Action Of IL-1 Research Articles

Effect of genetically engineered drugs in aseptic necrosis of the femoral head in rats

Bone tissue is a dynamic structure with a metabolic function. The maintenance of bone homeostasis is carried out due to the continuous process of its renewal, remodeling. At the same time, a number of pathological processes, such as ischemic catastrophe, can lead to a violation of the balance of maintaining the constancy of the bone structure. One of these diseases is aseptic necrosis of the femoral head. The presented study analyzes the dynamics of expression of genes involved in maintaining bone tissue homeostasis, changes in the histological picture during the development of aseptic necrosis of the femoral head in laboratory rats that did not receive genetically engineered drugs and against the background of the use of inhibitors of biological action IL-6, TNF-α. After induction of aseptic necrosis in the proximal epiphysis of the femur, the histological picture in animals of different groups was not the same. More preserved bone architectonics and a larger volume of bone plates were recorded in rats receiving genetically engineered drugs compared to animals without the introduction of biological agents. The latter also had the most vivid picture of osteodestruction with increased expression of proinflammatory cytokine genes. In animals, against the background of the use of drugs of inhibitors of the biological action of IL-6, TNF-α, from the second week after induction of aseptic necrosis of the mRNA, the profile of the spongiose bone of the proximal epiphysis of the femur tended to increase the expression of osteoreparation genes. At the same time, the greatest inhibition of osteoclastogenesis gene expression was obtained in rats after injection of a monoclonal antibody to the IL-6 receptor.

The Mechanism of Action of IL-2 in the Tumor Microenvironment and its Application in Melanoma

The Mechanism of Action of IL-2 in the Tumor Microenvironment and its Application in Melanoma

Role of Serum IFN-γ and IL-10 as Predictive Biomarkers of Vitiligo Disease Activity: A Case-Control Study

Abstract Background and Objectives: IFNγ is a pleiotropic cytokine and through the regulation of immunologically relevant genes, they coordinate a wide range of cellular programs.[1] As a potent pro-inflammatory cytokine, it plays a pivotal role to induce depigmentation in vitiligo. In this study, we aim to assess the role of IFNγ in the activity, duration and extent of the disease and the antagonistic action of IL-10 is also assessed in vitiligo. Materials and Methods: A case-control study was conducted with 100 study participants with 50 cases clinically diagnosed as Vitiligo and 50 controls. All patients underwent complete evaluation with detailed demographic parameters, history and physical examination. The severity of the disease was assessed clinically by Vitiligo Area Scoring Index (VASI) and Vitiligo Disease Activity Score (VIDA). And blood investigations done were IFN-γ and IL-10. Results: We observed significantly higher levels of serum IFNγ levels in the patient group when compared with those of the normal controls (p=0.002) and showed a positive correlation with the activity and severity of the disease with a significant VASI (p=0.05) and VIDA score (p=<0.001). The mean serum IL-10 (p<0.001) in patients with vitiligo was significantly lower than that in the control group. Conclusion: This study showed significantly high serum levels of IFN-γ and correspondingly low levels of IL-10. New strategies, such as the combination of IFNγ blockade with inhibition of other signalling pathways, may further improve IFNγ targeted immunotherapy of the disease.

The effect of the IL-6 monoclonal blocker on the course of aseptic femoral head necrosis in the experiment (pilot study)

Background There is currently no pathogenetically based treatment for aseptic necrosis of the femoral head. One of the most promising areas of possible targeted therapy is the use of genetically engineered drugs, including monoclonal blockers of proinflammatory cytokines, aimed at inhibiting inflammation and indirectly reducing the activity of osteodestruction. The aim of the work is to evaluate the effectiveness of the use of the IL-6 monoclonal blocker in the course of aseptic necrosis of the femoral head in an experiment.Purpose Evaluate the preliminary results of the use of the IL-6 monoclonal blocker in the course of aseptic necrosis of the femoral head in an experiment.Materials and methods Surgical induction of aseptic necrosis of the femoral head was performed in 18 male Wistar rats. The animals were divided into two groups of 9 individuals each. The first group did not receive any treatment, the second received therapy with a monoclonal IL-6 receptor blocker, starting from the second week of the experiment, one injection once every two weeks. All animals were removed from the experiment at 4, 6 and 8 weeks after the induction of aseptic necrosis, 3 rats from each group at a time. Total RNA was isolated from the femoral head on the aseptic necrosis side and the conditionally healthy side as a control. The expression of genes of regulatory proteins of osteogenesis was studied by PCR. To study the features of osteodestructive processes, histological examination of femoral head preparations in all animals was conducted.Results Histological preparations of femoral heads of the second group animals were characterized by less pronounced osteodestructive, chondrodestructive processes compared to the animals that did not receive therapy. The mRNA profile of the rats of the second group displayed an increase in the expression of genes encoding proteins involved in osteoreparation at all stages of the experiment. At the same time, the activity of genes encoding proteins of proinflammatory cytokines, regulatory molecules of osteoclastogenesis was reduced relative to the first group.Discussion The data obtained indicate an important role of inflammation in the regulation of osteodestruction. Inhibition of the biological action of IL-6 contributed to inhibition of the expression of osteoclastogenesis genes, increased activity of bone metabolism genes, and caused a decrease in the intensity of osteodestruction and activation of osteoreparation. Conclusion Preliminary results of the use of a monoclonal blocker of the proinflammatory cytokine IL-6 indicate the inhibition of osteodestructive and strengthening of osteoreparative processes due to the correction of the expression of bone metabolism genes during the progression of aseptic necrosis of the femoral head in rats in an experimental model.

