Cytokines as biomarkers in rheumatoid arthritis

Synovial 5-Lipoxygenase-Derived Oxylipins Define a Lympho-Myeloid-Enriched Synovium

OBJECTIVE

Oxylipins are bioactive lipids derived from polyunsaturated fatty acids (PUFAs) that modulate inflammation and may remain overexpressed in refractory synovitis. In plasma, they could also be biomarkers of synovial pathology. The aim of this study is to determine if synovial oxylipins in inflamed joints correlate with plasma oxylipins and with synovial histologic patterns.

METHODS

Patients with established rheumatoid or psoriatic arthritis with active disease despite treatment were recruited, and paired synovial tissue (ST) and plasma were collected. Oxylipins were determined by liquid chromatography with tandem mass spectrometry and were classified into groups according to their PUFA precursor and enzyme. The expression of CD20, CD68, CD3, and CD138 was obtained to describe synovial histology. Cell-specific expression of oxylipin-related genes was identified by examining available synovial single-cell RNA sequencing data.

RESULTS

We included a total of 32 ST and 26 paired-plasma samples. A total of 71 oxylipins were identified in ST, but only 24 were identified in plasma. Only levels of 9,10-dihydroxyoctadecenoic acid and tetranor-Prostaglandin FM had a significant positive correlation between plasma and ST. Several oxylipins and oxylipin-related genes were differentially expressed among synovial phenotypes. Specifically, several 5-lipoxygenase (LOX)-derived oxylipins were statistically elevated in the lympho-myeloid phenotype and associated with B cell expression in rheumatoid arthritis samples.

CONCLUSION

The lack of correlation between ST and plasma oxylipins suggests that ST lipid profiling better characterizes active pathways in treated joints. Synovial 5-LOX-derived oxylipins were highly expressed in lympho-myeloid-enriched synovium. Combination therapy with 5-LOX inhibitors to improve refractory inflammation may be needed in patients with this histologic group.

Anti-inflammatory effect of the combined treatment of LMT-28 and kaempferol in a collagen-induced arthritis mouse model

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation and swelling. Several studies have demonstrated that RA fibroblast-like synovial cells (RA-FLS) play an important role in RA pathogenesis. Activated RA-FLS contribute to synovial inflammation by secreting inflammatory cytokines including interleukin (IL)-1β, IL-6 and tumor necrosis factor-α. LMT-28 is derivative of oxazolidone and exerts anti-inflammatory effects on RA via IL-6 signaling pathway regulation. LMT-28 also regulates T cell differentiation in RA condition. However, the effect of LMT-28 on the migration and invasion of RA-FLS remains unknown. Kaempferol has been reported to have pharmacological effects on various diseases, such as inflammatory diseases, autoimmune diseases, and cancer. Additionally, kaempferol has been reported to inhibit RA-FLS migration and invasion, but it is not known about the therapeutic mechanism including molecular mechanism such as receptor. The present study aimed to investigate the synergistic effects of the combined treatment of LMT-28 and kaempferol on RA-FLS activation and RA pathogenesis in mouse model. LMT-28 and kaempferol co-administration inhibited RA disease severity and histological collapse in the joint tissues of CIA mice, as well as downregulated the levels of pro-inflammatory cytokines in mouse serum. Additionally, the combined treatment inhibited excessive differentiation of T helper 17 cells and osteoclasts. Furthermore, compared with single treatments, combined treatment showed enhanced inhibitory effects on the hyperactivation of IL-6-induced signaling pathway in RA-FLS. Combined treatment also inhibited RA-FLS cell proliferation, migration, and invasion and suppressed the expression of matrix metalloproteinase in RA-FLS. Furthermore, we confirmed that the combined treatment inhibited chondrocyte proliferation, migration, and invasion. In conclusion, our results suggest that the combined treatment of LMT-28 and kaempferol exerts a synergistic effect on the RA development via the regulation of IL-6-induced hyperactivation of RA-FLS. Furthermore, this study suggests that combination therapies can be an effective therapeutic option for arthritis.

An overview of multi-omics technologies in rheumatoid arthritis: applications in biomarker and pathway discovery

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease with a complex pathological mechanism involving autoimmune response, local inflammation and bone destruction. Metabolic pathways play an important role in immune-related diseases and their immune responses. The pathogenesis of rheumatoid arthritis may be related to its metabolic dysregulation. Moreover, histological techniques, including genomics, transcriptomics, proteomics and metabolomics, provide powerful tools for comprehensive analysis of molecular changes in biological systems. The present study explores the molecular and metabolic mechanisms of RA, emphasizing the central role of metabolic dysregulation in the RA disease process and highlighting the complexity of metabolic pathways, particularly metabolic remodeling in synovial tissues and its association with cytokine-mediated inflammation. This paper reveals the potential of histological techniques in identifying metabolically relevant therapeutic targets in RA; specifically, we summarize the genetic basis of RA and the dysregulated metabolic pathways, and explore their functional significance in the context of immune cell activation and differentiation. This study demonstrates the critical role of histological techniques in decoding the complex metabolic network of RA and discusses the integration of histological data with other types of biological data.

A synoptic literature review of animal models for investigating the biomechanics of knee osteoarthritis

Osteoarthritis (OA) is a common chronic disease largely driven by mechanical factors, causing significant health and economic burdens worldwide. Early detection is challenging, making animal models a key tool for studying its onset and mechanically-relevant pathogenesis. This review evaluate current use of preclinical in vivo models and progressive measurement techniques for analysing biomechanical factors in the specific context of the clinical OA phenotypes. It categorizes preclinical in vivo models into naturally occurring, genetically modified, chemically-induced, surgically-induced, and non-invasive types, linking each to clinical phenotypes like chronic pain, inflammation, and mechanical overload. Specifically, we discriminate between mechanical and biological factors, give a new explanation of the mechanical overload OA phenotype and propose that it should be further subcategorized into two subtypes, post-traumatic and chronic overloading OA. This review then summarises the representative models and tools in biomechanical studies of OA. We highlight and identify how to develop a mechanical model without inflammatory sequelae and how to induce OA without significant experimental trauma and so enable the detection of changes indicative of early-stage OA in the absence of such sequelae. We propose that the most popular post-traumatic OA biomechanical models are not representative of all types of mechanical overloading OA and, in particular, identify a deficiency of current rodent models to represent the chronic overloading OA phenotype without requiring intraarticular surgery. We therefore pinpoint well standardized and reproducible chronic overloading models that are being developed to enable the study of early OA changes in non-trauma related, slowly-progressive OA. In particular, non-invasive models (repetitive small compression loading model and exercise model) and an extra-articular surgical model (osteotomy) are attractive ways to present the chronic natural course of primary OA. Use of these models and quantitative mechanical behaviour tools such as gait analysis and non-invasive imaging techniques show great promise in understanding the mechanical aspects of the onset and progression of OA in the context of chronic knee joint overloading. Further development of these models and the advanced characterisation tools will enable better replication of the human chronic overloading OA phenotype and thus facilitate mechanically-driven clinical questions to be answered.

Does the nurse-led case management benefit rheumatoid arthritis patients in reducing distressing symptoms and C-reactive protein: a 2-year follow-up study in Taiwan

Background

Rheumatoid arthritis (RA) is a chronic disease and may worsen over time. Today, nurse-led case management (NLCM) has been recommended to improve clinical outcomes for chronic disease patients, yet little is known regarding its impact on pain, fatigue, and C-reactive protein (CRP) among RA patients. We aimed to explore this issue among such groups via a two-group pre- and post-test approach.

Methods

All subjects were recruited from one hospital in Taiwan from January 2017 to June 2018 and assigned to either a 6-month NLCM program in addition to usual care or to a control group that received usual care only. All of them were followed for 2 years. Outcomes of interests were compared at four time points: baseline, the third day after NLCM completion, and at 6 and 24 months after NLCM. Effects between them were tested using the generalized estimating equations (GEE) model after adjusting for differences at baseline.

Results

A total of 50 patients in the NLCM group and 46 in the control group were recruited for data analysis. Results from the GEE model indicated that integrating NLCM into conventional care benefited patients in decreasing levels of pain and fatigue, as well as CRP value. These improvements were still observed for 2 years after NLCM.

