Excessive IL-1β Research Articles

Effectiveness and safety of canakinumab in cryopyrin-associated periodic syndrome: a retrospective study in China

ObjectiveCryopyrin-associated periodic syndrome (CAPS) is characterized by excessive IL-1β release resulting in systemic and organ inflammation. As an anti-IL-1 agent, canakinumab has been approved with all CAPS phenotypes in USA and European countries. However, the use of canakinumab in CAPS in Chinese patients was rarely reported. In this study, we aimed to assess the effectiveness and safety of canakinumab in Chinese patients with CAPS.MethodsPatients with CAPS treated with canakinumab were included. Clinical data were collected retrospectively from medical records. Treatment response was evaluated by CAPS disease activity score, C-reactive protein (CRP), and/or serum amyloid A (SAA) levels. Data was analyzed at canakinumab initiation, at months 1, 3, 6, 9, and 12, or the last follow-up.ResultsA total of 10 CAPS patients were included. 40% of patients were males, the median age at disease onset was 2.5 (2.5, 6) days and the median duration of follow-up while on canakinumab was 22.5 (8.5, 27.5) months. 80% (8/10) of CAPS patients presented with moderate-severe disease activity before the canakinumab treatment. 30% (3/10) of patients required canakinumab dose increase to control disease activity. After treatments, 60% (6/10) of CAPS patients achieved complete remission without relapse and the rest showed minimal disease activity. Clinical symptoms such as fever and rash were improved significantly in most patients (80%). Although abnormal imaging in brain MRI remained in over half of those patients, neurological manifestations were all relieved. 60% (6/10) of patients received prednisone before starting canakinumab therapy and five of them discontinued prednisone later. The most common adverse event was infection (40%). No serious adverse events occurred during the treatment of canakinumab.ConclusionsCanakinumab may be effective and tolerable for Chinese CAPS patients, helping to reduce the dosage of corticosteroids. However, additional trials on large samples are required to further evaluate its efficacy and safety in China.

Germline HAVCR2/TIM-3 Checkpoint Inhibitor Receptor Deficiency in Recurrent Autoinflammatory Myocarditis

Myocarditis can be caused by viral infection, drug reaction or general inflammatory condition. To provide understanding on inflammatory myocarditis, we describe clinical, genetic, and immunological properties of a young male patient who suffered from recurrent myocarditis episodes since the age of four years. Electrocardiography, troponin I/T, echocardiography, myocardial magnetic resonance imaging and histological findings were consistent with recurrent myocarditis episodes. Homozygous c.245 A > G p.Tyr82Cys pathogenic variant in Hepatitis A Virus Cellular Receptor 2 (HAVCR2) gene encoding T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) receptor was found. Peripheral blood mononuclear cells were collected when the patient was asymptomatic; CD4+ and CD8+ T lymphoblasts, CD56+ natural killer cells and CD14+ monocytes were negative for surface TIM-3 expression. In vitro, TLR4 mediated interleukin-1β (IL-1β) response was high after LPS/ATP stimulation. Clinical symptoms responded to IL-1 receptor antagonist anakinra. TIM-3 p.Tyr82Cys CD4+ and CD8+ T cell proliferation in vitro was unrestrained. Findings on IL-2, interferon gamma, regulatory T cells, signal transducer and activator of transcription (STAT) 1, 3 and 4 phosphorylation, and PD-1 and LAG-3 checkpoint inhibitor receptor analyses were comparable to controls. We conclude that TIM-3 deficiency due to homozygous HAVCR2 c.245 A > G p.Tyr82Cys pathogenic variant in the patient described here is associated with autoinflammatory symptoms limited to early onset recurrent febrile myocarditis. Excessive IL-1β production and defective regulation of T cell proliferation may contribute to this clinical condition responsive to anakinra treatment.

Isoliquiritigenin inhibits NLRP3 inflammasome activation with CAPS mutations by suppressing caspase-1 activation and mutated NLRP3 aggregation.