Direct assessment of leukocyte signalling and cytokine secretion reveals exercise intensity-dependent reductions in anti-inflammatory cytokine action.

Circulating interleukin (IL)-6 and IL-10 concentrations are widely used to evaluate the anti-inflammatory effects of exercise but do not capture cytokine action at the cellular level. Whether and how acute exercise impacts anti-inflammatory cytokine action in humans is unknown. To determine how exercise intensity and pattern impact IL-6 and IL-10 action in blood leukocytes, 16 active adults (eight males/eight females; age: 30±3years; body mass index: 22.8±2.3kg/m2; : 51±6mL/kg/min) completed a no-exercise control condition (CTL) or isocaloric bouts of cycling performed below (moderate continuous exercise; MCE) or above (heavy continuous or heavy intermittent exercise; HCE or HIE, respectively) lactate threshold. Venous blood (before, after, 30min after and 90min after exercise) was analysed for immune cell subpopulations, plasma cytokine concentrations, anti-inflammatory cytokine action and monocyte phenotype. Exercise induced rapid leukocytosis (P<0.001) and increased plasma IL-6 (P<0.001), IL-10 (P=0.0145) and tumour necrosis factor-⍺ (TNF-⍺) (P=0.0338) concentrations in an intensity-dependent manner (HCE and/or HIE vs. CTL). These systemic changes coincided with a diminished ability of IL-10/6 to phosphorylate STAT3 (P<0.001) and inhibit TNF-⍺ secretion (P=0.0238) in blood leukocytes following HCE and HIE. Monocyte polarization experiments revealed lower CD80 [MCE (P=0.0933) and HIE (P=0.0187) vs. CTL] and a tendency for higher CD163 expression (HCE vs. CTL, P=0.0985), suggesting that hyporesponsiveness to anti-inflammatory cytokine action does not impede the ability of exercise to promote an anti-inflammatory monocyte phenotype. These findings provide novel insights into the immunomodulatory effects of exercise in humans and highlight the importance of directly measuring cellular cytokine action when evaluating the anti-inflammatory effects of exercise. KEY POINTS: Circulating cytokine concentrations are frequently used to evaluate the anti-inflammatory effects of exercise but may not capture changes in cytokine action occurring at the cellular level. We directly assessed anti-inflammatory cytokine action - measured using a combination of intracellular signalling and cytokine secretion ex vivo - in distinct immune cell subpopulations after acute calorie-matched exercise bouts differing in intensity and pattern. Anti-inflammatory cytokine action was blunted following higher intensity exercise despite corresponding increases in circulating cytokine concentrations and immune cell counts. Changes in cytokine action were not explained by changes in cytokine receptor expression on circulating immune cells. Our findings provide new insights into the immunomodulatory effects of exercise in humans and highlight the importance of directly measuring cellular cytokine action when evaluating the anti-inflammatory effects of exercise.

Abstract 5811: Ultralong CDR3 engineered interleukin-15 antibody fusion for T and NK cell expansion

