Role of the IL-23/IL-17 Pathway in Rheumatic Diseases: An Overview

In vitro identification of single-stranded DNA aptamers targeting human IL-23 using the protein-SELEX strategy

Interleukin (IL)-23 inhibitor monoclonal antibodies shown significant efficacy in treating autoimmune diseases. DNA or RNA aptamers exhibit comparable specificity to antibodies, are cost-effective, non-immunogenic, and do not have batch to batch variation. This study aimed to characterize a single-stranded DNA (ssDNA) aptamer targeting human IL-23. The alpha subunit of IL-23 (P19) and intact IL-23 were cloned, expressed, and the proteins finally were purified through Ni2+-iminodiacetic acid affinity chromatography. The selection and characterization of ssDNA aptamer against P19 were conducted using the protein-systematic evolution of ligands by exponential enrichment (SELEX). Dot blot assay was carried out to monitor binding of the aptamer output of SELEX rounds, to P19 protein. The dissociation constant (Kd) of aptamers with positive results in dot blot assay, determined based on their binding to IL-23 using an ELISA method. Recombinant P19 and IL-23 proteins were 26 and 72 kDa, respectively, observed on SDS-PAGE .12 %. The aptamers output from 7, 8, 9, 10, 11, and 12 rounds of the SELEX was monitored by dot blot assay, revealing that the aptamer from the round 8 has stronger luminescent signal and was selected for TA-cloning. After analyzing the biotinylated aptamers from clones, positive clones in dot blot assay and ELISA were sequenced. Finally, the Kd calculation revealed three aptamers with high affinity, named A23P3, A23P6, and A23P15 with Kd values of 1.37, 2.139, and 2.88 nM, respectively. Results of this study introduced three specific anti-IL-23 ssDNA aptamers with high affinity, which could be utilized for therapeutic and diagnostic purposes.

Sappanone A ameliorated imiquimod-induced psoriasis-like dermatitis in BALB/c mice via suppressing Mmp8 expression and IL-17 signaling pathway

Psoriasis is a prevalent immune-mediated inflammatory skin disease characterized by excessive abnormal proliferation of keratinocytes and infiltration of immune cells, which have significant impact on the life quality of individuals. Although biological agents and small molecule targeted drugs have brought significant clinical benefits to psoriasis patients, adverse reactions and high prices remains key issues in clinical medication of psoriasis, while natural product monomers possess high efficiency, low toxicity, anti-inflammatory and immunomodulatory properties, and bring new hope for the clinical treatment of psoriasis. Sappanone A (SA), a small molecule compound isolated from Caesalpinia sappan L, exhibits significant anti-inflammatory properties in various models, such as kidney inflammation and LPS-induced mice inflammation. Among these effects, the anti-inflammatory property of SA has received significant attention. In our study, we found that SA exhibited anti-proliferation and anti-inflammatory effects in HaCaT cells, and significantly alleviated imiquimod-induced psoriasis-like skin lesions via the inhibition of the excessive proliferation of keratinocytes and the infiltration of lymphocytes. Furthermore, the combinational analysis of network pharmacology and transcriptome sequencing revealed that SA exerted anti-psoriasis effects by inhibiting the matrix metalloproteinase 8 (Mmp8) expression and IL-17 pathway activation. In summary, we have first demonstrated that SA can be used as a novel anti-psoriasis drug, which may provide a novel strategy for the clinical treatment of psoriasis.

Global research landscape and emerging trends in Graves' disease: A bibliometric analysis

BACKGROUND

Graves' disease is a prevalent thyroid disorder and is the primary cause of hyperthyroidism. Significant progress has been made in understanding the epidemiology, pathogenesis, diagnosis, treatment, and prognosis of this disease. However, bibliometric analyses on Graves' disease are lacking. We aimed to comprehensively summarize the research, progression, and focal points of Graves' disease through data mining and integrated analysis of the existing literature.

METHODS

We retrieved relevant literature on Graves' disease from 2003 to 2023 from the Web of Science database. We performed bibliometric analysis using CiteSpace and the R package Bibliometrix.

RESULTS

We identified 10,901 publications from 132 countries, with a steady rise in the number of publications over the past 5 years. The US leads in publication volume, with the University of California System being the primary contributing institution. The journal Thyroid had the highest publication output, while the Journal of Clinical Endocrinology and Metabolism was the most frequently cited. These publications involved 2305 authors, with Antonelli Alessandro and Smith Terry being the most prolific. The most frequently cited articles were the "2016 American Thyroid Association guidelines for diagnosis and management of hyperthyroidism and other causes of thyrotoxicosis" and the "Thyroid Association/European Group on Graves' orbitopathy guidelines for the management of Graves' orbitopathy." Analysis of the bursts of cited references, keywords, and their clustering revealed that research on Graves' disease predominantly centers on clinical management, thyroid-stimulating hormone receptors, thyroid hormones, autoimmunity and inflammation, Graves' ophthalmopathy, thyroid nodules, and thyroid cancer.

CONCLUSION

This is the first comprehensive bibliometric study to summarize progress and trends in Graves' disease research. These results highlight recent research hotspots and promising directions, thereby providing a valuable reference for other scholars.

Pharmacokinetics, Safety, and Immunogenicity of Intravenous and Subcutaneous Single-Dose QX002N Injection in Healthy Subjects: A Randomized, Open, Parallel, Single-Center, Phase I Study

INTRODUCTION

Interleukin-17A (IL-17A) plays a crucial role in the pathogenesis of ankylosing spondylitis (AS), although not all patients respond to traditional IL-17A antibody treatments. QX002N injection, as a new monoclonal antibody targeting IL-17A, has shown potential in treating AS, offering a new treatment option for patients who do not respond well to existing therapies.

METHODS

A randomized, open, parallel, single-center, phase I study was conducted to assess the pharmacokinetics, safety, and immunogenicity of single doses of QX002N injection administered intravenously (IV) or subcutaneously (SC) to healthy Chinese volunteers. Blood samples were collected at specified time intervals, and then serum concentrations of QX002N were analyzed by enzyme-linked immunosorbent assay.

RESULTS

Pharmacokinetic analysis of the drug concentration-time data showed that the mean maximum observed serum QX002N concentration (Cmax) was 110 and 33.9 µg/ml, respectively. The average area under the drug concentration-time curves from 0 to the time of the last quantifiable concentration (AUClast) were 52,656 and 36,269 µg·h/ml, respectively and the average area under the drug concentration-time curves from 0 to infinity (AUCinf) were 54,867 and 38,194 µg·h/ml, respectively. The absolute bioavailability of QX002N after SC injection was 69.6%.

CONCLUSIONS

Immunogenicity was assessed and all the subjects in this study were Anti-drug antibody (ADA)-negative, which means no subjects appeared to develop immunogenicity to QX002N. All the results testify to the safety of QX002N injection, which is satisfactory after IV or SC dosing in healthy subjects.

TRIAL REGISTRATION

www.chinadrugtirals.org.cn , CTR20220430.

Modulation of Interleukin-23 Signaling With Guselkumab in Biologic-Naive Patients Versus Tumor Necrosis Factor Inhibitor-Inadequate Responders With Active Psoriatic Arthritis

OBJECTIVE

We assessed and compared immunologic differences and associations with clinical response to guselkumab, a fully human interleukin (IL)-23p19 subunit inhibitor, in participants with active psoriatic arthritis (PsA) who were biologic-naive or had inadequate response to tumor necrosis factor inhibitors (TNFi-IR).

METHODS

Serum biomarker levels at baseline and after treatment with guselkumab 100 mg every 8 weeks were compared between biologic-naive (n = 251) and TNFi-IR (n = 93) subgroups identified in the pooled DISCOVER-1/DISCOVER-2/COSMOS data set. Baseline biomarker levels determined by achievement of week 24 clinical responses (≥75%/90% improvement in Psoriasis Area and Severity Index [PASI 75/90], Investigator's Global Assessment [IGA] of psoriasis score 0/1 and ≥2-point improvement], ≥20% improvement in American College of Rheumatology criteria [ACR20]) were compared between prior treatment subgroups.

RESULTS

Baseline IL-22, TNFα, and beta defensin-2 (BD-2) levels were significantly lower in biologic-naive than in TNFi-IR participants. With guselkumab, week 24 IL-17A, IL-17F, IL-22, serum amyloid A, C-reactive protein, IL-6, and BD-2 levels were significantly reduced from baseline in biologic-naive and TNFi-IR participants (≥1.4-fold difference, nominal P < 0.05). Clinical responders to guselkumab exhibited significantly higher baseline levels of several biomarkers than nonresponders (IL-17A, IL-17F, BD-2 in biologic-naive PASI 90 responders; IL-17A, BD-2 in TNFi-IR IGA 0/1 responders; IL-22, BD-2 in TNFi-IR PASI 90 responders [nominal P < 0.05]) and trended higher in TNFi-IR ACR20 responders.

CONCLUSION

Guselkumab modulates IL-23 signaling and provides consistent pharmacodynamic effects in both biologic-naive and TNFi-IR PsA patients. Significantly elevated baseline IL-22, TNFα, and BD-2 levels and associations between baseline IL-22, IL-17A, and BD-2 levels and skin responses to guselkumab suggest greater dysregulation of IL-23/Th17 signaling in patients with TNFi-IR.