The nucleotide-binding oligomerization domain leucine-rich repeat and pyrin domain containing 3 (NLRP3) inflammasome contributes to the development of inflammatory diseases. Cryopyrin-associated periodic syndrome (CAPS) is an autoinflammatory disease caused by NLRP3 gene mutations that results in excessive IL-1β production. We previously identified isoliquiritigenin (ILG), a component of Glycyrrhiza uralensis extracts, as a potent inhibitor of the NLRP3 inflammasome. Here, we aimed to investigate whether ILG inhibits the activation of NLRP3 inflammasome caused by NLRP3 gene mutations. We demonstrated that ILG significantly inhibited NLRP3 inflammasome-mediated lactate dehydrogenase (LDH) release and IL-1β production in two CAPS model THP-1 cell lines, NLRP3-D303N and NLRP3-L353P, in a dose-dependent manner. Interestingly, the NLRP3 inhibitor MCC950 inhibited LDH release and IL-1β production in NLRP3-D303N cells, but not in NLRP3-L353P cells. Western blotting and caspase-1 activity assays showed that ILG, as well as caspase inhibitors, including Z-VAD and YVAD, suppressed caspase-1 activation. Notably, ILG prevented cryo-sensitive foci formation of NLRP3 without affecting the levels of intracellular Ca2+. We concluded that ILG effectively prevents the constitutive activation of the inflammasome associated with NLRP3 gene mutations by inhibiting the aggregation of cryo-sensitive mutated NLRP3.

Tmem178 Negatively Regulates IL-1β Production Through Inhibition of the NLRP3 Inflammasome.

Inflammasomes modulate the release of bioactive interleukin (IL)-1β. Excessive IL-1β levels are detected in patients with systemic juvenile idiopathic arthritis (sJIA) and cytokine storm syndrome (CSS) with mutated and unmutated inflammasome components, raising questions on the mechanisms of IL-1β regulation in these disorders. To investigate how the NLRP3 inflammasome is modulated in sJIA, we focused on Transmembrane protein 178 (Tmem178), a negative regulator of calcium levels in macrophages, and measured IL-1β and caspase-1 activation in wild-type (WT) and Tmem178-/- macrophages after calcium chelators, silencing of Stim1, a component of store-operated calcium entry (SOCE), or by expressing a Tmem178 mutant lacking the Stromal Interaction Molecule 1 (Stim1) binding site. Mitochondrial function in both genotypes was assessed by measuring oxidative respiration, mitochondrial reactive oxygen species (mtROS), and mitochondrial damage. CSS development was analyzed in Perforin-/- /Tmem178-/- mice infected with lymphocytic choriomeningitis virus (LCMV) in which inflammasome or IL-1β signaling was pharmacologically inhibited. Human TMEM178 and IL1B transcripts were analyzed in data sets of whole blood and peripheral blood monocytes from healthy controls and patients with active sJIA. TMEM178 levels are reduced in whole blood and monocytes from patients with sJIA while IL1B levels are increased. Accordingly, Tmem178-/- macrophages produce elevated IL-1β compared with WT cells. The elevated intracellular calcium levels after SOCE activation in Tmem178-/- macrophages induce mitochondrial damage, release mtROS, and ultimately promote NLRP3 inflammasome activation. In vivo, inhibition of inflammasome or IL-1β neutralization prolongs Tmem178-/- mouse survival in LCMV-induced CSS. Down-regulation of TMEM178 levels may represent a marker of disease activity and help identify patients who could benefit from inflammasome targeting.

Methotrexate associated with nanoparticles decreases NLRC4 inflammasome expression in infarcted rat hearts