Abstract Interleukin (IL)-15 is a promising immunotherapeutic cytokine for cancer treatment because it can stimulate the proliferation and cytotoxicity of CD8+ T lymphocytes and nature killer (NK) cells, similar to the action of IL-2, which has been used to treat metastatic melanoma and renal cancer. IL-15 may have improved pharmacologic properties over IL-2 because it doesn’t cause vascular leak syndrome or stimulate regulatory T cells. However, IL-15 is difficult to express as a stable soluble protein and has a short half-life in vitro and in vivo. To solve the problem, we designed an IL-15 ultralong CDR3 humanized bovine antibody fusion. Bovine ultralong CDR3 antibodies have a unique “stalk and knob” structure in which two antiparallel β-strands support a disulfide bonded knob protruding out of the antibody surface and forms a mini antigen binding domain. By replacing the knob domain with IL-15, we have created a chimeric CDR3-IL-15 IgG which functions as IL-15 in vitro and in vivo but can be easily produced in mammalian cells with increased stability. Thus, the CDR3 can stabilize IL-15 in the absence of its high affinity receptor α (Rα) chain. Furthermore, as IL-15 utilizes Rα for increased trans signaling to the receptor β and γ subunits, one variant candidate (CDR3-IL-15_Rα) was produced by co-expressing Rα sushi domain with the chimeric IgG. Both constructs have been demonstrated to be highly active in stimulating proliferation of NK cells and CD8+ T cells in vitro as well as in stimulating proliferation of NK cells and CD8+ T cells in rats and non-human primates (NHP). Although the CDR3-IL-15_Rα exhibited higher in vitro signaling activity than CDR3-IL-15, both were equally potent in stimulating the proliferation of NK cells and CD4+ and CD8+ T cells in NHP without any immunogenicity detected. Moreover, in vivo studies in NHP indicated that CDR3-IL-15 acted faster than CDR3-IL-15_Rα in stimulating the proliferation of these lymphocytes. CDR3-IL-15 is the first thermodynamically stabilized variant of IL-15 produced in the absence of its Rα chain, is highly active in vivo, and has multiple potential cancer applications as an T and NK cell stimulating agent. Citation Format: Ruiqi Huang, Duncan McGregor, Vaughn Smider. Ultralong CDR3 engineered interleukin-15 antibody fusion for T and NK cell expansion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5811.

Increased Soluble Interleukin 6 Receptors in Fabry Disease.

Fabry disease (FD) is an X-linked lysosome storage disease that results in the accumulation of globotriaosylceramide (Gb3) throughout the body leading to irreversible target organ damage. As the role of secondary mediators (inflammatory molecules) and their mechanisms has not been fully elucidated, we focused on the interleukin (IL)-6 system in adult FD patients and in matched healthy subjects. To obtain insights into the complex regulation of IL-6 actions, we used a novel approach that integrates information from plasma and exosomes of FD patients (n = 20) and of healthy controls (n = 15). Soluble IL-6 receptor (sIL-6R) levels were measured in plasma with the ELISA method, and membrane-bound IL-6R was quantified in plasma and urinary exosomes using flow cytometry. In FD patients, the levels of soluble IL-6R in plasma were higher than in control subjects (28.0 ± 5.4 ng/mL vs. 18.9 ± 5.4 ng/mL, p < 0.0001); they were also higher in FD subjects with the classical form as compared to those with the late-onset form of the disease (36.0 ± 11.4 ng/mL vs. 26.1 ± 4.5 ng/mL, p < 0.0001). The percentage of urinary exosomes positive for IL-6R was slightly lower in FD (97 ± 1 vs. 100 ± 0% of events positive for IL-6R, p < 0.05); plasma IL-6 levels were not increased. These results suggest a potential role of IL-6 in triggering the inflammatory response in FD. As in FD patients only the levels of sIL-6Rs are consistently higher than in healthy controls, the IL-6 pathogenic signal seems to prevail over the homeostatic one, suggesting a potential mechanism causing multi-systemic damage in FD.

Lymphoma-Derived IL-10 Is a Key Immunomodulatory Factor at the Tumor Microenvironment of Activated B-Cell Diffuse Large B-Cell Lymphoma and Influences In Vivo Responses to Immunotherapy