Molecular insights of Eucalyptol (1,8-Cineole) as an anti-arthritic agent: in vivo and in silico analysis of IL-17, IL-10, NF-κB, 5-LOX and COX-2

The monoterpene oxide, Eucalyptol (1,8-Cineole), a primary component of eucalyptus oil, has been evaluated pharmacologically for anti-inflammatory and analgesic activity. Current research aimed to evaluate Eucalyptol's anti-arthritic potential in a Complete Freund's adjuvant induced arthritis that resembles human rheumatoid arthritis. Polyarthritis developed after 0.1 mL CFA injection into the left hind footpad in rats. Oral administration of Eucalyptol at various doses (100, 200 and 400 mg/kg) significantly reduced paw edema, body weight loss, 5-LOX, PGE2 and Anti-CCP levels. Real-time PCR investigation showed significant downregulation of COX-2, TNF-α, NF-κB, IL-17, IL-6, IL-1β and upregulation of IL-4 and IL-10 in Eucalyptol treated groups. Hemoglobin and RBCs counts significantly increased post-treatment with Eucalyptol while ESR, CRP, WBCs and platelets count significantly decreased. Eucalyptol significantly increased Superoxide Dismutase, Catalase and Glutathione levels compared to CFA-induced arthritic control however, MDA significantly decreased post-treatment. Further, radiographic and histopathological examination of the ankle joints of rodents administered Eucalyptol revealed an improvement in the structure of the joints. Piroxicam was taken as standard. Furthermore, molecular docking findings supported the anti-arthritic efficacy of Eucalyptol exhibited high binding interaction against IL-17, TNF-α, IL-4, IL-10, iNOS NF-κB, 5-LOX, and COX-2. Eucalyptol has reduced the severity of CFA induced arthritis by promoting anti-inflammatory cytokines for example IL-4, IL-10 and by inhibiting pro-inflammatory cytokines such as 5-LOX, COX-2, IL-17, NF-κB, TNF-α, IL-6 and IL-1β. Therefore, Eucalyptol might be as a potential therapeutic agent because of its pronounced anti-oxidant and anti-arthritic activity.

IL-17 in wound repair: bridging acute and chronic responses

Chronic wounds, resulting from persistent inflammation, can trigger a cascade of detrimental effects including exacerbating inflammatory cytokines, compromised blood circulation at the wound site, elevation of white blood cell count, increased reactive oxygen species, and the potential risk of bacterial infection. The interleukin-17 (IL-17) signaling pathway, which plays a crucial role in regulating immune responses, has been identified as a promising target for treating inflammatory skin diseases. This review aims to delve deeper into the potential pathological role and molecular mechanisms of the IL-17 family and its pathways in wound repair. The intricate interactions between IL-17 and other cytokines will be discussed in detail, along with the activation of various signaling pathways, to provide a comprehensive understanding of IL-17's involvement in chronic wound inflammation and repair.

Dual-mRNA Delivery Using Tumor Cell Lysate-Based Multifunctional Nanoparticles as an Efficient Colon Cancer Immunogene Therapy

Background

Messenger RNA (mRNA)-based immunogene therapy holds significant promise as an emerging tumor therapy approach. However, the delivery efficiency of existing mRNA methods and their effectiveness in stimulating anti-tumor immune responses require further enhancement. Tumor cell lysates containing tumor-specific antigens and biomarkers can trigger a stronger immune response to tumors. In addition, strategies involving multiple gene therapies offer potential optimization paths for tumor gene treatments.

Methods

Based on the previously developed ideal mRNA delivery system called DOTAP-mPEG-PCL (DMP), which was formed through the self-assembly of 1.2-dioleoyl-3-trimethylammonium-propane (DOTAP) and methoxypoly (ethylene glycol)-b-poly (ε-caprolactone) (mPEG-PCL), we introduced a fused cell-penetrating peptide (fCPP) into the framework and encapsulated tumor cell lysates to form a novel nanovector, termed CLSV system (CLS: CT26 tumor cell lysate, V: nanovector). This system served a dual purpose of facilitating the delivery of two mRNAs and enhancing tumor immunogene therapy through tumor cell lysates.

Results

The synthesized CLSV system had an average size of 241.17 nm and a potential of 39.53 mV. The CLSV system could not only encapsulate tumor cell lysates, but also deliver two mRNAs to tumor cells simultaneously, with a transfection efficiency of up to 60%. The CLSV system effectively activated the immune system such as dendritic cells to mature and activate, leading to an anti-tumor immune response. By loading Bim-encoded mRNA and IL-23A-encoded mRNA, CLSV/Bim and CLSV/IL-23A complexes were formed, respectively, to further induce apoptosis and anti-tumor immunity. The prepared CLSV/dual-mRNA complex showed significant anti-cancer effects in multiple CT26 mouse models.

Conclusion

Our results suggest that the prepared CLSV system is an ideal delivery system for dual-mRNA immunogene therapy.

Review: A Contemporary, Multifaced Insight into Psoriasis Pathogenesis

Psoriasis is a chronic recurrent inflammatory autoimmune pathology with a significant genetic component and several interferences of immunological cells and their cytokines. The complex orchestration of psoriasis pathogenesis is related to the synergic effect of immune cells, polygenic alterations, autoantigens, and several other external factors. The major act of the IL-23/IL-17 axis, strongly influencing the inflammatory pattern established during the disease activity, is visible as a continuous perpetuation of the pro-inflammatory response and keratinocyte activation and proliferation, leading to the development of psoriatic lesions. Genome-wide association studies (GWASs) offer a better view of psoriasis pathogenic pathways, with approximately one-third of psoriasis's genetic impact on psoriasis development associated with the MHC region, with genetic loci located on chromosome 6. The most eloquent genetic factor of psoriasis, PSORS1, was identified in the MHC I site. Among the several factors involved in its complex etiology, dysbiosis, due to genetic or external stimulus, induces a burst of pro-inflammatory consequences; both the cutaneous and gut microbiome get involved in the psoriasis pathogenic process. Cutting-edge research studies and comprehensive insights into psoriasis pathogenesis, fostering novel genetic, epigenetic, and immunological factors, have generated a spectacular improvement over the past decades, securing the path toward a specific and targeted immunotherapeutic approach and delayed progression to inflammatory arthritis. This review aimed to offer insight into various domains that underline the pathogenesis of psoriasis and how they influence disease development and evolution. The pathogenesis mechanism of psoriasis is multifaceted and involves an interplay of cellular and humoral immunity, which affects susceptible microbiota and the genetic background. An in-depth understanding of the role of pathogenic factors forms the basis for developing novel and individualized therapeutic targets that can improve disease management.

The Dysregulated IL-23/TH17 Axis in Endometriosis Pathophysiology

Endometriosis is a chronic inflammatory disease in which endometrial-like tissue grows ectopically, resulting in pelvic pain and infertility. IL-23 is a key contributor in the development and differentiation of TH17 cells, driving TH17 cells toward a pathogenic profile. In a variety of inflammatory and autoimmune disorders, TH17 cells secrete proinflammatory cytokines, including IL-17, contributing to disease pathophysiology. Our studies and others have implicated IL-17 and TH17 cell dysregulation in endometriosis, which is associated with disease severity. In this article, we address whether IL-23-driven TH17 cells contribute to cardinal features of lesion proliferation, vascularization, and inflammation in endometriosis using patient samples, representative cell lines, and our established mouse model of endometriosis. The results indicated dysregulated expression of key genes in the IL-23/TH17 axis in patient ectopic and eutopic endometrial samples and increased IL-23 protein in patient plasma compared with controls. In vitro studies using primary human TH cells determined that rIL-23 mixture treatment increased pathogenic TH17 cell frequency. Similarly, rIL-23 treatment of cell lines (12Z cells, EECCs, HUVECs, and hESCs) representative of the endometriotic lesion microenvironment increased cytokines and growth factors, which play a role in lesion establishment and maintenance. In a syngeneic mouse model of endometriosis, rIL-23 treatment altered numbers of myeloid and T cell subsets in peritoneal fluid and increased giant cells within the lesion. Lesions from rIL-23-treated mice did not reveal significant alterations in proliferation/vascularization, although trends of increased proliferation and vascularization were observed. Collectively, these findings provide insights into the impact of the IL-23/TH17 axis on local immune dysfunction and broadly on endometriosis pathophysiology.

Study of IL-17 and Intercellular Adhesion Molecule-1 in Conjunctivochalasis Using Correlation Analysis

PURPOSE

The aim of this study was to observe the expression of interleukin (IL)-17 and intercellular adhesion molecule (ICAM)-1 in conjunctivochalasis (CCH) and to analyze the correlations between cytokines and the severity of CCH.

METHODS

Serum samples were collected from 22 patients with CCH and 18 normal controls (NCs). The Ocular Surface Disease Index, tear film break-up time, Schirmer I test, and corneal fluorescein staining were used to evaluate the ocular surface signs and symptoms. The concentrations of IL-17, IL-23, and ICAM-1 in serum and cellular supernatants were measured by enzyme-linked immunosorbent assays, and the gene expression levels of cytokines were measured by a quantitative real-time polymerase chain reaction. The relationships between serum concentrations of IL-17, IL-23, and ICAM-1 with clinical ocular surface parameters in CCH were analyzed using the Spearman correlation analysis.

