The role of IL-17 and anti-IL-17 agents in the immunopathogenesis and management of autoimmune and inflammatory diseases

NR1D1 mitigates IL-17a-induced small airway remodeling in biomass smoke-induced COPD

INTRODUCTION

Biomass smoke (BS) exposure is a critical environmental risk factor for Chronic Obstructive Pulmonary Disease (COPD). In this study, mechanisms of biomass smoke (BS)-induced small airway disease are explored, with a focus on the roles of Interleukin-17a (IL-17a) and Nuclear Receptor Subfamily 1 Group D Member 1 (NR1D1).

METHODS

This study included 20 BS exposure COPD (BS-COPD) patients and 13 controls, who underwent chest high-resolution computed tomography (HRCT) scans to assess emphysema and small airway disease. The control group was divided into a low- and high BS exposure control group. Serum IL-17a levels were measured. Wild-type and IL-17a-/- B6/C57 mice were exposed to wood smoke to establish a COPD model in mice. Airway pathology was evaluated by histological analysis. The effects of IL-17a and NR1D1 on cell proliferation of BEAS-2b cells exposed to wood smoke particulate matter 2.5 were assessed in vitro using flow cytometry and Western blotting.

RESULTS

HRCT revealed significantly higher small airway disease and emphysema in BS-COPD patients compared to controls (p < 0.01). Small airway disease exhibited the strongest negative correlation with FEV1%predicted (r = -0.61, p = 0.004). High-exposure control group showed significant BS Index correlations with small airway disease (r = 0.81, p = 0.049) and emphysema (r = 0.87, p = 0.025). Serum IL-17a levels correlated with small airway disease in BS-COPD (r = 0.48, p = 0.033). The mouse model demonstrated higher airway wall thickness and small airway disease in IL-17a-/- mice exposed to wood smoke. In vitro, IL-17a promoted BEAS-2b cell proliferation, an effect enhanced by NR1D1 downregulation.

CONCLUSIONS

BS exposure drives emphysema and small airway disease in non-COPD individuals. NR1D1 downregulation exacerbates IL-17a-mediated remodeling in vitro, suggesting therapeutic potential.

TRIAL REGISTRATION

ChiCTR-OOC-16008692.

Tracking inflammation status for improving patient prognosis: A review of current methods, unmet clinical needs and opportunities

Inflammation is the body's response to infection, trauma or injury and is activated in a coordinated fashion to ensure the restoration of tissue homeostasis and healthy physiology. This process requires communication between stromal cells resident to the tissue compartment and infiltrating immune cells which is dysregulated in disease. Clinical innovations in patient diagnosis and stratification include measures of inflammatory activation that support the assessment of patient prognosis and response to therapy. We propose that (i) the recent advances in fast, dynamic monitoring of inflammatory markers (e.g., cytokines) and (ii) data-dependent theoretical and computational modeling of inflammatory marker dynamics will enable the quantification of the inflammatory response, identification of optimal, disease-specific biomarkers and the design of personalized interventions to improve patient outcomes - multidisciplinary efforts in which biomedical engineers may potentially contribute. To illustrate these ideas, we describe the actions of cytokines, acute phase proteins and hormones in the inflammatory response and discuss their role in local wounds, COVID-19, cancer, autoimmune diseases, neurodegenerative diseases and aging, with a central focus on cardiac surgery. We also discuss the challenges and opportunities involved in tracking and modulating inflammation in clinical settings.

The interleukin gene landscape: understanding its influence on inflammatory mechanisms in apical periodontitis

Apical periodontitis is a common inflammatory illness caused by microbial infections in the root canal system, which destroys the periapical tissue. This disease's course and severity are highly regulated by a complex interaction of host immunological responses and genetic variables, particularly interleukin (IL) gene polymorphisms. These genetic variants influence cytokine production, the inflammatory cascade, and the ability to resolve infections. Polymorphisms in important cytokines (e.g., IL-1β, IL-6, IL-10, TNF-α, and IL-17) have been linked to worsening or reducing inflammation, affecting the clinical presentation and chronicity of apical periodontitis. A thorough examination of the molecular and clinical consequences of interleukin polymorphisms in apical periodontitis is given in this article. It emphasizes their function in regulating bone resorption, tissue degradation, and immune cell signaling. Their value in enhancing diagnostic precision, forecasting disease susceptibility, and directing treatment approaches is demonstrated by the incorporation of genetic insights into clinical practice. Targeted therapies, like immunomodulatory drugs and cytokine inhibitors, have great potential to reduce inflammation and encourage periapical healing. Future studies should focus on population-based research to examine genetic variability across ethnic groups, functional investigations to clarify the mechanisms behind polymorphism-driven cytokine regulation, and longitudinal studies to evaluate illness trajectories. Furthermore, developments in precision medicine and bioinformatics could completely transform patient-specific strategies by providing customized treatments and diagnostics. This review highlights the necessity of a multidisciplinary strategy that integrates immunology, genetics, and clinical practice to maximize apical periodontitis therapy and enhance dental health outcomes worldwide.

STAT3 Signaling Pathway in Health and Disease

Signal transducer and activator of transcription 3 (STAT3) is a critical transcription factor involved in multiple physiological and pathological processes. While STAT3 plays an essential role in homeostasis, its persistent activation has been implicated in the pathogenesis of various diseases, particularly cancer, bone-related diseases, autoimmune disorders, inflammatory diseases, cardiovascular diseases, and neurodegenerative conditions. The interleukin-6/Janus kinase (JAK)/STAT3 signaling axis is central to STAT3 activation, influencing tumor microenvironment remodeling, angiogenesis, immune evasion, and therapy resistance. Despite extensive research, the precise mechanisms underlying dysregulated STAT3 signaling in disease progression remain incompletely understood, and no United States Food and Drug Administration (USFDA)-approved direct STAT3 inhibitors currently exist. This review provides a comprehensive evaluation of STAT3's role in health and disease, emphasizing its involvement in cancer stem cell maintenance, metastasis, inflammation, and drug resistance. We systematically discuss therapeutic strategies, including JAK inhibitors (tofacitinib, ruxolitinib), Src Homology 2 domain inhibitors (S3I-201, STATTIC), antisense oligonucleotides (AZD9150), and nanomedicine-based drug delivery systems, which enhance specificity and bioavailability while reducing toxicity. By integrating molecular mechanisms, disease pathology, and emerging therapeutic interventions, this review fills a critical knowledge gap in STAT3-targeted therapy. Our insights into STAT3 signaling crosstalk, epigenetic regulation, and resistance mechanisms offer a foundation for developing next-generation STAT3 inhibitors with greater clinical efficacy and translational potential.

Comparative Analysis of Short-Chain Fatty Acids and the Immune Barrier in Cecum of Dahe Pigs and Dahe Black Pigs

The intestinal immune barrier is a developed and complex immune system, and there is a fine synergy between it and the induced immune response. Short-chain fatty acids (SCFAs) are the main metabolites of intestinal microbial fermentation. In the cecum of pigs, SCFAs not only provide energy for the host but also participate in regulating the function of the intestinal immune system. The purpose of this study was to explore the mechanism of SCFAs in the regulation of immune gene expression in porcine cecum. SCFAs content and mRNA expression levels of immune genes in cecum were detected, and Gene Ontology (GO) function annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, Protein-Protein Interaction Networks (PPI) network construction, key gene identification, and correlation analysis were performed. The results showed that the content of SCFAs in the cecum of Dahe black pigs (DHB) was lower than that of Dahe pigs (DH). There were significant differences in mRNA expression of some immune genes between the two groups. GO functional annotation found terms related to cytokine activity and protein heterodimerization activity; the KEGG pathway was enriched in several pathways related to intestinal immunity. The PPI network identified Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-10 (IL-10), Interleukin-17A (IL-17A), and Interleukin-18 (IL-18) as key proteins. The correlation analysis showed that acetic acid and valerate were closely related to the immune response. In this study, the differences in cecal short-chain fatty acids and the immune barrier between Dahe pigs and Dahe black pigs were compared, which provided a theoretical basis for improving the intestinal immunity of pigs.

Innovative peptide therapeutics targeting IL17RA to regulate inflammatory responses

Interleukin-17 receptor A (IL17RA) is a critical mediator of pro-inflammatory cytokine signaling and a key immune checkpoint in autoimmune diseases. While monoclonal antibodies targeting IL17RA have demonstrated clinical efficacy, their high costs, complexity in production, and lack of oral bioavailability present significant limitations. In response to these challenges, we developed AL-8(0), a novel peptide specifically designed to inhibit the IL17A-IL17RA signaling pathway. AL-8(0) was synthesized with high purity and systematically evaluated for its binding affinity and anti-inflammatory activity. Biophysical and cellular assays confirmed the peptide's strong affinity for IL17RA and its ability to inhibit inflammatory cytokine production in IL17RA-expressing monocyte-macrophages and keratinocytes. Moreover, its anti-inflammatory effects were com-parable to IL17RA-targeting monoclonal antibodies and were dependent on IL17RA expression, as demonstrated by experiments using IL17RA-deficient cells. These results underscore AL-8(0)'s potential as a targeted therapeutic for autoimmune diseases, offering a peptide-based alternative with lower antigenicity, improved scalability, and potential for oral administration. This study lays the groundwork for further development of AL-8(0) and similar peptides as innovative treatments for inflammatory disorders driven by the IL17A-IL17RA pathway.