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of aggressive non-Hodgkin's lymphoma with ~40% of patients experiencing refractory or relapsed disease to R-CHOP immunochemotherapy. These higher risk patients often exhibit gene expression profiles that resemble a late germinal center-derived activated B-cell (ABC) phenotype, where diverse specific mutations in genes along BCR and TLR signaling pathways converge into constitutive activation of the NF-κB pathway. Identification of factors that contribute to the survival of malignant ABC-DLBCL cells is crucial for designing specific interventions. In this setting, previous in vitro studies in DLBCL cell lines have evidenced that IL-10 is a direct target of NF-κB signaling that sustains lymphoma cell survival by an auto-stimulatory loop via STAT3 signaling. However, the action of IL-10 could be more complex within the lymphoma microenvironment, as IL-10 can have both stimulatory and inhibitory effects depending on the cellular source of IL-10, the timing of its secretion, and the type of immune cells that receives signals via IL-10 receptor (IL-10R). To explore in vivo the relevance of lymphoma-derived IL-10, we have generated a novel quintuple transgenic mouse model that we call pBIC10, after crossing our previous ABC-DLBCL-like pBIC mice carrying constitutive NF-κB signaling (Pascual et al., Blood 2019) to mice with a floxed Il10 gene for conditional knock-out of IL-10 specifically in malignant ABC-DLBCL cells. As expected, increased intracellular IL-10 signaling was detected in primary murine DLBCL cells from pBIC mice but not in IL-10 deficient pBIC10 mice, which promoted lymphoma cell survival ex vivo as revealed by perturbation studies of the IL-10/JAK1/STAT3 autocrine loop with blocking monoclonal antibodies or selected inhibitors. However, in vivo genetic deletion of lymphoma-derived IL-10 did not offer improved overall survival but, on the contrary, notably accelerated DLBCL progression in pBIC10 mice (Figure 1A, left). A comprehensive integration of multiparametric flow cytometry and transcriptomic analyses using bulk and single-cell RNA-seq of lymphoma cells and the tumor microenvironment coupled with BCR- and TCR-seq, identified lymphoma-derived IL-10 as a key immunomodulator of the DLBCL microenvironment, including unexpected protective paracrine functions in the progression of DLBCL. By comparing IL-10-proficient (pBIC) and -deficient (pBIC10) murine DLBCL models, we observed a multifaceted role of IL-10 produced by DLBCL cells, enabling immune-effector processes (facilitating immune chemotaxis, antigen presentation, and IFNγ responses) that yielded higher percentages of long-lived stem-like CD8 +TCF-1 +PD-1 lo/int T cells and dendritic cells, while restraining PD-1/LAG3-driven T-cell exhaustion and reducing immunosuppression by CD4 +CD25 +FOXP3 + regulatory T (Treg) cells. Thus, depletion of lymphoma-derived IL-10 decreased T-cell cytotoxicity and increased Treg-driven immunosuppression, which collectively accelerated lymphoma development. Consequently, T-cell targeted immune-checkpoint therapy (with anti-PD-1 antibodies) was effective only in IL-10-proficient DLBCL but not in IL-10-deficient pBIC10 mice (Figure 1A, right). Further comparative studies between pBIC and pBIC10 mice showed that tumor vascularization and expression of B-cell calcium channels, which have been previously associated with sensitivity to rituximab, were counteracted by lymphoma-derived IL-10. Accordingly, anti-CD20-based targeting of lymphoma cells (with rituximab surrogate antibodies) showed best in vivo responses in IL-10-deficient DLBCL mice with respect to pBIC mice (Figure 1A, right). Consistent with this preclinical data, analyses of transcriptional IL-10-associated hallmarks to stratify DLBCL patients (Schmitz et al., NEJM 2018) identified better clinical responses to R-CHOP in patients with pBIC10-like DLBCL phenotype (Figure 1B). Collectively, our study provides new functional and mechanistic insights into the role of lymphoma-derived IL-10 in the pathogenesis of DLBCL and the restraint of an immunosuppressed tumor microenvironment, which holds predictive potential as a biomarker for immunotherapy responses in DLBCL.

Oncostatin M suppresses IL31RA expression in dorsal root ganglia and interleukin-31-induced itching.

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by intermittent itchy rash. Type 2 inflammatory cytokines such as interleukin (IL)-4, IL-13, and IL-31 are strongly implicated in AD pathogenesis. Stimulation of IL-31 cognate receptors on C-fiber nerve endings is believed to activate neurons in the dorsal root ganglion (DRG), causing itch. The IL-31 receptor is a heterodimer of OSMRβ and IL31RA subunits, and OSMRβ can also bind oncostatin M (OSM), a pro-inflammatory cytokine released by monocytes/macrophages, dendritic cells, and T lymphocytes. Further, OSM expression is enhanced in the skin lesions of AD and psoriasis vulgaris patients. The current study aimed to examine the contributions of OSM to AD pathogenesis and symptom expression. The expression levels of the OSM gene (OSM) and various cytokine receptor genes were measured in human patient skin samples, isolated human monocytes, mouse skin samples, and mouse DRG by RT-qPCR. Itching responses to various pruritogens were measured in mice by counting scratching episodes. We confirmed overexpression of OSM in skin lesions of patients with AD and psoriasis vulgaris. Monocytes isolated from the blood of healthy subjects overexpressed OSM upon stimulation with IL-4 or GM-CSF. Systemic administration of OSM suppressed IL31RA expression in the mouse DRG and IL-31-stimulated scratching behavior. In contrast, systemic administration of OSM increased the expression of IL-4- and IL-13-related receptors in the DRG. These results suggest that OSM is an important cytokine in the regulation of skin monocytes, promoting the actions of IL-4 and IL-13 in the DRG and suppressing the action of IL-31. It is speculated that OSM released from monocytes in skin modulates the sensitivity of DRG neurons to type 2 inflammatory cytokines and thereby the severity of AD-associated skin itch.

Biology of Interleukin-17 and Novel Therapies for Hidradenitis Suppurativa.