RESULTS

The concentrations of IL-17 and ICAM-1 in serum and cellular supernatants of CCH were significantly higher than those of NCs (all P < 0.001). The concentrations of IL-23 in serum and cellular supernatants of CCH showed no significant difference from those of NCs ( P > 0.05). The mRNA expression levels of IL-17 and ICAM-1 in conjunctival fibroblasts of CCH were significantly higher than those of NCs (all P < 0.001). The mRNA expression of IL-23 in conjunctival fibroblasts of CCH was higher than that of NCs, without a significant difference ( P > 0.05). Furthermore, the serum concentrations of IL-17 and ICAM-1 were positively correlated with Ocular Surface Disease Index and fluorescein staining (all P < 0.05), and negatively correlated with break-up time and Schirmer I test of CCH (all P < 0.05).

CONCLUSIONS

The expression levels of IL-17 and ICAM-1 were significantly increased in CCH serum and associated with the disease severity. We postulate that IL-17 and ICAM-1 may play a role in the pathogenesis of CCH. IL-17 and ICAM-1 antagonists may be a potential treatment option for CCH in the future.

Non-Invasive Assessment of Micro- and Macrovascular Function after Initiation of JAK Inhibitors in Patients with Rheumatoid Arthritis

BACKGROUND

Janus kinase (JAK) inhibitors constitute a novel class of oral biologic disease-modifying antirheumatic drugs for patients with rheumatoid arthritis (RA). However, their use has been associated with increased risk of major cardiovascular events. We investigated whether treatment with JAK inhibitors exerts significant alterations in the micro- and microvasculature in RA patients.

METHODS

Thirteen patients with RA initiating treatment with JAK inhibitors were prospectively studied. Eventually, data from 11 patients who completed the study were analyzed. Procedures were performed at baseline and 3 months after treatment. Nailfold videocapillaroscopy was applied to detect alterations of the dermal capillary network. Participants underwent 24 h ambulatory blood pressure monitoring (Mobil-O-Graph device) for the assessment of blood pressure (both brachial and aortic) and markers of large artery stiffening [pulse wave velocity (PWV), augmentation index] throughout the whole 24 h and the respective day- and nighttime periods. Carotid intima-media thickness was assessed with ultrasound.

RESULTS

Three-month treatment with JAK inhibitors was not associated with any differences in brachial and aortic blood pressure, arterial stiffness, and carotid atherosclerosis, with the only exception of nighttime PWV, which was significantly elevated at follow-up. However, three-month treatment with JAK inhibitors induced significant microvascular alterations and increased the total number of capillaroscopic abnormalities.

CONCLUSIONS

Three-month treatment with JAK inhibitors may exert significant effects on microcirculation as assessed with nailfold videocapillaroscopy, whereas macrovascular structure and function appears largely unaffected. Further research toward this direction may add substantial information to the available literature regarding cardiovascular aspects of JAK inhibitors in RA.

Decoding Tumor Angiogenesis for Therapeutic Advancements: Mechanistic Insights

Tumor angiogenesis, the formation of new blood vessels within the tumor microenvironment, is considered a hallmark of cancer progression and represents a crucial target for therapeutic intervention. The tumor microenvironment is characterized by a complex interplay between proangiogenic and antiangiogenic factors, regulating the vascularization necessary for tumor growth and metastasis. The study of angiogenesis involves a spectrum of techniques, spanning from biomarker assessment to advanced imaging modalities. This comprehensive review aims to provide insights into the molecular intricacies, regulatory dynamics, and clinical implications of tumor angiogenesis. By delving into these aspects, we gain a deeper understanding of the processes driving vascularization in tumors, paving the way for the development of novel and effective antiangiogenic therapies in the fight against cancer.

A GITRL-mTORC1-GM-CSF Positive Loop Promotes Pathogenic Th17 Response in Primary Sjögren Syndrome

OBJECTIVE

Glucocorticoid-induced tumor necrosis factor receptor superfamily-related protein (GITR), with its ligand (GITRL), plays an important role in CD4+ T cell-mediated autoimmunity. This study aimed to investigate the underlying mechanisms of GITRL in primary Sjögren syndrome (pSS).

METHODS

Patients with pSS and healthy controls were recruited. Serum GITRL and Th17-related cytokines were determined. RNA sequencing was performed to decipher key signal pathways. Nonobese diabetes (NOD) mice were adopted as experimental Sjögren models and recombinant adeno-associated virus (rAAV) transduction was conducted to verify the therapeutic potentials of targeting GITRL in vivo.

RESULTS

Serum GITRL was significantly higher in patients with pSS and showed a positive correlation with leukopenia, thrombocytopenia, autoantibodies, lung involvement, and disease activity. Serum GITRL was correlated with Th17-related cytokines. GITRL promoted the expansion of Th17 and Th17.1 cells. Expansion of granulocyte-macrophage colony-stimulating factor positive (GM-CSF+) CD4+ T cells induced by GITRL could be inhibited by blockade of GITRL. Moreover, GM-CSF could stimulate GITRL expression on monocytes. RNA sequencing revealed mammalian target of rapamycin complexes 1 (mTORC1) might be the key modulator. The increased phosphorylation of S6 and STAT3 and the expansion of Th17 and Th17.1 cells induced by GITRL were effectively inhibited by rapamycin, suggesting a GITRL-mTORC1-GM-CSF positive loop in pathogenic Th17 response in pSS. Administration of an rAAV vector expressing short hairpin RNA targeting GITRL alleviated disease progression in NOD mice.

CONCLUSION

Our results identified the pathogenic role of GITRL in exacerbating disease activity and promoting pathogenic Th17 response in pSS through a GITRL-mTORC1-GM-CSF loop. These findings suggest GITRL might be a promising therapeutic target in the treatment of pSS.

Regulatory role of PI16 in autoimmune arthritis and intestinal inflammation: implications for Treg cell differentiation and function

BACKGROUND

Regulatory T cells (Tregs) are crucial in maintaining immune homeostasis and preventing autoimmunity and inflammation. A proportion of Treg cells can lose Foxp3 expression and become unstable under inflammation conditions. The precise mechanisms underlying this phenomenon remain unclear.

METHODS

The PI16 gene knockout mice (PI16fl/flFoxp3Cre) in Treg were constructed, and the genotypes were identified. The proportion and phenotypic differences of immune cells in 8-week-old mice were detected by cell counter and flow cytometry. Two groups of mouse Naïve CD4+T cells were induced to differentiate into iTreg cells to observe the effect of PI16 on the differentiation and proliferation of iTreg cells, CD4+CD25+Treg and CD4+CD25- effector T cells (Teff) were selected and co-cultured with antigen presenting cells (APC) to observe the effect of PI16 on the inhibitory ability of Treg cells in vitro. The effects of directed knockout of PI16 in Treg cells on inflammatory symptoms, histopathological changes and immune cell expression in mice with enteritis and autoimmune arthritis were observed by constructing the model of antigen-induced arthritis (AIA) and colitis induced by dextran sulfate sodium salt (DSS).

RESULTS

We identified peptidase inhibitor 16 (PI16) as a negative regulator of Treg cells. Our findings demonstrate that conditional knock-out of PI16 in Tregs significantly enhances their differentiation and suppressive functions. The conditional knockout of the PI16 gene resulted in a significantly higher abundance of Foxp3 expression (35.12 ± 5.71% vs. 20.00 ± 1.61%, p = 0.034) in iTreg cells induced in vitro compared to wild-type mice. Mice with Treg cell-specific PI16 ablation are protected from autoimmune arthritis (AIA) and dextran sulfate sodium (DSS)-induced colitis development. The AIA model of PI16CKO is characterized by the reduction of joint structure and the attenuation of synovial inflammation and in DSS-induced colitis model, conditional knockout of the PI16 reduce intestinal structural damage. Additionally, we found that the deletion of the PI16 gene in Treg can increase the proportion of Treg (1.46 ± 0.14% vs. 0.64 ± 0.07%, p < 0.0001) and decrease the proportion of Th17 (1.00 ± 0.12% vs. 3.84 ± 0.64%, p = 0.001). This change will enhance the shift of Th17/Treg toward Treg cells in AIA arthritis model (0.71 ± 0.06% vs. 8.07 ± 1.98%, p = 0.003). In DSS-induced colitis model of PI16CKO, the proportion of Treg in spleen was significantly increased (1.40 ± 0.15% vs. 0.50 ± 0.11%, p = 0.003), Th17 (2.18 ± 0.55% vs. 6.42 ± 1.47%, p = 0.017), Th1 (3.42 ± 0.19% vs. 6.59 ± 1.28%, p = 0.028) and Th2 (1.52 ± 0.27% vs. 2.76 ± 0.38%, p = 0.018) in spleen was significantly decreased and the Th17/Treg balance swift toward Treg cells (1.44 ± 0.50% vs. 24.09 ± 7.18%, p = 0.012).

CONCLUSION

PI16 plays an essential role in inhibiting Treg cell differentiation and function. Conditional knock out PI16 gene in Treg can promote the Treg/Th17 balance towards Treg dominance, thereby alleviating the condition. Targeting PI16 may facilitate Treg cell-based therapies for preventing autoimmune diseases and inflammatory diseases. The research provides us with novel insights and future research avenues for the treatment of autoimmune diseases, particularly arthritis and colitis.

IL-17: a novel player in the pathogenesis of vulvar lichen sclerosus

Introduction

Vulvar lichen sclerosus (VLS) is a chronic progressive, lymphocyte-mediated inflammatory disease whose pathogenesis is complex and not fully elucidated.

Aim

In the current study we have investigated for the first time the expression of interleukin-17 (IL-17) and S100A7 in lesional skin obtained from female individuals with histologically confirmed VLS.