Proteogenomic characterization of molecular and cellular targets for treatment-resistant subtypes in locally advanced cervical cancers

We report proteogenomic analysis of locally advanced cervical cancer (LACC). Exome-seq data revealed predominant alterations of keratinization-TP53 regulation and O-glycosylation-TP53 regulation axes in squamous and adeno-LACC, respectively, compared to in early-stage cervical cancer. Integrated clustering of mRNA, protein, and phosphorylation data identified six subtypes (Sub1-6) of LACC among which Sub3, 5, and 6 showed the treatment-resistant nature with poor local recurrence-free survival. Elevated immune and extracellular matrix (ECM) activation mediated by activated stroma (PDGFD and CXCL1high fibroblasts) characterized the immune-hot Sub3 enriched with MUC5AChigh epithelial cells (ECs). Increased epithelial-mesenchymal-transition (EMT) and ECM remodeling characterized the immune-cold squamous Sub5 enriched with PGK1 and CXCL10high ECs. We further demonstrated that CIC mutations could trigger EMT activation by upregulating ETV4, and the elevation of the immune checkpoint PVR and neutrophil-like myeloid-derived suppressive cells (FCN1 and FCGR3Bhigh macrophages) could cause suppression of T-cell activation in Sub5. Increased O-linked glycosylation of mucin characterized adeno-LACC Sub6 enriched with MUC5AChigh ECs. These results provide a battery of somatic mutations, cellular pathways, and cellular players that can be used to predict treatment-resistant LACC subtypes and can serve as potential therapeutic targets for these LACC subtypes.

Evaluating the Efficacy of Capreomycin and Levofloxacin Combination Therapy in Multidrug-Resistant Tuberculosis Patients

Capreomycin (CMN) paired with levofloxacin (LEV) was tested in patients with multidrug-resistant pulmonary tuberculosis (MDR-PTB) for efficacy and immune function. The control group (40 cases) received conventional treatment and the observation group (40 cases) received CMN combined with LEV were established. Three months of intensification therapy and eighteen months of consolidation therapy were performed. The therapeutic effects (sputum negative conversion, lesion absorption, cavity shrinkage, and total effective rates), CD4+, CD8+, immunoglobulin A (IgA), IgM, IgG, interleukin-6 (IL-6), IL-17, tumor necrosis factor-α (TNF-α), serum alkaline phosphatase (ALP), aspartate aminotransferase (ALT), and alanine aminotransferase (AST) were assessed. Adverse reactions were compared. After treatment, the observation group performed at a higher sputum negative conversion rate, lesion absorption rate, cavity shrinkage rate, and total effective rate than the control group; CD4+, IgA, IgM, IgG, and IL-17 were increased and CD8+, IL-6, and TNF-α were decreased in both groups, and all of them were improved significantly in the observation group; ALP, ALT, and AST were elevated in both groups, but the differences between the observation and control groups were comparable. CMN combined with LEV is highly effective for MDR-PTB patients, enhancing immune function and reducing inflammation while having minimal effects on liver function.

Review of mechanisms and frontier applications in IL-17A-induced hypertension

Background

The immune system is closely related to hypertension. Hypertension is an immune disorder to a certain extent, and inflammation is the basis of abnormally elevated blood pressure (BP). The accumulation of T cells and their cytokines can increase BP and end organ damage. T cells are activated by antigen-presenting cells of the innate immune system or by the influence of a high-sodium diet, the self-environment, or the gut microbiota. These cells produce inflammatory factors and cytokines, such as interleukin-17A (IL-17A) in T helper 17 cells, causing vascular inflammation, hypertension, and target organ damage.

Methods

In this article, we provide an insightful review of the research progress regarding the role of IL-17A in the pathogenesis of hypertension and its effects on different organs while emphasizing the role of IL-17A and its mediated functions in the kidneys, brain, intestines, and vascular system in the development and progression of hypertension.

Results

At the organ level, IL-17A is involved in the development and progression of hypertension in the kidneys, brain, intestines, and blood vessels, interacting with multiple signal pathway.

Conclusions

These findings have significant implications for developing future immunomodulatory therapies, which may lead to the development of potential treatments for hypertension.

Advances in understanding the role of interleukins in pulmonary fibrosis (Review)

Pulmonary fibrosis (PF) is a progressive, irreversible disease characterized by heterogeneous interstitial lung tissue damage. It originates from persistent or repeated lung epithelial injury and leads to the activation and differentiation of fibroblasts into myofibroblasts. Interleukins (ILs) are a group of lymphokines crucial for immunomodulation that are implicated in the pathogenesis of PF. However, different types of ILs exert disparate effects on PF. In the present review, based on the effect on PF, ILs are classified into three categories: i) Promotors of PF; ii) inhibitors of PF; and iii) those that exert dual effects on PF. Several types of ILs can promote PF by provoking inflammation, initiating proliferation and transdifferentiation of epithelial cells, exacerbating lung injury, while other ILs can inhibit PF through suppressing expression of inflammatory factors, modulating the Th1/Th2 balance and autophagy. The present review summarizes the association of ILs and PF, focusing on the roles and mechanisms of ILs underlying PF.

IL-17A exacerbates synovial inflammation in osteoarthritis via activation of endoplasmic reticulum stress

The primary clinical manifestations of osteoarthritis (OA) are joint pain and restricted movement capabilities. Synovial inflammation, serving as an initiator of OA progression, intensifies cartilage damage via the generation of various deleterious agents, including pro-inflammatory cytokines and nociceptive mediators. Despite extensive research on modulating synovial inflammation to retard OA progression, the underlying pathophysiological mechanisms of synovial inflammation in OA remain elusive. Interleukin-17A (IL-17A), a pro-inflammatory cytokine released by activated T lymphocytes, is a therapeutic target for numerous inflammatory and autoimmune pathologies. This study investigates the role and mechanism of IL-17A in OA synovial inflammation using both in vivo and in vitro models and examines the impact of the endoplasmic reticulum stress (ERS) inhibitor, 4-Phenylbutyric Acid (4-PBA). Our findings indicate that IL-17A may be implicated in synovial inflammation through ERS and suggest a potential therapeutic direction for mitigating synovial inflammation in OA.

Exploring the Mechanism of Bufei Decoction in the Treatment of Bronchial Asthma Based on Network Pharmacology and Molecular Docking

BACKGROUND

Bufei decoction (BFD) is used in clinical practice to treat bronchial asthma (BA), although its molecular mechanism of action remains unclear.

OBJECTIVE

This study aimed to explore the molecular mechanism of BFD for treating BA.

METHODS

Network pharmacology and molecular docking predicted the molecular mechanism and the analysis results were verified using the ELISA kit and RT-qPCR.

RESULTS

There were 58 main active components and 121 potential targets in the BFD from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform( TCMSP), and 11 core targets were obtained from the protein-protein interactions(PPI) network. The gene ontology (GO) analysis found that the treatment of BA with BFD was mainly related to inflammatory reaction, membrane raft, cytokine activity, etc. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that it was mainly related to interleukin (IL)-17 signaling pathway, tumor necrosis factor (TNF) signaling pathway, PI3KAkt signaling pathway, etc. The molecular docking results showed that the main active ingredients had strong binding ability with core targets. BFD significantly reduced the TNF-α, IL-6, and IL-1β and increased the level of IL-10 in rats with BA. BFD also significantly reduced the mRNA level of PI3K, AKT1, and VEGFA while increasing the mRNA level of TP53 in rats.

CONCLUSION

This study used network pharmacology methods to predict the potential active ingredients, targets, and pathways of BFD in treating BA and explore its possible molecular mechanism, which provided a theoretical basis for further study.

Hypoxia Combined With Interleukin-17 Regulates Hypoxia-Inducible Factor-1α/Endothelial Nitric Oxide Synthase Expression in Pulmonary Artery Endothelial Cells

The pathogenesis of chronic thromboembolic pulmonary hypertension may be multifactorial and requires further studies. We explored alterations in pulmonary artery endothelial cells under the hypoxic and elevated interleukin-17 conditions that are commonly present in patients with chronic thromboembolic pulmonary hypertension. We measured the serum interleukin-17 levels in 10 chronic thromboembolic pulmonary hypertension patients and 10 healthy control persons. The expressions and localisations of hypoxia-inducible factor-1α and endothelial nitric oxide synthase were detected in tissues. The levels of hypoxia-inducible factor-1α, endothelial nitric oxide synthase, nitric oxide, and reactive oxygen species in cultured pulmonary artery endothelial cells were examined under hypoxia and/or interleukin-17 treatment. The serum interleukin-17 level was increased in chronic thromboembolic pulmonary hypertension patients. Hypoxia-inducible factor-1α was increased, and endothelial nitric oxide synthase was decreased in chronic thromboembolic pulmonary hypertension pulmonary vascular tissue. After receiving the hypoxia combined with interleukin-17 treatment, pulmonary artery endothelial cells showed increased levels of hypoxia-inducible factor-1α and phospho-endothelial nitric oxide synthase (Thr495) (p = 0.001 and 0.063, respectively) and a decreased level of endothelial nitric oxide synthase (p < 0.001). In addition, the nitric oxide level was significantly decreased (p = 0.001), whereas the reactive oxygen species level was insignificantly increased in pulmonary artery endothelial cells. Chronic thromboembolic pulmonary hypertension patients might experience increased inflammation and hypoxia due to dysregulation of the hypoxia-inducible factor-1α/endothelial nitric synthase pathway in pulmonary artery endothelial cells under inflammation and hypoxia, contributing to the pathogenesis of chronic thromboembolic pulmonary hypertension.

