Role of IL-33 in inflammation and disease

Increased Cytokine Levels in Seronegative Myositis: Potential Th17 Immune Response Implications

Th17 cells are known for producing IL-17 and their role in the pathogenesis of various autoimmune diseases, including myositis. Likewise, the participation of the IL-23/IL-17 pathway in autoimmunity has been confirmed. In this study, we aimed to evaluate the behavior of cytokines in myositis, focusing on the autoantibodies profile and the myositis core set measures. Twenty-five myositis patients were enrolled in this cross-sectional study. An expert rheumatologist evaluated the myositis core set measures. Serum levels of cytokines and chemokines were quantified using the LEGENDplex Multi-Analyte Flow Assay Kit from BioLegend. The autoantibodies detection was carried out using the line-blot assay kit Euroline: Autoimmune Inflammatory Myopathies from EUROIMMUN. We found higher serum levels of IL-33, CXCL8, IL-6, IL-23, and IL-12p70 in seronegative patients. A multiple linear regression analysis revealed that MYOACT scores could be predicted by the increment of IL-23 and the decrement of CCL2, IL-10, and CXCL8 serum levels. These findings suggest that the immune response in seronegative myositis patients exhibits an IL-23-driven Th17 immune response. The relevance of this discovery lies in its potential therapeutic implications. Insights into the IL-23-driven Th17 immune response in seronegative patients highlight the potential for targeted therapies aimed at modulating Th17 activity.

Cytokine landscape in hospitalized children with multisystem inflammatory syndrome

The etiology of multisystem inflammatory syndrome in children (MIS-C), frequently observed following COVID-19 infection, remains elusive. This study unveils insights derived from cytokine analysis in the sera of MIS-C patients, both before and after the administration of intravenous immunoglobulin (IVIG) and glucocorticosteroids (GCS). In this study, we employed a comprehensive 45-cytokine profile encompassing a spectrum of widely recognized proinflammatory and antiinflammatory cytokines, as well as growth factors, along with other soluble mediators. The analysis delineates three principal cytokine-concentration patterns evident in the patients' sera. Pattern no.1 predominantly features proinflammatory cytokines (IL-6, IL-15, IL-1ra, granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor α (TNFα), C-X-C motif chemokine ligand 10 (CXCL10/ IP-10), and IL-10) exhibiting elevated concentrations upon admission, swiftly normalizing post-hospital treatment. Pattern no. 2 includes cytokines (IL-17 A, IL-33, IFNγ, vascular endothelial growth factor (VEGF), and programmed death ligand (PD-L1)) with moderately elevated levels at admission, persisting over 7-10 days of hospitalization despite the treatment. Pattern no. 3 comprises cytokines which concentrations escalated after 7-10 days of hospitalization and therapy, including IL-1α, IL-1β, IL-2, IL-13, platelet-derived growth factor AA/BB (PDGF AA/BB). The observed in cytokine profile of MIS-C patients showed a transition from acute inflammation to sustaining inflammation which turned into induction of humoral memory mechanisms and various defense mechanisms, contributing to recovery.

IL-33 in Ischemic Stroke: Brain vs. Periphery

Cerebrovascular disease is the second-leading cause of death and disability worldwide, with stroke being the most common cause. In ischemic stroke, several processes combine to produce immunosuppression, leaving the post-stroke body susceptible to infection, which in turn affects neuroinflammation. Interleukin-33 (IL-33), a member of the interleukin-1 family (IL-1), functions as a modulator of immune responses and inflammation, playing a crucial role in the establishment of immunologic responses. IL-33 has been shown to have a protective effect on brain injury and represents a potential target by modulating inflammatory cytokines and stimulating immune regulatory cells. With an emphasis on preclinical and clinical studies, this review covers the impact of IL-33 on immune system mechanisms following ischemic stroke.

A comprehensive review of Sjögren's syndrome: Classification criteria, risk factors, and signaling pathways

Sjögren's syndrome (SS) is a chronic autoimmune disease that affects the exocrine glands and may lead to a range of systemic symptoms that impact various organs. Both innate and adaptive immune pathways might trigger the disease. Studying the signaling pathways underlying SS is crucial for enhancing diagnostic and therapeutic effectiveness. SS poses an ongoing challenge for medical professionals owing to the limited therapeutic options available. This review offers a comprehensive understanding of the intricate nature of SS, encompassing disease classification criteria, risk factors, and signaling pathways in immunity and inflammation. The advancements summarized herein have the potential to spark new avenues of research into SS.

The intriguing role of IL33/ST2 axis signaling in oral diseases - A systematic review

PURPOSE

Oral diseases act as a silent epidemic, and the pathogenetic role of interleukin-33/suppression of tumorigenicity-2 axis (IL-33/ST2) remains unclear due to a lack of literature. This review has attempted to highlight the importance of this axis in oral diseases, which may be helpful in developing therapeutic modalities required to halt disease progression.

MATERIALS AND METHODS

A thorough search was conducted using various databases. Original research articles that assessed both IL-33 and ST2 levels in oral diseases using different techniques were included in the review. The risk of bias for each study was analyzed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool and Review Manager 5.4 was used to output the results.

RESULTS

In the qualitative data synthesis we included 13 published articles. The most commonly used method was serum estimation, while methods with optimistic results were saliva, real-time quantitative polymerase chain reaction and immunohistochemistry. The predominant mechanism of action was nuclear factor kappa B signaling and type 2 immune response. However, salivary gland epithelial cell activation, activation of mast cells, type 1 immune response, and upregulated angiogenesis are crucial in mediating IL-33/ST2 signaling in oral diseases.

CONCLUSIONS

Accumulating evidence demonstrates that the IL-33/ST2 axis is a fundamental pathogenetic mechanism of oral diseases of inflammatory, autoimmune, or neoplastic origin.

Chemokine Receptor CCR2 Is Protective toward Outer Hair Cells in Chronic Suppurative Otitis Media

Chronic suppurative otitis media (CSOM) is a neglected disease that afflicts 330 million people worldwide and is the most common cause of permanent hearing loss among children in the developing world. Previously, we discovered that outer hair cell (OHC) loss occurred in the basal turn of the cochlea and that macrophages are the major immune cells associated with OHC loss in CSOM. Macrophage-associated cytokines are upregulated. Specifically, CCL-2, an important member of the MCP family, is elevated over time following middle ear infection. CCR2 is a common receptor of the MCP family and the unique receptor of CCL2. CCR2 knockout mice (CCR2-/-) have been used extensively in studies of monocyte activation in neurodegenerative diseases. In the present study, we investigated the effect of CCR2 deletion on the cochlear immune response and OHC survival in CSOM. The OHC survival rate was 84 ± 12.5% in the basal turn of CCR2+/+ CSOM cochleae, compared with was 63 ± 19.9% in the basal turn of CCR2-/- CSOM cochleae (p ≤ 0.05). Macrophage numbers were significantly reduced in CCR2-/- CSOM cochleae compared with CCR2+/+ CSOM cochleae (p ≤ 0.001). In addition, CCL7 was upregulated, whereas IL-33 was downregulated, in CCR2-/- CSOM cochleae. Finally, the permeability of the blood-labyrinth barrier in the stria vascularis remained unchanged in CCR2-/- CSOM compared with CCR2+/+ CSOM. Taken together, the data suggest that CCR2 plays a protective role through cochlear macrophages in the CSOM cochlea.

Lipidomics reveals the serum profiles of pediatric allergic rhinitis and its severity

Allergic rhinitis (AR) is a prevalent upper airway chronic inflammatory disease in children worldwide. The role of bioactive lipids in the regulation of AR has been recognized, but the underlying serum lipidomic basis of its pathology remains unclear. We utilized ultra-performance liquid chromatography (UPLC)-Q-Exactive Orbitrap/mass spectrometry (MS) to investigate the serum lipidomic profiles of children with AR. The lipidomic analysis identified 42 lipids that were differentially expressed (p < 0.05, fold change > 2) between the AR (n = 75) and normal control groups (n = 44). Specifically, the serum levels of diacylglycerol (DG), triacylglycerol (TG), fatty acid (FA), lysophosphatidylcholine (LPC), lysophosphatidylethanolamine, phosphatidyl-ethanolamine, and cardiolipins were significantly higher in the AR group. The diagnostic potential of the identified lipids was further evaluated using receiver operating characteristic curve analysis. The analysis revealed that five lipids, including FA 30:7, LPC O-18:1, LPC 18:0, LPC 16:0, and DG 34:0, had area under the curve values greater than 0.9 (p < 0.05). Furthermore, serum levels of IgE and IL-33, markers of AR severity, were found to have a significant positive correlation (p < 0.05) with DGs, LPCs, TGs, and FAs in AR patients. This study revealed the lipid disorders associated with AR and its severity, providing new insights into the pathological process of AR.