Material and methods

In our study we used skin biopsies obtained from female patients with histologically confirmed VLS (n = 20) and skin samples from healthy age- and gender-matched individuals (plastic surgery procedures) (n = 10) serving as controls. The tissue expressions of IL-17 and S100A7 were assessed with an immunohistochemical method.

Results

The number of cells showing IL-17 expression was significantly higher in VLS lesional skin as compared to normal skin of healthy controls (p < 0.0001). In VLS lesional skin, IL-17 was expressed in the epidermis and by cells within the inflammatory infiltrate in the upper dermis. The number of cells showing S100A7 expression was significantly higher in VLS lesional skin as compared to normal skin of healthy controls (p < 0.0001). In VLS lesional skin, S100A7 was expressed by suprabasal keratinocytes in epidermis. S100A7 was also expressed by cells within the inflammatory infiltrate in the dermis.

Conclusions

The results of our study may suggest the involvement of IL-17 and S100A7 in the pathogenesis of VLS. The better understanding of this disease may lead to the development of novel, effective therapeutic strategies e.g. using well-known biologics IL-17 inhibitors class.

Efficacy and Safety of Risankizumab in Patients with Psoriatic Arthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

Currently, the cause of psoriatic arthritis (PsA) is unknown, and the effectiveness of current drug treatments is unsatisfactory. In March 2019, the US Food and Drug Administration (FDA) approved risankizumab, a humanized immunoglobulin G1 (IgG1) monoclonal antibody targeting the p19 subunit of interleukin (IL)-23, for the treatment of PsA in adults. This study aimed to conduct a meta-analysis of double-blind, randomized, placebo-controlled trials to evaluate the effectiveness and safety of risankizumab in moderate-to-severe PsA.

METHODS

We conducted a thorough search of relevant databases from the establishment of the databases to October 1, 2023. We conducted a meta-analysis using Stata 12.0 and utilized I2 and Egger tests to assess heterogeneity and publication bias among the studies. Bias assessment was performed using the risk bias map and bias risk summary diagram generated by Revman5.4 software. The review protocols were registered on PROSPERO (CRD42023451894) and adhered to the preferred reporting item of system evaluation (PRISMA) guideline.

RESULTS

Six randomized controlled trials (RCTs) involving 5038 patients with PsA treated with either risankizumab or placebo were included in the analysis. At 24 weeks, the risankizumab group demonstrated a significantly higher American College of Rheumatology-20 (ACR20) response rate compared to the placebo group (RR 1.760, 95% CI 1.568-1.977, P < 0.001). Additionally, the risankizumab group showed a significantly higher Minimal Disease Activity (MDA) response rate compared to the placebo group (RR 1.827, 95% CI 1.048-3.184, P < 0.05). The risankizumab group also exhibited improvement in Short Form 36 Questionnaire (SF-36) score (SMD 0.51, 95% CI 0.33-0.69, P < 0.001), with significantly lower Health Assessment Questionnaire Disability Index (HAQ-DI) score (SMD - 0.27, 95% CI - 0.37 to - 0.17, P < 0.001) and higher Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) score (SMD 0.27, 95% CI 0.20-0.35, P < 0.001) compared to the placebo group. Moreover, the risankizumab group had a significantly lower Psoriasis Area and Severity Index (PASI) score (SMD - 6.12, 95% CI - 10.02 to 2.23, P < 0.001). A study by Mease et al. indicated that patients receiving risankizumab generally demonstrated numerical improvements in the Leeds Enthesitis Index (LEI), although the small sample size limits the evidence. Further research is necessary to provide evidence-based guidelines. There were no significant differences in the incidence of serious adverse events (SAE) and serious treatment-emergent adverse events (STEAE) between the risankizumab and placebo groups (RR 0.76, 95% CI 0.45-1.28, P = 0.31; RR 0.99, 95% CI 0.49-1.99, P = 0.97, respectively), and the overall incidence of adverse events (AE) was not comparable (RR 1.10, 95% CI 0.63-1.94, P = 0.73).

CONCLUSION

Risankizumab showed superior efficacy across multiple outcome measures compared to placebo, with no significant increase in adverse events. Our findings endorse risankizumab as an excellent treatment option for PsA, offering valuable insights for clinicians and patients when choosing appropriate therapeutic interventions.

TRIAL REGISTRATION

Retrospectively registered (CRD42023451894, 16 August 2023).

Chondrocyte-Targeted Delivery System of Sortase A-Engineered Extracellular Vesicles Silencing MMP13 for Osteoarthritis Therapy

Targeted drug delivery and the reduction of off-target effects are crucial for the promising clinical application of nucleic acid drugs. To address this challenge, a new approach for treating osteoarthritis (OA) that accurately delivers antisense oligonucleotides (ASO) targeting matrix metalloproteinase-13 (ASO-MMP13) to chondrocytes, is developed. Small extracellular vesicles (exos) are ligated with chondrocyte affinity peptide (CAP) using Sortase A and subsequently incubated with cholesterol-modified ASO-MMP13 to construct a chondrocyte-targeted drug delivery exo (CAP-exoASO). Compared with exos without CAP (ExoASO), CAP-exoASOs attenuate IL-1β-induced chondrocyte damage and prolong the retention time of ASO-MMP13 in the joint without distribution in major organs following intra-articular injection. Notably, CAP-exoASOs decrease MMP13 expression (P < 0.001) and upregulate COL2A1 expression (P = 0.006), resulting in reorganization of the cartilage matrix and alleviation of progression in the OA model. Furthermore, the Osteoarthritis Research Society International (OARSI) score of articular cartilage tissues treated with CAP-exoASO is comparable with that of healthy rats (P = 0.148). A mechanistic study demonstrates that CAP-exoASO may reduce inflammation by suppressing the IL-17 and TNF signaling pathways. Based on the targeted delivery effect, CAP-exoASOs successfully accomplish cartilage repair and have considerable potential for development as a promising therapeutic modality for satisfactory OA therapy.

Dupilumab-associated inflammatory arthritis: a literature review

Dupilumab is a fully human monoclonal antibody that acts by inhibiting the interleukin (IL)-4 receptor subunit α, and hence the IL-4 and IL-13 signalling pathway. Dupilumab treatment has been linked to the onset of T helper 17-driven inflammatory diseases, including cases of seronegative arthritis and enthesitis. To date, dupilumab-associated inflammatory arthritis (DAIA) represents a relatively unknown adverse event, initially reported in single cases or case series reports. Indeed, the onset of DAIA may not be promptly recognized, and is probably underestimated. Here we have reviewed the available English literature regarding arthritis and enthesitis onset during dupilumab treatment for atopic dermatitis, aiming to improve rapid recognition and thus prompt treatment of these diseases.

Microneedle-assisted percutaneous delivery of methotrexate-loaded nanoparticles enabling sustained anti-inflammatory effects in psoriasis therapy

Methotrexate (MTX) is one of the first-line drugs used for the treatment of moderate to severe psoriasis. However, low bioavailability and systemic side effects of traditional oral and injectable MTX greatly limit its clinical application. Delivering MTX using dissolving microneedles (MNs) into psoriasis-like skin lesion could improve the in situ therapeutic effects with higher bioavailability and less side effects. Here, we propose a novel therapeutic approach for psoriasis involving MN-assisted percutaneous delivery of chitosan-coated hollow mesoporous silica nanoparticles containing MTX (MTX@HMSN/CS). The MTX@HMSN/CS-loaded MNs were strong enough to successfully penetrate the psoriasiform thickened epidermis, allowing MTX@HMSN/CS to be accurately delivered to the site of skin lesion following the rapid dissolution of MNs. MTX was then released continuously from HMSN/CS for at least one week to maintain effective therapeutic drug concentration for skin lesion with long-term anti-proliferative and anti-inflammatory effects. Incubation with MTX@HMSN/CS not only inhibited the proliferation of human immortalized keratinocytes (HaCaT cells), but also significantly reduced the expression of proinflammatory cytokines and chemokines. In addition, MTX@HMSN/CS-loaded MNs showed better efficacy in alleviating psoriasis-like skin inflammation than MTX-loaded MNs at the same dose. Compared to psoriasiform mice treated with 15.8 μg MTX-loaded MNs every day, 47.4 μg MTX@HMSN/CS-loaded MNs reduce the frequency of treatment to once every 3 days and achieve comparable amelioration. Therefore, MTX@HMSN/CS loaded MNs are a promising treatment strategy for psoriasis due to their durability, efficacy, convenience, and safety in relieving psoriasis-like skin inflammation.

IL-23/IL-17 axis levels in gingival crevicular fluid of subjects with periodontal disease: a systematic review

BACKGROUND

The IL-23/IL-17 axis plays an important role in the immunopathogenesis of periodontal disease. A systematic review was conducted to synthesize all research reporting on the levels of the IL-23/IL-17 axis in gingival crevicular fluid (GCF) from subjects with gingivits, and periodontitis, compared to healthy controls.

METHODS

The protocol followed the PRISMA, and Cochrane guidelines, and was registered with the Open Science Framework (OSF): https://doi.org/10.17605/OSF.IO/7495V . A search was conducted in the electronic databases PubMed/MEDLINE, Scopus, Google Schoolar, and Cochrane from November 15th, 2005, to May 10th, 2023. The quality of the studies was assessed using the JBI tool for cross-sectional studies.