Crosstalk between ROS-inflammatory gene expression axis in the progression of lung disorders

A significant number of deaths and disabilities worldwide are brought on by inflammatory lung diseases. Many inflammatory lung disorders, including chronic respiratory emphysema, resistant asthma, resistance to steroids, and coronavirus-infected lung infections, have severe variants for which there are no viable treatments; as a result, new treatment alternatives are needed. Here, we emphasize how oxidative imbalance contributes to the emergence of provocative lung problems that are challenging to treat. Endogenic antioxidant systems are not enough to avert free radical-mediated damage due to the induced overproduction of ROS. Pro-inflammatory mediators are then produced due to intracellular signaling events, which can harm the tissue and worsen the inflammatory response. Overproduction of ROS causes oxidative stress, which causes lung damage and various disease conditions. Invasive microorganisms or hazardous substances that are inhaled repeatedly can cause an excessive amount of ROS to be produced. By starting signal transduction pathways, increased ROS generation during inflammation may cause recurrent DNA damage and apoptosis and activate proto-oncogenes. This review provides information about new targets for conducting research in related domains or target factors to prevent, control, or treat such inflammatory oxidative stress-induced inflammatory lung disorders.

TH17/Treg lymphocyte balance is regulated by beta adrenergic and cAMP signaling

BACKGROUND

Post-traumatic stress disorder (PTSD) is a debilitating psychological disorder that also presents with neuroimmune irregularities. Patients display elevated sympathetic tone and are at an increased risk of developing secondary autoimmune diseases. Previously, using a mouse model of repeated social defeat stress (RSDS) that recapitulates certain features of PTSD, we demonstrated that elimination of sympathetic signaling to T-lymphocytes specifically limited their ability to produce pro-inflammatory interleukin 17A (IL-17A); a cytokine implicated in the development of many autoimmune disorders. However, the mechanism linking sympathetic signaling to T-lymphocyte IL-17A production remained unclear.

METHODS

Using a modified version of RSDS that allows for both males and females, as well as ex vivo models of T-lymphocyte polarization, we assessed the impact and mechanism of adrenergic receptor blockade (genetically and pharmacologically) and catecholamine depletion on T-lymphocyte differentiation to IL-17A-producing subtypes (i.e., TH17).

RESULTS

Only pharmacological inhibition of the beta 1 and 2 adrenergic receptors (β1/2) significantly decreased circulating IL-17A levels after RSDS, but did not impact other pro-inflammatory cytokines (e.g.,IL-6, TNF-α, and IL-10). This finding was confirmed using RSDS with both global β1/2 receptor knock-out mice, as well as by adoptively transferring β1/2 knock-out T-lymphocytes into immunodeficient hosts. Ex vivo polarized T-lymphocytes produced significantly less IL-17A with the blockade of β1/2 signaling, even in the absence of exogenous sympathetic neurotransmitter supplementation, which suggested T-lymphocyte-produced catecholamines may be involved in IL-17A production. Furthermore, cyclic AMP (cAMP) was demonstrated to be mechanistically involved in driving IL-17A production in T-lymphocytes, and amplifying cAMP signaling could restore IL-17A deficits caused by the absence of β1/2 signaling. Last, removal of β1/2 and cAMP signaling, even in IL-17A polarizing conditions, promoted regulatory T-lymphocyte (Treg) polarization, suggesting adrenergic signaling plays a role in the switching between pro- and anti-inflammatory T-lymphocyte subtypes.

CONCLUSIONS

Our data depict a novel role for β1/2 adrenergic and cAMP signaling in the balance of TH17/Treg lymphocytes. These findings provide a new target for pharmacological therapy in both psychiatric and autoimmune diseases associated with IL-17A-related pathology.

Immunoregulation of Liver Fibrosis: New Opportunities for Antifibrotic Therapy

Liver fibrosis develops in response to chronic liver injury and is characterized by a sustained inflammatory response that leads to excessive collagen deposition by myofibroblasts. The fibrogenic response is governed by the release of inflammatory mediators from innate, adaptive, and innate-like lymphoid cells and from nonprofessional immune cells (i.e., epithelial cells, hepatic myofibroblasts, and liver sinusoidal endothelial cells). Upon removal of the underlying cause, liver fibrosis can resolve via activation of specific immune cell subsets. Despite major advances in the understanding of fibrosis pathogenesis, there is still no approved antifibrotic therapy. This review summarizes our current knowledge of the immune cell landscape and the inflammatory mechanisms underlying liver fibrosis progression and regression. We discuss how reprogramming immune cell phenotype, in particular through targeting selective inflammatory pathways or modulating cell-intrinsic metabolism, may be translated into antifibrogenic therapies.

CARD9 promotes cholangiocarcinoma by regulating the IL-17A/Hedgehog and the THEM4/AKT/mTOR signaling pathways

Cholangiocarcinoma (CCA) is a highly lethal malignant tumor originating from the bile duct, and its underlying mechanisms are not fully understood. In order to identify key genes in CCA, we downloaded gene expression data from public GSE76297, GSE26566 and TCGA-CHOL datasets. CARD9 was selected as a CCA-related gene from the datasets. Its expression was identified in the CCA tissues via PCR, western blot and immunohistochemistry assays. The loss-and-gain function assay of CARD9 was conducted in CCA cell lines (QBC939 and RBE) and nude mice. This study found a significant upregulation of CARD9 in CCA tissues, which is associated with poor prognosis in patients. Overexpression of CARD9 promotes proliferation and invasion of QBC939 and RBE cells, enhances the growth and development in CCA mouse models, and reduces sensitivity to chemotherapy drugs for CCA. Mechanistically, CARD9 activates the NF-κB and NLRP3 inflammatory signaling pathways, induces excessive release of various inflammatory factors, and triggers a cascade reaction of interleukin-17 (IL-17A). IL-17A promotes the stability of IHH mRNA by regulating HuR, enhances IHH transcription, and activates the Hedgehog signaling pathway to accelerate the progression of CCA. In addition, CARD9 promotes proliferation and invasion of CCA cells by interacting with THEM4, thereby facilitating AKT and mTOR phosphorylation, and accelerating the progression of CCA. Overall, these data suggest that CARD9 is involved in the progression of CCA by regulating the IL-17A/Hedgehog and the THEM4/AKT/mTOR signaling pathways. Therefore, CARD9 may serve as a novel therapeutic target for CCA treatment.

The role of interleukin-17 and interleukin-23 inhibitors in the development, progression, and recurrence of cancer: A systematic review

Background

Biologicals targeting interleukin (IL)-17 and IL-23 improve quality of life in psoriasis and other chronic autoimmune disorders with a favorable safety profile. However, current guidelines do not recommend their use in patients with recent oncologic history due to limited evidence.

Objective

To understand the impact of IL-17 and IL-23 inhibitors on cancer development, progression, and recurrence by systematically reviewing available literature.

Methods

We conducted a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Results

Most studies investigating the use of IL-23 and IL-17 blockers did not find a higher incidence of cancer compared to the general population. One study observed no relapse in patients with a history of cancer.

Limitations

The systematic review is limited due to variations in study designs and outcomes, making it difficult to achieve a comprehensive synthesis and comparison between studies. Furthermore, small sample sizes were notable.

Conclusion

Preclinical studies suggest that treating psoriasis with IL-17 or IL-23 blockers is safe, also in patients witch active cancer or a history of it. Pharmacovigilance data show no increased malignancy rate in patients treated with these treatment modalities. However, data on relapse in patients with a history or active malignancy are limited.

Progress in targeted therapy for ankylosing spondylitis: A review

Ankylosing spondylitis (AS) is a chronic inflammatory disease characterized by axial osteoarticular inflammation and tendon enthesitis with unclear pathogenesis. Nonsteroidal anti-inflammatory drugs and antirheumatic drugs used in the traditional treatment of AS have some problems such as drug intolerance and inadequate treatment response. Since the introduction of biological agents in the treatment of AS, they have completely changed the treatment concept of AS, and because of their safety and good tolerance, they have become the main choice for clinical AS patients. This article systematically summarizes the current status of targeted therapy for AS worldwide, analyzes the advantages and disadvantages of different types of biological agents in the treatment of AS, and provides an objective evaluation of clinical targeted therapy for AS, in order to provide a new perspective for clinical standardized treatment.