Sex differences and immune correlates of Long COVID development, persistence, and resolution

Sex differences have been observed in acute COVID-19 and Long COVID (LC) outcomes, with greater disease severity and mortality during acute infection in males and a greater proportion of females developing LC. We hypothesized that sex-specific immune dysregulation contributes to the pathogenesis of LC. To investigate the immunologic underpinnings of LC development and persistence, we used single-cell transcriptomics, single-cell proteomics, and plasma proteomics on blood samples obtained during acute SARS-CoV-2 infection and at 3 and 12 months post-infection in a cohort of 45 patients who either developed LC or recovered. Several sex-specific immune pathways were associated with LC. Specifically, males who would develop LC at 3 months had widespread increases in TGF-β signaling during acute infection in proliferating NK cells. Females who would develop LC demonstrated increased expression of XIST, an RNA gene implicated in autoimmunity, and increased IL1 signaling in monocytes at 12 months post infection. Several immune features of LC were also conserved across sexes. Both males and females with LC had reduced co-stimulatory signaling from monocytes and broad upregulation of NF-κB transcription factors. In both sexes, those with persistent LC demonstrated increased LAG3, a marker of T cell exhaustion, reduced ETS1 transcription factor expression across lymphocyte subsets, and elevated intracellular IL-4 levels in T cell subsets, suggesting that ETS1 alterations may drive an aberrantly elevated Th2-like response in LC. Altogether, this study describes multiple innate and adaptive immune correlates of LC, some of which differ by sex, and offers insights toward the pursuit of tailored therapeutics.

IL-33 and IL-33-derived DC-based tumor immunotherapy

Interleukin-33 (IL-33), a member of the IL-1 family, is a cytokine released in response to tissue damage and is recognized as an alarmin. The multifaceted roles of IL-33 in tumor progression have sparked controversy within the scientific community. However, most findings generally indicate that endogenous IL-33 has a protumor effect, while exogenous IL-33 often has an antitumor effect in most cases. This review covers the general characteristics of IL-33 and its effects on tumor growth, with detailed information on the immunological mechanisms associated with dendritic cells (DCs). Notably, DCs possess the capability to uptake, process, and present antigens to CD8+ T cells, positioning them as professional antigen-presenting cells. Recent findings from our research highlight the direct association between the tumor-suppressive effects of exogenous IL-33 and a novel subset of highly immunogenic cDC1s. Exogenous IL-33 induces the development of these highly immunogenic cDC1s through the activation of other ST2+ immune cells both in vivo and in vitro. Recognizing the pivotal role of the immunogenicity of DC vaccines in DC-based tumor immunotherapy, we propose compelling methods to enhance this immunogenicity through the addition of IL-33 and the promotion of highly immunogenic DC generation.

Leishmania exploits host cAMP/EPAC/calcineurin signaling to induce an IL-33-mediated anti-inflammatory environment for the establishment of infection

Host anti-inflammatory responses are critical for the progression of visceral leishmaniasis, and the pleiotropic cytokine interleukin (IL)-33 was found to be upregulated in infection. Here, we documented that IL-33 induction is a consequence of elevated cAMP-mediated exchange protein activated by cAMP (EPAC)/calcineurin-dependent signaling and essential for the sustenance of infection. Leishmania donovani-infected macrophages showed upregulation of IL-33 and its neutralization resulted in decreased parasite survival and increased inflammatory responses. Infection-induced cAMP was involved in IL-33 production and of its downstream effectors PKA and EPAC, only the latter was responsible for elevated IL-33 level. EPAC initiated Rap-dependent phospholipase C activation, which triggered the release of intracellular calcium followed by calcium/calmodulin complex formation. Screening of calmodulin-dependent enzymes affirmed involvement of the phosphatase calcineurin in cAMP/EPAC/calcium/calmodulin signaling-induced IL-33 production and parasite survival. Activated calcineurin ensured nuclear localization of the transcription factors, nuclear factor of activated T cell 1 and hypoxia-inducible factor 1 alpha required for IL-33 transcription, and we further confirmed this by chromatin immunoprecipitation assay. Administering specific inhibitors of nuclear factor of activated T cell 1 and hypoxia-inducible factor 1 alpha in BALB/c mouse model of visceral leishmaniasis decreased liver and spleen parasite burden along with reduction in IL-33 level. Splenocyte supernatants of inhibitor-treated infected mice further documented an increase in tumor necrosis factor alpha and IL-12 level with simultaneous decrease of IL-10, thereby indicating an overall disease-escalating effect of IL-33. Thus, this study demonstrates that cAMP/EPAC/calcineurin signaling is crucial for the activation of IL-33 and in effect creates anti-inflammatory responses, essential for infection.

Diet-induced obesity affects influenza disease severity and transmission dynamics in ferrets

Obesity, and the associated metabolic syndrome, is a risk factor for increased disease severity with a variety of infectious agents, including influenza virus. Yet, the mechanisms are only partially understood. As the number of people, particularly children, living with obesity continues to rise, it is critical to understand the role of host status on disease pathogenesis. In these studies, we use a diet-induced obese ferret model and tools to demonstrate that, like humans, obesity resulted in notable changes to the lung microenvironment, leading to increased clinical disease and viral spread to the lower respiratory tract. The decreased antiviral responses also resulted in obese animals shedding higher infectious virus for a longer period, making them more likely to transmit to contacts. These data suggest that the obese ferret model may be crucial to understanding obesity's impact on influenza disease severity and community transmission and a key tool for therapeutic and intervention development for this high-risk population.

ST2 levels and neurodegenerative diseases: is this a significant relation?

Interleukin-33 (IL-33), belonging to the interleukin-1 cytokine family, has a decoy receptor soluble ST2 (sST2). IL-33 is found in oligodendrocytes and astrocytes and is involved in central nervous system healing and repair, whereas ST2 is found in microglia and astrocytes. Some studies have found a link between changes in the IL-33/ST2 pathway and neurodegenerative disorders. This review article investigates the relationship between the interleukin-33 (IL-33)/ST2 pathway and neurodegenerative disorders. It was discovered that soluble st2 levels were increased. Furthermore, IL-33 levels were found to be lower in many neurodegenerative diseases such as Alzheimer's and amyotrophic lateral sclerosis (ALS). The association with other disorders, such as ankylosing spondylitis, multiple sclerosis, and systemic lupus erythematosus (SLE), was also observed. Various studies suggest that ST2/IL-33 signalling may be pivotal in the disease modulation of neurodegenerative disorders. The serum sST2 level test can be useful in determining the inflammatory status and severity of illness in many neurodegenerative disorders. In this review, we will discuss recent findings concerning the interleukin-33 (IL-33)/ST2 pathway and its role in the diagnosis and treatment of diseases with neurodegeneration.

The Role of Cytokines in Cutaneous T Cell Lymphoma: A Focus on the State of the Art and Possible Therapeutic Targets

Cutaneous T cell lymphomas (CTCLs), encompassing mycosis fungoides (MF) and Sézary syndrome (SS), present a complex landscape influenced by cytokines and cellular responses. In this work, the intricate relationship between these inflammatory proteins and disease pathogenesis is examined, focusing on what is known at the clinical and therapeutic levels regarding the most well-known inflammatory mediators. An in-depth look is given to their possible alterations caused by novel immunomodulatory drugs and how they may alter disease progression. From this narrative review of the actual scientific landscape, Interferon-gamma (IFN-γ) emerges as a central player, demonstrating a dual role in both promoting and inhibiting cancer immunity, but the work navigates through all the major interleukins known in inflammatory environments. Immunotherapeutic perspectives are elucidated, highlighting the crucial role of the cutaneous microenvironment in shaping dysfunctional cell trafficking, antitumor immunity, and angiogenesis in MF, showcasing advancements in understanding and targeting the immune phenotype in CTCL. In summary, this manuscript aims to comprehensively explore the multifaceted aspects of CTCL, from the immunopathogenesis and cytokine dynamics centred around TNF-α and IFN-γ to evolving therapeutic modalities. Including all the major known and studied cytokines in this analysis broadens our understanding of the intricate interplay influencing CTCL, paving the way for improved management of this complex lymphoma.