Skin disorders affect ∼40% of the human population. One of the most debilitating cutaneous disorders is Hidradenitis suppurativa (HS), a noncommunicable chronic inflammatory disease with an estimated global prevalence of 0.4% to 2.5%. In January 2011, high levels of IL-17 were discovered in skin lesions of HS patients. In the following years, translational and clinical research led to a better understanding of the pathogenesis of HS. In June 2023, more than 12 years after the initial note, secukinumab, an anti-IL-17A monoclonal antibody, was approved for the treatment of moderate to severe HS. This is the next milestone in improving the treatment of these patients after the approval of the anti-TNF-α monoclonal antibody adalimumab in 2015. In this review article, we present the IL-17 pathway in HS and discuss the use of secukinumab as a therapeutic option for this disease. Our review starts with a description of the epidemiology, clinical features, etiology, and pathogenesis of HS. An overview of the IL-17/IL-17 receptor system in general and a detailed description of the known facts about the expression and action of IL-17 in HS follow. Afterward, we consider the results of clinical trials evaluating the safety and efficacy of IL-17 inhibitors in HS. Finally, a comparison is made between secukinumab and adalimumab and the characteristics of the patients that may be particularly suitable for each of these biologics are described.

1587-P: The NADPH Oxidase 4 Regulates Anti-inflammatory Signals to Modulate Lipid Depot Distribution between Adipose Tissue and Liver

Excessive white adipose tissue (WAT) expansion and lipid load is associated with the onset of insulin resistance and Type 2 diabetes. In addition, lipid storage may “overflow” into the liver triggering the apparition of nonalcoholic fatty liver disease (NAFLD). Two major components linking white adipose tissue (WAT) dysfunction and NAFLD to insulin resistance are the deregulation of cellular redox homeostasis and the onset of chronic, low-grade inflammation. NADPH oxidases (NOX-es) produce oxidant molecules that control redox homeostasis and cytokine signaling in inflammatory cells. In particular, NOX4 is essential for the signal transduction of the transcription factor, Stat6 that mediates anti-inflammatory actions of IL-4 and IL-13. In order to elucidate the in vivo interaction between NOX4 and Stat6 and to assess their relevance in the onset of “obese” WAT and NAFLD, we created mice with double knock-out for NOX4 and Stat6 (DKO) and compared their metabolic phenotype to littermates with single NOX4 deletion (NOX4KO) upon a 13-week high-fat diet feeding (60 % of calorie from fat). DKO and NOX4KO mice displayed similar food intake. By contrast, DKO mice displayed less body weight gain than NOX4KO mice due to lower energy efficiency leading to reduced WAT accumulation. DKO mice shifted lipid deposition away from the WAT and enhanced lipid storage in the liver. DKO mice displayed similar fed and starved glucose levels with no alterations in glucose tolerance assessed by intra-peritoneal glucose tolerance tests. Gene expression analysis confirmed a less inflammatory state of both WAT and liver of DKO mice. Our results demonstrate that anti-inflammatory signaling is modulated by NOX4-derived signals in vivo in mice, and that NOX4 and IL-4/IL-13 interaction is a critical component in the regulation surplus lipid storage distribution between WAT and the liver. Disclosure I. Szanto: None. Funding Insuleman Foundation (ISZ-1); Foundation for the Innovation in Research in Cancer and Biological Sciences

Dupilumab in complex therapy for chronic rhinosinusitis with nasal polyps and asthma

Chronic Rhinosinusitis with Nasal Polyps (CRwNP) caused by T2 inflammation has a complex pathogenesis, for which treatment options include medical therapy (topical and systemic glucocorticosteroids, leuktriene inhibitors, etc.) and surgical therapy, often recurs and significantly reduces the quality of life for patients. Chronic rhinosinusitis with nasal polyps is common in patients with asthma and, particularly, severe asthma and an allergic reaction to nonsteroidal anti-inflammatory drugs. These conditions are in most cases associated with a common pathogenesis, including a type II immune response, hyperproduction of interleukins (IL) 4, 5 and 13, activation of eosinophils and tissue remodeling. Biological therapy which block the effect of IL-4, 5, 13 can significantly improve the condition of such patients. Dupilumab is a humanized IgG4 monoclonal antibody that targets the IL-4 receptor alpha chain (IL-4Rα), thereby blocking the action of IL-4 and IL-13. Currently, dupilumab is approved for asthma, CRwNP and atopic dermatitis. Dupilumab can reduce the number of exacerbations, treatment with systemic corticosteroids, improve the condition of the upper and lower respiratory tract and achieve an increase in FEV1 by 0.2–0.3 L, which leads to a significant control of these diseases. One of the topical issues is the choice of tactics choice of treatment tactics in patients with CRwNP, asthma and nasal septum deviation. This article presents a clinical case of a patient with severe asthma, CRwNP and deviated nasal septum receiving dupilumab for 4 months.

Effect of IL6 on the cancer-associated cachexia: a mini review

More than 20% of tumor patients die because of cancer-associated cachexia (CAC) which is considered a multifactorial syndrome that is characterized by loss of weight, adipose tissue, and skeletal muscle, as well as anemia, accompanied by systemic inflammation. CAC is associated with various agents including cytokines. IL-6 is one of the major proinflammatory and pleiotropic cytokines produced by several cell types which induces and blocks diverse signaling pathways related to cancers and their disorders. For instance, tumor-secreted IL6 is the main cytokine that dilapidated the adipocyte in CAC. IL-6 also plays an essential role in skeletal muscle loss. The involvement of IL-6 in cancer progression and metastasis emerges the hypothesis of its role as a prognostic factor or a treatment agent in CAC. So, with regard to the importance of CAC and its high incidence, it seems that a comprehensive study on the role and mechanism of action of IL-6 in CAC can fill the scientific gap in death resulting from CAC.