NR2E3 inhibits the inflammation and apoptosis in diabetic retinopathy by regulating the AHR/IL-17A signaling pathway

Diabetic retinopathy (DR) is the most prevalent microvascular complication of diabetes mellitus, and it is the primary cause of blindness in the working-age population worldwide. Nevertheless, the pathogenic molecular mechanisms of DR remain elusive. Hub genes were identified through bioinformatics analysis in the GSE102485 and GSE60436 datasets. The DR mouse model was induced using streptozotocin (STZ, 150 mg/kg), and pathological changes in retinal tissue were assessed via HE staining. Apoptosis in retinal tissue cells was evaluated by the TUNEL assay. RT-qPCR and ELISA assays were employed to measure hub genes and inflammatory factor levels, respectively. The aryl hydrocarbon receptor (AHR)/interleukin (IL)-17A (AHR/IL-17A) pathway-associated proteins were detected by western blot. In the high glucose (HG)-induced ARPE-19 cells, CCK-8 and flow cytometry were used to perform cell function studies. Six hub genes associated with DR were screened. The expression levels of RHO, PRPH2, CRX, RCVRN, and NR2E3 were reduced, while the COL1A2 was elevated. NR2E3 overexpression reduced inflammatory factor (TNF-α, IL-1β, and IL-6) and cell apoptosis levels in DR. Furthermore, NR2E3 overexpression promoted HG-induced ARPE-19 cell proliferation. Mechanistically, NR2E3 overexpression facilitated the protein expression of AHR, while suppressing the IL-17 and ACT1 expressions. The introduction of Kyn-101, an AHR inhibitor, notably reversed the inhibitory effects of NR2E3 overexpression on inflammation and apoptosis, which were validated both in vivo and in vitro. NR2E3 inhibits the inflammation and apoptosis by regulating the AHR/IL-17A pathway, providing new insights into the DR treatment.

Single-cell landscape of bronchoalveolar immune cells in patients with immune checkpoint inhibitor-related pneumonitis

The pathophysiology of immune checkpoint inhibitor-related pneumonitis remains incompletely understood. We conducted single-cell and T-cell receptor transcriptomic sequencing on the bronchoalveolar lavage fluid from five patients with grade ≥2 immune checkpoint inhibitor-related pneumonitis. Our analyses revealed a prominent enrichment of T cells in the bronchoalveolar lavage fluid of patients with immune checkpoint inhibitor-related pneumonitis. Within the CD4 + T cell subset, Tfh-like T cells were highly enriched and exhibited signatures associated with inflammation and clonal expansion. Regulatory T cells were also enriched and displayed enhanced inhibitory functions. Within the CD8 + T-cell subset, effector memory/tissue-resident memory T cells with an elevated cytotoxic phenotype were highly infiltrated. Among myeloid cells, alveolar macrophages were depleted, while pro-inflammatory intermediate monocytes were elevated. Dendritic cells demonstrated enhanced antigen presentation capabilities. Cytokines CXCR4, CXCL13, TNF-α, IFN-α, IFN-γ, and TWEAK were elevated. Through a comprehensive single-cell analysis, we depicted the landscape of immune checkpoint inhibitor-related pneumonitis.

Role of Interleukin-17 in Predicting Activity of Rheumatoid Arthritis and Systemic Lupus Erythematosus

Background

Although high serum levels of interleukin (IL)-17 and its producing cells have been found in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) in earlier research, it is still unclear how these findings relate to disease activity.

Objectives

This study examines the link between serum levels of IL-17 and the activity of both RA and SLE.

Design

This pilot case-control study included 100 patients with RA, 100 with SLE, and 100 healthy controls.

Methods

The Disease Activity Score-28 (DAS28) scores assessed the activity of RA, whereas the Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) scores assessed SLE activity. All participants' data were compared and correlated.

Results

Serum levels of IL-17 were significantly higher in RA and SLE patients compared with the controls (P < .001) and showed significantly positive correlations (P < .001) with rheumatoid factor titer, anti-cyclic citrullinated peptide (anti-CCP) and DAS28 score among the RA patients. Although among SLE patients, they were significantly positively correlated (P < .001) with anti-double-stranded DNA (anti-ds DNA) levels and the SLEDAI-2K scores, the best cut-off value of IL-17 for predicting moderate and high disease activity was > 175 pg/mL among RA patients and > 95 pg/mL among SLE patients.

Conclusions

There is a significant correlation between RA and SLE activity and serum levels of IL-17. This discovery emphasizes IL-17 as a potential therapeutic target.

IL-17 signaling pathway: A potential therapeutic target for reducing skeletal muscle inflammation

BACKGROUND

The interleukin-17 (IL-17) signaling pathway is intricately linked with immunity and inflammation; however, the association between the IL-17 signaling pathway and skeletal muscle inflammation remains poorly understood. The study aims to investigate the role of the IL-17 signaling pathway in skeletal muscle inflammation and to evaluate the therapeutic potential of anti-IL-17 antibodies in reducing muscle inflammation.

METHODS

A skeletal muscle inflammation model was induced by cardiotoxin (CTX) injection in C57BL6/J mice. Following treatment with an anti-IL-17 antibody, we conducted a comprehensive analysis integrating single-cell RNA sequencing (scRNA-seq), bioinformatics, enzyme-linked immunosorbent assay (ELISA), immunofluorescence, and Western blot techniques to elucidate underlying mechanisms.

RESULTS

scRNA-seq analysis revealed a significant increase in neutrophil numbers and activity in inflamed skeletal muscle compared to other cell types, including macrophages, T cells, B cells, endothelial cells, fast muscle cells, fibroblasts, and skeletal muscle satellite cells. The top 30 differentially expressed genes within neutrophils, along with 55 chemokines, were predominantly enriched in the IL-17 signaling pathway. Moreover, the IL-17 signaling pathway exhibited heightened expression in inflamed skeletal muscle, particularly within neutrophils. Treatment with anti-IL-17 antibody resulted in the suppression of IL-17 signaling pathway expression, accompanied by reduced levels of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α, as well as decreased numbers and activity of Ly6g+/Mpo+ neutrophils compared to CTX-induced skeletal muscle inflammation.

CONCLUSION

Our findings suggest that the IL-17 signaling pathway plays a crucial role in promoting inflammation within skeletal muscle. Targeting this pathway may hold promise as a therapeutic strategy for ameliorating the inflammatory micro-environment and reducing cytokine production.

IL-10 and TGF-β, but Not IL-17A or IFN-γ, Potentiate the IL-15-Induced Proliferation of Human T Cells: Association with a Decrease in the Expression of β2m-Free HLA Class I Molecules Induced by IL-15

IL-15 is a homeostatic cytokine for human T and NK cells. However, whether other cytokines influence the effect of IL-15 is not known. We studied the impact that IL-10, TGF-β, IL-17A, and IFN-γ have on the IL-15-induced proliferation of human T cells and the expression of HLA class I (HLA-I) molecules. Peripheral blood lymphocytes (PBLs) were labeled with CFSE and stimulated for 12 days with IL-15 in the absence or presence of the other cytokines. The proportion of proliferating T cells and the expression of cell surface HLA-I molecules were analyzed using flow cytometry. The IL-15-induced proliferation of T cells was paralleled by an increase in the expression of HC-10-reactive HLA-I molecules, namely on T cells that underwent ≥5-6 cycles of cell division. It is noteworthy that the IL-15-induced proliferation of T cells was potentiated by IL-10 and TGF-β but not by IL-17 or IFN-γ and was associated with a decrease in the expression of HC-10-reactive molecules. The cytokines IL-10 and TGF-β potentiate the proliferative capacity that IL-15 has on human T cells in vitro, an effect that is associated with a reduction in the amount of HC-10 reactive HLA class I molecules induced by IL-15.

Identification of LPCAT1 as a key biomarker for Crohn's disease based on bioinformatics and machine learnings and experimental verification

Epithelial-mesenchymal transition (EMT) plays a crucial role in regulating inflammatory responses and fibrosis formation. This study aims to explore the molecular mechanisms of EMT-related genes in Crohn's disease (CD) through bioinformatics methods and identify potential key biomarkers. In our research, we identified differentially expressed genes (DEGs) related to EMT based on the GSE52746 dataset and the gene set in the GeneCards database. Key genes were identified through Lasso-cox and Random Forest and validated using the external dataset GSE10616. Immune infiltration analysis showed that Lysophosphatidylcholine acyltransferase 1 (LPCAT1) was positively correlated with Neutrophils and Macrophages M1. The Gene Set Enrichment Analysis (GSEA) results for LPCAT1 showed associations with celladhesionmolecules and ECM receptor interaction. Additionally, a lncRNA-miRNA-mRNA ceRNA network was constructed. Finally, we validated that knocking down LPCAT1 could inhibit the release of inflammatory factors, EMT, and the elevation of fibrosis indices as well as the activation of NF-κB signaling pathway in LPS-induced HT-29 cells. LPCAT1 plays an important role in the occurrence and development of CD and may become a new biomarker.

Complement Component C5a and Fungal Pathogen Induce Diverse Responses through Crosstalk between Transient Receptor Potential Channel (TRPs) Subtypes in Human Conjunctival Epithelial Cells

The conjunctiva has immune-responsive properties to protect the eye from infections. Its innate immune system reacts against external pathogens, such as fungi. The complement factor C5a is an important contributor to the initial immune response. It is known that activation of transient-receptor-potential-vanilloid 1 (TRPV1) and TRP-melastatin 8 (TRPM8) channels is involved in different immune reactions and inflammation in the human body. The aim of this study was to determine if C5a and mucor racemosus e voluminae cellulae (MR) modulate Ca2+-signaling through changes in TRPs activity in human conjunctival epithelial cells (HCjECs). Furthermore, crosstalk was examined between C5a and MR in mediating calcium regulation. Intracellular Ca2+-concentration ([Ca2+]i) was measured by fluorescence calcium imaging, and whole-cell currents were recorded using the planar-patch-clamp technique. MR was used as a purified extract. Application of C5a (0.05-50 ng/mL) increased both [Ca2+]i and whole-cell currents, which were suppressed by either the TRPV1-blocker AMG 9810 or the TRPM8-blocker AMTB (both 20 µM). The N-terminal peptide C5L2p (20-50 ng/mL) blocked rises in [Ca2+]i induced by C5a. Moreover, the MR-induced rise in Ca2+-influx was suppressed by AMG 9810 and AMTB, as well as 0.05 ng/mL C5a. In conclusion, crosstalk between C5a and MR controls human conjunctival cell function through modulating interactions between TRPV1 and TRPM8 channel activity.