The Role of Selected Interleukins in the Development and Progression of Multiple Sclerosis-A Systematic Review

Multiple sclerosis is a disabling inflammatory disorder of the central nervous system characterized by demyelination and neurodegeneration. Given that multiple sclerosis remains an incurable disease, the management of MS predominantly focuses on reducing relapses and decelerating the progression of both physical and cognitive decline. The continuous autoimmune process modulated by cytokines seems to be a vital contributing factor to the development and relapse of multiple sclerosis. This review sought to summarize the role of selected interleukins in the pathogenesis and advancement of MS. Patients with MS in the active disease phase seem to exhibit an increased serum level of IL-2, IL-4, IL-6, IL-13, IL-17, IL-21, IL-22 and IL-33 compared to healthy controls and patients in remission, while IL-10 appears to have a beneficial impact in preventing the progression of the disease. Despite being usually associated with proinflammatory activity, several studies have additionally recognized a neuroprotective role of IL-13, IL-22 and IL-33. Moreover, selected gene polymorphisms of IL-2R, IL-4, IL-6, IL-13 and IL-22 were identified as a possible risk factor related to MS development. Treatment strategies of multiple sclerosis that either target or utilize these cytokines seem rather promising, but more comprehensive research is necessary to gain a clearer understanding of how these cytokines precisely affect MS development and progression.

The dichotomic role of single cytokines: Fine-tuning immune responses

Cytokines are known for their pleiotropic effects. They can be classified by their function as pro-inflammatory, such as tumor necrosis factor (TNF), interleukin (IL) 1 and IL-12, or anti-inflammatory, like IL-10, IL-35 and transforming growth factor β (TGF-β). Though this type of classification is an important simplification for the understanding of the general cytokine's role, it can be misleading. Here, we discuss recent studies that show a dichotomic role of the so-called pro and anti-inflammatory cytokines, highlighting that their function can be dependent on the microenvironment and their concentrations. Furthermore, we discuss how the back-and-forth interplay between cytokines and immunometabolism can influence the dichotomic role of inflammatory responses as an important target to complement cytokine-based therapies.

Immunology of amyotrophic lateral sclerosis - role of the innate and adaptive immunity

This review aims to summarize the latest evidence about the role of innate and adaptive immunity in Amyotrophic Lateral Sclerosis (ALS). ALS is a devastating neurodegenerative disease affecting upper and lower motor neurons, which involves essential cells of the immune system that play a basic role in innate or adaptive immunity, that can be neurotoxic or neuroprotective for neurons. However, distinguishing between the sole neurotoxic or neuroprotective function of certain cells such as astrocytes can be challenging due to intricate nature of these cells, the complexity of the microenvironment and the contextual factors. In this review, in regard to innate immunity we focus on the involvement of monocytes/macrophages, microglia, the complement, NK cells, neutrophils, mast cells, and astrocytes, while regarding adaptive immunity, in addition to humoral immunity the most important features and roles of T and B cells are highlighted, specifically different subsets of CD4+ as well as CD8+ T cells. The role of autoantibodies and cytokines is also discussed in distinct sections of this review.

Interleukin-33 Expression on Treatment Outcomes and Prognosis in Brazilian Breast Cancer Patients Undergoing Neoadjuvant Chemotherapy

Interleukin-33 (IL-33), a member of the interleukin-1(IL-1) family of cytokines, remains poorly understood in the context of human breast cancer and its impact on treatment outcomes. This study aimed to elucidate IL-33 expression patterns within tumor samples from a cohort of Brazilian female breast cancer patients undergoing neoadjuvant chemotherapy while exploring its correlation with clinicopathological markers. In total, 68 samples were meticulously evaluated, with IL-33 expression quantified through a quantitative polymerase chain reaction. The findings revealed a substantial upregulation of IL-33 expression in breast cancer patient samples, specifically within the Triple-negative and Luminal A and B subtypes, when compared to controls (healthy breast tissues). Notably, the Luminal B subtype displayed a marked elevation in IL-33 expression relative to the Luminal A subtype (p < 0.05). Moreover, a progressive surge in IL-33 expression was discerned among Luminal subtype patients with TNM 4 staging criteria, further underscoring its significance (p < 0.005). Furthermore, chemotherapy-naïve patients of Luminal A and B subtypes exhibited heightened IL-33 expression (p < 0.05). Collectively, our findings propose that chemotherapy could potentially mitigate tumor aggressiveness by suppressing IL-33 expression in breast cancer, thus warranting consideration as a prognostic marker for gauging chemotherapy response and predicting disease progression in Luminal subtype patients. This study not only sheds light on the intricate roles of IL-33 in breast cancer but also offers valuable insights for future IL-33-related research endeavors within this context.

The Role and Therapeutic Implications of Inflammation in the Pathogenesis of Brain Arteriovenous Malformations

Brain arteriovenous malformations (bAVMs) are focal vascular lesions composed of abnormal vascular channels without an intervening capillary network. As a result, high-pressure arterial blood shunts directly into the venous outflow system. These high-flow, low-resistance shunts are composed of dilated, tortuous, and fragile vessels, which are prone to rupture. BAVMs are a leading cause of hemorrhagic stroke in children and young adults. Current treatments for bAVMs are limited to surgery, embolization, and radiosurgery, although even these options are not viable for ~20% of AVM patients due to excessive risk. Critically, inflammation has been suggested to contribute to lesion progression. Here we summarize the current literature discussing the role of the immune system in bAVM pathogenesis and lesion progression, as well as the potential for targeting inflammation to prevent bAVM rupture and intracranial hemorrhage. We conclude by proposing that a dysfunctional endothelium, which harbors the somatic mutations that have been shown to give rise to sporadic bAVMs, may drive disease development and progression by altering the immune status of the brain.

Diet-induced obesity impacts influenza disease severity and transmission dynamics in ferrets

Obesity, and the associated metabolic syndrome, is a risk factor for increased disease severity with a variety of infectious agents, including influenza virus. Yet the mechanisms are only partially understood. As the number of people, particularly children, living with obesity continues to rise, it is critical to understand the role of host status on disease pathogenesis. In these studies, we use a novel diet-induced obese ferret model and new tools to demonstrate that like humans, obesity resulted in significant changes to the lung microenvironment leading to increased clinical disease and viral spread to the lower respiratory tract. The decreased antiviral responses also resulted in obese animals shedding higher infectious virus for longer making them more likely to transmit to contacts. These data suggest the obese ferret model may be crucial to understanding obesity's impact on influenza disease severity and community transmission, and a key tool for therapeutic and intervention development for this high-risk population.

Teaser

A new ferret model and tools to explore obesity's impact on respiratory virus infection, susceptibility, and community transmission.

Decoding the IL-33/ST2 Axis: Its Impact on the Immune Landscape of Breast Cancer

Interleukin-33 (IL-33) has emerged as a critical cytokine in the regulation of the immune system, showing a pivotal role in the pathogenesis of various diseases including cancer. This review emphasizes the role of the IL-33/ST2 axis in breast cancer biology, its contribution to cancer progression and metastasis, its influence on the tumor microenvironment and cancer metabolism, and its potential as a therapeutic target. The IL-33/ST2 axis has been shown to have extensive pro-tumorigenic features in breast cancer, starting from tumor tissue proliferation and differentiation to modulating both cancer cells and anti-tumor immune response. It has also been linked to the resistance of cancer cells to conventional therapeutics. However, the role of IL-33 in cancer therapy remains controversial due to the conflicting effects of IL-33 in tumorigenesis and anti-tumor response. The possibility of targeting the IL-33/ST2 axis in tumor immunotherapy, or as an adjuvant in immune checkpoint blockade therapy, is discussed.

Oxidised IL-33 drives COPD epithelial pathogenesis via ST2-independent RAGE/EGFR signalling complex

BACKGROUND

Epithelial damage, repair and remodelling are critical features of chronic airway diseases including chronic obstructive pulmonary disease (COPD). Interleukin (IL)-33 released from damaged airway epithelia causes inflammation via its receptor, serum stimulation-2 (ST2). Oxidation of IL-33 to a non-ST2-binding form (IL-33ox) is thought to limit its activity. We investigated whether IL-33ox has functional activities that are independent of ST2 in the airway epithelium.

METHODS

In vitro epithelial damage assays and three-dimensional, air-liquid interface (ALI) cell culture models of healthy and COPD epithelia were used to elucidate the functional role of IL-33ox. Transcriptomic changes occurring in healthy ALI cultures treated with IL-33ox and COPD ALI cultures treated with an IL-33-neutralising antibody were assessed with bulk and single-cell RNA sequencing analysis.