RESULTS

The search strategy provided a total of 2,098 articles, of which 12 investigations met the inclusion criteria. The total number of patients studied was 537, of which 337 represented the case group (subjects with gingivitis, and chronic periodontitis), and 200 represented the control group (periodontally healthy subjects). The ages of the patients ranged from 20 to 50 years, with a mean (SD) of 36,6 ± 4,2, of which 47% were men, and 53% were women. 75% of the investigations collected GCF samples with absorbent paper strips, and analyzed cytokine IL-17 levels individually. In addition, qualitative analysis revealed that there are differences between IL-23/IL-17 axis levels in subjects with chronic periodontitis, gingivitis and healthy controls.

CONCLUSIONS

Thus, IL-23/IL-17 axis levels could be used in the future as a diagnostic tool to distinguish between periodontal diseases.

Treatment of non-systemic juvenile idiopathic arthritis

In the past two decades, the treatment of juvenile idiopathic arthritis (JIA) has evolved markedly, owing to the availability of a growing number of novel, potent and relatively safe therapeutic agents and the shift of management strategies towards early achievement of disease remission. However, JIA encompasses a heterogeneous group of diseases that require distinct treatment approaches. Furthermore, some old drugs, such as methotrexate, sulfasalazine and intraarticular glucocorticoids, still maintain an important therapeutic role. In the past 5 years, information on the efficacy and safety of drug therapies for JIA has been further enriched through the accomplishment of several randomized controlled trials of newer biologic and synthetic targeted DMARDs. In addition, a more rational therapeutic approach has been fostered by the promulgation of therapeutic recommendations and guidelines. A multinational collaborative effort has led to the development of the recommendations for the treat-to-target strategy in JIA. There is currently increasing interest in establishing the optimal time and modality for discontinuation of treatment in children with JIA who achieve sustained clinical remission. The aim of this Review is to summarize the current evidence and discuss the therapeutic approaches to the management of non-systemic phenotypes of JIA, including oligoarthritis, polyarthritis, enthesitis-related arthritis and psoriatic arthritis.

A Novel Human Interleukin-23A Overexpressing Mouse Model of Systemic Lupus Erythematosus

OBJECTIVE

Interleukin-23 (IL-23) is a crucial cytokine implicated in chronic inflammation and autoimmunity, associated with various diseases such as psoriasis, psoriatic arthritis, and systemic lupus erythematosus (SLE). This study aimed to create and characterize a transgenic mouse model overexpressing human IL-23A (TghIL-23A), providing a valuable tool for investigating the pathogenic role of human IL-23A and evaluating the efficacy of anti-human IL-23A therapeutics.

METHODS

TghIL-23A mice were generated via microinjection of CBA × C57BL/6 zygotes with a fragment of the human IL23A gene, flanked by its 5'-regulatory sequences and the 3' untranslated region of human β-globin. The TghIL-23A pathology was assessed through hematologic and biochemic analyses, cytokine and antinuclear antibody detection, and histopathologic examination of skin and renal tissues. The response to the anti-human IL-23A therapeutic agent guselkumab was evaluated in groups of eight mixed-sex mice receiving subcutaneous treatment twice weekly for 10 weeks using clinical, biomarker, and histopathologic readouts.

RESULTS

TghIL-23A mice exhibited interactions between human IL-23A and mouse IL-23/IL-12p40 and developed a chronic multiorgan autoimmune disease marked by proteinuria, anti-double-stranded DNA antibodies, severe inflammatory lesions in the skin, and milder phenotypes in the kidneys and lungs. The TghIL-23A pathologic features exhibited significant similarities to those observed in human patients with SLE, and they were reversed following guselkumab treatment.

CONCLUSION

We have generated and characterized a novel genetic mouse model of SLE, providing proof-of-concept for the etiopathogenic role of human IL-23A. This new model has a normal life span and integrates several characteristics of the human disease's complexity and chronicity, making it an attractive preclinical tool for studying IL-23-dependent pathogenic mechanisms and assessing the efficacy of anti-human IL-23A or modeled disease-related therapeutics.

Is occupational noise associated with arthritis? Cross-sectional evidence from US population

BACKGROUND

The impact of occupational noise exposure on various diseases, including ear and cardiovascular diseases, has been studied extensively. Nevertheless, the connection between osteoarthritis (OA) and rheumatoid arthritis (RA) and occupational noise exposure remains largely unexplored in real-world scenarios. This study assessed the association between occupational noise exposure and the prevalence of two types of arthritis.

METHODS

This study used database data from 2005 to 2012 and 2015-March 2020 from the prepandemic National Health and Nutrition Examination Survey (NHANES) related to occupational noise exposure and arthritis. Multivariate logistic regression analysis was used to estimate the association between occupational noise exposure and RA/OA, adjusting for age, gender, race, education level, marital status, the ratio of family income to poverty, trouble sleeping, smoking status, alcohol consumption, diabetes, hypertension, body mass index (BMI), metabolic equivalents (METs), and thyroid disease.

RESULTS

This study included 11,053 participants. Multivariate logistic regression analysis demonstrated that previous exposure to occupational noise was positively associated with self-reported RA (OR = 1.43, 95% CI = 1.18-1.73) and OA (OR = 1.25, 95% CI = 1.07-1.46). Compared to individuals without a history of occupational noise exposure, those with an exposure duration of 1 year or greater exhibited higher odds of prevalent RA, though there was no apparent exposure response relationship for noise exposure durations longer than 1 year. The results of our subgroup analyses showed a significant interaction between age and occupational noise exposure on the odds of self-reported prevalent OA.

CONCLUSIONS

Our findings suggest an association between occupational noise exposure and the prevalence of RA and OA. Nevertheless, further clinical and basic research is warranted to better explore their associations.

Nanobodies in cytokine‑mediated immunotherapy and immunoimaging (Review)

Cytokines are the main regulators of innate and adaptive immunity, mediating communications between the cells of the immune system and regulating biological functions, including cell motility, differentiation, growth and apoptosis. Cytokines and cytokine receptors have been used in the treatment of tumors and autoimmune diseases, and to intervene in cytokine storms. Indeed, the use of monoclonal antibodies to block cytokine‑receptor interactions, as well as antibody‑cytokine fusion proteins has exhibited immense potential for the treatment of tumors and autoimmune diseases. Compared with these traditional types of antibodies, nanobodies not only maintain a high affinity and specificity, but also have the advantages of high thermal stability, a high capacity for chemical manipulation, low immunogenicity, good tissue permeability, rapid clearance and economic production. Thus, nanobodies have extensive potential for use in the diagnosis and treatment of cytokine‑related diseases. The present review summarizes the application of nanobodies in cytokine‑mediated immunotherapy and immunoimaging.

α-mangostin derivatives ameliorated mouse DSS-induced chronic colitis via regulating Th17/Treg balance

Th17 cell, an important subpopulation of helper T cell, plays an important role in the development of inflammatory bowel disease (IBD) and is thought to be a potential target for the treatment of IBD. In our previous study, we demonstrated that α-mangostin could relieve lupus nephritis via inhibiting Th17 cell function. In our preliminary study, we obtained four derivatives by adding chemical modification of α-mangostin which could also inhibit Th17 cell differentiation in vitro. In this study, we constructed a chronic IBD mouse model and demonstrated the therapeutic effects of α-mangostin and its derivatives as therapeutic agents for IBD. In compounds treating groups, intestinal inflammation showed significant improvement in symptoms which included weight loss, high disease activity index, colon length shorten and the change of intestinal flora. We also found that compounds could effectively either suppress the number of Th17 cell or increase the number of Treg cell detected by flow cytometry, thus reducing the Th17/Treg ratio and suppressing the level of intestinal inflammation. Notably, IL17-F levels, rather than IL17-A, were reduced in the colon of mice of compounds treating groups. Thus, α-mangostin and its derivatives ameliorate DSS-induced chronic colitis in mice by regulating Th17/Treg balance to alleviate intestinal inflammation and can modulate the intestinal microbial community. These results suggest that α-mangostin and its derivatives may be the new therapeutic option for chronic colitis.

Upadacitinib for the treatment of adults with active non-radiographic axial spondyloarthritis (nr-axSpA)

INTRODUCTION

Non-radiographic axial spondyloarthritis (nr-axSpA) is a chronic inflammatory condition with axial and peripheral musculoskeletal involvement, fulfilling criteria of axSpA in the absence of advanced radiographic sacroiliitis. While appropriate treatment is required for chronic pain and disability resulting from disease progression, the limited availability of treatment options becomes evident. Upadacitinib, an oral selective Janus kinase 1 inhibitor, was approved in Europe, the United States, and other countries for management of nr-axSpA with inadequate response to existing therapies.

AREA COVERED

This review summarizes essential drug profiles, efficacy, and safety of upadacitinib for nr-axSpA in conjunction with data pertaining to radiographic axSpA.

EXPERT OPINION

In a phase 3 trial, upadacitinib exhibited efficacy for patients with nr-axSpA, irrespective of prior exposures to biological disease-modifying antirheumatic drugs (bDMARDs). The safety profiles of upadacitinib in nr-axSpA mirrored those in other indications, underscoring its potential as a promising treatment option for nr-axSpA. Concurrently, physicians should be aware of the absence of real-world data, longitudinal efficacy and safety, direct comparative studies between upadacitinib and bDMARDs in nr-axSpA, and evidence for precision medicine to identify patients who may optimally benefit from upadacitinib over bDMARDs. Future research is imperative to facilitate the effective utilization of upadacitinib in daily clinical practice.