Xuanbi Yuyang Decoction Ameliorates DSS-Induced Colitis by Inhibiting Pyroptosis via Blocking of IL-17 Pathway Activation

Background

Ulcerative colitis (UC), a highly relapsing non-specific disease, is difficult to cure completely. The investigation aims to determine the protective effect and potential action mechanism of Xuanbi yuyang decoction (XBD) on UC.

Methods

The chemical composition of XBD was determined through non-targeted metabolomics analysis. Subsequently, experimental mice were orally given 3% DSS for 6 days, followed by XBD treatment (0.3 mL, 0.4 mL). In vitro, the human colon epithelial cells were co-treated with DSS and medicated serum. The therapeutic effects of XBD on UC were evaluated in vivo and vitro. The mechanisms of XBD against UC were determined by detecting hallmarks related to pyroptosis and Interleukin (IL)-17 pathways using Western blot and ELISA. The recombinant human interleukin 17A (rhIL17A) and was applied for further verifying the effect of XBD on IL-17 pathway in UC cells.

Results

XBD supplementation restored DSS-induced weight loss, colon shortening and tissue damage, and reduced DAI. Moreover, XBD enhanced viability, repaired the intestinal mucosal barrier of colitis, decreased pro-inflammatory cytokines levels, and inhibited pyroptosis. Additionally, DSS increased the expression of IL-17 pathway was and cytokines (IL-17A, IL-6), which were blocked by XBD treatment. The rhIL17A treatment attenuated protective effect against DSS-induced colitis and could also enhance pyroptosis.

Conclusion

XBD has a favorable protective effect against DSS-induced colitis through restraining pyroptosis via inhibition of IL-17 signaling pathway activation, suggesting XBD may be a new and effective treatment therapy for UC.

Rare Case Report of Primary Active Pulmonary Tuberculosis During Ixekizumab Treatment for Plaque Psoriasis

Biologic agents have become a mainstay in the treatment of psoriasis, particularly in moderate to severe, refractory, and special types of the disease. Among these, ixekizumab is a humanized IgG4 monoclonal antibody targeting interleukin-17A, approved for the treatment of moderate to severe plaque psoriasis. Its adverse effects include infections such as nasopharyngitis, upper respiratory tract infections, and injection site reactions. While the incidence of tuberculosis (TB) associated with IL-17A antagonists is extremely low, this paper reports a case of active pulmonary tuberculosis occurring after ten doses of ixekizumab treatment for chronic plaque psoriasis. This highlights the importance for clinicians to remain vigilant regarding tuberculosis infection in patients undergoing therapy with this class of medications, emphasizing the need for enhanced screening and monitoring for tuberculosis during treatment.

A new mechanism in negative pressure wound therapy: interleukin-17 alters chromatin accessibility profiling

Negative pressure wound therapy (NPWT) is extensively used in clinical settings to enhance the healing of wounds. Despite its widespread use, the molecular mechanisms driving the efficacy of NPWT have not been fully elucidated. In this study, skin wound-healing models were established, with administration of NPWT. Vimentin, collagen I, and MMP9 of skin tissues were detected by immunofluorescence (IF). Gene expression analysis of skin wound tissues was performed by RNA-sequencing (RNA-seq). Protein expression was assayed by a Western blotting or IF assay, and mRNA levels were quantified by quantitative PCR. Chromatin accessibility profiles of fibroblasts following NPWT or IL-17 exposure were analyzed by ATAC-seq. In rat wound-healing models, NPWT promoted wound repair by promoting reepithelialization, extracellular matrix (ECM) synthesis, and proliferation, which mainly occurred in the early stage of wound healing. These differentially expressed genes (DEGs) in NPWT wounds versus control wounds were enriched in the IL-17 signaling pathway. IL-17 was identified as an upregulated factor following NPWT in skin wounds. Moreover, the IL-17 inhibitor secukinumab (SEC) could abolish the promoting effect of NPWT on wound healing. Importantly, chromatin accessibility profiles were altered following NPWT and IL-17 stimulation in skin fibroblasts. Our findings suggest that NPWT upregulates IL-17 to promote wound healing by altering chromatin accessibility, which is a novel mechanism for NPWT's efficacy in wound healing.NEW & NOTEWORTHY To our knowledge, this is the first report of the efficacy of negative pressure wound therapy (NPWT) in promoting wound healing via IL-17. Moreover, NPWT and IL-17 can alter chromatin accessibility. Our study identifies a novel mechanism for NPWT's efficacy in wound healing.

Cornuside alleviates psoriasis-like skin lesions in mice by relieving inflammatory effects

Psoriasis is a chronic inflammatory skin disease substantially affecting the quality of life, with no complete cure owing to its complex pathogenesis. Cornuside, a major bioactive compound present in Cornus officinalis Sieb. et Zucc., which is a well-known traditional Chinese medicine with a variety of biological and pharmacological activities, such as anti-apoptotic, antioxidant, and anti-inflammatory properties. However, its effects on psoriasis remain unclear. Our preliminary analysis of network pharmacology showed that cornuside may be involved in psoriasis by regulating the inflammatory response and IL-17 signaling pathway. Thus, we investigated the protective role and mechanism of cornuside in the pathogenesis of psoriasis in an imiquimod (IMQ)-induced psoriasis mouse model. In-vivo experiments demonstrated that cornuside-treated mice had reduced skin erythema, scales, thickness, and inflammatory infiltration. The Psoriasis Area Severity Index score was significantly lower than that of the IMQ group. Flow cytometry analysis indicated that cornuside effectively inhibited Th1- and Th17-cell infiltration and promoted aggregation of Th2 cells in skin tissues. Cornuside also inhibited the infiltration of macrophages to the skin. Furthermore, in-vitro experiments indicated that cornuside also decreased the polarization of M1 macrophages and reduced the levels of associated cytokines. Western blotting demonstrated that cornuside suppressed the phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular receptor kinase (ERK) in bone marrow-derived macrophages. Our findings indicate that cornuside has a protective effect against IMQ-induced psoriasis by inhibiting M1 macrophage polarization through the ERK and JNK signaling pathways and modulating the infiltration of immune cells as well as the expression of inflammatory factors.

Beta-adrenergic signaling and T-lymphocyte-produced catecholamines are necessary for interleukin 17A synthesis

Background

Post-traumatic stress disorder (PTSD) is a debilitating psychological disorder that also presents with neuroimmune irregularities. Patients display elevated sympathetic tone and are at an increased risk of developing secondary autoimmune diseases. Previously, using a preclinical model of PTSD, we demonstrated that elimination of sympathetic signaling to T-lymphocytes specifically limited their ability to produce pro-inflammatory interleukin 17A (IL-17A); a cytokine implicated in the development of many autoimmune disorders. However, the mechanism linking sympathetic signaling to T-lymphocyte IL-17A production remained unclear.

Methods

Using a modified version of repeated social defeat stress (RSDS) that allows for both males and females, we assessed the impact of adrenergic receptor blockade (genetically and pharmacologically) and catecholamine depletion on T-lymphocyte IL-17A generation. Additionally, we explored the impact of adrenergic signaling and T-lymphocyte-produced catecholamines on both CD4+ and CD8+ T-lymphocytes polarized to IL-17A-producing phenotypes ex vivo.

Results

Only pharmacological inhibition of the beta 1 and 2 adrenergic receptors (β1/2) significantly decreased circulating IL-17A levels after RSDS, but did not impact other pro-inflammatory cytokines (e.g., IL-6, TNF-α, and IL-10). This finding was confirmed using RSDS with both global β1/2 receptor knock-out mice, as well as by adoptively transferring β1/2 knock-out T-lymphocytes into immunodeficient hosts. Furthermore, ex vivo polarized T-lymphocytes produced significantly less IL-17A with the blockade of β1/2 signaling, even in the absence of exogenous sympathetic neurotransmitter supplementation, which suggested T-lymphocyte-produced catecholamines may be involved in IL-17A production. Indeed, pharmacological depletion of catecholamines both in vivo and ex vivo abrogated T-lymphocyte IL-17A production demonstrating the importance of immune-generated neurotransmission in pro-inflammatory cytokine generation.

Conclusions

Our data depict a novel role for β1/2 adrenergic receptors and autologous catecholamine signaling during T-lymphocyte IL-17A production. These findings provide a new target for pharmacological therapy in both psychiatric and autoimmune diseases associated with IL-17A-related pathology.