Abstract Abstract: Following myocardial infarction (MI), molecules released from necrotic myocytes sensitize nucleotide-binding receptors (NLRs), activate inflammasome complex, and initiate acute inflammatory process and interleukin (IL)-1β production, essential for tissue damage resolution. However, excessive IL-1β production impairs cardiac remodeling. After MI, IL-1β is released by the NLRP3 inflammasome; involvement of the NLRC4 inflammasome in post-MI remodeling has not been established. Methotrexate (MTX) carried by lipid core nanoparticles in low density emulsion (MTX-LDE) reduces post-MI inflammatory process and improves cardiac function in rodents. Purpose To evaluate the influence of early treatment with MTX-LDE on myocardial expression of NLRP3 and NLRC4 inflammasomes in infarcted rats. Methods Male Wistar rats were divided into three groups: control (Sham, n=6); MI (n=6); and MI treated with MTX-LDE (MI-MTX, n=6). MI was induced by ligation of the left anterior descending coronary artery. Twenty-four hours later, the MI-MTX group was treated with 1 mg/kg of MTX-LDE, intraperitoneally. Euthanasia was performed 72 hours after surgery under anaesthesia with ketamine and xylazine. Infarct size was assessed by histology. Myocardial expression of NLRC4, NLRP3, ASC, pro-caspase-1, caspase-1, pro-IL-1β and IL-1β was quantified by Western blotting. IL-1β concentration in serum and heart macerate supernatant was analyzed by ELISA. Statistical: ANOVA or Kruskal-Wallis; 5% significance level. Results Rats with MI lower than 30% of the left ventricle total area were excluded. Infarct size was larger in the MI-MTX group (43,8 ± 5,4) than MI (36,2 ± 6,22). NLRC4 and caspase-1 expression and IL-1β serum concentration were higher in MI than Sham and MI-MTX. Myocardial IL-1β concentration was higher in MI and MI-MTX than Sham and lower in MI-MTX than MI. NLRP3, ASC, pro-caspase-1, and IL-1β protein expression did not differ between groups. Conclusion Our study shows for the first time that NLRC4 inflammasome protein expression increases acutely after myocardial infarction in rats. Early treatment with nanoparticles-derived methotrexate reduces myocardial NLRC4 inflammasome expression and myocardial and serum IL-1β concentration.

IL-1β turnover by the UBE2L3 ubiquitin conjugating enzyme and HECT E3 ligases limits inflammation

The cytokine interleukin-1β (IL-1β) has pivotal roles in antimicrobial immunity, but also incites inflammatory disease. Bioactive IL-1β is released following proteolytic maturation of the pro-IL-1β precursor by caspase-1. UBE2L3, a ubiquitin conjugating enzyme, promotes pro-IL-1β ubiquitylation and proteasomal disposal. However, actions of UBE2L3 in vivo and its ubiquitin ligase partners in this process are unknown. Here we report that deletion of Ube2l3 in mice reduces pro-IL-1β turnover in macrophages, leading to excessive mature IL-1β production, neutrophilic inflammation and disease following inflammasome activation. An unbiased RNAi screen identified TRIP12 and AREL1 E3 ligases of the Homologous to E6 C-terminus (HECT) family in adding destabilising K27-, K29- and K33- poly-ubiquitin chains on pro-IL-1β. We show that precursor abundance determines mature IL-1β production, and UBE2L3, TRIP12 and AREL1 limit inflammation by shrinking the cellular pool of pro-IL-1β. Our study uncovers fundamental processes governing IL-1β homeostasis and provides molecular insights that could be exploited to mitigate its adverse actions in disease.

Four polysaccharides isolated from Poria cocos mycelium and fermentation broth supernatant possess different activities on regulating immune response

Four polysaccharide fractions were isolated and purified from the culture supernatant and mycelium of Poria cocos, and differences in their immunomodulatory activity were investigated. The average molecular weights of EPS-0M, EPS-0.1M, IPS-0M, and IPS-0.1M were 1.77 × 103, 2.01 × 103, 0.03 × 103 and 4.97 × 103 kDa, respectively. They all mainly consisted of 5 monosaccharides, including glucose, mannose, galactose, fucose and rhamnose, but with different molar ratios. At a dose of 50 μg/mL, EPS-0M, EPS-0.1M, and IPS-0.1M significantly increased the production of nitric oxide (NO), as well as the mRNA and protein levels of pro-inflammatory factors including interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) in RAW264.7 cells, suggesting that they enhanced macrophage-mediated innate immunity. Moreover, based on the in vitro inflammation model of lipopolysaccharide (LPS)-stimulated RAW264.7 cells, EPS-0M, EPS-0.1M and IPS-0M but not IPS-0.1M could inhibit the LPS-induced excessive inflammatory response, including NO, IL-6, TNF-α, IL-1β production and gene transcription. Interestingly, IPS-0M showed a relatively poor immunostimulatory effect, but had the strongest inhibitory effect against the LPS-induced RAW264.7 inflammatory response. Furthermore, our results indicate that the nuclear factor-kappa B (NF-κB) pathway is associated with the immunomodulatory effects of the polysaccharide samples on RAW264.7 cells. This study can provide a reference for the more targeted application of different polysaccharide components from Poria cocos for human health.