Conclusion

NLCM was shown to be helpful in lowering pain, fatigue, and CRP, which implies that NLCM may be a reference in the provision of tailored care for those affected by rheumatism.

Interleukin 27, like interferons, activates JAK-STAT signaling and promotes pro-inflammatory and antiviral states that interfere with dengue and chikungunya viruses replication in human macrophages

Interferons (IFNs) are a family of cytokines that activate the JAK-STAT signaling pathway to induce an antiviral state in cells. Interleukin 27 (IL-27) is a member of the IL-6 and/or IL-12 family that elicits both pro- and anti-inflammatory responses. Recent studies have reported that IL-27 also induces a robust antiviral response against diverse viruses, both in vitro and in vivo, suggesting that IFNs and IL-27 share many similarities at the functional level. However, it is still unknown how similar or different IFN- and IL-27-dependent signaling pathways are. To address this question, we conducted a comparative analysis of the transcriptomic profiles of human monocyte-derived macrophages (MDMs) exposed to IL-27 and those exposed to recombinant human IFN-α, IFN-γ, and IFN-λ. We utilized bioinformatics approaches to identify common differentially expressed genes between the different transcriptomes. To verify the accuracy of this approach, we used RT-qPCR, ELISA, flow cytometry, and microarrays data. We found that IFNs and IL-27 induce transcriptional changes in several genes, including those involved in JAK-STAT signaling, and induce shared pro-inflammatory and antiviral pathways in MDMs, leading to the common and unique expression of inflammatory factors and IFN-stimulated genes (ISGs)Importantly, the ability of IL-27 to induce those responses is independent of IFN induction and cellular lineage. Additionally, functional analysis demonstrated that like IFNs, IL-27-mediated response reduced chikungunya and dengue viruses replication in MDMs. In summary, IL-27 exhibits properties similar to those of all three types of human IFN, including the ability to stimulate a protective antiviral response. Given this similarity, we propose that IL-27 could be classified as a distinct type of IFN, possibly categorized as IFN-pi (IFN-π), the type V IFN (IFN-V).

Higher Synovial Immunohistochemistry Reactivity of IL-17A, Dkk1, and TGF-β1 in Patients with Early Psoriatic Arthritis and Rheumatoid Arthritis Could Predict the Use of Biologics

BACKGROUND

Delay in diagnosis and therapy in patients with arthritis commonly leads to progressive articular damage. The study aimed to investigate the immunohistochemical reactivity of synovial cytokines associated with inflammation and the bone erosives/neoformatives processes among individuals diagnosed with psoriatic arthritis (PsA), rheumatoid arthritis (RA), osteoarthritis (OA), and radiographic axial spondyloarthritis (r-axSpA), with the intention of identifying potential biomarkers.

METHODS

Specimens were collected from the inflamed knee joints of patients referred for arthroscopic procedures, and the synovial tissue (ST) was prepared for quantifying protein expression through immunohistochemical analysis (% expressed in Ratio_Area-Intensity) for TGF-β1, IL-17A, Dkk1, BMP2, BMP4, and Wnt5b. The collected data underwent thorough analysis and examination of their predictive capabilities utilising receiver operating characteristic (ROC) curves.

RESULTS

Valid synovial tissue samples were acquired from 40 patients for IHC quantification analysis. Initially, these patients had not undergone treatment with biologics. However, after 5 years, 4 out of 13 patients diagnosed with PsA and two out of nine patients diagnosed with RA had commenced biologic treatments. Individuals with early PsA who received subsequent biologic treatment exhibited significantly elevated IHC reactivity in ST for TGF-β1 (p = 0.015). Additionally, patients with both PsA and RA who underwent biologic therapy displayed increased IHC reactivity for IL-17A (p = 0.016), TGF-β1 (p = 0.009), and Dkk1 (p = 0.042). ROC curve analysis of IHC reactivity for TGF-β1, Dkk1, and IL-17A in the synovial seems to predict future treatment with biologics in the next 5 years with the area under the curve (AUC) of a combined sum of the three values: AUC: 0.828 (95% CI: 0.689-0.968; p 0.005) S 75% E 84.4%.

CONCLUSIONS

Higher synovial immunohistochemistry reactivity of IL-17A, Dkk1, and TGF-β1 in patients with early psoriatic arthritis and rheumatoid arthritis may serve as potential indicators for predicting the necessity of utilising biologic treatments.

The protective effects of Phoenixin-20 in tumor necrosis factor α (TNF-α)-induced cell senescence of rheumatoid arthritis fibroblast-like synoviocytes (FLS)

Rheumatoid arthritis (RA) is an age-related joint destruction disease that markedly impacts the normal life of patients. Currently, the clinical treatment strategies are far from satisfactory with severe side effects. Cellular senescence of fibroblast-like synoviocytes (FLS) has been reported to be involved in the pathological process of arthritis, which may provide an important research direction for RA treatment. Phoenixin-20 (PNX-20) is a peptide targeting G-protein-coupled receptor 173 (GPR173) with promising anti-inflammatory properties. Our study will probe into the function of PNX-20 on tumor necrosis factor α (TNF-α)- induced rheumatoid arthritis (RA) FLS cell senescence to provide a theoretical basis for treating RA with PNX-20. RA-FLSs were handled with 10 ng/mL TNF-α, followed by introducing Phoenixin-20 (10, 20 nM) or not for 7 days. Enhanced release of inflammatory cytokines, increased proportion of senescence-associated β-galactosidase (SA-β-gal) positive cells, and declined telomerase activity were all observed in TNF-α-treated RA-FLSs, accompanied by a noticeable decline in the p21 and p53 level, which were notably reversed by 10 and 20 nM PNX-20. Furthermore, the increased signal transducer and activator of transcription 6 (STAT6) level observed in TNF-α-treated RA-FLSs were signally repressed by PNX-20. Moreover, the impact of PNX-20 on TNF-α-induced cellular senescence in RA-FLSs was abrogated by the overexpression of STAT6. Collectively, PNX-20 protected the TNF-α-induced cell senescence in RA-FLSs by downregulating STAT6. Based on these findings, we speculate that PNX-20 might be a promising agent for the treatment of RA.

Effect of acupuncture on arthritic pathological injury in rats with type Ⅱ collagen-induced rheumatoid arthritis

OBJECTIVES

To observe the effect of acupuncture stimulation of "Yanglingquan"(GB34), "Zusanli"(ST36) and "Xuanzhong" (GB39) on arthritis index (AI), joint synovial membrane pathology, serum-related immunoinflammatory factors, and expressions of tumor suppressor gene mt-p53, nuclear factor kappa B (NF-κB) and peroxisome proliferator activated receptor gamma (PPARγ) in knee joint synovial tissue of rats with type Ⅱ collagen-induced arthritis (CIA), so as to explore its possible mechanisms underlying improvement of rheumatoid arthritis (RA).

METHODS

Male SD rats were used in the present study. The CIA model was established by subcutaneous injection of collagen emulsion (200 μL/rat) in the tail root region on the first day and repeat (100 μL/rat) once on the 9th day. Eighteen successful CIA rats were randomized into model, medication and acupuncture groups, with 6 rats in each group. Other 6 normal rats were used as the normal control group. For rats of the medication group, leflunomide (1.9 mg/kg) was administrated by gavage, once a day, and for rats of the acupuncture group, manual acupuncture stimulation was applied to bilateral GB34, ST36, GB39 for 30 min, once a day, for 12 weeks. The arthritis index (AI) score (0-4 points) was evaluated once every week. The contents of IL-6, IL-17 and TNF-α in the serum were determined by ELISA. Histopathological changes of the ankle joint were observed by H.E. staining. The protein and mRNA expression levels of mt-p53, NF-κB p65, and PPARγ in the knee joint synovial tissue were determined by Western blot and quantitative real time PCR, separately.