Application of Cartilage Extracellular Matrix to Enhance Therapeutic Efficacy of Methotrexate

BACKGROUND

Rheumatoid arthritis (RA) is characterized by chronic inflammation and joint damage. Methotrexate (MTX), a commonly used disease-modifying anti-rheumatic drug (DMARD) used in RA treatment. However, the continued use of DMARDs can cause adverse effects and result in limited therapeutic efficacy. Cartilage extracellular matrix (CECM) has anti-inflammatory and anti-vascular effects and promotes stem cell migration, adhesion, and differentiation into cartilage cells.

METHODS

CECM was assessed the dsDNA, glycosaminoglycan, collagen contents and FT-IR spectrum of CECM. Furthermore, we determined the effects of CECM and MTX on cytocompatibility in the SW 982 cells and RAW 264.7 cells. The anti-inflammatory effects of CECM and MTX were assessed using macrophage cells. Finally, we examined the in vivo effects of CECM in combination with MTX on anti-inflammation control and cartilage degradation in collagen-induced arthritis model. Anti-inflammation control and cartilage degradation were assessed by measuring the serum levels of RA-related cytokines and histology.

RESULTS

CECM in combination with MTX had no effect on SW 982, effectively suppressing only RAW 264.7 activity. Moreover, anti-inflammatory effects were enhanced when low-dose MTX was combined with CECM. In a collagen-induced arthritis model, low-dose MTX combined with CECM remarkably reduced RA-related and pro-inflammatory cytokine levels in the blood. Additionally, low-dose MTX combined with CECM exerted the best cartilage-preservation effects compared to those observed in the other therapy groups.

CONCLUSION

Using CECM as an adjuvant in RA treatment can augment the therapeutic effects of MTX, reduce existing drug adverse effects, and promote joint tissue regeneration.

Association of Interleukin 23 Receptor Polymorphisms with Predisposition to Rheumatoid Arthritis: An Updated Meta and Trial Sequential Analysis

The etiology of Rheumatoid Arthritis (RA) development remained unclear, and several factors, such as environmental, genetic, and immune system dysfunction, have been attributed to the susceptibility. Interleukin 23 (IL23) induces expansion of the Th17 cells through the IL-23 receptor (IL-23R) and believes in playing a major role in RA pathogenesis. Various genetic mutants in the IL23R gene (rs10489629, rs1343151, rs2201841, rs7517847, rs1004819, rs10889677, rs11209026, rs7530511) have been associated with the susceptibility RA, but results are contradictories. We performed a meta-analysis to establish the association of IL23R polymorphisms with susceptibility RA. For the meta-analysis, a detailed search of databases like Google Scholar, PubMed, Scopus, Web of Science, and Science Direct was conducted, and data were extracted from the included reports. The meta-analysis was performed by the Comprehensive Meta-Analysis v3 software. A significant association of IL-23R rs11209026 (AA vs. GG: Odds ratio = 2.250, p-value = 0.01; AA vs. GG+GA: Odds ratio = 2.271, p-value = 0.01), rs1343151 (A vs. G: Odds ratio = 1.091, p-value = 0.001; AA vs. GG: Odds ratio = 1.209, p-value = 0.001; GA vs. GG: Odds ratio = 1.116, p-value = 0.004; AA+GA vs. GG: Odds ratio = 1.135, p-value = 0.000; AA vs. GG+GA: Odds ratio = 1.144, p-value = 0.012) and rs10889677 (CA vs. CC: Odds ratio = 1.375, p-value = 0.041) polymorphisms were observed with increased susceptibility for the development of RA. In contrast, IL-23R rs10489629 (G vs. A: odds ratio = 0.901, p-value = 0.047, GG vs. AA: Odds ratio = 0.763, p-value = 0.022, GG vs. AA+AG: Odds ratio = 0.852, p-value = 0.00) and IL23R rs2201841 (CC vs. TT+TC: Odds ratio = 0.826, p-value = 0.026) variants were linked with protection against the development of RA. In addition, the trial sequential analysis revealed the inclusion of a sufficient number of studies in the present meta-analysis, and no further additional studies are required. IL-23R variants are associated with genetic susceptibility or resistance against the development of RA.

Augmenting regulatory T cells: new therapeutic strategy for rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic, systemic autoimmune condition marked by inflammation of the joints, degradation of the articular cartilage, and bone resorption. Recent studies found the absolute and relative decreases in circulating regulatory T cells (Tregs) in RA patients. Tregs are a unique type of cells exhibiting immunosuppressive functions, known for expressing the Foxp3 gene. They are instrumental in maintaining immunological tolerance and preventing autoimmunity. Increasing the absolute number and/or enhancing the function of Tregs are effective strategies for treating RA. This article reviews the studies on the mechanisms and targeted therapies related to Tregs in RA, with a view to provide better ideas for the treatment of RA.

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.

Based on Weighted Gene Co-Expression Network Analysis Reveals the Hub Immune Infiltration-Related Genes Associated with Ulcerative Colitis

Purpose

Immune infiltration plays a pivotal role in the pathogenesis of mucosal damage in ulcerative colitis (UC). The objective of this study was to systematically analyze and identify genetic characteristics associated with immune infiltration in UC.

Patients and Methods

Gene expression data from three independent datasets obtained from the Gene Expression Omnibus (GEO) were utilized. By employing the ssGSEA and CIBERSORT algorithms, we estimated the extent of immune cell infiltration in UC samples. Subsequently, Weighted Correlation Network Analysis (WGCNA) was performed to identify gene modules exhibiting significant associations with immune infiltration, and further identification of hub genes associated with immune infiltration was accomplished using least absolute shrinkage and selection operator (LASSO) regression analysis. The relationship between the identified hub genes and clinical information was subsequently investigated.

Results

Our findings revealed significant activation of both innate and adaptive immune cells in UC. Notably, the expression levels of CD44, IL1B, LYN, and ITGA5 displayed strong correlations with immune cell infiltration within the mucosa of UC patients. Immunohistochemical analysis confirmed the significant upregulation of CD44, LYN, and ITGA5 in UC samples, and their expression levels were found to be significantly associated with common inflammatory markers, including the systemic immune inflammation indices, C-reactive protein, and erythrocyte sedimentation rate.

Conclusion

CD44, LYN, and ITGA5 are involved in the immune infiltration pathogenesis of UC and may be potential therapeutic targets for UC.

Umbilical Cord Mesenchymal Stromal/Stem Cells and Their Interplay with Th-17 Cell Response Pathway

As a form of immunomodulatory therapeutics, mesenchymal stromal/stem cells (MSCs) from umbilical cord (UC) tissue were assessed for their dynamic interplay with the Th-17 immune response pathway. UC-MSCs were able to modulate lymphocyte response by promoting a Th-17-like profile. Such modulation depended on the cell ratio of the cocultures as well as the presence of an inflammatory setting underlying their plasticity. UC-MSCs significantly increased the expression of IL-17A and RORγt but differentially modulated T cell expression of IL-23R. In parallel, the secretion profile of the fifteen factors (IL1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-22, IL-21, IL-23, IL-25, IL-31, IL-33, INF-γ, sCD40, and TNF-α) involved in the Th-17 immune response pathway was substantially altered during these cocultures. The modulation of these factors demonstrates the capacity of UC-MSCs to sense and actively respond to tissue challenges. Protein network and functional enrichment analysis indicated that several biological processes, molecular functions, and cellular components linked to distinct Th-17 signaling interactions are involved in several trophic, inflammatory, and immune network responses. These immunological changes and interactions with the Th-17 pathway are likely critical to tissue healing and may help to identify molecular targets that will improve therapeutic strategies involving UC-MSCs.

Global trends and research status in ankylosing spondylitis clinical trials: a bibliometric analysis of the last 20 years

Background

Ankylosing spondylitis (AS) is a rheumatic and autoimmune disease associated with a chronic inflammatory response, mainly characterized by pain, stiffness, or limited mobility of the spine and sacroiliac joints. Severe symptoms can lead to joint deformity, destruction, and even lifelong disability, causing a serious burden on families and society as a whole. A large number of clinical studies have been published on AS over the past 20 years. This study aimed to summarize the current research status and global trends relating to AS clinical trials through a bibliometric analysis.

Methods

The Web of Science Core Collection database was searched for publications related to AS clinical trials published between January 2003 and June 2023. Bibliometric analysis and web visualization were performed using CiteSpace, VOSviewer, and a bibliometric online analysis platform (https://bibliometric.com), which included the number of publications, citations, countries, institutions, journals, authors, references, and keywords.

Results

1,212 articles published in 201 journals from 65 countries were included in this study. The number of publications related to AS clinical trials is increasing annually. The United States and the Free University of Berlin, the countries and institutions, respectively, that have published the most articles on AS, have made outstanding contributions to this field. The author with the most published papers and co-citations over the period covered by the study was Desiree Van Der Heijde. The journal with the most published and cited articles was Annals of the Rheumatic Diseases. The keywords: "double-blind," "rheumatoid arthritis," "efficacy," "placebo-controlled trial," "infliximab," "etanercept," "psoriatic arthritis" and "therapy" represent the current research hotspots regarding AS.

Discussion

This is the first study to perform a bibliometric analysis and visualization of AS clinical trial publications, providing a reliable research focus and direction for clinicians. Future studies in the field of AS clinical trials should focus on placebo-controlled trials of targeted therapeutic drugs.