TLR-mediated immune activation is a strong suppressor of the Treg-attracting chemokine CCL22

Abstract The immunoregulatory chemokine CCL22 is mainly secreted by dendritic cells (DC) in lymph nodes and plays a crucial role in maintaining the balance between immune tolerance and efficient immune response by induction of intercellular contacts between DC and regulatory T cells (Treg) expressing the only so far known CCL22 receptor CCR4. In the absence of CCL22, the immune response to vaccination and cancer has been proven to be enhanced. In this work, we aimed to understand how activation of Toll-like receptors (TLR) modulates CCL22 levels mechanistically in vitro and in vivo. We observed that a bacterial infection with salmonella typhimurium and treatment with different TLR agonists such as Poly (I:C), LPS, R848 and CpG led to a potent and long-lasting suppression of systemic CCL22 in vivo. Furthermore, using in vitro co-cultures of DC, B cells and T cells, we identified TLR-mediated CCL22 suppression to be mediated by soluble factors derived from non-DC. Additionally, we pursued to investigate the underlying mechanism and could show in vitro that CCL22 suppression is particularly driven by redundant action of IL-10, IFN-α and IFN-γ. Moreover, inhibition of NF-κB reverted the CCL22-suppressing effect of CpG on splenocytes. In CpG-treated mice, Treg/DC contacts were diminished to the level known from Ccl22 −/−mice, an observation which links TLR-mediated CCL22 suppression to an immunological relevance. Taken together, we demonstrate that TLR signaling results in CCL22 downregulation via different cytokines, a mechanism which is potentially important to enable the induction of a strong immune response and efficient pathogen clearance in the setting of microbial infection.

Mutual connected IL-6, EGFR and LIN28/Let7-related mechanisms modulate PD-L1 and IGF upregulation in HNSCC using immunotherapy.

The development of techniques and immunotherapies are widely applied in cancer treatment such as checkpoint inhibitors, adoptive cell therapy, and cancer vaccines apart from radiation therapy, surgery, and chemotherapy give enduring anti-tumor effects. Minority people utilize single-agent immunotherapy, and most people adopt multiple-agent immunotherapy. The difficulties are resolved by including the biomarkers to choose the non-responders' and responders' potentials. The possibility of the potential complications and side effects are examined to improve cancer therapy effects. The Head and Neck Squamous Cell Carcinoma (HNSCC) is analyzed with the help of programmed cell death ligand 1 (PD-L1) and Insulin-like growth factor (IGF). But how IGF and PD-L1 upregulation depends on IL-6, EGFR, and LIN28/Let7-related mechanisms are poorly understood. Briefly, IL-6 stimulates gene expressions of IGF-1/2, and IL-6 cross-activates IGF-1R signaling, NF-κB, and STAT3. NF-κB, up-regulating PD-L1 expressions. IL-6/JAK1 primes PD-L1 for STT3-mediated PD-L1 glycosylation, stabilizes PD-L1 and trafficks it to the cell surface. Moreover, ΔNp63 is predominantly overexpressed over TAp63 in HNSCC, elevates circulating IGF-1 levels by repressing IGFBP3, and activates insulin receptor substrate 1 (IRS1).TP63 and SOX2 form a complex with CCAT1 to promote EGFR expression. EGFR activation through EGF binding extends STAT3 activation, and EGFR and its downstream signaling prolong PD-L1 mRNA half-life. PLC-γ1 binding to a cytoplasmic motif of elevated PD-L1 improves EGF-induced activation of inositol 1,4,5-tri-phosphate (IP3), and diacylglycerol (DAG) subsequently elevates RAC1-GTP. RAC1-GTP was convincingly demonstrated to induce the autocrine production and action of IL-6/IL-6R, forming a feedback loop for IGF and PD-L1 upregulation. Furthermore, the LIN28-Let7 axis mediates the NF-κB-IL-6-STAT3 amplification loop, activated LIN28-Let7 axis up-regulates RAS, AKT, IL-6, IGF-1/2, IGF-1R, Myc, and PD-L1, plays pivotal roles in IGF-1R activation and Myc, NF-κB, STAT3 concomitant activation. Therefore, based on a detailed mechanisms review, our article firstly reveals that IL-6, EGFR, and LIN28/Let7-related mechanisms mediate PD-L1 and IGF upregulation in HNSCC, which comprehensively influences immunity, inflammation, metabolism, and metastasis in the tumor microenvironment, and might be fundamental for overcoming therapy resistance.