RESULTS

We demonstrate that IL-33ox forms a complex with receptor for advanced glycation end products (RAGE) and epidermal growth factor receptor (EGFR) expressed on airway epithelium. Activation of this alternative, ST2-independent pathway impaired epithelial wound closure and induced airway epithelial remodelling in vitro. IL-33ox increased the proportion of mucus-producing cells and reduced epithelial defence functions, mimicking pathogenic traits of COPD. Neutralisation of the IL-33ox pathway reversed these deleterious traits in COPD epithelia. Gene signatures defining the pathogenic effects of IL-33ox were enriched in airway epithelia from patients with severe COPD.

CONCLUSIONS

Our study reveals for the first time that IL-33, RAGE and EGFR act together in an ST2-independent pathway in the airway epithelium and govern abnormal epithelial remodelling and muco-obstructive features in COPD.

Inhibitory Effects of Simvastatin on IL-33-Induced MCP-1 via the Suppression of the JNK Pathway in Human Vascular Endothelial Cells

An alarmin, interleukin (IL)-33 is a danger signal that causes inflammation, inducing chemotactic proteins such as monocyte chemoattractant protein (MCP)-1 in various cells. As statins have pleiotropic actions including anti-inflammatory properties, we investigated the effects of simvastatin on IL-33-induced MCP-1 expression in human umbilical vein endothelial cells (HUVECs). HUVECs were stimulated with IL-33 in the presence or absence of simvastatin. Gene expression and protein secretion of MCP-1, phosphorylation of mitogen-activated protein kinase (MAPK), nuclear translocation of phosphorylated c-Jun, and human monocyte migration were investigated. Immunocytochemical staining and Western immunoblot analysis revealed that IL-33 augmented MCP-1 protein expression in HUVECs. Real-time reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) showed that IL-33 significantly increased MCP-1 mRNA and protein secretion, which were suppressed by c-jun N-terminal kinase (JNK) inhibitor SP600125 and p38 MAPK inhibitor SB203580. Simvastatin inhibited IL-33-induced MCP-1 mRNA, protein secretion, phosphorylation of JNK and c-Jun. Additionally, the IL-33-induced nuclear translocation of phosphorylated c-Jun and THP-1 monocyte migration were also blocked by simvastatin. This study demonstrated that IL-33 induces MCP-1 expression via the JNK and p38 MAPK pathways in HUVECs, and that simvastatin inhibits MCP-1 production by selectively suppressing JNK. Simvastatin may inhibit the progression of IL-33-induced inflammation via suppressing JNK to prevent MCP-1 production.

Endothelial Cell Response in Kawasaki Disease and Multisystem Inflammatory Syndrome in Children

Although Kawasaki disease (KD) and multisystem inflammatory syndrome in children (MIS-C) share some clinical manifestations, their cardiovascular outcomes are different, and this may be reflected at the level of the endothelial cell (EC). We performed RNA-seq on cultured ECs incubated with pre-treatment sera from KD (n = 5), MIS-C (n = 7), and healthy controls (n = 3). We conducted a weighted gene co-expression network analysis (WGCNA) using 935 transcripts differentially expressed between MIS-C and KD using relaxed filtering (unadjusted p < 0.05, >1.1-fold difference). We found seven gene modules in MIS-C, annotated as an increased TNFα/NFκB pathway, decreased EC homeostasis, anti-inflammation and immune response, translation, and glucocorticoid responsive genes and endothelial-mesenchymal transition (EndoMT). To further understand the difference in the EC response between MIS-C and KD, stringent filtering was applied to identify 41 differentially expressed genes (DEGs) between MIS-C and KD (adjusted p < 0.05, >2-fold-difference). Again, in MIS-C, NFκB pathway genes, including nine pro-survival genes, were upregulated. The expression levels were higher in the genes influencing autophagy (UBD, EBI3, and SQSTM1). Other DEGs also supported the finding by WGCNA. Compared to KD, ECs in MIS-C had increased pro-survival transcripts but reduced transcripts related to EndoMT and EC homeostasis. These differences in the EC response may influence the different cardiovascular outcomes in these two diseases.

Long-term in vivo vitamin D3 supplementation modulates bovine IL-1 and chemokine responses

Vitamin D deficiency at birth, followed by prolonged insufficiency in early life may predispose bovine calves to infection and disease. However, the effects of vitamin D levels on innate immunity are unclear due to the lack of long-term supplementation trials in vivo and reliable approaches for reproducibly assessing immune function. Here, a standardized whole blood immunophenotyping assay was used to compare innate immune responses to infection relevant ligands (LPS, Pam3CSK4 and R848) between Holstein-Friesian calves supplemented with vitamin D (n = 12) from birth until 7 months of age and control calves (n = 10) raised on an industry standard diet. Transcriptomic analysis in unstimulated whole blood cells revealed increased expression of type I interferons and chemokines in vitamin D supplemented calves, while IL-1 and inflammasome gene expression was decreased. In response to stimulation with the bacterial ligand LPS, supplemented calves had significantly increased expression of CASP1, CX3CR1, CAT, whereas STAT1 was decreased. Stimulation with the bacterial ligand Pam3CSK4 revealed increased expression of IL1A, IL1B and CAT genes; and decreased C5AR1 expression. In response to the viral ligand R848, STAT1 and S100A8 expression was significantly decreased. An increased IL-1 and inflammasome gene expression signature in vitamin D supplemented calves in response to LPS and Pam3CSK4 was also found, with ELISA confirming increased IL-1β protein production. In contrast, a decreased chemokine gene expression signature was found in response to R848 in supplemented animals, with decreased IL-8 protein expression exhibited in response to all PAMPs also found. These results demonstrated expression of several cytokine, chemokine and inflammasome genes were impacted by vitamin D supplementation in the first 7 months of life, with IL-8 expression particularly responsive to vitamin D. Overall, vitamin D supplementation induced differential innate immune responses of blood immune cells that could have important implications for disease susceptibility in cattle.

IL-33/ST2 axis of human amnion fibroblasts participates in inflammatory reactions at parturition

BACKGROUND

Inflammation of the fetal membranes is an indispensable event of labor onset at both term and preterm birth. Interleukin-33 (IL-33) is known to participate in inflammation via ST2 (suppression of tumorigenicity 2) receptor as an inflammatory cytokine. However, it remains unknown whether IL-33/ST2 axis exists in human fetal membranes to promote inflammatory reactions in parturition.

METHODS

The presence of IL-33 and ST2 and their changes at parturition were examined with transcriptomic sequencing, quantitative real-time polymerase chain reaction, Western blotting or immunohistochemistry in human amnion obtained from term and preterm birth with or without labor. Cultured primary human amnion fibroblasts were utilized to investigate the regulation and the role of IL-33/ST2 axis in the inflammation reactions. A mouse model was used to further study the role of IL-33 in parturition.

RESULTS

Although IL-33 and ST2 expression were detected in both epithelial and fibroblast cells of human amnion, they are more abundant in amnion fibroblasts. Their abundance increased significantly in the amnion at both term and preterm birth with labor. Lipopolysaccharide, serum amyloid A1 and IL-1β, the inflammatory mediators pertinent to labor onset, could all induce IL-33 expression through NF-κB activation in human amnion fibroblasts. In turn, via ST2 receptor, IL-33 induced the production of IL-1β, IL-6 and PGE2 in human amnion fibroblasts via the MAPKs-NF-κB pathway. Moreover, IL-33 administration induced preterm birth in mice.

CONCLUSION

IL-33/ST2 axis is present in human amnion fibroblasts, which is activated in both term and preterm labor. Activation of this axis leads to increased production of inflammatory factors pertinent to parturition, and results in preterm birth. Targeting the IL-33/ST2 axis may have potential value in the treatment of preterm birth.

Is There Any Difference in the In Situ Immune Response in Active Localized Cutaneous Leishmaniasis That Respond Well or Poorly to Meglumine Antimoniate Treatment or Spontaneously Heal?

Localized cutaneous leishmaniasis caused by Leishmania braziliensis can either respond well or poorly to the treatment or heal spontaneously; It seems to be dependent on the parasite and/or host factors, but the mechanisms are not fully understood. We evaluated the in situ immune response in eighty-two active lesions from fifty-eight patients prior to treatment classified as early spontaneous regression (SRL-n = 14); treatment responders (GRL-n = 20); and non-responders (before first treatment/relapse, PRL1/PRL2-n = 24 each). Immunohistochemistry was used to identify cell/functional markers which were correlated with the clinical characteristics. PRL showed significant differences in lesion number/size, clinical evolution, and positive parasitological examinations when compared with the other groups. SRL presented a more efficient immune response than GRL and PRL, with higher IFN-γ/NOS2 and a lower percentage of macrophages, neutrophils, NK, B cells, and Ki-67+ cells. Compared to SRL, PRL had fewer CD4+ Tcells and more CD163+ macrophages. PRL1 had more CD68+ macrophages and Ki-67+ cells but less IFN-γ than GRL. PRL present a less efficient immune profile, which could explain the poor treatment response, while SRL had a more balanced immune response profile for lesion healing. Altogether, these evaluations suggest a differentiated profile of the organization of the inflammatory process for lesions of different tegumentary leishmaniasis evolution.