Exploring the potential of Lacticaseibacillus paracasei M11 on antidiabetic, anti-inflammatory, and ACE inhibitory effects of fermented dromedary camel milk (Camelus dromedaries) and the release of antidiabetic and anti-hypertensive peptides.

The goal of this investigation was to find antidiabetic peptides and inhibit angiotensin converting enzyme (ACE) in Lacticaseibacillus paracasei (M11) fermented dromedary camel milk (Camelus dromedaries). According to the findings, the rate of antidiabetic activity increased along with the incubation periods and reached its peak after 48 hr of fermentation. The inhibitions of α-amylase, α-glucosidase, and lipase were 80.75, 59.62, and 65.46%, respectively. The inhibitory activity of ACE was 78.33%, and the proteolytic activity was 8.90 mg/mL. M11 at 0.25 mg/mL effectively suppressed LPS-induced pro-inflammatory cytokines and their mediators such as NO, TNF-α, IL-6, and IL-1β in RAW 264.7 cells. The rate of inoculum in the optimization phase was 1.5-2.5%, and the greatest proteolytic activity was observed after 48 hr of fermentation. The investigation of the above property in the ultrafiltered fermented milk exhibited the highest antidiabetic and ACE inhibition activities in the 3kDa than 10kDa fractions. The molecular weight was determined employing SDS-PAGE, and the six-peptide sequences were identified using 2D gel electrophoresis. Due to its high proteolytic activity, the L. paracasei strain has been reported to be useful in the production of ACE-inhibitory and antidiabetic peptides. Amino acid sequences such from ɑ1, ɑ2, and β-caseins have been identified within fermented camel milk by searching on online databases, including BIOPEP (for antidiabetic peptides) and AHTPDB (for hypertension peptides) to validate the antidiabetic and ACE-inhibitory actions of several peptides. PRACTICAL APPLICATIONS: The study aims to identify antidiabetic peptides and inhibit ACE in dromedary camel milk fermented with Lacticaseibacillus paracasei M11. Maximum antidiabetic and ACE-inhibitory actions of the fermented camel milk were observed in 3kDa permeate fractions. Fermented camel milk significantly reduced the excessive TNF-α, IL-6, and IL-1β production in LPS-activated RAW 264.7 cells. RP-LC/MS was used to identify 6 bioactive peptides from dromedary fermented camel milk. This fermented camel milk could be used for the management of hypertension and diabetic related problems.

A comprehensive review on current understanding of bradykinin in COVID-19 and inflammatory diseases.

Bradykinin, a member of the kallikrein–kinin system (KKS), is a potent, short-lived vasoactive peptide that acts as a vasodilator and an inflammatory mediator in a number of signaling mechanisms. Bradykinin induced signaling is mediated through kinin B1 (BDKRB1) and B2 (BDKRB2) transmembrane receptors coupled with different subunits of G proteins (Gαi/Gα0, Gαq and Gβ1γ2). The bradykinin-mediated signaling mechanism activates excessive pro-inflammatory cytokines, including IL-6, IL-1β, IL-8 and IL-2. Upregulation of these cytokines has implications in a wide range of clinical conditions such as inflammation leading to fibrosis, cardiovascular diseases, and most recently, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In SARS-CoV-2 infection, bradykinin is found to be at raised levels and is reported to trigger a diverse array of symptoms. All of this brings bradykinin to the core point as a molecule of immense therapeutic value. Our understanding of its involvement in various pathways has expanded with time. Therefore, there is a need to look at the overall picture that emerges from the developments made by deciphering the bradykinin mediated signaling mechanisms involved in the pathological conditions. It will help devise strategies for developing better treatment modalities in the implicated diseases. This review summarizes the current state of knowledge on bradykinin mediated signaling in the diverse conditions described above, with a marked emphasis on the therapeutic potential of targeting the bradykinin receptor.

