-prone MRL/lpr mice.MethodsForty-eight MRL/lpr mice were equally randomly divided into 6 groups (1.2, 0.6 or 0.3 mg/10g T-96, 0.022 pills/10g kang lang chuang san (one of Traditional Chinese herb as positive control), 0.125 mg/10g prednisone and 0.1 ml/10g normal saline as the LN disease control group). Also, eight WT C57BL/6 mice were used as normal control. After treatment by gavage with 0.10 ml/10g/day volumes for 8 weeks, all mice were sacrificed and renal tissues were collected. The amount of 24 h proteinuria and the levels of anti-dsDNA antibody in serum were assessed respectively at weeks 0, 4 and 8. Inflammation, cytokines and NF-κB levels were assessed by histological examinations, immunohistochemical analyses and Western blot analyses.ResultsIn comparison with untreated MRL/lpr mice, mice treated with 1.2 and 0.6 mg/10g of T-96 showed a significant improvement in 24 h proteinuria and the levels of anti-dsDNA antibody in serum. In addition, T-96 reduced the secretion of pro-inflammatory mediators such as TNF-α, COX-2 and ICAM-1, and the infiltration of macrophages in renal tissue. Moreover, T-96 significantly suppressed phosphorylations of cytoplasmic IKK and nuclear p65.ConclusionThis study suggests that T-96 exhibits reno-protective effects in LN accompanied by inhibiting the activation of NF-κB, reducing the downstream pro-inflammatory mediators and thus restricting macrophage infiltration. Because of these potent properties, T-96 should be considered as a promising therapeutic drug for LN.

To estimate the mortality and describe the causes of death in a large multicenter cohort of hospitalized patients with SLE in China. This was a retrospective study of a nationwide SLE cohort (10 centers, 29,510 hospitalized patients) from 2005 to 2014 in China. Standardized mortality ratios (SMRs) were calculated for all death and were stratified by sex and age. Chi-square test was used to determine whether the major causes of death vary in age, sex, duration of SLE, disease activity, or medications. Comparison between dead patients and survival controls was used to identify the risk factors for mortality. Logistic regression analysis was used to evaluate the risk factors for mortality. A total of 360 patients died during the study period, accounting for 1.22%. The overall SMR was 2.13 (95% CI 1.96, 2.30), with a particularly high SMR seen in subgroups characterized by younger age. Infection (65.8%) was the most common cause of death, followed by lupus nephritis (48.6%), hematological abnormality (18.1%), neuropsychiatric lupus/NPSLE (15.8%), and interstitial pneumonia (13.1%). Cardiovascular disease and malignancy contributed little to the causes of death. Infection, in particular severe pulmonary infection, emerged as the foremost risk factor for mortality, followed by lupus encephalopathy. However, lupus nephritis and hematological abnormalities occurred more frequently in survival patients. SLE patients at a younger age of diagnosis have a poorer prognosis. Infection dominated the causes of death in recent China. Ethnicity and medications might account for the differences in causes of death compared with western populations.

BackgroundInterleukin (IL)-37 has been known to play an immunosuppressive role in various inflammatory disorders, but whether it participates in the regulation of pathogenesis of adult-onset Still’s disease (AOSD) has not been investigated. In this study, we examined serum IL-37 levels and their clinical association with AOSD, and we explored the anti-inflammatory effects of IL-37 on peripheral blood mononuclear cells (PBMCs) from patients with AOSD.MethodsBlood samples were collected from 62 patients with AOSD and 50 healthy control subjects (HC). The serum IL-37 levels were determined using an enzyme-linked immunosorbent assay (ELISA). The correlations of serum IL-37 levels with disease activity, laboratory values, and inflammatory cytokines in AOSD were analyzed by Spearman’s correlation test. The correlations between serum IL-37 levels and clinical manifestations were analyzed by Mann-Whitney U test. PBMCs from ten patients with AOSD were stimulated with recombinant human IL-37 protein, and expression levels of tumor necrosis factor (TNF)-α, IL-6, IL-10, IL-1β, and IL-18 were determined by qRT-PCR and ELISA.ResultsA significantly higher IL-37 protein level was observed in patients with AOSD than in HC. Serum IL-37 levels correlated with systemic score, laboratory values, IL-1β, IL-18, and IL-10 in patients with AOSD. The expression levels of IL-37 were closely related to the patients with AOSD who also had fever, skin rash, lymphadenopathy, splenomegaly, myalgia, and arthralgia. Moreover, the production of proinflammatory cytokines such as IL-6, IL-1β, TNF-α, and IL-18 in PBMCs from patients with AOSD was obviously attenuated after recombinant human IL-37 stimulation.ConclusionsIncreased expression of IL-37 and its positive correlation with disease activity suggest its involvement in AOSD pathogenesis. More importantly, IL-37 inhibits the expression of proinflammatory cytokines in PBMCs from patients with AOSD, indicating the potential anti-inflammatory role of IL-37 in AOSD. Thus, IL-37 may be a novel disease activity biomarker and research target in AOSD.Electronic supplementary materialThe online version of this article (10.1186/s13075-018-1555-6) contains supplementary material, which is available to authorized users.

Industrial poly(vinyl chloride) (PVC) plastisols are often formulated using phthalate plasticizers due to their costeffectiveness and high compatibility with PVC. However, there is a current need to replace these additives by plasticizers that (i) present reduced migration/leaching and volatilization profiles, (ii) can optimize production processes while maintaining the performance of the final plasticized materials, and (iii) reduce toxicological risks to consumers and to the environment. The main objective of this work was to evaluate the effects of the partial replacement (15 and 30% (w/w)) of two conventional plasticizers (diisononyl phthalate (DINP) and acetyltri-2-ethylhexyl citrate (CITROFOL AHII)) by two low-volatility ionic liquids of the phosphonium-type (trihexyl(tetradecyl) phosphonium dicyanamide and trihexyl(tetradecyl) phosphonium bis-(trifluoromethylsulfonyl)imide) on the rheological and thermomechanical properties of an emulsion-grade PVC which is usually employed in the production of automotive industry upholsteries. Rheological profiles and plastisols' particle size distributions were monitored over time (up to 14 days) to study the effects of plastisols aging on the thermal stability and thermomechanical properties of PVC films obtained after gelation of the plastisols. Obtained results showed that the incorporation of these two phosphonium-type ionic liquids into DINP-and CITROFOL-based PVC plastisols significantly reduced their viscosities and changed their rheological profiles (from pseudoplastic to near-Newtonian behavior). Plastisols aging had a noticeable impact on the final thermomechanical properties of PVC films plasticized with DINP while no significant effects were observed for films plasticized with CITROFOL. These results are in good agreement with the correspondent timedependent rheological profiles.