Nicotine promotes e-cigarette vapour-induced lung inflammation and structural alterations

BACKGROUND

Electronic cigarette (e-cigarette) vapour is gaining popularity as an alternative to tobacco smoking and can induce acute lung injury. However, the specific role of nicotine in e-cigarette vapour and its long-term effects on the airways, lung parenchyma and vasculature remain unclear.

RESULTS

In vitro exposure to nicotine-containing e-cigarette vapour extract (ECVE) or to nicotine-free e-cigarette vapour extract (NF ECVE) induced changes in gene expression of epithelial cells and pulmonary arterial smooth muscle cells (PASMCs), but ECVE in particular caused functional alterations (e.g. a decrease in human and mouse PASMC proliferation by 29.3±5.3% and 44.3±8.4%, respectively). Additionally, acute inhalation of nicotine-containing e-cigarette vapour (ECV) but not nicotine-free e-cigarette vapour (NF ECV) increased pulmonary endothelial permeability in isolated lungs. Long-term in vivo exposure of mice to ECV for 8 months significantly increased the number of inflammatory cells, in particular lymphocytes, compared to control and NF ECV in the bronchoalveolar fluid (BALF) (ECV: 853.4±150.8 cells·mL-1; control: 37.0±21.1 cells·mL-1; NF ECV: 198.6±94.9 cells·mL-1) and in lung tissue (ECV: 25.7±3.3 cells·mm-3; control: 4.8±1.1 cells·mm-3; NF ECV: 14.1±2.2 cells·mm-3). BALF cytokines were predominantly increased by ECV. Moreover, ECV caused significant changes in lung structure and function (e.g. increase in airspace by 17.5±1.4% compared to control), similar to mild tobacco smoke-induced alterations, which also could be detected in the NF ECV group, albeit to a lesser degree. In contrast, the pulmonary vasculature was not significantly affected by ECV or NF ECV.

CONCLUSIONS

NF ECV components induce cell type-specific effects and mild pulmonary alterations, while inclusion of nicotine induces significant endothelial damage, inflammation and parenchymal alterations.

Modulation of IL-33/ST2 signaling as a potential new therapeutic target for cardiovascular diseases

IL-33 belongs to the IL-1 family of cytokines, which function as inducers of Th2 cytokine production by binding with ST2L and IL-1RAcP. This, in turn, activates various signaling pathways, including the mitogen-activated protein kinase (MAPK), the inhibitor of Kappa-B kinase (IKK) pathway, and the phospholipase D-sphingosine kinase pathway. IL-33 has demonstrated protective effects against various cardiovascular diseases (CVDs) by inducing Th2 cytokines and promoting alternative activating M2 polarization. However, the soluble decoy form of ST2 (sST2) mitigates the biological effects of IL-33, exacerbating CVDs. Furthermore, IL-33 also plays a significant role in the development of asthma, arthritis, atopic dermatitis, and anaphylaxis through the activation of Th2 cells and mast cells. In this review, we aim to demonstrate the protective role of IL-33 against CVDs from 2005 to the present and explore the potential of serum soluble ST2 (sST2) as a diagnostic biomarker for CVDs. Therefore, IL-33 holds promise as a potential therapeutic target for the treatment of CVDs.

Interleukin-33: Friend or Foe in Gastrointestinal Tract Cancers?

Accumulating evidence suggests that Interleukin-33 (IL-33), a member of the IL-1 family, has crucial roles in tissue homeostasis and repair, type 2 immunity, inflammation, and viral infection. IL-33 is a novel contributing factor in tumorigenesis and plays a critical role in regulating angiogenesis and cancer progression in a variety of human cancers. The partially unraveled role of IL-33/ST2 signaling in gastrointestinal tract cancers is being investigated through the analysis of patients' samples and by studies in murine and rat models. In this review, we discuss the basic biology and mechanisms of release of the IL-33 protein and its involvement in gastrointestinal cancer onset and progression.

Vascular cell-adhesion molecule 1 (VCAM-1) regulates JunB-mediated IL-8/CXCL1 expression and pathological neovascularization

Vascular adhesion molecules play an important role in various immunological disorders, particularly in cancers. However, little is known regarding the role of these adhesion molecules in proliferative retinopathies. We observed that IL-33 regulates VCAM-1 expression in human retinal endothelial cells and that genetic deletion of IL-33 reduces hypoxia-induced VCAM-1 expression and retinal neovascularization in C57BL/6 mice. We found that VCAM-1 via JunB regulates IL-8 promoter activity and expression in human retinal endothelial cells. In addition, our study outlines the regulatory role of VCAM-1-JunB-IL-8 signaling on retinal endothelial cell sprouting and angiogenesis. Our RNA sequencing results show an induced expression of CXCL1 (a murine functional homolog of IL-8) in the hypoxic retina, and intravitreal injection of VCAM-1 siRNA not only decreases hypoxia-induced VCAM-1-JunB-CXCL1 signaling but also reduces OIR-induced sprouting and retinal neovascularization. These findings suggest that VCAM-1-JunB-IL-8 signaling plays a crucial role in retinal neovascularization, and its antagonism might provide an advanced treatment option for proliferative retinopathies.

The Role of IL-33/ST2 in COPD and Its Future as an Antibody Therapy

COPD is a leading cause of mortality and morbidity worldwide and is associated with a high socioeconomic burden. Current treatment includes the use of inhaled corticosteroids and bronchodilators, which can help to improve symptoms and reduce exacerbations; however, there is no solution for restoring lung function and the emphysema caused by loss of the alveolar tissue. Moreover, exacerbations accelerate progression and challenge even more the management of COPD. Mechanisms of inflammation in COPD have been investigated over the past years, thus opening new avenues to develop novel targeted-directed therapies. Special attention has been paid to IL-33 and its receptor ST2, as they have been found to mediate immune responses and alveolar damage, and their expression is upregulated in COPD patients, which correlates with disease progression. Here we summarize the current knowledge on the IL-33/ST2 pathway and its involvement in COPD, with a special focus on developed antibodies and the ongoing clinical trials using anti-IL-33 and anti-ST2 strategies in COPD patients.

Differences and Associations of NLRP3 Inflammasome Levels with Interleukins 1α, 1β, 33 and 37 in Adults with Prediabetes and Type 2 Diabetes Mellitus

Inflammasome activation of the nucleotide-binding domain, leucine-rich-containing family, and pyrin domain-containing-3 (NLRP3) has been observed to be involved in the pathogenesis of numerous inflammatory diseases, including prediabetes (PD) and type 2 diabetes mellitus (T2DM). Varying levels of glycemia can trigger inflammasome activation; yet, limited studies have reported the associations between NLRP3 levels or other circulating interleukins (ILs) and glycemic status. This study investigated the differences and associations between serum levels of NLRP3 and IL-1α, IL-1β, IL-33 and IL-37 in Arab adults with PD and T2DM. A total of 407 Saudi adults (151 males and 256 females) (mean age = 41.4 ± 9.1 years and mean BMI = 30.7 ± 6.4 kg/m²) were included. Overnight-fasting serum samples were collected. The participants were stratified according to T2DM status. Serum levels of NLRP3 and ILs of interest were assessed using commercially available assays. In all participants, age- and BMI-adjusted circulating levels of IL-37 were significantly higher in the T2DM group (p = 0.02) than in healthy controls (HC) and the PD group. A general linear model analysis revealed that NLRP3 levels were significantly influenced by T2DM status; age; and ILs 18, 1α and 33 (p-values 0.03, 0.04, 0.005, 0.004 and 0.007, respectively). IL-1α and triglycerides significantly predicted NLRP3 levels by as much as 46% of the variance perceived (p < 0.01). In conclusion, T2DM status significantly influenced NLRP3 expression and other IL levels in varying degrees. Whether these altered levels of inflammasome markers can be favorably reversed through lifestyle interventions needs to be investigated prospectively in the same population.

Helminth-derived biomacromolecules as therapeutic agents for treating inflammatory and infectious diseases: What lessons do we get from recent findings?