RESULTS

Compared with the normal control group, the AI scores at different time-points after modeling, contents of serum TNF-α, IL-6 and IL-17, expression levels of mt-p53, NF-κB p65, PPARγ proteins and mRNAs were significantly increased in the model group (P<0.01, P<0.05). In comparison with the model group, the AI scores at the 10th week in the medication group and at the 3rd, 9th and 10th week in the acupuncture group, contents of serum TNF-α, IL-6 and IL-17, and the expression levels of mt-p53 and NF-κB p65 proteins in both medication and acupuncture groups, as well as mt-p53 and NF-κB p65 mRNAs in the medication group were apparently decreased (P<0.01, P<0.05), while the expression levels of PPARγ protein in both medication and acupuncture group and PPARγ mRNA in the medication group were significantly up-regulated (P<0.05, P<0.01). No significant differences were found between the acupuncture and medication groups in down-regulating the AI score and serum TNF-α, IL-6 and IL-17 contents. The effect of acupuncture was weaker than that of medication in down-regulating the expression of mt-p53 and NF-κB p65 proteins and mRNAs and in up-regulating PPARγ mRNA (P<0.01). H.E. results showed ankle cartilage hyperplasia, reduced joint cavity, mild fibroproliferation and inflammatory cell infiltration in the surrounding soft tissue of the ankle joint in rats of the model group, which was milder in both medication and acupuncture groups.

CONCLUSIONS

Acupuncture stimulation can improve the degree of joint inflammation and swelling in CIA rats, which may be related to its effects in inhibiting the overexpression of immunoinflammatory factors in serum and regulating expression of mt-p53, NF-κB p65, PPARγ mRNAs and proteins in the synovial tissue.

Evaluating the effect of ursodeoxycholic acid (UDCA) in comparison with dexamethasone and diclofenac in a rat model of rheumatoid arthritis

Ursodeoxycholic acid (UDCA) is known for its major effects on the liver, but its impact on autoimmune diseases is not well understood. This study aimed to assess the effectiveness of UDCA in controlling rheumatoid arthritis (RA) in an in vivo setting. Experimental RA was induced in rats using Freund's complete adjuvant, and the effects of UDCA (50,100 mg/kg) were compared to those of dexamethasone and diclofenac by measuring changes in paw size, IL-17, pro-inflammatory cytokines, oxidative stress (GSH, MDA), and radiological changes. The administration of UDCA resulted in decreased cartilage damage, reduced paw edema, and a decrease in the release of pro-inflammatory cytokines and oxidative stress. Additionally, X-ray joint alterations were observed in the UDCA-treated group compared to the dexamethasone and diclofenac groups. These results suggest that UDCA has anti-rheumatoid arthritis properties due to its ability to minimize oxidative stress and inflammation in arthritis-affected rats.

The Fidelity of Rheumatoid Arthritis Multivariate Diagnostic Biomarkers Using Discriminant Analysis and Binary Logistic Regression

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease that causes multi-articular synovitis. The illness is characterized by worsening inflammatory synovitis, which causes joint swelling and pain. Synovitis erodes articular cartilage and marginal bone, resulting in joint deterioration. This bone injury is expected to be permanent. Cytokines play a prominent role in the etiology of RA and could be useful as early diagnostic biomarkers. This research was carried out at Riyadh's King Khalid University Hospital (KKUH). Patients were enrolled from the Rheumatology unit. Seventy-eight RA patients were recruited (67 (85.9%) females and 11 (14.1%) males). Patients were selected for participation by convenience sampling. Demographic data were collected, and disease activity measurements at 28 joints were recorded using the disease activity score (DAS-28). Age- and sex-matched controls from the general population were included in the study. A panel of 27 cytokines, chemokines, and growth factors was determined in patient and control sera. Binary logistic regression (BLR) and discriminant analysis (DA) were used to analyze the data. We show that multiple cytokine biomarker profiles successfully distinguished RA patients from healthy controls. IL-17, IL-4, and RANTES were among the most predictive variables and were the only biomarkers incorporated into both BLR and DA predictive models for pooled participants (men and women). In the women-only models, the significant cytokines incorporated in the model were IL-4, IL-17, MIP-1b, and RANTES for the BLR model and IL-4, IL-1Ra, GM-CSF, IL-17, and eotaxin for the DA model. The BLR and DA men-only models contained one cytokine each, eotaxin for BLR and platelet-derived growth factor-bb (PDGF-BB) for DA. We show that BLR has a higher fidelity in identifying RA patients than DA. We also found that the use of gender-specific models marginally improves detection fidelity, indicating a possible benefit in clinical diagnosis. More research is needed to determine whether this conclusion will hold true in various and larger patient populations.

Serum Cytokine Profiles in Patients with Rheumatoid Arthritis Before and After Treatment with Methotrexate

Rheumatoid arthritis (RA) is an inflammatory autoimmune illness affecting around 1% of the population globally. Cytokines have a crucial role in the pathogenesis of RA. The objectives of the present study were to compare the serum cytokine profiles between methotrexate (MTX)-treated and MTX-naive RA patient groups, MTX-treated RA patient group and healthy controls, and MTX-naive RA patient group and healthy controls. Enzyme linked immunosorbent assay (ELISA) kits were used to quantify the serum concentrations of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-17, IL-6, interferon-gamma (IFN-γ), and IL-10 in 80 RA patients (48 MTX treated and 32 MTX naive) and 80 healthy controls. For all cytokine assays, absorbance was measured at 450 nm using a microplate reader (Bio-Rad). Independent sample t-test was used to compare the serum cytokine concentrations between the study groups using SPSS version 25. MTX-treated RA patient group had significantly reduced serum levels of TNF-α (36.13 ± 17.64 versus 45.82 ± 23.07, *P = 0.037), IL-17 (307.85 ± 151.74 versus 435.42 ± 241.19, **P = 0.006), and IFN-γ (414.93 ± 212.13 versus 527.15 ± 269.61, *P = 0.041) compared to MTX-naive RA patients. Both MTX-treated and MTX-naive RA patient groups had significantly high serum levels of TNF-α, IL-1β, IL-17, IL-6, IFN-γ, and IL-10 when compared to healthy controls (***P < 0.001). Downregulation of the serum concentrations of certain key cytokines, viz. TNF-α, IL-17, and IFN-γ, demonstrates the anti-inflammatory effect of MTX in RA patients.

Can pyroptosis be a new target in rheumatoid arthritis treatment?

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease of undefined etiology, with persistent synovial inflammation and destruction of articular cartilage and bone. Current clinical drugs for RA mainly include non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, disease modifying anti-rheumatic drugs (DMARDs) and so on, which can relieve patients' joint symptoms. If we want to have a complete cure for RA, there are still some limitations of these drugs. Therefore, we need to explore new mechanisms of RA to prevent and treat RA radically. Pyroptosis is a newly discovered programmed cell death (PCD) in recent years, which is characterized by the appearance of holes in cell membranes, cell swelling and rupture, and the release of intracellular pro-inflammatory factors into the extracellular space, resulting in a strong inflammatory response. The nature of pyroptosis is pro-inflammatory, and whether it is participating in the development of RA has attracted a wide interest among scholars. This review describes the discovery and mechanism of pyroptosis, the main therapeutic strategies for RA, and the role of pyroptosis in the mechanism of RA development. From the perspective of pyroptosis, the study of new mechanisms of RA may provide a potential target for the treatment of RA and the development of new drugs in the clinics.

Transcriptome analysis of human macrophages upon chikungunya virus (CHIKV) infection reveals regulation of distinct signaling and metabolic pathways during the early and late stages of infection

Macrophages are efficient reservoirs for viruses that enable the viruses to survive over a longer period of infection. Alphaviruses such as chikungunya virus (CHIKV) are known to persist in macrophages even after the acute febrile phase. The viral particles replicate in macrophages at a very low level over extended period of time and are localized in tissues that are often less accessible by treatment. Comprehensive experimental studies are thus needed to characterize the CHIKV-induced modulation of host genes in these myeloid lineage cells and in one such pursuit, we obtained global transcriptomes of a human macrophage cell line infected with CHIKV, over its early and late timepoints of infection. We analyzed the pathways, especially immune related, perturbed over these timepoints and observed several host factors to be differentially expressed in infected macrophages in a time-dependent manner. We postulate that these pathways may play crucial roles in the persistence of CHIKV in macrophages.