Mechanisms by which dupilumab normalizes eicosanoid metabolism and restores aspirin-tolerance in AERD: A hypothesis

Aspirin-exacerbated respiratory disease (AERD) is associated with overproduction of proinflammatory cysteinyl leukotrienes (CysLTs), defective generation of anti-inflammatory prostaglandin E2 (PGE2), and reduced expression of the EP2 receptor for PGE2. Reduced PGE2 synthesis results from the downregulation of inducible COX-2. Because PGE2 signaling via EP2 inhibits the 5-lipoxygenase/leukotriene C4 synthase-dependent pathway, the deficient levels of both PGE2 and EP2 likely contribute to the excessive baseline production of cysteinyl leukotrienes in patients with AERD compared with in patients with aspirin-tolerant asthma. The COX-2 pathway is regulated by an autocrine metabolic loop involving IL-1β, IL-1 receptor type I, EP2, COX-2, membrane-bound PGE2 prostaglandin E2 synthase-1, and PGE2. Previous studies reported that this metabolic loop is dysregulated in patients with AERD. When the downexpressed EP2 receptor is normalized, the entire loop returns to its normal function. Cotreatment of airway cells from healthy subjects with IL-4 and IFN-γ induces alterations in the metabolic loop similar to those seen in patients with AERD. In these patients, IL-4, which is produced in excess in airways of patients with AERD, likely contributes to the alteration of normal functioning of the autocrine metabolic loop involving IL-1β, IL-1 receptor type I, EP2, COX-2, membrane-bound PGE2 prostaglandin E2 synthase-1, and PGE2. We hypothesized that by blocking IL-4 action, dupilumab normalizes EP2 expression and restores the normal functioning of the COX-2 pathway autocrine metabolic loop, thereby normalizing the synthesis of PGE2 and restoring aspirin tolerance.

The hormetic and hermetic role of IL-6.

Interleukin-6 is a pleiotropic cytokine regulating different tissues and organs in diverse and sometimes discrepant ways. The dual and sometime hermetic nature of IL-6 action has been highlighted in several contexts and can be explained by the concept of hormesis, in which beneficial or toxic effects can be induced by the same molecule depending on the intensity, persistence, and nature of the stimulation. According with hormesis, a low and/or controlled IL-6 release is associated with anti-inflammatory, antioxidant, and pro-myogenic actions, whereas increased systemic levels of IL-6 can induce pro-inflammatory, pro-oxidant and pro-fibrotic responses. However, many aspects regarding the multifaceted action of IL-6 and the complex nature of its signal transduction remains to be fully elucidated. In this review we collect mechanistic insight into the molecular networks contributing to normal or pathologic changes during advancing age and in chronic diseases. We point out the involvement of IL-6 deregulation in aging-related diseases, dissecting the hormetic action of this key mediator in different tissues, with a special focus on skeletal muscle. Since IL-6 can act as an enhancer of detrimental factor associated with both aging and pathologic conditions, such as chronic inflammation and oxidative stress, this cytokine could represent a "Gerokine", a determinant of the switch from physiologic aging to age-related diseases.

MO759: Indoxyl-Sulfate Activation of the AhR-NFΚB Pathway Promotes IL-6 Secretion and Subsequent Osteogenic Transition and Calcification of Interstitial Cells of the Aortic Valve