Despite the tremendous progress in healthcare sectors, a number of life-threatening infectious, inflammatory, and autoimmune diseases are continuously challenging mankind throughout the globe. In this context, recent successes in utilizing helminth parasite-derived bioactive macromolecules viz. glycoproteins, enzymes, polysaccharides, lipids/lipoproteins, nucleic acids/nucleotides, and small organic molecules for treating various disorders primarily resulted from inflammation. Among the several parasites that infect humans, helminths (cestodes, nematodes, and trematodes) are known as efficient immune manipulators owing to their explicit ability to modulate and modify the innate and adaptive immune responses of humans. These molecules selectively bind to immune receptors on innate and adaptive immune cells and trigger multiple signaling pathways to elicit anti-inflammatory cytokines, expansion of alternatively activated macrophages, T-helper 2, and immunoregulatory T regulatory cell types to induce an anti-inflammatory milieu. Reduction of pro-inflammatory responses and repair of tissue damage by these anti-inflammatory mediators have been exploited for treating a number of autoimmune, allergic, and metabolic diseases. Herein, the potential and promises of different helminths/helminth-derived products as therapeutic agents in ameliorating immunopathology of different human diseases and their mechanistic insights of function at cell and molecular level alongside the molecular signaling cross-talks have been reviewed by incorporating up-to-date findings achieved in the field.

NLRP3 inhibition improves maternal hypertension, inflammation, and vascular dysfunction in response to placental ischemia

Preeclampsia (PE) is a pregnancy-specific hypertensive disorder with end-organ damage that presents after 20 wk of gestation. PE pathophysiology often includes vascular dysfunction and increased inflammation that continues to damage patient health even after PE resolves. Currently, there is no cure for PE beyond delivery of the fetal-placental unit. Previous clinical studies have identified elevated placental NLRP3 expression in patients with PE and suggest NLRP3 as a potential therapeutic target. In this study, we examined the effect of NLRP3 inhibition on PE pathophysiology in the reduced uterine perfusion pressure (RUPP) model rat using MCC950 (20 mg/kg/day) or esomeprazole (3.5 mg/kg/day). We hypothesized that increased NLRP3 in response to placental ischemia impairs anti-inflammatory IL-33 signaling to induce T-helper 17 cell (TH17) and cytolytic NK cell (cNK) activation, which is known to mediate oxidative stress and vascular dysfunction leading to maternal HTN and intrauterine growth restriction. RUPP rats had significantly higher placental NLRP3 expression, maternal blood pressure, fetal reabsorption rate, vascular resistance, oxidative stress, cNKs and TH17s, and decreased IL-33 compared with normal pregnant (NP) rats. NLRP3 inhibition, with either treatment, significantly reduced placental NLRP3 expression, maternal blood pressure, fetal reabsorption rates, vascular resistance, oxidative stress, cNK, and TH17 populations in RUPP rats. Based on our findings, NLRP3 inhibition reduces PE pathophysiology and esomeprazole may be a potential therapeutic for PE treatment.

HERVs and Cancer-A Comprehensive Review of the Relationship of Human Endogenous Retroviruses and Human Cancers

Genomic instability and genetic mutations can lead to exhibition of several cancer hallmarks in affected cells such as sustained proliferative signaling, evasion of growth suppression, activated invasion, deregulation of cellular energetics, and avoidance of immune destruction. Similar biological changes have been observed to be a result of pathogenic viruses and, in some cases, have been linked to virus-induced cancers. Human endogenous retroviruses (HERVs), once external pathogens, now occupy more than 8% of the human genome, representing the merge of genomic and external factors. In this review, we outline all reported effects of HERVs on cancer development and discuss the HERV targets most suitable for cancer treatments as well as ongoing clinical trials for HERV-targeting drugs. We reviewed all currently available reports of the effects of HERVs on human cancers including solid tumors, lymphomas, and leukemias. Our review highlights the central roles of HERV genes, such as gag, env, pol, np9, and rec in immune regulation, checkpoint blockade, cell differentiation, cell fusion, proliferation, metastasis, and cell transformation. In addition, we summarize the involvement of HERV long terminal repeat (LTR) regions in transcriptional regulation, creation of fusion proteins, expression of long non-coding RNAs (lncRNAs), and promotion of genome instability through recombination.

The translational revolution in atopic dermatitis: the paradigm shift from pathogenesis to treatment

Atopic dermatitis (AD) is the most common inflammatory skin disease, and it is considered a complex and heterogeneous condition. Different phenotypes of AD, defined according to the patient age at onset, race, and ethnic background; disease duration; and other disease characteristics, have been recently described, underlying the need for a personalized treatment approach. Recent advancements in understanding AD pathogenesis resulted in a real translational revolution and led to the exponential expansion of the therapeutic pipeline. The study of biomarkers in clinical studies of emerging treatments is helping clarify the role of each cytokine and immune pathway in AD and will allow addressing the unique immune fingerprints of each AD subset. Personalized medicine will be the ultimate goal of this targeted translational research. In this review, we discuss the changes in the concepts of both the pathogenesis of and treatment approach to AD, highlight the scientific rationale behind each targeted treatment and report the most recent clinical efficacy data.

Short-term high fat feeding induces inflammatory responses of tuft cells and mucosal barrier cells in the murine stomach

Feeding mice with a high fat diet (HFD) induces inflammation and results in changes of gene expression and cellular composition in various tissues throughout the body, including the gastrointestinal tract. In the stomach, tuft cells expressing the receptor GPR120 are capable of sensing saturated long chain fatty acids (LCFAs) and thus may be involved in initiating mechanisms of mucosal inflammation. In this study, we assessed which cell types may additionally be affected by high fat feeding and which candidate molecular mediators might contribute to mucosa-protective immune responses. A high fat dietary intervention for 3 weeks caused an expansion of tuft cells that was accompanied by a higher frequency of mucosal mast cells and surface mucous cells which are a known source of the insult-associated cytokine interleukin 33 (IL-33). Our data demonstrate that both brush and mucosal mast cells comprise the enzyme ALOX5 and its activating protein FLAP and thus have the capacity for synthesizing leukotriene (LT). In HFD mice, several tuft cells showed a perinuclear colocalization of ALOX5 with FLAP which is indicative of an active LT synthesis. Monitoring changes in the expression of genes encoding elements of LT synthesis and signaling revealed that transcript levels of the leukotriene C4 synthase, LTC4S, catalyzing the first step in the biosynthesis of cysteinyl (cys) LTs, and the cysLT receptors, cysLTR2 and cysLTR3, were upregulated in mice on HFD. These mice also showed an increased expression level of IL-33 receptors, the membrane-bound ST2L and soluble isoform sST2, as well as the mast cell-specific protease MCPT1. Based on these findings it is conceivable that upon sensing saturated LCFAs tuft cells may elicit inflammatory responses which result in the production of cysLTs and activation of surface mucous cells as well as mucosal mast cells regulating gastric mucosal function and integrity.

Neuroserpin: A potential biomarker for early-onset severe preeclampsia

Preeclampsia is a hypertensive disease of pregnancy associated with intense inflammatory and pro-coagulant responses. Neuroserpin is a serine protease inhibitor that has been involved in neurological and immune processes and has not yet been investigated in preeclampsia. Herein, we evaluated neuroserpin levels in association with other inflammatory mediators (IL-17A, IL-33, and CXCL-16) during severe preeclampsia. The mediators' plasma levels were measured by immunoassays in 24 pregnant women with severe preeclampsia (early preeclampsia: N = 17, late preeclampsia: N = 7), 34 normotensive pregnant women, and 32 non-pregnant women. In general, pregnancy was associated with higher levels of neuroserpin, IL-17A, IL-33, and CXCL-16 than the non-pregnant state. However, this increase was attenuated in pregnancies complicated by severe preeclampsia. Although neuroserpin levels did not differ between normotensive pregnant women and pregnant women with severe preeclampsia, neuroserpin levels tended to be lower in early-onset than in late-onset severe preeclampsia. There were positive correlations between neuroserpin and IL-17A, neuroserpin and CXCL-16, and IL-17A and CXCL-16 levels in women with severe preeclampsia. In addition, although the risk for developing severe preeclampsia was higher in older women in this study, maternal age did not significantly influence the mediators' levels, nor their correlations in the preeclampsia group. In summary, our data suggest that neuroserpin might be a potential biomarker for early-onset severe preeclampsia and, that the imbalance among neuroserpin, IL-17A, IL-33, and CXCL-16 levels may be associated with the pathogenesis of preeclampsia, regardless of the maternal age.