A Novel Hydroxyapatite/Vitamin B12 Nanoformula for Treatment of Bone Damage: Preparation, Characterization, and Anti-Arthritic, Anti-Inflammatory, and Antioxidant Activities in Chemically Induced Arthritic Rats

The usage of nanomaterials for rheumatoid arthritis (RA) treatment can improve bioavailability and enable selective targeting. The current study prepares and evaluates the in vivo biological effects of a novel hydroxyapatite/vitamin B₁₂ nanoformula in Complete Freund's adjuvant-induced arthritis in rats. The synthesized nanoformula was characterized using XRD, FTIR, BET analysis, HERTEM, SEM, particle size, and zeta potential. We synthesized pure HAP NPs with 71.01% loading weight percentages of Vit B12 and 49 mg/g loading capacity. Loading of vitamin B₁₂ on hydroxyapatite was modeled by Monte Carlo simulation. Anti-arthritic, anti-inflammatory, and antioxidant effects of the prepared nanoformula were assessed. Treated arthritic rats showed lower levels of RF and CRP, IL-1β, TNF-α, IL-17, and ADAMTS-5, but higher IL-4 and TIMP-3 levels. In addition, the prepared nanoformula increased GSH content and GST antioxidant activity while decreasing LPO levels. Furthermore, it reduced the expression of TGF-β mRNA. Histopathological examinations revealed an improvement in joint injuries through the reduction of inflammatory cell infiltration, cartilage deterioration, and bone damage caused by Complete Freund's adjuvant. These findings indicate that the anti-arthritic, antioxidant, and anti-inflammatory properties of the prepared nanoformula could be useful for the development of new anti-arthritic treatments.

Evaluation of serum Interleukin 36 in Iraqi patients with Rheumatoid arthritis

Rheumatoid arthritis is a worldwide inflammatory chronic autoimmune disease with varying severity. Due to no definitive cure for this disease, current therapies aim to decrease the pain and slow further damage. The interleukin (IL)‐36 cytokine was little known for its role in rheumatoid arthritis; this research aimed to evaluate the serum IL36 levels in RA patients compared to healthy controls. This study included 80 patients with rheumatoid arthritis registered at the Rheumatology Clinic in Baghdad teaching hospital. The patients were divided into three groups based on the treatments received. Group 1 included patients treated with biological therapy (etanercept, adalimumab), Group2 patients with non-biological treatment (methotrexate hydroxychloroquine and prednisone), Group3 patients without any treatment and compared with Group 4 healthy control group. Patients is all groups were assessed for their serum IL-36 concentration; the mean IL-36 serum level was significantly higher in three groups of RA patients which include the group of patients treated with biological therapy (Enbrel (etanercept) and Humira (adalimumab) means were (1132.41±475.2,), and group of non-biological therapy patients (Methotrexate hydroxychloroquine and prednisone) (G2) means was 553.95±307, than patients' group without any treatment (G3) means was 1044.01±575.3 compared to the control (341.38±113.1) p-value> 0.00001. The patient's age and BMI were not significantly different between three groups of patient Rheumatoid arthritis. Parameters for this disease also were tested which include RF, CRP, ESR, anti-CCP and disease activity score-28 (DAS 28), there were significant differences when compared with the control group. IL-36 serum level was significantly higher in three groups of rheumatoid arthritis than those in controls, and when compared between three patients groups there was less concentration in the non-biological therapy treatment group means was 553.95±307 than in the rest of the patient groups,biology tratment, without any treatment, means were (1132.41±475.2, 1044.01±575.3) respectively. This study found that Rheumatoid arthritis patients' serum IL36 levels increased, where a non-biologic therapies reduced this cytokine. IL-36's pathogenic involvement in Rheumatoid arthritis needs more study. Keywords: Rheumatoid arthritis, IL-36, IL-1,C‐reactive protein, RF, ESR and anti-CCP.

Rheumatoid arthritis and non-coding RNAs; how to trigger inflammation

Rheumatoid arthritis (RA) is a systemic and chronic inflammatory disease categorized by continuous synovitis in the joints and systemic inflammatory responses that can cause lifelong disability. The major cause of RA is the dysregulation of the immune response. The development of RA disease includes multiplex association of several interleukins and cells, which leads to synovial cell growth, cartilage and bone damage. The primary stage of RA disease is related to the modification of both the innate and adaptive immune systems, which leads to the formation of autoantibodies. This process results in many damaged molecules and epitope spreading. Both the innate (e.g., dendritic cells, macrophages, and neutrophils) and acquired immune cells (e.g., T and B lymphocytes) will increase and continue the chronic inflammatory condition in the next stages of the RA disease. In recent years, non-coding RNAs have been proved as significant controllers of biological functions, especially immune cell expansion and reactions. Non-coding RNAs were primarily containing microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA). Various studies confirmed non-coding RNAs as hopeful markers for diagnosing and curing RA. This review will describe and cover existing knowledge about RA pathogenesis, which might be favorable for discovering possible ncRNA markers for RA.

Using human genetics to improve safety assessment of therapeutics

Human genetics research has discovered thousands of proteins associated with complex and rare diseases. Genome-wide association studies (GWAS) and studies of Mendelian disease have resulted in an increased understanding of the role of gene function and regulation in human conditions. Although the application of human genetics has been explored primarily as a method to identify potential drug targets and support their relevance to disease in humans, there is increasing interest in using genetic data to identify potential safety liabilities of modulating a given target. Human genetic variants can be used as a model to anticipate the effect of lifelong modulation of therapeutic targets and identify the potential risk for on-target adverse events. This approach is particularly useful for non-clinical safety evaluation of novel therapeutics that lack pharmacologically relevant animal models and can contribute to the intrinsic safety profile of a drug target. This Review illustrates applications of human genetics to safety studies during drug discovery and development, including assessing the potential for on- and off-target associated adverse events, carcinogenicity risk assessment, and guiding translational safety study designs and monitoring strategies. A summary of available human genetic resources and recommended best practices is provided. The challenges and future perspectives of translating human genetic information to identify risks for potential drug effects in preclinical and clinical development are discussed.

ASPS Exhibits Anti-Rheumatic Effects by Reprogramming Gut Microbiota and Increasing Serum γ-Glutamylcysteine Level

Rheumatoid arthritis (RA) is an essential cause of labor loss and disability for people worldwide. Acanthopanax senticosus polysaccharide (ASPS) is one of the most important active components from A. senticosus, which exhibits various pharmacological activities such as antioxidation and immunomodulation. However, no studies have reported the application of ASPS in treating RA. This study aims to investigate the therapeutic effect of ASPS on RA and reveal its underlying mechanism. The potential therapeutic effect of ASPS against RA is initially verified in this study using the collagen-induced arthritis model. Moreover, the protective benefits of ASPS are transmitted through the fecal microbiota and blocked by simultaneous antibiotic cocktail treatment, indicating that gut microbiota may be correlated with ASPS. The 16S rRNA sequencing using feces samples and untargeted UPLC-MS metabolomics using serum samples further reveal that ASPS reprograms the arthritic progression triggered dysbiosis, enhances the expression of γ-glutamylcysteine (GGC) synthetase, and enriches the serum concentration of GGC. Furthermore, metabolites GGC is found to be able to effectively interrupt NLRP3 inflammasome activation via inhibiting ASC nucleation and therefore attenuate inflammatory arthritis. Taken together, this work highlights ASPS's therapeutic potential against RA, which mainly exhibits its effects via modulating gut microbiota and regulating GGC production.