Unveiling the role of IL-17: Therapeutic insights and cardiovascular implications

Interleukin-17 (IL-17), a pivotal cytokine in immune regulation, has attracted significant attention in recent years due to its roles in various physiological and pathological processes. This review explores IL-17 in immunological context, emphasizing its structure, production, and signaling pathways. Specifically, we explore its involvement in inflammatory diseases and autoimmune diseases, with a notable focus on its emerging implications in cardiovascular system. Through an array of research insights, IL-17 displays multifaceted functions yet awaiting comprehensive discovery. Highlighting therapeutic avenues, we scrutinize the efficacy and clinical application of four marketed IL-17 mAbs along other targeted therapies, emphasizing their potential in immune-mediated disease management. Additionally, we discussed the novel IL-17D-CD93 axis, elucidating recent breakthroughs in their biological function and clinical implications, inviting prospects for transformative advancements in immunology and beyond.

LC-MS-based rheumatoid arthritis serum metabolomics reveals the role of deoxyinosine in attenuating collagen-induced arthritis in mice

Rheumatoid arthritis (RA) is a persistent autoimmune condition with no identified cure currently. Recently, scientists have applied metabolomics to investigate altered metabolic profiles and unique diseases-associated metabolic signatures. Herein, we applied metabolomics approach to analyze serum samples of 41 RA patients and 42 healthy controls (HC) with the aim to characterize RA patients' metabolic profile, investigate related underlying pathological processes, and identify target metabolites. By utilizing ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry, we found 168 proposed metabolites and 45 vital metabolic pathways. Our analysis revealed that deoxyinosine (DI), a metabolite of the purine metabolic pathway, was the most significant reduced metabolite in RA patients. Furthermore, through targeted detection, we confirmed lower concentration of DI in RA patients' peripheral blood. Moreover, DI inhibited lipopolysaccharide-induced inflammation both in vitro and in vivo. We further assessed DI's therapeutic potential in a collagen-induced arthritis (CIA) murine model. The results revealed that DI attenuated CIA, as evidenced by significantly lowered clinical scores of arthritis, alleviated joint swelling, and mitigated bone destruction. Moreover, we elucidated the underlying mechanism by which DI increased the population of myeloid-derived suppressor cells (MDSCs) and suppressed the proliferation of induced T cells. Collectively, these findings suggested that DI potentially ameliorated RA by inducing immunosuppressive MDSCs. The study provides key observations on RA pathogenesis and may contribute to developing novel therapeutic strategies for this debilitating condition.

Research on the role and mechanism of IL-17 in intervertebral disc degeneration

Intervertebral disc degeneration (IDD) is one of the primary causes of low back pain (LBP), which seriously affects patients' quality of life. In recent years, interleukin (IL)-17 has been shown to be highly expressed in the intervertebral disc (IVD) tissues and serum of patients with IDD, and IL-17A has been shown to promote IDD through multiple pathways. We first searched databases such as PubMed, Cochrane, Embase, and Web of Science using the search terms "IL-17 or interleukin 17″ and "intervertebral discs". The search period ranged from the inception of the databases to December 2023. A total of 24 articles were selected after full-text screening. The main conclusion of the clinical studies was that IL-17A levels are significantly increased in the IVD tissues and serum of IDD patients. The results from the in vitro studies indicated that IL-17A can activate signaling pathways such as the NF-κB and MAPK pathways; promote inflammatory responses, extracellular matrix degradation, and angiogenesis; and inhibit autophagy in nucleus pulposus cells. The main finding of the in vivo experiments was that puncture of animal IVDs resulted in elevated levels of IL-17A within the IVD, thereby inducing IDD. Clinical studies, in vitro experiments, and in vivo experiments confirmed that IL-17A is closely related to IDD. Therefore, drugs that target IL-17A may be novel treatments for IDD, providing a new theoretical basis for IDD therapy.

Assessing the Causal Relationship between Genetically Determined Inflammatory Cytokines and Parkinson's Disease Risk: A Bidirectional Two-Sample Mendelian Randomization Study

Background

Observational studies have suggested an association between inflammatory cytokines and Parkinson's disease (PD). This Mendelian randomization (MR) was conducted to further assess the causal correlations between inflammatory cytokines and PD.

Methods

Genetic instruments associated with inflammatory cytokines were extracted from a large summary genome-wide association studies (GWAS) involving 8,293 European participants. Summary-level statistics for PD were obtained from a large-sample GWAS containing 17 studies that involved European participants. Causalities of exposures and outcomes were explored mainly using inverse variance weighted (IVW) method.

Results

The IVW method indicated that basic fibroblast growth factor (FGFBasic), interleukin-2 (IL-2), and macrophage migration inhibitory factor (MIF) may be suggestively associated with the risk of PD (OR: 0.71, 95%CI: 0.52-0.96, P = 0.027; OR: 1.18, 95%CI: 1.01-1.38, P = 0.041; and OR: 1.23, 95%CI: 1.04-1.46, P = 0.018). In the reverse direction, monokine induced by interferon gamma (MIG), beta nerve growth factor (bNGF), interleukin-17 (IL-17), and interferon gamma (IFNg) are suggested to be the consequences of PD.

Conclusion

Our MR analysis indicated that suggestive associations between circulating levels of FGFBasic, IL-2, and MIF and PD risk. In addition, MIG, bNGF, IL-17, and IFNg are more likely to be involved in the development of downstream PD.

IL-17 promotes osteoclast-induced bone loss by regulating glutamine-dependent energy metabolism

Osteoclasts consume an amount of adenosine triphosphate (ATP) to perform their bone resorption function in the development of osteoporosis. However, the mechanism underlying osteoclast energy metabolism has not been fully elucidated. In addition to glucose, glutamine (Glu) is another major energy carrier to produce ATP. However, the role of Glu metabolism in osteoclasts and the related molecular mechanisms has been poorly elucidated. Here we show that Glu is required for osteoclast differentiation and function, and that Glu deprivation or pharmacological inhibition of Glu transporter ASCT2 by V9302 suppresses osteoclast differentiation and their bone resorptive function. In vivo treatment with V9302 improved OVX-induced bone loss. Mechanistically, RNA-seq combined with in vitro and in vivo experiments suggested that Glu mediates the role of IL-17 in promoting osteoclast differentiation and in regulating energy metabolism. In vivo IL-17 treatment exacerbated OVX-induced bone loss, and this effect requires the participation of Glu or its downstream metabolite α-KG. Taken together, this study revealed a previously unappreciated regulation of IL-17 on energy metabolism, and this regulation is Glu-dependent. Targeting the IL-17-Glu-energy metabolism axis may be a potential therapeutic strategy for the treatment of osteoporosis and other IL-17 related diseases.

Immunomodulatory effect of vitamin D supplementation on Behçet's disease patients: effect on nitric oxide and Th17/Treg cytokines production

INTRODUCTION

In the last decade, an immuno-modulatory effect of vitamin D supplementation have emerged as a potential therapeutic approach for some inflammatory and autoimmune diseases. As previously reported, vitamin D deficiency was strongly linked to several diseases as Behçet's disease (BD). BD is a chronic systemic inflammatory disorder with autoimmunity, genetic and environmental factors involvement. The aim of our current study is to set up a new therapeutic strategy in BD, combining conventional therapy and vitamin D supplementation.

MATERIALS AND METHODS

Blood samples were collected from active and inactive BD patients and healthy controls (HC) to evaluate 25(OH) vitamin D levels using an electrochemiluminescence method. All deficient and insufficient vitamin D BD patients' were supplemented with vitamin D3 (CHOLECALCIFEROL, 200 000 UI/1 ml). In this context, NO, IL-17A and IL-10 levels were evaluated in patients and HC in vivo and ex vivo using Griess and ELISA methods respectively.

RESULTS

Before supplementation, we noted with interest that BD patients had vitamin D deficiency, associated with elevated in vivo and ex vivo NO and IL-17A levels compared to HC. Conversely, low IL-10 levels were observed in the same BD patients in comparison to HC. Interestingly, restored vitamin D status in supplemented BD patients was related to the decreased NO levels. In the same way, the IL-10/IL-17A ratio was improved.

CONCLUSIONS

Collectively, our data suggest that vitamin D supplementation in combination with conventional treatments has a beneficial effect and could constitute a good therapeutic candidate for alleviating inflammatory responses during Behçet disease.

Exploring the mechanism of Celastrol in the treatment of rheumatoid arthritis based on systems pharmacology and multi-omics

To explore the molecular network mechanism of Celastrol in the treatment of rheumatoid arthritis (RA) based on a novel strategy (integrated systems pharmacology, proteomics, transcriptomics and single-cell transcriptomics). Firstly, the potential targets of Celastrol and RA genes were predicted through the database, and the Celastrol-RA targets were obtained by taking the intersection. Then, transcriptomic data and proteomic data of Celastrol treatment of RA were collected. Subsequently, Celastrol-RA targets, differentially expressed genes, and differentially expressed proteins were imported into Metascape for enrichment analysis, and related networks were constructed. Finally, the core targets of Celastrol-RA targets, differentially expressed genes, and differentially expressed proteins were mapped to synoviocytes of RA mice to find potential cell populations for Celastrol therapy. A total of 195 Celastrol-RA targets, 2068 differential genes, 294 differential proteins were obtained. The results of enrichment analysis showed that these targets, genes and proteins were mainly related to extracellular matrix organization, TGF-β signaling pathway, etc. The results of single cell sequencing showed that the main clusters of these targets, genes, and proteins could be mapped to RA synovial cells. For example, Mmp9 was mainly distributed in Hematopoietic cells, especially in Ptprn+fibroblast. The results of molecular docking also suggested that Celastrol could stably combine with molecules predicted by network pharmacology. In conclusion, this study used systems pharmacology, transcriptomics, proteomics, single-cell transcriptomics to reveal that Celastrol may regulate the PI3K/AKT signaling pathway by regulating key targets such as TNF and IL6, and then play an immune regulatory role.