Recovery of systemic hyperinflammation in patients with severe SARS-CoV-2 infection

INTRODUCTION

Patients with cardiovascular disease (CVD) and acute SARS-CoV-2 infection might show an altered immune response during COVID-19.

MATERIAL AND METHODS

Twenty-three patients with CVD and SARS-CoV-2 infection were prospectively enrolled and received a cardiological assessment at study entry and during follow-up visit. Inclusion criteria of our study were age older than 18 years, presence of CVD, and acute SARS-CoV-2 infection. The median age of the patient cohort was 69 (IQR 55-79) years. 12 (52.2%) patients were men. Peripheral monocytes and chemokine/cytokine profiles were analysed.

RESULTS

Numbers of classical and non-classical monocytes were significantly decreased during acute SARS-CoV-2 infection compared to 3-month recovery. While classical monocytes reached the expected level in peripheral blood after 3 months, the number of non-classical monocytes remained significantly reduced.

DISCUSSION

All three monocyte subsets exhibited changes of established adhesion and activation markers. Interestingly, they also expressed higher levels of pro-inflammatory cytokines like macrophage migration inhibitory factor (MIF) at the time of recovery, although MIF was only slightly increased during the acute phase.

CONCLUSION

Changes of monocyte phenotypes and increased MIF expression after 3-month recovery from acute SARS-CoV-2 infection may indicate persistent, possibly long-lasting, pro-inflammatory monocyte function in CVD patients.

Interleukin-22 and interleukin-33 show up-regulated levels in the serum of patients with mild/moderate Coronavirus disease 2019

Background

This study analyzed serum concentrations of interleukin (IL)-22 and IL-33 (pro-inflammatory and anti-inflammatory cytokines) in 90 patients with mild/moderate coronavirus disease 2019 (COVID-19) and 90 healthy controls. Enzyme-linked immunosorbent assay kits were used to measure IL-22 and IL-33 concentrations.

Results

Median (interquartile range) concentrations of IL-22 and IL-33 were significantly higher in patients than in controls (IL-22: 18.6 [18.0-19.3] vs. 13.9 [12.1-14.9] pg/mL, probability [p] < 0.001; IL-33: 37.8 [35.3-43.0] vs. 24.1 [23.0-26.2] pg/mL, p < 0.001). As indicated by the area under the curve (AUC), IL-22 and IL-33 were excellent predictors of COVID-19 (AUC = 0.95 and 0.892, respectively). Multinomial logistic regression analysis demonstrated that individuals with high production (> control median) of IL-22 (odds ratio = 17.80 [95% CI: 6.48-48.90]; p = 0.001) and IL-33 (odds ratio = 19.0 [95% CI: 7.4-48.6]; p = 0.001) were more likely to develop COVID-19. A positive correlation was found between IL-22 and IL-33 and both cytokines also showed positive correlations with granulocyte-to-lymphocyte ratio and erythrocyte sedimentation rate in all participants.

Conclusions

IL-22 and IL-33 showed up-regulated concentrations in the serum of patients with mild/moderate COVID-19. Both cytokines may have prognostic value for COVID-19 along with their association with disease risk.

The benefits of adipocyte metabolism in bone health and regeneration

Patients suffering from musculoskeletal diseases must cope with a diminished quality of life and an increased burden on medical expenses. The interaction of immune cells and mesenchymal stromal cells during bone regeneration is one of the key requirements for the restoration of skeletal integrity. While stromal cells of the osteo-chondral lineage support bone regeneration, an excessive accumulation of cells of the adipogenic lineage is thought to promote low-grade inflammation and impair bone regeneration. Increasing evidence indicates that pro-inflammatory signaling from adipocytes is responsible for various chronic musculoskeletal diseases. This review aims to summarize the features of bone marrow adipocytes by phenotype, function, secretory features, metabolic properties and their impact on bone formation. In detail, the master regulator of adipogenesis and prominent diabetes drug target, peroxisome proliferator-activated receptor γ (PPARG), will be debated as a potential therapeutic approach to enhance bone regeneration. We will explore the possibilities of using clinically established PPARG agonists, the thiazolidinediones (TZDs), as a treatment strategy to guide the induction of a pro-regenerative, metabolically active bone marrow adipose tissue. The impact of this PPARG induced bone marrow adipose tissue type on providing the necessary metabolites to sustain osteogenic-as well as beneficial immune cells during bone fracture healing will be highlighted.

Are IL-1 family cytokines important in management of sickle cell disease in Sub-Saharan Africa patients?

Introduction

Sickle cell disease (SCD) is the most common genetic disease found in Africa and throughout the world. It is responsible for a high rate of hemolysis, systemic inflammation, and modulation of the immune system with the involvement of immunological molecules, such as cytokines. IL-1β is a major inflammatory cytokine. IL-18 and IL-33, members of IL-1 family, also exhibit characteristics of inflammation-related cytokines. Thus, in order to contribute to the evaluation of the severity and prognosis of SCD in Africa, this study aimed to estimate the cytokine response, in particular the levels of cytokines of the IL-1 family, in sickle cell patients living in a Sub-Saharan country.

Methods

Ninety patients with a diagnosis of SCD were recruited with different hemoglobin types. Samples were assessed for cytokine levels using the Human Inflammation Panel assay from BioLegend. The assay allows the simultaneous quantification of 13 human inflammatory cytokines/chemokines, i.e., IL-1β, IFN-α2, IFN-γ, TNFα, MCP-1 (CCL2), IL-6, IL-8 (CXCL8), IL-10, IL-12p70, IL-17A, IL-18, IL-23, and IL-33.

Results and discussion

the assessment of plasma cytokines in SCD patients revealed significantly increased levels of IL-1 family cytokines in crisis compared to steady state, suggesting a substantial involvement of these cytokines in clinical exacerbation. This suggests the possibility of a causal effect in the SCD pathology and can open the way to define better care, pointing toward new therapeutic avenues for sickle disease in Sub-Saharan Africa.

Resolution Potential of Necrotic Cell Death Pathways

During tissue damage caused by infection or sterile inflammation, not only damage-associated molecular patterns (DAMPs), but also resolution-associated molecular patterns (RAMPs) can be activated. These dying cell-associated factors stimulate immune cells localized in the tissue environment and induce the production of inflammatory mediators or specialized proresolving mediators (SPMs). Within the current prospect of science, apoptotic cell death is considered the main initiator of resolution. However, more RAMPs are likely to be released during necrotic cell death than during apoptosis, similar to what has been observed for DAMPs. The inflammatory potential of many regulated forms of necrotic cell death modalities, such as pyroptosis, necroptosis, ferroptosis, netosis, and parthanatos, have been widely studied in necroinflammation, but their possible role in resolution is less considered. In this review, we aim to summarize the relationship between necrotic cell death and resolution, as well as present the current available data regarding the involvement of certain forms of regulated necrotic cell death in necroresolution.

Interleukin-33 and Soluble ST2 as Potential Biomarkers of Cancer in Opium Users: A Nested Case-Control Study

BACKGROUND

Opium abuse is one of the social hazards in the Middle Eastern countries. Opium consumption attributes to various malignancies. However, the exact molecular mechanism of this correlation still remains unclear. Cancer and inflammation are closely correlated. Interleukin-33 (IL-33) and its receptors, transmembrane ST2 (ST2L) and soluble ST2 (sST2), have been significantly associated with tumorigenicity. The present study aimed to investigate whether IL-33 and sST2 levels serve as cancer biomarkers in opium users.

METHODS

Serum samples were collected from 100 opium users and 100 healthy non-opium users in a nested case-control design. The subjects with over five years of history of opium abuse were enrolled. To assess the incidence of malignancies, the opium users were followed up from 2014 to 2019. Serum levels of IL-33 and sST2 were measured using an ELISA kit. For comparison of IL-33 and sST2 levels between the groups, two-tailed Student's t test and Mann-Whitney U test were utilized, accordingly. Logistic regression analysis was performed to evaluate the influence of confounders on the incidence of cancer.

RESULTS

During the five-year follow-up, eight opium users were diagnosed with cancer. Cancer was developed by 9.3 folds in the individuals abusing opium compared to that in the non-opium users (P=0.040, OR=9.3; 95%CI [1.1-79.4]). Serum levels of IL-33 were found to be significantly higher in the opium users than those in the healthy control group (P=0.001). The sST2 levels were significantly lower in the opium users (P=0.001). The opium users with cancer exhibited significantly higher levels of IL-33 and lower levels of sST2 than the cancer-free ones (P=0.001).