Absent in melanoma 2 (AIM2) in rheumatoid arthritis: novel molecular insights and implications

Absent in melanoma 2 (AIM2), a member of the Pyrin and HIN domain protein family, is a cytoplasmic receptor that recognizes double-stranded DNA. AIM2 exhibits limited expression under physiological conditions but is widely expressed in many human diseases, including autoimmune diseases, and plays an essential role in the immune response. Rheumatoid arthritis (RA) is an autoimmune disease that poses a severe threat to physical and mental health, and is caused by several genetic and metabolic factors. Multiple immune cells interact to form a complex inflammatory network that mediates inflammatory responses and bone destruction. Abnormal AIM2 expression in multiple immune cell populations (T cells, B cells, fibroblast-like synoviocytes, monocytes, and macrophages) may regulate multiple functional responses in RA through mechanisms such as pyroptosis, PANoptosis, and regulation of other molecules. In this review, we describe and summarize the functional regulation and impact of AIM2 expression in immune cells to improve our understanding of the complex pathological mechanisms. These insights may provide potential directions for the development of new clinical diagnostic strategies for RA.

SARS-CoV-2 induces "cytokine storm" hyperinflammatory responses in RA patients through pyroptosis

Background

The coronavirus disease (COVID-19) is a pandemic disease that threatens worldwide public health, and rheumatoid arthritis (RA) is the most common autoimmune disease. COVID-19 and RA are each strong risk factors for the other, but their molecular mechanisms are unclear. This study aims to investigate the biomarkers between COVID-19 and RA from the mechanism of pyroptosis and find effective disease-targeting drugs.

Methods

We obtained the common gene shared by COVID-19, RA (GSE55235), and pyroptosis using bioinformatics analysis and then did the principal component analysis(PCA). The Co-genes were evaluated by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and ClueGO for functional enrichment, the protein-protein interaction (PPI) network was built by STRING, and the k-means machine learning algorithm was employed for cluster analysis. Modular analysis utilizing Cytoscape to identify hub genes, functional enrichment analysis with Metascape and GeneMANIA, and NetworkAnalyst for gene-drug prediction. Network pharmacology analysis was performed to identify target drug-related genes intersecting with COVID-19, RA, and pyroptosis to acquire Co-hub genes and construct transcription factor (TF)-hub genes and miRNA-hub genes networks by NetworkAnalyst. The Co-hub genes were validated using GSE55457 and GSE93272 to acquire the Key gene, and their efficacy was assessed using receiver operating curves (ROC); SPEED2 was then used to determine the upstream pathway. Immune cell infiltration was analyzed using CIBERSORT and validated by the HPA database. Molecular docking, molecular dynamics simulation, and molecular mechanics-generalized born surface area (MM-GBSA) were used to explore and validate drug-gene relationships through computer-aided drug design.

Results

COVID-19, RA, and pyroptosis-related genes were enriched in pyroptosis and pro-inflammatory pathways(the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome complex, death-inducing signaling complex, regulation of interleukin production), natural immune pathways (Network map of SARS-CoV-2 signaling pathway, activation of NLRP3 inflammasome by SARS-CoV-2) and COVID-19-and RA-related cytokine storm pathways (IL, nuclear factor-kappa B (NF-κB), TNF signaling pathway and regulation of cytokine-mediated signaling). Of these, CASP1 is the most involved pathway and is closely related to minocycline. YY1, hsa-mir-429, and hsa-mir-34a-5p play an important role in the expression of CASP1. Monocytes are high-caspase-1-expressing sentinel cells. Minocycline can generate a highly stable state for biochemical activity by docking closely with the active region of caspase-1.

Conclusions

Caspase-1 is a common biomarker for COVID-19, RA, and pyroptosis, and it may be an important mediator of the excessive inflammatory response induced by SARS-CoV-2 in RA patients through pyroptosis. Minocycline may counteract cytokine storm inflammation in patients with COVID-19 combined with RA by inhibiting caspase-1 expression.

IL-31 and IL-33 in rheumatoid arthritis patients

Objective – to investigate clinical and diagnostic significance of IL-31 and IL-33 determination in patients with rheumatoid arthritis (RA).

Material and methods. 154 patients with a reliable diagnosis of RA were examined. Serum levels of IL-31 and IL-33 were studied using multiplex xMAP technology on Bio-PlexTM 200 System analyzer (BIO-RAD, USA). The upper limit of the norm in the study of 20 healthy donor sera was (M+3σ): IL-31 – 15.08 pg/ml, IL-33 – 3.40 pg/ml.

Results. IL-31 (Me (25th; 75th percentile) – 13.75 (5.63; 308.52) and 6.10 (2.87; 8.62) pg/ml (p<0.001), IL-33 – 18.86 (7.45; 65.95) and 0.52 (0.17; 0.78) pg/ml (p><0.001) levels were observed in RA patients in comparison with the control group. An increase in IL-33 concentration (more than 3.40 pg/ml) was observed in 87.0% of patients, and IL-31 (more than 15.08 pg/ml) in 48.1% of patients with RA. An increase in IL-33 alone was observed in 42.2% (65 of 154 patients) with RA, while an isolated increase in IL-31 concentration was observed in only 2 (1.3%) patients. Simultaneous hyperproduction of IL-33 and IL-31 occurred in 69 (44.9%) patients. We revealed positive correlation of clinical and laboratory parameters of RA with cytokine concentration: SDAI correlated with IL-33 (r=0.36; p><0.05); CRP – with IL-31 (r=0.49; p><0,05) and IL-33 (r=0.40; p><0.05). Conclusion. Concentrations of IL-31 and IL-33 are elevated in RA patients and correlate with the indices of inflammatory activity of the disease.>< 0.001), IL-33 – 18.86 (7.45; 65.95) and 0.52 (0.17; 0.78) pg/ml (p<0.001) levels were observed in RA patients in comparison with the control group. An increase in IL-33 concentration (more than 3.40 pg/ml) was observed in 87.0% of patients, and IL-31 (more than 15.08 pg/ml) in 48.1% of patients with RA. An increase in IL-33 alone was observed in 42.2% (65 of 154 patients) with RA, while an isolated increase in IL-31 concentration was observed in only 2 (1.3%) patients. Simultaneous hyperproduction of IL-33 and IL-31 occurred in 69 (44.9%) patients. We revealed positive correlation of clinical and laboratory parameters of RA with cytokine concentration: SDAI correlated with IL-33 (r=0.36; p><0.05); CRP – with IL-31 (r=0.49; p><0,05) and IL-33 (r=0.40; p><0.05). Conclusion. Concentrations of IL-31 and IL-33 are elevated in RA patients and correlate with the indices of inflammatory activity of the disease.>< 0.001) levels were observed in RA patients in comparison with the control group. An increase in IL-33 concentration (more than 3.40 pg/ml) was observed in 87.0% of patients, and IL-31 (more than 15.08 pg/ml) in 48.1% of patients with RA. An increase in IL-33 alone was observed in 42.2% (65 of 154 patients) with RA, while an isolated increase in IL-31 concentration was observed in only 2 (1.3%) patients. Simultaneous hyperproduction of IL-33 and IL-31 occurred in 69 (44.9%) patients. We revealed positive correlation of clinical and laboratory parameters of RA with cytokine concentration: SDAI correlated with IL-33 (r=0.36; p<0.05); CRP – with IL-31 (r=0.49; p><0,05) and IL-33 (r=0.40; p><0.05). Conclusion. Concentrations of IL-31 and IL-33 are elevated in RA patients and correlate with the indices of inflammatory activity of the disease.>< 0.05); CRP – with IL-31 (r=0.49; p< ,05) and IL-33 (r=0.40; p<0.05)

Conclusion. Concentrations of IL-31 and IL-33 are elevated in RA patients and correlate with the indices of inflammatory activity of the disease.

A high-throughput screening RT-qPCR assay for quantifying surrogate markers of immunity from PBMCs

Immunoassays that quantitate cytokines and other surrogate markers of immunity from peripheral blood mononuclear cells (PBMCs), such as flow cytometry or Enzyme-Linked Immunosorbent Spot (ELIspot), allow highly sensitive measurements of immune effector function. However, those assays consume relatively high numbers of cells and expensive reagents, precluding comprehensive analyses and high-throughput screening (HTS). To address this issue, we developed a sensitive and specific reverse transcription-quantitative PCR (RT-qPCR)-based HTS assay, specifically designed to quantify surrogate markers of immunity from very low numbers of PBMCs. We systematically evaluated the volumes and concentrations of critical reagents within the RT-qPCR protocol, miniaturizing the assay and ultimately reducing the cost by almost 90% compared to current standard practice. We assessed the suitability of this cost-optimized RT-qPCR protocol as an HTS tool and determined the assay exceeds HTS uniformity and signal variance testing standards. Furthermore, we demonstrate this technique can effectively delineate a hierarchy of responses from as little as 50,000 PBMCs stimulated with CD4⁺ or CD8⁺ T cell peptide epitopes. Finally, we establish that this HTS-optimized protocol has single-cell analytical sensitivity and a diagnostic sensitivity equivalent to detecting 1:10,000 responding cells (i.e., 100 Spot Forming Cells/10⁶ PBMCs by ELIspot) with over 90% accuracy. We anticipate this assay will have widespread applicability in preclinical and clinical studies, especially when samples are limited, and cost is an important consideration.