Secukinumab in the treatment of hidradenitis suppurativa

The IL-17 pathways are involved in the pathophysiology of many inflammatory skin conditions, including hidradenitis suppurativa. Secukinumab, an IL-17A inhibitor, has been used for years in inflammatory skin disorders such as psoriasis. To date, the only US FDA-approved medication for hidradenitis suppurativa is adalimumab, a TNF-α inhibitor. Recently, secukinumab has demonstrated promising results in the treatment of hidradenitis suppurativa in the phase III SUNSHINE and SUNRISE clinical trials. This article reviews the mechanism of action of secukinumab and summarizes the available clinical efficacy and safety data regarding secukinumab in the management of hidradenitis suppurativa.

Chemerin and IL-17 are potential predictors and Chemerin silencing alleviates inflammatory response and bone remodeling in chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is an inflammatory disease of paranasal sinuses. This study is formulated to explore the roles of pro-inflammatory factors Chemerin and interleukin-17 (IL-17) in CRS. Patients suffering from CRS without/with nasal polyps (CRSsNP/CRSwNP), along with volunteers, were recruited. CRS rabbit models were constructed by Staphylococcus aureus infection and rabbits were injected with lentiviral vectors of short hairpin RNA-targeting Chemerin (shChemerin), followed by micro-computed tomography (CT) scan. Levels of Chemerin and IL-17 were determined, and histopathological lesions were observed in subjects and CRS rabbits. Correlations between Chemerin/IL-17 level and Lund-Mackay/Lund-Kennedy scores of subjects and the predictive value of Chemerin or IL-17 for CRS were analyzed. In CRS patients and rabbits, inflammatory degrees and the level of Chemerin/IL-17 were increased in pathological tissues or plasma, while Chemerin silencing alleviated CRS symptoms of CRS rabbits. Chemerin and IL-17 were mainly located in the immune cells of pathological tissues and presented the positive correlation with Lund-Mackay/Lund-Kennedy score of CRS patients. Also, they showed high predictive value for CRS. Micro-CT scan uncovered that CRS rabbits had increased bone remodeling, which was alleviated by Chemerin silencing. Collectively, Chemerin and IL-17 are potential predictors and Chemerin silencing alleviates inflammatory response and bone remodeling in chronic rhinosinusitis.

Genetic association between interleukin-17 and susceptibility to rheumatoid arthritis

BACKGROUND

The pathogenesis of rheumatoid arthritis (RA) is an immune imbalance, in which various inflammatory immune cells and pro-inflammatory factors are involved. Interleukin-17 (IL-17), a potent pro-inflammatory cytokine, has been found to have increased expression in the joints of patients with RA compared to healthy individuals. However, the causal relationship between the expression level of IL-17 or IL-17 receptor (IL-17R) and RA remained unknown. In this study, two-sample Mendelian randomization (MR) was used to investigate the causal relationship between IL-17 and RA.

METHODS

Summary statistics for RA (14,361 RA cases and 43,923 healthy controls) and IL-17 (3,301 samples) were obtained from an available meta-analysis of published genome-wide association studies (GWAS). Relevant single nucleotide polymorphisms (SNPs) were selected by executing quality control steps from the GWAS summary results. Then we used bi-directional two-sample Mendelian randomization (MR) and multi-variable MR (MVMR) analysis to examine evidence of causality. MR and MVMR analyses progressed mainly using inverse variance weighted (IVW), weighted median (WM), and MR-Egger regression methods, which were applied to the genetic instrumental variables (IVs) of IL-17A/IL-17 RA, IL-17C/IL-17 RC, and IL-17D/IL-17RD and RA. For assessing the robustness of the results, we also carried out a sensitivity analysis to assess heterogeneity and pleiotropy, such as MR-Egger, leave-one-out, and MR pleiotropy residual sum and outlier (MR-PRESSO).

RESULTS

Two-sample MR Analysis showed the causal relationship between IL-17A/IL-17RA and RA. The presence of genetically high IL-17A/IL-17RA may increase the risk of RA (IL-17A(OR = 1.095; 95% C.I., 0.990-1.210, p.adj = 0.013), IL-17RA(OR = 1.113, 95%CI = 1.006-1.231, p.adj = 0.006)). However, the results indicated that IL-17C/IL-17RC, and IL-17D/IL-17RD demonstrated no causal impact on RA (IL-17C(OR = 1.007, 95%CI = 0.890-1.139, p.adj = 0.152), IL-17RC(OR = 1.006, 95%CI = 0.904-1.119, p.adj = 0.152), IL-17D(OR = 0.979, 95%CI = 0.843-1.137, p.adj = 0.130), IL-17RD(OR = 0.983, 95%CI = 0.876-1.104, p.adj = 0.129)). Furthermore, MVMR analysis shown that IL-17RA(OR = 1.049, 95% CI: 0.997-1.102, p.adj = 0.014) was associated with increased risk of RA. Sensitivity analysis showed no heterogeneity and pleiotropy, suggesting that the above results were robust and reliable.

CONCLUSION

The MR analysis provides evidence that IL-17A/IL-17RA are risk factors for RA. This emphasizes the importance of intervention on IL-17A/IL-17RA in patients with RA. Developing drugs that limit IL-17A may reduce the risk of RA.

Single-cell transcriptomics reveals prominent expression of IL-14, IL-18, and IL-32 in psoriasis

RATIONALE

Psoriasis is a chronic inflammatory skin disease involving different cytokines and chemokines.

OBJECTIVES

Here we use single-cell transcriptomic analyses to identify relevant immune cell and nonimmune cell populations for an in-depth characterization of cell types and inflammatory mediators in this disease.

METHODS

Psoriasis skin lesions of eight patients are analyzed using single-cell technology. Data are further validated by in situ hybridization (ISH) of human tissues, serum analyses of human samples and tissues of a murine model of psoriasis, and by in vitro cell culture experiments.

RESULTS

Several different immune-activated cell types with particular cytokine patterns are identified such as keratinocytes, T-helper cells, dendritic cells, macrophages, and fibroblasts. Apart from well-known factors, IL-14 (TXLNA), IL-18, and IL-32 are identified with prominent expression in individual cell types in psoriasis. The percentage of inflammatory cellular subtypes expressing IL-14, IL-18, and IL-32 was significantly higher in psoriatic skin compared with healthy control skin. These findings were confirmed by ISH of human skin samples, in a murine model of psoriasis, in human serum samples, and in in vitro experiments.

CONCLUSIONS

Taken together, we provide a differentiated view of psoriasis immune-cell phenotypes that support the role of IL-14, IL-18, and IL-32 in psoriasis pathogenesis.

New biologic (Ab-IPL-IL-17) for IL-17-mediated diseases: identification of the bioactive sequence (nIL-17) for IL-17A/F function

OBJECTIVES

Interleukin (IL) 17s cytokines are key drivers of inflammation that are functionally dysregulated in several human immune-mediated inflammatory diseases (IMIDs), such as rheumatoid arthritis (RA), psoriasis and inflammatory bowel disease (IBD). Targeting these cytokines has some therapeutic benefits, but issues associated with low therapeutic efficacy and immunogenicity for subgroups of patients or IMIDs reduce their clinical use. Therefore, there is an urgent need to improve the coverage and efficacy of antibodies targeting IL-17A and/or IL-17F and IL-17A/F heterodimer.

METHODS AND RESULTS

Here, we initially identified a bioactive 20 amino acid IL-17A/F-derived peptide (nIL-17) that mimics the pro-inflammatory actions of the full-length proteins. Subsequently, we generated a novel anti-IL-17 neutralising monoclonal antibody (Ab-IPL-IL-17) capable of effectively reversing the pro-inflammatory, pro-migratory actions of both nIL-17 and IL-17A/F. Importantly, we demonstrated that Ab-IPL-IL-17 has less off-target effects than the current gold-standard biologic, secukinumab. Finally, we compared the therapeutic efficacy of Ab-IPL-IL-17 with reference anti-IL-17 antibodies in preclinical murine models and samples from patients with RA and IBD. We found that Ab-IPL-IL-17 could effectively reduce clinical signs of arthritis and neutralise elevated IL-17 levels in IBD patient serum.

CONCLUSIONS

Collectively, our preclinical and in vitro clinical evidence indicates high efficacy and therapeutic potency of Ab-IPL-IL-17, supporting the rationale for large-scale clinical evaluation of Ab-IPL-IL-17 in patients with IMIDs.