CONCLUSION

Decline in sST2 levels and rise in the level of IL-33 are valuable biomarkers in predicting cancers. Regarding the significant alterations in the levels of these biomarkers in the opium users, as well as those in the opium users diagnosed with cancer, IL-33 and sST2 may serve as potential biomarkers in the early prediction of cancer.

FDA-Approved Amoxapine Effectively Promotes Macrophage Control of Mycobacteria by Inducing Autophagy

Antibiotic resistance poses a significant hurdle in combating global public health crises, prompting the development of novel therapeutics. Strategies to enhance the intracellular killing of mycobacteria by targeting host defense mechanisms offer numerous beneficial effects, which include reducing cytotoxicity caused by current lengthy anti-tubercular treatment regimens and slowing or circumventing the development of multidrug-resistant strains. The intracellular pathogen Mycobacterium tuberculosis infects macrophages and exploits host machinery to survive and multiply. Using a cell-based screen of FDA-approved drugs, we identified an antidepressant, Amoxapine, capable of inhibiting macrophage cytotoxicity during mycobacterial infection. Notably, this reduced cytotoxicity was related to the enhanced intracellular killing of Mycobacterium bovis BCG and M. tuberculosis within human and murine macrophages. Interestingly, we discovered that postinfection treatment with Amoxapine inhibited mTOR (mammalian target of rapamycin) activation, resulting in the induction of autophagy without affecting autophagic flux in macrophages. Also, inhibition of autophagy by chemical inhibitor 3-MA or knockdown of an essential component of the autophagic pathway, ATG16L1, significantly diminished Amoxapine's intracellular killing effects against mycobacteria in the host cells. Finally, we demonstrated that Amoxapine treatment enhanced host defense against M. tuberculosis in mice. In conclusion, our study identified Amoxapine as a novel host-directed drug that enhances the intracellular killing of mycobacteria by induction of autophagy, with concomitant protection of macrophages against death. IMPORTANCE The emergence and spread of multidrug-resistant (MDR) and extensive drug-resistant (XDR) TB urges the development of new therapeutics. One promising approach to combat drug resistance is targeting host factors necessary for the bacteria to survive or replicate while simultaneously minimizing the dosage of traditional agents. Moreover, repurposing FDA-approved drugs presents an attractive avenue for reducing the cost and time associated with new drug development. Using a cell-based screen of FDA-approved host-directed therapies (HDTs), we showed that Amoxapine inhibits macrophage cytotoxicity during mycobacterial infection and enhances the intracellular killing of mycobacteria within macrophages by activating the autophagy pathway, both in vitro and in vivo. These findings confirm targeted autophagy as an effective strategy for developing new HDT against mycobacteria.

Interrelationship and Sequencing of Interleukins4, 13, 31, and 33 - An Integrated Systematic Review: Dermatological and Multidisciplinary Perspectives

The interrelations and sequencing of interleukins are complex (inter)actions where each interleukin can stimulate the secretion of its preceding interleukin. In this paper, we attempt to summarize the currently known roles of IL-4, IL-13, IL-31, and IL-33 from a multi-disciplinary perspective. In order to conduct a comprehensive review of the current literature, a search was conducted using PubMed, Google Scholar, Medscape, UpToDate, and Key Elsevier for keywords. The results were compiled from case reports, case series, letters, and literature review papers, and analyzed by a panel of multi-disciplinary specialist physicians for relevance. Based on 173 results, we compiled the following review of interleukin signaling and its clinical significance across a multitude of medical specialties. Interleukins are at the bed rock of a multitude of pathologies across different organ systems and understanding their role will likely lead to novel treatments and better outcomes for our patients. New interleukins are being described, and the role of this inflammatory cascade is still coming to light. We hope this multi-discipline review on the role interleukins play in current pathology assists in this scope.

IL-33/ST2 axis in autoimmune disease

Interleukin-33 (IL-33) is a member of the IL-1 family and plays an ambivalent role in autoimmune diseases. IL-33 signals via the ST2 receptor and drives cytokine production in mast cells, basophils, eosinophils, NK cells, and T lymphocyte cells. The vital role of IL-33 as an active component gives rise to aberrant local and systemic damage which has been demonstrated in numerous inflammatory disorders and immune-mediated pathological conditions including multiple sclerosis (MS), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), psoriasis, Sjogren's syndrome, inflammatory bowel disease (IBD), etc. IL-33/ST2 axis can up-regulate pro-inflammatory cytokine release in autoimmune disease, however, in some metabolic diseases like diabetes mellitus type 1 IL-33 can be considered an anti-inflammatory cytokine. The purpose of this review is to discuss selected studies on IL-33/ST2 axis in autoimmune diseases and its potential role as a pathogenic or protective cytokine.

Cytokine- and chemokine-induced inflammatory colorectal tumor microenvironment: Emerging avenue for targeted therapy

Colorectal cancer (CRC) is a predominant life-threatening cancer, with liver and peritoneal metastases as the primary causes of death. Intestinal inflammation, a known CRC risk factor, nurtures a local inflammatory environment enriched with tumor cells, endothelial cells, immune cells, cancer-associated fibroblasts, immunosuppressive cells, and secretory growth factors. The complex interactions of aberrantly expressed cytokines, chemokines, growth factors, and matrix-remodeling enzymes promote CRC pathogenesis and evoke systemic responses that affect disease outcomes. Mounting evidence suggests that these cytokines and chemokines play a role in the progression of CRC through immunosuppression and modulation of the tumor microenvironment, which is partly achieved by the recruitment of immunosuppressive cells. These cells impart features such as cancer stem cell-like properties, drug resistance, invasion, and formation of the premetastatic niche in distant organs, promoting metastasis and aggressive CRC growth. A deeper understanding of the cytokine- and chemokine-mediated signaling networks that link tumor progression and metastasis will provide insights into the mechanistic details of disease aggressiveness and facilitate the development of novel therapeutics for CRC. Here, we summarized the current knowledge of cytokine- and chemokine-mediated crosstalk in the inflammatory tumor microenvironment, which drives immunosuppression, resistance to therapeutics, and metastasis during CRC progression. We also outlined the potential of this crosstalk as a novel therapeutic target for CRC. The major cytokine/chemokine pathways involved in cancer immunotherapy are also discussed in this review.

IL-33 biology in cancer: An update and future perspectives

Interleukin-33 (IL-33) is a member of the IL-1 family of cytokines that is constitutively expressed in the nucleus of epithelial, endothelial and fibroblast-like cells. Upon cell stress, damage or necrosis, IL-33 is released into the cytoplasm to exert its prime role as an alarmin by binding to its specific receptor moiety, ST2. IL-33 exhibits pleiotropic function in inflammatory diseases and particularly in cancer. IL-33 may play a dual role as both a pro-tumorigenic and anti-tumorigenic cytokine, dependent on tumor and cellular context, expression levels, bioactivity and the nature of the inflammatory environment. In this review, we discuss the differential contribution of IL-33 to malignant or inflammatory conditions, its multifaceted effects on the tumor microenvironment, while providing possible explanations for the discrepant findings described in the literature. Additionally, we examine the emerging and divergent functions of IL-33 in the nucleus, and aspects of IL-33 biology that are currently under-addressed.

Insights into IL-33 on inflammatory response during in vitro infection by Trypanosoma cruzi

Inflammatory and regulatory cytokines play an important role in the immunopathogenesis of Trypanosoma cruzi infection. Interleukin (IL)-33 is a member of the IL-1 superfamily of cytokines whose expression/production is upregulated following pro-inflammatory stimulation to alert the immune system in response to tissue stress or damage. The aim of this study was to evaluate the inflammatory profile induced in cultured J774 cells stimulated or not with IL-33 (10 ng/mL), with live parasites (1 × 10⁶ metacyclic trypomastigote forms) and/or total antigen, TcAg (100 µg/mL) and with both, IL-33 and TcAg/T. cruzi. The cultures were evaluated at 24 h and 48 h after addition of the stimuli. For this, the supernatants were collected for the measurement of TNF, IL-17, CCL2, and IL-10 by ELISA and of nitrite by the Griess method. TNF, IL-17, and CCL2 concentrations were elevated in the presence of TcAg or live T. cruzi parasites at 24 h, and the addition of IL-33 potentiated these effects at 48 h. In addition, the T. cruzi-amastigote forms reduced in those infected J774 cells stimulated with IL-33 at 48 h. In conclusion, the IL-33 elevated the production of the TNF, IL-17, and CCL2 in cultured J774 cells stimulated with T. cruzi and/or its antigen and reduced the intracellular parasites, providing impetus to new investigations on its potential actions on the parasite-induced inflammation.