Targeting fusion proteins of the interleukin family: A promising new strategy for the treatment of autoinflammatory diseases

As a means of communication between immune cells and non-immune cells, Interleukins (ILs) has the main functions of stimulating the proliferation and activation of inflammatory immune cells such as dendritic cells and lymphocytes, promote the development of blood cells and so on. However, dysregulation of ILs expression is a major feature of autoinflammatory diseases. The drugs targeting ILs or IL-like biologics have played an important role in the clinical treatment of autoinflammatory diseases. Nevertheless, the widespread use of IL products may result in significant off-target adverse reactions. Thus, there is a clear need to develop next-generation ILs products in the biomedical field. Fusion proteins are proteins created through the joining of two or more genes that originally coded for separate proteins. Over the last 30 years, there has been increasing interest in the use of fusion protein technology for developing anti-inflammatory drugs. In comparison to single-target drugs, fusion proteins, as multiple targets drugs, have the ability to enhance the cytokine therapeutic index, resulting in improved efficacy over classical drugs. The strategy of preparing ILs or their receptors as fusion proteins is increasingly used in the treatment of autoimmune and chronic inflammation. This review focuses on the efficacy of several fusion protein drugs developed with ILs or their receptors in the treatment of autoinflammatory diseases, in order to illustrate the prospects of this new technology as an anti-inflammatory drug development protocol in the future.

Elevated levels of peripheral Th17 cells and Th17-related cytokines in patients with periampullary adenocarcinoma

AIM

Periampullary adenocarcinoma (PAC) is a malignant tumor originating at the ampulla of Vater, distal common bile duct, head of the pancreas, ampulla and duodenum. The levels of circulating Th17 cells and Th17-related cytokines in patients with PAC remain unreported. Therefore, the aim of this study was to determine the levels of circulating Th17 cells and Th17-related cytokines in patients with PAC.

MATERIALS AND METHODS

Flow cytometry was used to measure Th17 cell proportions in PBMCs from 60 PAC patients and 30 healthy controls. Enzyme-linked immunosorbent assay (ELISA) was used to quantify IL-17A and IL-23 levels in serum samples, while quantitative reverse transcription polymerase chain reaction (qRT-PCR) assessed IL-17A mRNA expression and Th17-related transcription factors (RORγt and STAT3) in tissue samples.

RESULTS

The findings showed a substantial increase in Th17 cell percentages, elevated concentrations of IL-17A and IL-23, and higher mRNA expression levels of IL-17A, RORγt, and STAT3 in patients with PAC when compared to healthy controls (HCs).

CONCLUSION

Th17 cells play an important role in the pathogenesis of PAC and may represent potential therapeutic targets.

Interleukin (IL)-23, IL-31, and IL-33 Play a Role in the Course of Autoimmune Endocrine Diseases

BACKGROUND

Interleukins (IL)-23, 31, and 33 are involved in the regulation of T helper 17 (Th17)/regulatory T (Treg) cells balance. The role of IL-23, 31 and 33 in non-endocrine autoimmune diseases has been confirmed. Data on the involvement of these cytokines in endocrine autoimmune diseases are limited.

OBJECTIVE

This study aimed to determine the involvement of cytokines regulating the T helper 17 (Th17)/regulatory T (Treg) cells axis in the course of autoimmune endocrine diseases.

METHODS

A total number of 80 participants were divided into 4 groups: the autoimmune polyendocrine syndrome (APS) group consisting of APS type 2 (APS-2) and type 3 (APS-3) subgroups, the Hashimoto's thyroiditis (HT) group, the Graves' disease (GD) group and the control (C) group. Fifteen cytokines related to Th17 and Treg lymphocytes were determined in the serum of all participants.

RESULTS

Higher levels of IL-23 and IL-31 were found in the APS, GD, and HT groups compared to the C group. Higher levels of IL-23 and IL-31 were also observed in the APS-2 group, in contrast to the APS-3 group. Correlation analysis of variables in the groups showed a statistically significant correlation between the cytokines IL-23, IL-31, and IL-33 in the APS and APS-2 groups, but no correlation in the APS-3 and C groups.

CONCLUSION

IL-23 and IL-31 are independent factors in the course of HT, GD, and APS-2, in contrast to APS-3. The positive correlation between IL-23 and IL-31, IL-23 and IL-33, and between IL-31 and IL-33 in the APS, APS-2 groups, but the lack of correlation in the APS-3 and C groups may further suggest the involvement of these cytokines in the course of Addison's disease.

IL-23 contributes to Particulate Matter induced allergic asthma in the early life of mice and promotes asthma susceptibility

Air pollutant exposure leads to and exacerbates respiratory diseases. Particulate Matter (PM) is a major deleterious factor in the pathophysiology of asthma. Nonetheless, studies on the effects and mechanisms of exposure in the early life of mice remain unresolved. This study aimed to investigate changes in allergic phenotypes and effects on allergen-specific memory T cells resulting from co-exposure of mice in the early life to PM and house dust mites (HDM) and to explore the role of interleukin-23 (IL-23) in this process. PM and low-dose HDM were administered intranasally in 4-day-old C57BL/6 mice. After confirming an increase in IL-23 expression in mouse lung tissues, changes in the asthma phenotype and lung effector/memory Th2 or Th17 cells were evaluated after intranasal administration of anti-IL-23 antibody (Ab) during co-exposure to PM and HDM. Evaluation was performed up to 7 weeks after the last administration. Co-exposure to PM and low-dose HDM resulted in increases in airway hyperresponsiveness (AHR), eosinophils, neutrophils, and persistent Th2/Th17 effector/memory cells, which were all inhibited by anti-IL-23 Ab administration. When low-dose HDM was administered twice after a 7-week rest, mice exposed to PM and HDM during the previous early life period exhibited re-increases AHR, eosinophil count, HDM-specific IgG1, and effector/memory Th2 and Th17 cell populations. However, anti-IL-23 Ab administration during the early life period resulted in inhibition. Co-exposure to PM and low-dose HDM reinforced the allergic phenotypes and allergen-specific memory responses in early life of mice. During this process, IL-23 contributes to the enhancement of effector/memory Th2/Th17 cells and allergic phenotypes. KEY MESSAGES: PM-induced IL-23 expression, allergic responses in HDMinstilled mice of early life period. PM-induced effector/memory Th2/Th17 cells in HDMinstilled mice of early life period. Inhibition of IL-23 reduced the increase in allergic responses. Inhibition of IL-23 reduced the increase in allergic responses. After the resting period, HDM administration showed re-increase in allergic responses. Inhibition of IL-23 reduced the HDM-recall allergic responses.

Relation between LRG1 and CD4+ T cells, cognitive impairment and neurological function in patients with acute ischemic stroke

Objective: To assess the relationship between LRG1 and CD4+ T cells, cognitive impairment and neurological function in acute ischemic stroke (AIS). Methods: Plasma LRG1 was detected by ELISA in 175 patients with AIS at baseline, day (D) 1, D7, month (M) 1 and M3. Results: LRG1 was negatively related to Th2 and Treg cells and positively linked to Th17 (all p < 0.05). LRG1 increased from baseline to D1, then decreased until M3 (p < 0.001). LRG1 at each assessment point was increased in patients with cognitive impairment or poor neurological function at M3 versus those without (all p < 0.05). Conclusion: LRG1 is linked to decreased Th2 and Tregs, increased Th17, cognitive impairment and nonideal neurological function recovery in patients with AIS.

Molecular mechanism of lncRNAs in pathogenesis and diagnosis of auto-immune diseases, with a special focus on lncRNA-based therapeutic approaches

Autoimmune diseases are a diverse set of conditions defined by organ damage due to abnormal innate and acquired immune system responses. The pathophysiology of autoimmune disorders is exceedingly intricate and has yet to be fully understood. The study of long non-coding RNAs (lncRNAs), non-protein-coding RNAs with at least 200 nucleotides in length, has gained significant attention due to the completion of the human genome project and the advancement of high-throughput genomic approaches. Recent research has demonstrated how lncRNA alters disease development to different degrees. Although lncRNA research has made significant progress in cancer and generative disorders, autoimmune illnesses are a relatively new research area. Moreover, lncRNAs play crucial functions in differentiating various immune cells, and their potential relationships with autoimmune diseases have received growing attention. Because of the importance of Th17/Treg axis in auto-immune disease development, in this review, we discuss various molecular mechanisms by which lncRNAs regulate the differentiation of Th17/Treg cells. Also, we reviewed recent findings regarding the several approaches in the application of lncRNAs in the diagnosis and treatment of human autoimmune diseases, as well as current challenges in lncRNA-based therapeutic approaches to auto-immune diseases.

Contribution of monocyte and macrophage extracellular traps to neutrophilic airway inflammation in severe asthma

BACKGROUND

Increased blood/sputum neutrophil counts are related to poor clinical outcomes of severe asthma (SA), where we hypothesized that classical monocytes (CMs)/CM-derived macrophages (Mφ) are involved. We aimed to elucidate the mechanisms of how CMs/Mφ induce the activation of neutrophils/innate lymphoid cells (ILCs) in SA.

METHODS

Serum levels of monocyte chemoattractant protein-1 (MCP-1) and soluble suppression of tumorigenicity 2 (sST2) were measured from 39 patients with SA and 98 those with nonsevere asthma (NSA). CMs/Mφ were isolated from patients with SA (n = 19) and those with NSA (n = 18) and treated with LPS/interferon-gamma. Monocyte/M1Mφ extracellular traps (MoETs/M1ETs) were evaluated by western blotting, immunofluorescence, and PicoGreen assay. The effects of MoETs/M1ETs on neutrophils, airway epithelial cells (AECs), ILC1, and ILC3 were assessed in vitro and in vivo.