Identification of SLAMF1 as an immune-related key gene associated with rheumatoid arthritis and verified in mice collagen-induced arthritis model

Background

Rheumatoid arthritis (RA) is the most common inflammatory arthropathy. Immune dysregulation was implicated in the pathogenesis of RA. Thus, the aim of the research was to determine the immune related biomarkers in RA.

Methods

We downloaded the gene expression data of RA in GSE89408 and GSE45291 from Gene Expression Omnibus public database (GEO). Differentially expressed genes (DEGs) were identified between RA and control groups. Infiltrating immune cells related genes were obtained by ssGSEA and weighted gene co-expression network analysis (WGCNA). We performed functional enrichment analysis of differentially expressed immunity-related genes (DEIRGs) by “clusterProfiler” R package, key genes screening by protein-protein interaction (PPI) network of DEIRGs. And mice collagen-induced arthritis (CIA) model was employed to verify these key genes.

Results

A total of 1,885 up-regulated and 1,899 down-regulated DEGs were identified in RA samples. The ssGSEA analysis showed that the infiltration of 25 cells was significantly different. 603 immune related genes were obtained by WGCNA, and 270 DEIRGs were obtained by taking the intersection of DEGs and immune related genes. Enrichment analyses indicated that DEIRGs were associated with immunity related biological processes. 4 candidate biomarkers (CCR7, KLRK1, TIGIT and SLAMF1) were identified from the PPI network of DEIRGs and literature research.

In mice CIA model, the immunohistochemical stain showed SLAMF1 has a significantly high expression in diseased joints. And flow cytometry analysis shows the expression of SLAMF1 on CIA mice-derived CTL cells, Th, NK cells, NKT cells, classical dendritic cell (cDCs) and monocytes/macrophages was also significantly higher than corresponding immune cells from HC mice.

Conclusion

Our study identified SMLAF1 as a key biomarker in the development and progression of RA, which might provide new insight for exploring the pathogenesis of RA.

Platelet-Rich Fibrin Reduces IL-1β Release from Macrophages Undergoing Pyroptosis

Background: Pyroptosis is a catabolic process relevant to periodontal disorders for which interleukin-1β (IL-1β) inflammation is central to the pathophysiology of the disease. Despite platelet-rich fibrin (PRF) anti-inflammatory properties and its application to support periodontal regeneration, the capacity of PRF to modulate pyroptosis, specifically the production and release of IL-1β, remains unknown. The question arises whether PRF could regulate IL-1β release from macrophages in vitro. Methods: To answer this question, RAW 264.7 macrophages and primary macrophages obtained from murine bone marrow were primed with PRF before being challenged by lipopolysaccharide (LPS). Cells were then analysed for the pyroptosis signalling components by gene expression analyses and IL-1β secretion at the protein level. The release of mitochondrial reactive oxygen species (ROS) was also detected. Results: PRF lowered the LPS-induced expression of IL-1β and NLRP3 inflammasome, caspase-11 and IL-18 in primary macrophages, and IL-1β and caspase-11 in RAW 264.7 cells. Additionally, PRF diminished the secretion of IL-1β at the protein level in LPS-induced RAW 264.7 cells. This was shown through immunoassays performed with the supernatant and further confirmed by analysing the lysates of permeabilised cells. Furthermore, PRF reduced the ROS release provoked by LPS in RAW 264.7 cells. Finally, to enhance IL-1β release from the LPS-primed macrophages, we introduced a second signal with adenosine triphosphate (ATP). In this setting, PRF significantly reduced IL-1β release in RAW 264.7 cells and a trend to diminish IL-1β release in primary macrophages. Conclusion: These findings suggest that PRF can reduce IL-1β release and, at least in part, inhibit pyroptosis-related factors in LPS-challenged macrophages.

C1QTNF6 regulated by miR-29a-3p promotes proliferation and migration in stage I lung adenocarcinoma

OBJECTIVE

C1QTNF6 has been implicated as an essential component in multiple cellular and molecular preliminary event, including inflammation, glucose metabolism, endothelial cell modulation and carcinogenesis. However, the biological process and potential mechanism of C1QTNF6 in lung adenocarcinoma (LUAD) are indefinite and remain to be elucidated. Therefore, we investigated the interaction among the traits of C1QTNF6 and LUAD pathologic process.

METHODS

RT-qPCR and western blot were conducted to determine the expression levels of C1QTNF6. RNA interference and overexpression of C1QTNF6 were constructed to identify the biological function of C1QTNF6 in cellular proliferative, migratory and invasive potentials in vitro. Dual-luciferase reporter assay was applied to identify the possible interaction between C1QTNF6 and miR-29a-3p. Moreover, RNA sequencing analysis of C1QTNF6 knockdown was performed to identify the potential regulatory pathways.

RESULTS

C1QTNF6 was upregulated in stage I LUAD tissues compared with adjacent non-cancerous tissues. Concurrently, C1QTNF6 knockdown could remarkably inhibit cell proliferation, migratory and invasive abilities, while overexpression of C1QTNF6 presented opposite results. Additionally, miR-29a-3p may serve as an upstream regulator of C1QTNF6 and reduce the expression of C1QTNF6. Subsequent experiments showed that miR-29a-3p could decrease the cell mobility and proliferation positive cell rates, as well as reduce the migratory and invasive possibilities in LUAD cells via downregulating C1QTNF6. Moreover, RNA sequencing analysis demonstrated that the cytokine-cytokine receptor interaction pathway may participate in the process of C1QTNF6 regulating tumor progression.

CONCLUSION

Our study first demonstrated that downregulation of C1QTNF6 could inhibit tumorigenesis and progression in LUAD cells negatively regulated by miR-29a-3p. These consequences could reinforce our awareness and understanding of the underlying mechanism and provide a promising therapeutic target for LUAD.

SFRP1 Negatively Modulates Pyroptosis of Fibroblast-Like Synoviocytes in Rheumatoid Arthritis: A Review

Secreted frizzled-related protein 1 (SFRP1) is a member of secretory glycoprotein SFRP family. As a primitive gene regulating cell growth, development and transformation, SFRP1 is widely expressed in human cells, including various cancer cells and fibroblast-like synoviocytes (FLS) of rheumatoid arthritis (RA). Deletion or silencing of SFRP1 involves epigenetic and other mechanisms, and participates in biological behaviors such as cell proliferation, migration and cell pyroptosis, which leads to disease progression and poor prognosis. In this review, we discuss the role of SFRP1 in the pathogenesis of RA-FLS and summarize different experimental platforms and recent research results. These are helpful for understanding the biological characteristics of SFRP1 in RA, especially the mechanism by which SFRP1 regulates RA-FLS pyroptosis through Wnt/β-catenin and Notch signaling pathways. In addition, the epigenetic regulation of SFRP1 in RA-FLS is emphasized, which may be considered as a promising biomarker and therapeutic target of RA.