Placental IL‐1β impairs endothelial functions by reducing VE‐cadherin expression in PE

Preeclampsia (PE) is a pregnancy‐specific syndrome that affects 5~8% pregnancies and is a leading cause of maternal and neonatal morbidity and mortality, especially in low‐income and middle‐income countries. Widespread systemic inflammation and endothelial dysfunction are hallmarks of injury in PE, however, the molecular mechanisms linking inflammation and endothelial dysfunction remain largely unknown. We tested the hypothesis that placental IL‐1β impairs endothelial functions by inhibiting VE‐cadherin expression in PE. We found that NLRP3 inflammasome was overactivated in preeclamptic placenta, which induced more IL‐1β release. We also observed that IL‐1β significantly increased endothelial permeability of Human Umbilical Vein Endothelial Cells (HUVECs) in a dose‐response manner, and inhibition of IL‐1β receptor significantly attenuated the increase of endothelial permeability induced by IL‐1β. We further revealed that both mRNA and protein level of VE‐cadherin was reduced by IL‐1β in HUVECs. and overexpression of VE‐cadherin in endothelial cells reversed IL‐1β‐induced increase in endothelial permeability. Taken together, our preliminary data suggested that excessive placental IL‐1β significantly impaired endothelial functions by inhibiting VE‐cadherin expression.

Antioxidative, antimicrobial and anti-inflammatory activities and release of ultra-filtered antioxidative and antimicrobial peptides during fermentation of sheep milk: In-vitro, in-silico and molecular interaction studies

The antioxidative, antimicrobial, and anti-inflammatory properties of fermented sheep milk with L. fermentum (KGL4), as well as the generation of antioxidative and antimicrobial peptides, are evaluated in the study. Antioxidative and antibacterial activities in sheep milk fermented with KGL4 increased with incubation hours, along with varied antioxidative properties (ABTS assay: 35.12%, hydroxyl free radical scavenging assay: 29.12%, superoxide free radical scavenging activity: 36.38%). Antimicrobial activity of fermented sheep milk against E. faecalis (19 mm), S. typhimurium (15.67 mm), B. cereus (14 mm), and E. coli (13 mm) was also observed. Furthermore, after 48 h, the KGL4 showed maximum proteolysis (10.40 mg/ml) at 2.5% rate of addition sheep milk. The antioxidative and antimicrobial activities of fermented sheep milk fractions (3 kDa and 10 kDa permeates and retentates) were also investigated. The highest ABTS activity (26.90%) was found in 10 kDa permeate, whereas the 3 kDa retentate had higher hydroxyl free radical scavenging activity (69.20%) and 3 kDa permeate showed maximum superoxide free radical scavenging activity (32.85%). The 10 kDa retentate had shown maximum antimicrobial activity against S. typhimurium (13.67 mm) and E. faecalis (17.00 mm). Proteins spotted on 2D gel electrophoresis of KGL4 were varied from 10 to 70 kDa. RP-LC/MS was used to identify 5 novel peptide sequences from 2-D gel spots. Searches in the BIOPEP database confirmed the antioxidative and antimicrobial effects of the novel fermented sheep milk peptides. Fermented sheep milk with KGL4 (SMKGL4) significantly reduced excessive TNF-α, IL-6, & IL-1β production in LPS-activated RAW 264.7 cells.

Melatonergic signalling instructs transcriptional inhibition of IFNGR2 to lessen interleukin-1β-dependent inflammation.