Risk of candidiasis associated with interleukin-17 inhibitors: Implications and management

The application of interleukin-17 (IL-17) inhibitors, including secukinumab, ixekizumab, brodalumab, and bimekizumab, are associated with elevated risk of candidiasis. These medications interfere with the IL-17 pathway, which is essential for maintaining mucosal barriers and coordinating the immune response against Candida species. The observational data and clinical trials demonstrate the increased incidence of candidiasis in individuals treated with IL-17 inhibitors. Brodalumab and bimekizumab pose a greater risk than secukinumab in eliciting candidiasis, whereas the data regarding ixekizumab are equivocal. Higher doses and prolonged treatment duration of IL-17 inhibitors increase the risk of candidiasis by compromising the immune response against Candida species. Prior to prescribing IL-17 inhibitors, healthcare professionals should comprehensively evaluate patients' medical histories and assess their risk factors. Patients should be educated on the signs and symptoms of candidiasis to facilitate early detection and intervention. Future research should focus on identifying the risk factors associated with candidiasis in patients receiving IL-17 inhibitors. Prospective studies and long-term surveillance are required to explore the impact of specific inhibitors on the incidence and severity of candidiasis and to evaluate the effectiveness of combination therapies, such as concurrent use of IL-17 inhibitors and prophylactic antifungal agents.

The IL-17 family in diseases: from bench to bedside

The interleukin-17 (IL-17) family comprises six members (IL-17A-17F), and recently, all of its related receptors have been discovered. IL-17 was first discovered approximately 30 years ago. Members of this family have various biological functions, including driving an inflammatory cascade during infections and autoimmune diseases, as well as boosting protective immunity against various pathogens. IL-17 is a highly versatile proinflammatory cytokine necessary for vital processes including host immune defenses, tissue repair, inflammatory disease pathogenesis, and cancer progression. However, how IL-17 performs these functions remains controversial. The multifunctional properties of IL-17 have attracted research interest, and emerging data have gradually improved our understanding of the IL-17 signaling pathway. However, a comprehensive review is required to understand its role in both host defense functions and pathogenesis in the body. This review can aid researchers in better understanding the mechanisms underlying IL-17's roles in vivo and provide a theoretical basis for future studies aiming to regulate IL-17 expression and function. This review discusses recent progress in understanding the IL-17 signaling pathway and its physiological roles. In addition, we present the mechanism underlying IL-17's role in various pathologies, particularly, in IL-17-induced systemic lupus erythematosus and IL-17-related tumor cell transformation and metastasis. In addition, we have briefly discussed promising developments in the diagnosis and treatment of autoimmune diseases and tumors.

The pathogenetic role of Th17 immune response in atopic dermatitis

PURPOSE OF REVIEW

As we continue to unravel the pathophysiology and immune mechanisms underlying atopic dermatitis (AD), the emergence of targeted treatments has provided new options for management. Although there are available therapies targeting various immune pathways in AD, the precise pathogenic role of interleukin (IL)-17 in AD pathogenesis remains unclear. The objective of this review is to examine the existing data pertaining to the role of IL-17 in AD and shed light on the potential of targeting this pathway as a therapeutic approach in AD treatment.

RECENT FINDINGS

IL-17 has a dual role of pro-inflammatory and immune protective function, making it an important player in several autoimmune and inflammatory conditions. The extent of IL-17 axis involvement in AD pathogenesis is still debatable. Emerging data show that Th17-related cytokines/chemokines are elevated in skin and sera samples of AD patients, with some articles reporting correlations with disease severity. Particularly increased Th17 signature in specific AD patient subsets, such as Asian-origin or pediatric patients, suggests that certain patients' disease presentations are more predominantly influenced by Th17, and, thus, they may benefit more from Th17 therapeutic targeting approaches. Lack of clinical efficacy with anti-Th17 biologics in AD patients, underscores the need to better elucidate the role of Th17 in AD pathogenesis, along with its utility in therapy.

SUMMARY

The well established role of IL-17 in autoimmune disorders hints for its possible participation in AD disease pathogenesis. Subsequent investigations are needed to assess whether the targeting of specific IL-17 isoforms, homodimers, or heterodimers in specific subpopulations of AD can modify treatment outcomes.

Assessing causal relationship between circulating cytokines and age-related neurodegenerative diseases: a bidirectional two-sample Mendelian randomization analysis

Numerous studies have reported that circulating cytokines (CCs) are linked to age-related neurodegenerative diseases (ANDDs); however, there is a lack of systematic investigation for the causal association. A two-sample bidirectional Mendelian Randomisation (MR) method was utilized to evaluate the causal effect. We applied genetic variants correlated with concentrations of CCs from a genome-wide association study meta-analysis (n = 8293) as instrumental variables. Summary data of three major ANDDs [Alzheimer's disease (AD), Parkinson's disease (PD), and Amyotrophic lateral sclerosis (ALS)] were identified from the IEU OpenGWAS platform (n = 627, 266). Inverse-variance weighted method is the main approach to analyse causal effect, and MR results are verified by several sensitivity and pleiotropy analyses. In directional MR, it suggested that several CCs were nominally correlated with the risk of ANDDs, with a causal odds ratio (OR) of Interleukin (IL)-5 of 0.909 for AD; OR of IL-2 of 1.169 for PD; and OR of Beta nerve growth factor of 1.142 for ALS). In reverse MR, there were some suggestively causal effects of ANDDs on CCs (AD on increased Basic fibroblast growth factor and IL-12 and decreased Stem cell growth factor beta; PD on decreased Monokine induced by interferon-gamma; ALS on decreased Basic fibroblast growth factor and IL-17). The findings were stable across sensitivity and pleiotropy analyses. However, after Bonferroni correction, there is no statistically significant association between CCs and ANDDs. Through the genetic epidemiological approach, our study assessed the role and presented possible causal associations between CCs and ANDDs. Further studies are warranted to verify the causal associations.

Clinical significance of Interleukin 17 receptor E in diabetic nephropathy

OBJECTIVE

Diabetic nephropathy (DN) is a leading cause of end-stage renal disease. Since there are limited therapeutic options available for the prevention of DN progression, it is imperative to explore novel differentially expressed genes and therapeutic targets for DN.

METHODS

In this study, mice kidney tissue were subjected to transcriptome sequencing and the results were analysed using bioinformatics methods. Interleukin 17 receptor E (IL-17RE) was screened from the sequencing data and its expression was validated in the animal tissues and a cross-sectional clinical study. Fifty-five DN patients were enrolled and further subdivided into two groups based on the urinary albumin-to-creatinine ratio (UACR). Two control groups were used for comparison (minimal change disease group, 12 patients; normal control group, 6 patients). Correlation analysis was conducted to study the relationship between IL-17RE expression and the clinicopathological indices. Logistic regression and receiver operating characteristic (ROC) curve analyses were conducted to evaluate the diagnostic value.

RESULTS

IL-17RE expression was significantly higher in db/db mice and the kidney tissues of DN patients than the control group. IL-17RE protein levels in the kidney tissues were strongly correlated with neutrophil gelatinase-associated lipocalin (NGAL) levels, UACR, and certain clinicopathological indices. IL-17RE levels, total cholesterol (TC) levels, and glomerular lesions were independent risk factors for macroalbuminuria. ROC curves showed a good detection value for IL-17RE in macroalbuminuria (area under the curve = 0.861).

CONCLUSION

The results of this study provide novel insights into DN pathogenesis. Kidney IL-17RE expression levels were associated with DN disease severity and albuminuria.

The role of IL-17 in acute kidney injury

Acute kidney injury (AKI) is a common clinical kidney disease with a high mortality rate. AKI is caused by a variety of factors, including sepsis, ischemia, and nephrotoxic drugs, and can progress to chronic kidney disease and end-stage renal disease. Numerous studies have suggested that cytokines can be used as therapeutic targets for AKI. IL-17 is a pro-inflammatory cytokine that not only participates in the host defense and the development of autoimmune diseases but also is linked to AKI due to a variety of factors. This review will give an overview of the structure, signaling pathways, and biological functions of IL-17, as well as its role in AKI, to show that IL-17 is a potential target for the prevention and treatment of AKI.

Imatinib mitigates experimentally-induced ulcerative colitis: Possible contribution of NF-kB/JAK2/STAT3/COX2 signaling pathway

RATIONALE

Ulcerative colitis (UC) is a chronic immune-mediated disease characterized by recurrent inflammation, damage, and alteration of the large intestine's mucosal and submucosal surfaces. The purpose of this research was to evaluate the impact of tyrosine kinase inhibitor (imatinib) on experimentally induced UC in rats via acetic acid (AA).

METHODS

Male rats were randomly assigned to four groups: control, AA, AA + imatinib (10 mg/kg), and AA + imatinib (20 mg/kg). Imatinib (10 and 20 mg/kg/day) was orally supplied by oral syringe for one week before induction of UC. On the eighth day, Rats received enemas containing a 4 % solution of acetic acid to induce colitis. One day after inducing colitis, rats were euthanized and their colons were subjected to morphological, biochemical, histological, and immunohistochemical analysis.

RESULTS

Imatinib pretreatment significantly decreased macroscopic and histological damage scores, decreased disease activity index as well as colon mass index. In addition, imatinib successfully lowered the levels of malondialdehyde (MDA) in colonic tissues and enhanced superoxide dismutase activity (SOD) and glutathione content (GSH). Imatinib also reduced colonic levels of inflammatory interleukins (IL-23, IL-17, IL-6), JAK2 and STAT3. Furthermore, imatinib suppressed nuclear transcription factor kappa B (NF-kB/p65) level, and COX2 expression in colonic tissues.

SIGNIFICANCE

Imatinib may be a viable therapy option for UC as it halts the interaction network of NF-kB/JAK2/STAT3/COX2 signaling pathway.