The Role of Inflammasomes in Osteoarthritis and Secondary Joint Degeneration Diseases

Osteoarthritis is age-related and the most common form of arthritis. The main characteristics of the disease are progressive loss of cartilage and secondary synovial inflammation, which finally result in pain, joint stiffness, and functional disability. Similarly, joint degeneration is characteristic of systemic inflammatory diseases such as rheumatoid arthritis and gout, with the associated secondary type of osteoarthritis. Studies suggest that inflammation importantly contributes to the progression of the disease. Particularly, cytokines TNFα and IL-1β drive catabolic signaling in affected joints. IL-1β is a product of inflammasome activation. Inflammasomes are inflammatory multiprotein complexes that propagate inflammation in various autoimmune and autoinflammatory conditions through cell death and the release of inflammatory cytokines and damage-associated molecule patterns. In this article, we review genetic, marker, and animal studies that establish inflammasomes as important drivers of secondary arthritis and discuss the current evidence for inflammasome involvement in primary osteoarthritis. The NLRP3 inflammasome has a significant role in the development of secondary osteoarthritis, and several studies have provided evidence of its role in the development of primary osteoarthritis, while other inflammasomes cannot be excluded. Inflammasome-targeted therapeutic options might thus provide a promising strategy to tackle these debilitating diseases.

Transcranial Electromagnetic Treatment “Rebalances” Blood and Brain Cytokine Levels in Alzheimer’s Patients: A New Mechanism for Reversal of Their Cognitive Impairment

Background

The immune system plays a critical role in the development and progression of Alzheimer’s disease (AD). However, there is disagreement as to whether development/progression of AD involves an over-activation or an under-activation of the immune system. In either scenario, the immune system’s cytokine levels are abnormal in AD and in need of rebalancing. We have recently published a pilot clinical trial (https://clinicaltrials.gov/ct2/show/NCT02958930) showing that 2 months of daily in-home Transcranial Electromagnetic Treatment (TEMT) was completely safe and resulted in reversal of AD cognitive impairment.

Methods

For the eight mild/moderate AD subjects in this published work, the present study sought to determine if their TEMT administration had immunologic effects on blood or CSF levels of 12 cytokines. Subjects were given daily in-home TEMT for 2 months by their caregivers, utilizing first-in-class MemorEM™ devices.

Results

For eight plasma cytokines, AD subjects with lower baseline cytokine levels always showed increases in those cytokines after both a single treatment or after 2-months of daily TEMT. By contrast, those AD subjects with higher baseline cytokine levels in plasma showed treatment-induced decreases in plasma cytokines at both time points. Thus, a gravitation to reported normal plasma cytokine levels (i.e., a “rebalancing”) occurred with both acute and long-term TEMT. In the CSF, TEMT-induced a similar rebalancing for seven measurable cytokines, the direction and extent of changes in individual subjects also being linked to their baseline CSF levels.

Conclusion

Our results strongly suggest that daily TEMT to AD subjects for 2-months can “rebalance” levels for 11 of 12 cytokines in blood and/or brain, which is associated with reversal of their cognitive impairment. TEMT is likely to be providing these immunoregulatory effects by affecting cytokine secretion from: (1) blood cells traveling through the head’s vasculature, and (2) the brain’s microglia/astrocytes, choroid plexus, or neurons. This rebalancing of so many cytokines, and in both brain and systemic compartments, appears to be a remarkable new mechanism of TEMT action that may contribute substantially to it’s potential to prevent, stop, or reverse AD and other diseases of aging.

How Pyroptosis Contributes to Inflammation and Fibroblast-Macrophage Cross-Talk in Rheumatoid Arthritis

About thirty years ago, a new form of pro-inflammatory lytic cell death was observed and termed pyroptosis. Only in 2015, gasdermins were defined as molecules that create pores at the plasma membrane and drive pyroptosis. Today, we know that gasdermin-mediated death is an important antimicrobial defence mechanism in bacteria, yeast and mammals as it destroys the intracellular niche for pathogen replication. However, excessive and uncontrolled cell death also contributes to immunopathology in several chronic inflammatory diseases, including arthritis. In this review, we discuss recent findings where pyroptosis contributes to tissue damage and inflammation with a main focus on injury-induced and autoimmune arthritis. We also review novel functions and regulatory mechanisms of the pyroptotic executors gasdermins. Finally, we discuss possible models of how pyroptosis may contribute to the cross-talk between fibroblast and macrophages, and also how this cross-talk may regulate inflammation by modulating inflammasome activation and pyroptosis induction.

Saliva and Serum Cytokine Profiles During Oral Ulceration in Behçet's Disease

Behçet's disease (BD) is a chronic, multi-systemic disorder of unknown aetiology typified by recurrent oral and genital mucocutaneous lesions, uveitis and vasculitis. Innate and adaptive immune system dysregulation has been implicated in pathogenesis with alterations in serum cytokine profiles. Few studies have investigated salivary cytokines in BD, despite more than 90% of BD patients first presenting with oral ulceration. The aim of this pilot study was twofold; firstly to investigate whether cytokine levels in matched serum and saliva samples show a differential profile in BD (with and without oral ulcers), recurrent aphthous stomatitis (RAS) and healthy controls (HCs), and secondly, to explore if any differential profiles in serum and/or saliva could provide a panel of cytokines with diagnostic and therapeutic potential for BD. Concentrations of 12 cytokines (IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IFN-γ, TNF-α, TNF-β) were measured using the Human Th1/Th2 11-Plex FlowCytomix™ kit with IL-17A, in BD (N=20), RAS (N=6) and HCs (N=10). A differential range of cytokines was detected in serum and saliva with the majority of cytokine levels higher in saliva. The most prevalent salivary cytokines were IL-1β, IL-2, IL-8, IL-10 and TNF-α present in all samples in contrast to serum where the most prevalent cytokine detected was IL-8 (91.9%). The least abundant cytokine was IFN-γ in both saliva (43.2%) and serum (2.7%). After normalizing saliva for protein content, BD patients with oral ulcers (BD-MA) had significantly higher levels of salivary IL-1β (p=0.01), IL-8 (p=0.02), TNF-α (p=0.004) and IL-6 (p=0.01) than HCs. Notably, BD patients without oral ulcers (BD-MQ) also had significantly higher salivary IL-1β, IL-8 and TNF-α (p ≤ 0.05) than HCs. During relapsed (BD-RE) and quiet (BD-Q) systemic episodes, salivary IL-β and TNF-α were also significantly increased with IL-8 significantly higher only in BD-Q (p=0.02). BD oral ulcers signify a potential reactivation of systemic inflammation. Identifying cytokines released during asymptomatic episodes and oral ulceration might lead to targeted drug therapy to prevent recurrent oral ulcers and possible disease relapse. This is the first study to report salivary cytokine levels in BD. The detectable levels suggests cytokine profiling of BD saliva may provide an alternative, less invasive, sensitive procedure for frequent monitoring of disease activity and progression.

Synergistic Effects of Toll-Like Receptor 1/2 and Toll-Like Receptor 3 Signaling Triggering Interleukin 27 Gene Expression in Chikungunya Virus-Infected Macrophages

Chikungunya virus (CHIKV) is the etiological agent of chikungunya fever (CHIKF), a self-limiting disease characterized by myalgia and severe acute or chronic arthralgia. CHIKF is associated with immunopathology and high levels of pro-inflammatory factors. CHIKV is known to have a wide range of tropism in human cell types, including keratinocytes, fibroblasts, endothelial cells, monocytes, and macrophages. Previously, we reported that CHIKV-infected monocytes-derived macrophages (MDMs) express high levels of interleukin 27 (IL27), a heterodimeric cytokine consisting of IL27p28 and EBI3 subunits, that triggers JAK-STAT signaling and promotes pro-inflammatory and antiviral response, in interferon (IFN)-independent manner. Based on the transcriptomic analysis, we now report that induction of IL27-dependent pro-inflammatory and antiviral response in CHIKV-infected MDMs relies on two signaling pathways: an early signal dependent on recognition of CHIKV-PAMPs by TLR1/2-MyD88 to activate NF-κB-complex that induces the expression of EBI3 mRNA; and second signaling dependent on the recognition of intermediates of CHIKV replication (such as dsRNA) by TLR3-TRIF, to activate IRF1 and the induction of IL27p28 mRNA expression. Both signaling pathways were required to produce a functional IL27 protein involved in the induction of ISGs, including antiviral proteins, cytokines, CC- and CXC- chemokines in an IFN-independent manner in MDMs. Furthermore, we reported that activation of TLR4 by LPS, both in human MDMs and murine BMDM, results in the induction of both subunits of IL27 that trigger strong IL27-dependent pro-inflammatory and antiviral response independent of IFNs signaling. Our findings are a significant contribution to the understanding of molecular and cellular mechanisms of CHIKV infection.