BackgroundImmunotransmitters (e.g., neurotransmitters and neuromodulators) could orchestrate diverse immune responses; however, the elaborated mechanism by which melatonergic activation governs inflammation remains less defined.MethodsPrimary macrophages, various cell lines, and Pasteurella multocida (PmCQ2)‐infected mice were respectively used to illustrate the influence of melatonergic signalling on inflammation in vitro and in vivo. A series of methods (e.g., RNA‐seq, metabolomics, and genetic manipulation) were conducted to reveal the mechanism whereby melatonergic signalling reduces macrophage inflammation.ResultsHere, we demonstrate that melatonergic activation substantially lessens interleukin (IL)‐1β‐dependent inflammation. Treatment of macrophages with melatonin rewires metabolic program, as well as remodels signalling pathways which depends on interferon regulatory factor (IRF) 7. Mechanistically, melatonin acts via membrane receptor (MT) 1 to increase heat shock factor (Hsf) 1 expression through lowering the inactive glycogen synthase kinase (GSK3) β, thereby transcriptionally inhibiting interferon (IFN)‐γ receptor (IFNGR) 2 and ultimately causing defective canonical signalling events [Janus kinase (JAK) 1/2‐signal transducer and activator of transcription (STAT) 1‐IRF7] and lower IL‐1β production in macrophages. Moreover, we find that melatonin amplifies host protective responses to PmCQ2 infection‐induced pneumonia.ConclusionsOur conceptual framework provides potential therapeutic targets to prevent and/or treat inflammatory diseases associating with excessive IL‐1β production.

IL-1β Impacts Vascular Integrity and Lymphatic Function in the Embryonic Omentum.

The chromatin-remodeling enzyme BRG1 (brahma-related gene 1) regulates gene expression in a variety of rapidly differentiating cells during embryonic development. However, the critical genes that BRG1 regulates during lymphatic vascular development are unknown. We used genetic and imaging techniques to define the role of BRG1 in murine embryonic lymphatic development, although this approach inadvertently expanded our study to multiple interacting cell types. We found that omental macrophages fine-tune an unexpected developmental process by which erythrocytes escaping from naturally discontinuous omental blood vessels are collected by nearby lymphatic vessels. Our data indicate that circulating fibrin(ogen) leaking from gaps in omental blood vessels can trigger inflammasome-mediated IL-1β (interleukin-1β) production and secretion from nearby macrophages. IL-1β destabilizes adherens junctions in omental blood and lymphatic vessels, contributing to both extravasation of erythrocytes and their uptake by lymphatics. BRG1 regulates IL-1β production in omental macrophages by transcriptionally suppressing the inflammasome trigger RIPK3 (receptor interacting protein kinase 3). Genetic deletion of Brg1 in embryonic macrophages leads to excessive IL-1β production, erythrocyte leakage from blood vessels, and blood-filled lymphatics in the developing omentum. Altogether, these results highlight a novel context for epigenetically regulated crosstalk between macrophages, blood vessels, and lymphatics.

JMML tumor cells disrupt normal hematopoietic stem cells by imposing inflammatory stress through overproduction of IL-1β

AbstractDevelopment of normal blood cells is often suppressed in juvenile myelomonocytic leukemia (JMML), a myeloproliferative neoplasm (MPN) of childhood, causing complications and impacting therapeutic outcomes. However, the mechanism underlying this phenomenon remains uncharacterized. To address this question, we induced the most common mutation identified in JMML (Ptpn11E76K) specifically in the myeloid lineage with hematopoietic stem cells (HSCs) spared. These mice uniformly developed a JMML-like MPN. Importantly, HSCs in the same bone marrow (BM) microenvironment were aberrantly activated and differentiated at the expense of self-renewal. As a result, HSCs lost quiescence and became exhausted. A similar result was observed in wild-type (WT) donor HSCs when co-transplanted with Ptpn11E76K/+ BM cells into WT mice. Co-culture testing demonstrated that JMML/MPN cells robustly accelerated differentiation in mouse and human normal hematopoietic stem/progenitor cells. Cytokine profiling revealed that Ptpn11E76K/+ MPN cells produced excessive IL-1β, but not IL-6, T NF-α, IFN-γ, IL-1α, or other inflammatory cytokines. Depletion of the IL-1β receptor effectively restored HSC quiescence, normalized their pool size, and rescued them from exhaustion in Ptpn11E76K/+/IL-1R−/− double mutant mice. These findings suggest IL-1β signaling as a potential therapeutic target for preserving normal hematopoietic development in JMML.

Assessing the Association of Mitochondrial Function and Inflammasome Activation in Murine Macrophages Exposed to Select Mitotoxic Tri-Organotin Compounds.