Abstract BACKGROUND AND AIMS Calcific aortic valve disease (CAVD) results from fibro-calcific degeneration of the aortic valve leaflets, causing haemodynamic disorders and major cardiovascular complications. In chronic kidney disease (CKD) patients, this pathological remodelling is more frequent, appears earlier, progresses more rapidly and leads to a mortality rate three times higher than in the general population. The uremic toxin indoxyl-sulfate (IS) is a powerful predictor of cardiovascular mortality in CKD patients and a strong promoter of aortic calcification. However, its role in aortic valve leaflets mineralization has never been studied. This work aimed to evaluate whether IS can influence the mineralization of primary human valvular interstitial cells (hVICs) cultured in vitro. METHOD Primary hVICs were isolated from aortic tricuspid valves collected from patients with CAVD undergoing valve replacement surgery at the Amiens Picardie University Hospital. The concentrations of IS used in this study were selected according to the EUTOX registry: IS normal [Isn]: 0.5 µg/mL, IS uremic [Isu]: 37 µg/mL and IS maximum [Ismax]: 233 µg/mL. Human VICs mineralization were induced by exposure to an osteogenic medium containing 2.4 mmol/L calcium and 2.5 mmol/L phosphate (pro-calcific condition) and quantified by the o-cresolphthalein complexone method. The osteogenic transition of hVICs was assessed by qRT-PCR following Bmp2 and Runx2 mRNA expression. The cells’ inflammatory potential was assessed by qRT-PCR and ELISA following IL-1β, IL-6 and TNF-α expression and secretion. Activation of NFkB pathway was studied by analysing the phosphorylation of P65 via western blot. A siRNA approach was used to determine the signaling pathway involved in the effects of IS. RESULTS In pro-calcific conditions, IS increased hVICs osteogenic transition and calcification in a concentration-dependent manner, an effect that was blocked in hVICs transfected with siRNA targeting AhR expression. Data obtained by western blot showed that the exposure to [ISu] and [ISmax] promoted P65 phosphorylation in an AhR dependent manner. Blockade of the NFкB pathway with siRNA targeting P65 inhibited IS-induced expression of Bmp2 and RunX2 as well as hVICs mineralization, suggesting that hVICs inflammation plays a key role in the procalcific effects of IS. Confirming this hypothesis, the exposure to [ISu] and [ISmax] increased the expression of IL-1β, IL-6 and TNF-α transcripts, an effect abolished by silencing AhR and P65. Interestingly, hVICs did not secrete TNF-α and produced only a very low quantity of IL-1β in response to IS. By contrast, the exposure to [ISu] and [ISmax] induced an important release of IL-6 in hVICs culture medium, which was blocked when AhR and P65 were silenced. In this model, the use of an antibody neutralizing IL-6 completely abolished IS-induced hVICs osteogenic transition and calcification. CONCLUSION Our study demonstrates that IS displays direct pro-calcific effects on primary hVICs through AhR-dependent activation of the NFkB pathway and subsequent release of IL-6. We report that the autocrine action of IL-6 is responsible for IS-induced hVICs osteogenic transition and calcification. The observation that antibodies neutralizing IL-6 can block IS pro-calcific effects might be of particular interest knowing that interventional studies evaluating the cardiovascular impact of anti-IL-6 antibodies in patients with CKD are underway.

Anti-tumor immunity by transcriptional synergy between TLR9 and STING activation.

Agonists for TLR9 and stimulator of IFN genes (STING) offer therapeutic applications as both anti-tumor agents and vaccine adjuvants, though their clinical applications are limited; the clinically available TLR9 agonist is a weak IFN inducer and STING agonists induce undesired type 2 immunity. Yet, combining TLR9 and STING agonists overcame these limitations by synergistically inducing innate and adaptive IFNγ to become an advantageous type 1 adjuvant, suppressing type 2 immunity, in addition to exerting robust anti-tumor activities when used as a monotherapeutic agent for cancer immunotherapy. Here, we sought to decipher the immunological mechanisms behind the synergism mediated by TLR9 and STING agonists and found that their potent anti-tumor immunity in a Pan02 peritoneal dissemination model of pancreatic cancer was achieved only when agonists for TLR9 and STING were administered locally, and was via mechanisms involving CD4 and CD8 T cells as well as the co-operative action of IL-12 and type I IFNs. Rechallenge studies of long-term cancer survivors suggested that the elicitation of Pan02-specific memory responses provides protection against the secondary tumor challenge. Mechanistically, we found that TLR9 and STING agonists synergistically induce IL-12 and type I IFN production in murine APCs. The synergistic effect of the TLR9 and STING agonists on IL-12p40 was at protein, mRNA and promoter activation levels, and transcriptional regulation was mediated by a 200 bp region situated 983 bp upstream of the IL-12p40 transcription initiation site. Such intracellular transcriptional synergy may hold a key in successful cancer immunotherapy and provide further insights into dual agonism of innate immune sensors during host homeostasis and diseases.

Relationship of Inflammatory Markers and Metabolic Syndrome in Postmenopausal Women.

The increased deposition of visceral fat in the postmenopause period increases the production of inflammatory cytokines and the release of tumor necrosis factor- α (TNF-α), interleukin-6 (IL-6), and decrease in IL-10. This study investigated the relationship between inflammatory biomarkers and metabolic syndrome (MS) in postmenopausal women considering different diagnostic criteria. We conducted a cross-sectional observational study based on STROBE. Data were collected regarding the diagnostic criteria for MS (International Diabetes Federation; NCEP (International Diabetes Federation (IDF), National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP-III), and Harmonized criteria), body composition, comorbidities, time without menstruation, values of IL-6, IL-10, and TNF-α. ANOVA, Kruskal–Wallis, Levene tests, ROC, and odds ratio were performed to analyze the data. The results showed no significant difference between the methods and no interaction between the method and the presence of MS. However, for the values of WC, body fat percentage, TNF-α, and IL-10/TNF-α ratio, a significant effect of MS was observed. In subjects with MS, lower values of body fat percentage and TNF-α and higher values of the IL-10/TNF-α ratio were also observed. The higher IL-10/TNF-α ratio in the MS group is related to the greater anti-inflationary action of IL-10. The IL-10/TNF-α ratio showed significant accuracy to discriminate patients with MS according to the NCEP-ATP III criteria.