RESULTS

The SA group had significantly higher CM counts with increased migration as well as higher levels of serum MCP-1/sST2 than the NSA group. Moreover, the SA group had significantly greater production of MoETs/M1ETs (from CMs/M1Mφ) than the NSA group. The levels of MoETs/M1ETs were positively correlated with blood neutrophils and serum levels of MCP-1/sST2, but negatively correlated with FEV1%. In vitro/in vivo studies demonstrated that MoETs/M1ETs could activate AECs, neutrophils, ILC1, and ILC3 by increased migration as well as proinflammatory cytokine production.

CONCLUSIONS

CM/Mφ-derived MoETs/M1ETs could contribute to asthma severity by enhancing neutrophilic airway inflammation in SA, where modulating CMs/Mφ may be a potential therapeutic option.

Exploring therapeutic avenues: mesenchymal stem/stromal cells and exosomes in confronting enigmatic biofilm-producing fungi

Fungal infections concomitant with biofilms can demonstrate an elevated capacity to withstand substantially higher concentrations of antifungal agents, contrasted with infectious diseases caused by planktonic cells. This inherent resilience intrinsic to biofilm-associated infections engenders a formidable impediment to effective therapeutic interventions. The different mechanisms that are associated with the intrinsic resistance of Candida species encompass drug sequestration by the matrix, drug efflux pumps, stress response cell density, and the presence of persister cells. These persisters, a subset of fungi capable of surviving hostile conditions, pose a remarkable challenge in clinical settings in virtue of their resistance to conventional antifungal therapies. Hence, an exigent imperative has arisen for the development of novel antifungal therapeutics with specific targeting capabilities focused on these pathogenic persisters. On a global scale, fungal persistence and their resistance within biofilms generate an urgent clinical need for investigating recently introduced therapeutic strategies. This review delves into the unique characteristics of Mesenchymal stem/stromal cells (MSCs) and their secreted exosomes, which notably exhibit immunomodulatory and regenerative properties. By comprehensively assessing the current literature and ongoing research in this field, this review sheds light on the plausible mechanisms by which MSCs and their exosomes can be harnessed to selectively target fungal persisters. Additionally, prospective approaches in the use of cell-based therapeutic modalities are examined, emphasizing the importance of further research to overcome the enigmatic fungal persistence.

Anti-inflammatory and anti-oxidant activities of mesenchymal stem cells in chemically induced arthritic rats

BACKGROUND

Mesenchymal stem cells (MSCs) have been extensively used as cell-based treatments for decades due to their anti-inflammatory, immunomodulatory, and healing abilities. The intent of our study was to determine the efficacy of MSCs in alleviating rheumatoid arthritis (RA) induced by Complete Freund's adjuvant (CFA) and to investigate the anti-inflammatory and antioxidant characteristics of MSCs.

METHODS AND RESULTS

Intrapedally injecting 0.1 ml of CFA directly into the footpad of the right hind paw daily for 2 days was used to induce RA. Arthritic rats received four doses of MSCs (1 × 106 cells/rat/dose) intravenously through the lateral tail vein. Our results showed that arthritic rats treated with MSCs exhibited reduced levels of paw edema. Furthermore, arthritic rats treated with MSCs exhibited a significant decrease in the levels of RF, CRP, IL-1β, TNF-α, IL-17 and ADAMTS-5, along with a significant increase in the levels of IL-4 and TIMP-3. Additionally, MSCs significantly reduced the expression of TGF-β. Both the glutathione (GSH) content and antioxidant activity of GST were enhanced by MSCs, while LPO levels were suppressed.

CONCLUSION

These findings provide further evidence that MSCs are valuable in treating RA, possibly due to their anti-inflammatory and anti-oxidative properties. Thus, MSCs have potential as a more effective therapeutic strategy for treating RA.

The Effects of IL-23/IL-18-Polarized Neutrophils on Renal Ischemia-Reperfusion Injury and Allogeneic-Skin-Graft Rejection in Mice

Neutrophils display heterogeneity and plasticity with different subgroups and immune-regulatory functions under various surrounding conditions. Neutrophils induced by IL-23/IL-18 (referred to N(IL-23+IL-18) neutrophils) have a unique gene-expression profile, with highly expressing IL-17, MHC-II, and costimulatory molecules. The adoptive transfer of N(IL-23+IL-18) neutrophils significantly increased the pathogenesis in a renal ischemia-reperfusion injury mouse model. N(IL-23+IL-18) neutrophils directly and efficiently induced allogeneic T cell proliferation in vitro. N(IL-23+IL-18) neutrophils enhanced the syngeneic T cell response to allogeneic antigens in mixed-lymphocyte reaction assays. The adoptive transfer of the donor or host N(IL-23+IL-18) neutrophils significantly enhanced the antidonor antibody production in an allogeneic-skin-transplanted mouse model, accompanied by increased Tfh cells in the spleens. Therefore, the neutrophil subset induced by IL-23/IL-18 promotes tissue injury and antidonor humoral response in the allogeneic transplantation mouse model.

Network pharmacology identifies the inhibitory effect of Yiqiyangyinquyu prescription on salivary gland inflammation in Sjögren's syndrome

This study aimed to explore the mode of action of Yiqiyangyinquyu prescription (YP) against Sjögren's syndrome (SS) by combining network pharmacology with molecular docking techniques. YP's active components and target proteins were identified using the BATMAN-traditional Chinese medicine database. Concurrently, targets associated with SS were extracted from databases, including Genecards, Online Mendelian Inheritance in Man, and Therapeutic Target Database. The standard targets were then imported into the STRING database to construct a protein-protein interaction network. We then conducted gene ontology and Kyoto encyclopedia of genes and genomes enrichment analyses, which were succeeded by molecular docking studies to validate core active components and key targets. Finally, in vitro experiments and molecular dynamics simulation were conducted to substantiate the therapeutic efficacy of YP in treating SS. A total of 206 intersection targets and 46 active compounds were identified. Gene ontology analysis unveiled that YP targets were primarily enriched in cellular responses to chemical stress, inflammation, and cell proliferation. Key enriched signaling pathways encompassed the interleukin 17, hypoxia-inducible factor-1, tumor necrosis factor (TNF-α), and advanced glycation end products-receptor for AGEs (AGE-RAGE) signaling pathways. Molecular docking results demonstrated high-affinity between neotanshinone C, tanshiquinone B, miltionone I, TNF-α, interleukin 1 beta (IL-1β), and interleukin 6 (IL-6). Noteworthy, TNF-α, considered the most important gene in YP against SS, binds to YP most stably, which was further validated by molecular dynamics simulation. In vitro experiments confirmed YP's capacity to reduce TNF-α, IL-1β, and IL-6 expression, effectively alleviating SS-related inflammation. YP demonstrated a significant anti-inflammatory effect by suppressing inflammatory cytokines (TNF-α, IL-6, and IL-1β), providing experimental evidence for its clinical application in treating SS.

Advances in the study of IL-17 in neurological diseases and mental disorders

Interleukin-17 (IL-17), a cytokine characteristically secreted by T helper 17 (Th17) cells, has attracted increasing attention in recent years because of its importance in the pathogenesis of many autoimmune or chronic inflammatory diseases. Recent studies have shown that neurological diseases and mental disorders are closely related to immune function, and varying degrees of immune dysregulation may disrupt normal expression of immune molecules at critical stages of neural development. Starting from relevant mechanisms affecting immune regulation, this article reviews the research progress of IL-17 in a selected group of neurological diseases and mental disorders (autism spectrum disorder, Alzheimer's disease, epilepsy, and depression) from the perspective of neuroinflammation and the microbiota-gut-brain axis, summarizes the commonalities, and provides a prospective outlook of target application in disease treatment.

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.

Differential effects of interleukin-17A and 17F on cell interactions between immune cells and stromal cells from synovium or skin

We compared the contribution of IL-17A and IL-17F in co-culture systems mimicking cell interactions as found in inflamed synovium and skin. Synoviocytes or skin fibroblasts were co-cultured with activated PBMC, with IL-17A, IL-17 A/F, IL-17F, IL-23, anti-IL-17A, anti-IL-17A/F or anti-IL-17F antibodies. IL-17A, IL-17F, IL-6 and IL-10 production was measured at 48 h. mRNA expression of receptor subunits for IL-23, IL-12 and IL-17 was assessed at 24 h. Both cell activation and interactions were needed for a high IL-17A secretion while IL-17F was stimulated by PHA activation alone and further increased in co-cultures. IL-17F levels were higher than IL-17A in both co-cultures (p < 0.05). IL-17F addition decreased IL-17A secretion (p < 0.05) but IL-17A addition had no effect on IL-17F secretion. Interestingly, IL-17A and IL-17F upregulated IL-17RA and IL-17RC mRNA expression in PBMC/skin fibroblast co-cultures (p < 0.05) while only IL-17F exerted this effect in synoviocytes (p < 0.05). Monocyte exclusion in both co-cultures increased IL-17A and IL-17F (twofold, p < 0.05) while decreasing IL-10 and IL-6 secretion (twofold, p < 0.05). IL-17A and F had differential effects on their receptor expression with a higher sensitivity for skin fibroblasts highlighting the differential contribution of IL-17A and F in joint vs. skin diseases.

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.