Background:Mitochondrial function is implicated as a target of environmental toxicants and found in disease or injury models, contributing to acute and chronic inflammation. One mechanism by which mitochondrial damage can propagate inflammation is via activation of the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family, pyrin domain-containing receptor (NLRP)3 inflammasome, a protein complex that processes mature interleukin . plays an important role in the innate immune response and dysregulation is associated with autoinflammatory disorders.Objective:The objective was to evaluate whether mitochondrial toxicants recruit inflammasome activation and processing.Method:Murine macrophages (RAW 264.7) exposed to tri-organotins (triethyltin bromide (TETBr), trimethyltin hydroxide (TMTOH), triphenyltin hydroxide (TPTOH), bis(tributyltin)oxide) [Bis(TBT)Ox] were examined for pro-inflammatory cytokine induction. TMTOH and TETBr were examined in RAW 264.7 and bone marrow-derived macrophages for mitochondrial bioenergetics, reactive oxygen species (ROS) production, and inflammasome activation via visualization of aggregate formation, caspase-1 flow cytometry, enzyme-linked immunosorbent assay and Western blots, and microRNA (miRNA) and mRNA arrays.Results:TETBr and TMTOH induced inflammasome aggregate formation and release in lipopolysaccharide (LPS)-primed macrophages. Mitochondrial bioenergetics and mitochondrial ROS were suppressed. Il1a and Il1b induction with LPS or challenge was diminished. Differential miRNA and mRNA profiles were observed. Lower miR-151-3p targeted cyclic adenosine monophosphate (cAMP)-mediated and AMP-activated protein kinase signaling pathways; higher miR-6909-5p, miR-7044-5p, and miR-7686-5p targeted Wnt beta-catenin signaling, retinoic acid receptor activation, apoptosis, signal transducer and activator of transcription 3, IL-22, IL-12, and IL-10 signaling. Functional enrichment analysis identified apoptosis and cell survival canonical pathways.Conclusion:Select mitotoxic tri-organotins disrupted murine macrophage transcriptional response to LPS, yet triggered inflammasome activation. The differential response pattern suggested unique functional changes in the inflammatory response that may translate to suppressed host defense or prolong inflammation. We posit a framework to examine immune cell effects of environmental mitotoxic compounds for adverse health outcomes. https://doi.org/10.1289/EHP8314

The deubiquitinase STAMBP modulates cytokine secretion through the NLRP3 inflammasome

The NACHT, LRR and PYD domains-containing protein 3 (NLRP3) inflammasome is a multimeric, cytoplasmic, protein complex that regulates maturation and secretion of interleukin (IL)-1β, a potent pro-inflammatory cytokine. Critical to host defense against pathogens, IL-1β amplifies early innate immune responses by activating transcription of numerous other cytokines and chemokines. Excessive IL-1β is associated with poor outcomes in inflammatory illnesses, such as sepsis and the acute respiratory distress syndrome (ARDS). Tight regulation of this signaling axis is vital, but little is known about mechanisms to limit excessive inflammasome activity. Here we identify the deubiquitinase STAM-binding protein (STAMBP) as a negative regulator of the NLRP3 inflammasome. In monocytes, knockout of STAMBP by CRISPR/Cas9 gene editing increased expression of numerous cytokines and chemokines in response to Toll-like receptor (TLR) agonists or bacterial lipopolysaccharide (LPS). This exaggerated inflammatory response was dependent on IL-1β signaling, and STAMBP knockout directly increased release of IL-1β with TLR ligation. While STAMBP does not modulate NLRP3 protein abundance, cellular depletion of the deubiquitinase increased NLRP3 K63 chain polyubiquitination resulting in increased NLRP3 inflammasome activation. These findings describe a unique mechanism of non-degradative ubiquitination of NLRP3 by STAMBP to limit excessive inflammasome activation and to reduce injurious IL-1β signaling.

Effect of anti-interleukin-1 treatment on quality of life in children with colchicine-resistant familial Mediterranean fever: A single-center experience.

The aim of this study is to evaluate the clinical parameters, acute-phase reactants, side effects, genetic mutations among colchicine-resistant Familial Mediterranean fever (FMF) patients who received anti-interleukin-1 (anti-IL-1) treatment. We also evaluate the quality of life and school attendance among colchicine-resistant FMF patients, in relation to treatment with anti-IL-1. Familial Mediterranean fever is the most common inherited autoinflammatory disorder. Although the main treatment of FMF is colchicine, a small group of patients are resistant to colchicine treatment. Anti-IL-1 treatment is promising in colchicine-resistant patients due to excessive IL-1β production in pathogenesis. The aim of this study is to evaluate the quality of life and school attendance rates among colchicine-resistant FMF patients after anti-IL-1 treatment. This is a single center retrospective study of 25 pediatric colchicine-resistant FMF patients treated with anti-IL-1 treatment. Autoinflammatory Disease Activity Index (AIDAI) was used for disease activity assessment. School attendance rates were evaluated before and after treatment. There were 25 patients with FMF (11M/14 F) who were treated with anakinra or canakinumab for various indications (colchicine-resistant recurrent febrile attacks in 20, colchicine-related side effects in 2, subclinical inflammation in 3 patients). Only 3 patients developed side effects with anakinra (2 headache, 1 urticarial rash). There was a significant decrease in the frequency of attacks, acute-phase reactants (erythrocyte sedimentation rate and C-reactive protein), AIDAI and physician's and patient's global assessment scores and improvement in school attendance rates. At the last follow-up, all patients were in remission, and only 3 had subclinical inflammation. Anti-IL-1 treatment is quite effective in children with colchicine-resistant FMF patients, proven with improved AIDAI scores and school attendance rates. In the long term by lowering disease activation even development of amyloidosis may be prevented.

Should COVID-19 take advice from rheumatologists?

Should COVID-19 take advice from rheumatologists?

Autoinflammatory Eye Disease Due to NLRP3 Inflammasome-Associated Mutations and Excessive IL-1β Responses may be Driven by Ocular Exposure to Commensals

Abstract In previous studies we have shown that the healthy murine ocular surface is colonized by a commensal, Corynebacterium mastitidis, that elicits IL-17 from γδ T cells and promotes local host defense. Based on that, we hypothesized that ocular inflammation in patients with NLRP3-associated mutations, including those with Cryopyrin Associated Periodic Syndrome (CAPS), may be triggered by an overactive response to their own eye surface commensals. We found that, unlike wild type mice, mice with a CAPS mutant NLRP3 gene and increased IL-1β and IL-17 responses, develop conjunctival neutrophilia and ocular inflammation following ocular exposure to C. mast. Single cell transcriptomics confirmed that conjunctival γδ T cells were the major source of IL-17 and identified increased amounts of ccr2 and s100a8 mRNA, accounting for the neutrophil infiltration. In parallel studies of patients with inflammasome-associated mutations (NLRP3 or CARD8 mutations) we found that patient PBMCs cultured with C. mast produced increased amounts of IL-17A compared to healthy controls (C. mast. status of subjects: unknown). Patient immune cells (conjunctival and PBMC) showed upregulation of RORC, BATF and STAT3 as well as interferon-related genes (IRF1, STAT1). However, unlike in mice, IL-17-related genes appeared to be more upregulated in αβ than in γδ T cells, suggesting that in patients this response may be mediated by other cells, and/or that other commensals than in mice may be the stimulus. Thus, commensals can elicit an exaggerated immune response in humans and mice with NLRP3-related autoinflammatory disease. If indeed the conjunctivitis in CAPS patients reflects a response to their own commensals, adjunct antimicrobial therapy may be considered.

NLRP3炎性小体与皮肤病

NOD-like receptor protein 3 (NLRP3) inflammasomes play an important role in innate immunity. It can induce the maturation and release of cytokines interleukin (IL) -1β and IL-18 by activating caspase-1, and participate in a variety of host immunoinflammatory responses. Once the regulation of NLRP3 inflammasomes is unbalanced, excessive IL-1β and IL-18 may be produced, triggering a series of inflammatory diseases. NLRP3 inflammasome activation plays important roles in skin diseases such as acne, psoriasis, pyoderma gangrenosum, polymyositis/dermatomyositis and bullous pemphigoid. This review summarizes research progress in NLRP3 inflammasomes in skin diseases. Key words: Inflammasomes; Interleukin-1beta; Interleukin-18; Skin diseases; NLRP3