Apoptosis, Autophagy, NETosis, Necroptosis, and Pyroptosis Mediated Programmed Cell Death as Targets for Innovative Therapy in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease that can lead to clinical manifestations of systemic diseases. Its leading features include chronic synovial inflammation and degeneration of the bones and joints. In the past decades, multiple susceptibilities for rheumatoid arthritis have been identified along with the development of a remarkable variety of drugs for its treatment; which include analgesics, glucocorticoids, nonsteroidal anti-inflammatory medications (NSAIDs), disease-modifying anti-rheumatic drugs (DMARDs), and biologic response modifiers (bDMARDs). Despite the existence of many clinical treatment options, the prognosis of some patients remains poor due to complex mechanism of the disease. Programmed cell death (PCD) has been extensively studied and ascertained to be one of the essential pathological mechanisms of RA. Its dysregulation in various associated cell types contributes to the development of RA. In this review, we summarize the role of apoptosis, cell death-associated neutrophil extracellular trap formation, necroptosis, pyroptosis, and autophagy in the pathophysiology of RA to provide a theoretical reference and insightful direction to the discovery and development of novel therapeutic targets for RA.

Pyroptosis-Mediated Periodontal Disease

Pyroptosis is a caspase-dependent process relevant to the understanding of beneficial host responses and medical conditions for which inflammation is central to the pathophysiology of the disease. Pyroptosis has been recently suggested as one of the pathways of exacerbated inflammation of periodontal tissues. Hence, this focused review aims to discuss pyroptosis as a pathological mechanism in the cause of periodontitis. The included articles presented similarities regarding methods, type of cells applied, and cell stimulation, as the outcomes also point to the same direction considering the cellular events. The collected data indicate that virulence factors present in the diseased periodontal tissues initiate the inflammasome route of tissue destruction with caspase activation, cleavage of gasdermin D, and secretion of interleukins IL-1β and IL-18. Consequently, removing periopathogens’ virulence factors that trigger pyroptosis is a potential strategy to combat periodontal disease and regain tissue homeostasis.

A Serum Biomarker Panel of exomiR-451a, exomiR-25-3p and Soluble TWEAK for Early Diagnosis of Rheumatoid Arthritis

Background

The etiology of rheumatoid arthritis (RA) remains poorly understood. Early and accurate diagnosis still difficult to achieve. Inflammatory related molecules released into the circulation such cytokines and exosome-derived microRNAs (exomiRNAs) could be good candidates for early diagnosis of autoimmune diseases. We sought to discover a serum biomarker panel for the early detection of RA based on exomiRNAs and inflammatory markers.

Methods

A 179 miRNAs-microarray panel was analyzed in a pilot study (4 early RA and 4 controls). Validation of deregulated exomiRNAs was performed in a larger cohort (24 patients with early RA and 24 controls). miRNet software was used to predict exomiRNA gene-targets interactions. Potentially altered pathways were analyzed by Reactome pathway database search. STRING database was used to predict protein-protein interaction networks. Enzyme-linked immunosorbent assay was used to measure serum levels of sTWEAK and sCD163. Signature biomarker candidates were statistical analyzed.

Results

We detected 11 differentially expressed exomiRNAs in early RA pilot study. Validation analysis revealed that 6/11 exomiRNAs showed strong agreement with the pilot microarray data (exomiR-144-3p, -25-3p, -15a-5p, -451a, -107 and -185-5p). sTWEAK and sCD163 biomarkers were significantly elevated in the serum of patients with early RA. Receiver operating characteristic (ROC) analysis showed that the best panel to diagnose early RA contained exomiR-451a, exomiR-25-3p and sTWEAK, and could correctly classify 95.6% of patients, with an area under the ROC curve of 0.983 and with 100% specificity and 85.7% sensitivity. The YWHAB gene was identified as a common target of the putative miRNA-regulated pathways.

Conclusion

A novel serum biomarker panel composed of exomiR-451a, exomiR-25-3p and serum levels of sTWEAK may have use in the early clinical diagnosis of RA. A new predicted exomiRNA-target gene YHWAB has been identified and may have a relevant role in the development of RA.

Association between inflammatory cytokines and immune-checkpoint molecule in rheumatoid arthritis

Background

Anti-citrullinated peptide antibodies (ACPA) and inflammatory cytokines play important roles in the development of rheumatoid arthritis (RA). T cell immunoglobulin and mucin–domain containing–3 (TIM–3) is an immune-checkpoint molecule involved in inhibitory signaling. Galectin–9 (Gal–9) mediated ligation of TIM–3 induces the amelioration of autoimmune diseases. TIM–3 is expressed in synovial osteoclasts and involved in the rheumatoid bone destruction. The aim of this study was to investigate the relationships between inflammatory cytokines and immune–checkpoint molecules in RA patients.

Methods

Serum levels of interleukin–6 (IL–6), tumor necrosis factor–α (TNF–α), soluble TIM–3 (sTIM–3) and Gal–9 were determined by ELISA. Patients were stratified into two groups based on ACPA titers: low-medium ACPA (ACPA <200 U/mL) and high ACPA (ACPA ≥200 U/mL). Serum levels of cytokines or immune-checkpoint molecules were evaluated between RA patients with low-medium ACPA titers and high ACPA titers.

Results

Elevated serum levels of inflammatory cytokines were correlated with DAS28–ESR in RA patients. Although serum levels of sTIM–3 were elevated in RA patients, significant correlations between sTIM–3 and cytokines (IL–6 or TNF–α) were observed exclusively in RA patients with low-medium ACPA titers (<200 U/mL). Serum levels of IL–6 and TNF–α levels were significantly correlated with elevated Gal–9 levels regardless of ACPA status. A significant correlation between IL–6 and Gal–9 was observed in RA patients without advanced joint damage. Conversely, a significant correlation between TNF–α and Gal–9 was observed in RA patients with advanced joint damage.

Conclusions

Our data indicated that there are positive correlations between circulating inflammatory cytokines and checkpoint molecules in RA patients and these interactions can be modulated by ACPA status or joint damage stage.

Synovial fluid niche promoted differentiation of dental follicle mesenchymal stem cells toward chondrogenesis in rheumatoid arthritis

Objectives

In this study, we aimed to investigate the differentiation potential of dental follicle mesenchymal stem cells (MSCs) in the synovial fluid (SF) niche of early-onset or end-stage rheumatoid arthritis (RA).

Patients and methods

Between May 2020 and January 2021, six patients (1 male, 5 females; mean age: 57.5±11.2 years; range, 49 to 65 years) who were diagnosed with RA with the indication of SF aspiration were included in the study. The third passage dental follicle stem cells (DFSCs) were cocultured with fresh SF samples of end-stage or early-onset RA patients in micromass culture system for 21 days. SF samples were analyzed for secreted cytokines. Chondrogenic markers (CD49e, CD49f) were analyzed in DFSCs, gene expression analysis was performed for the expressions of Col I, Col II, Aggrecan and Sox-9, and histochemical analysis was performed by staining three-dimensional pellets with anti-collagen II antibody. The neutralization assay was performed with anti-interleukin (IL)-6, anti-interferon-gamma (IFN-g), and anti-IL-1beta(b).

Results

The high levels of IL-1b and IL-6 were observed in end-stage RA patients’ SF samples compared to the early-onset patients (p<0.05). The CD49e and CD49f expressions in DFSCs were significantly higher in the SF samples of end-stage RA patients (p<0.05). Also, the Col II, Sox-9 and Aggrecan messenger ribonucleic acid (mRNA) expressions increased in the DFSCs, when cultured with end-stage RA patients’ SF samples (p<0.01). Collagen-II expression in histochemical analysis of micromass pellets was higher in the DFSCs cultured with end-stage RA patients’ SF samples. The neutralization of IL-6 significantly decreased the CD49e and CD49f expressions (p<0.05).

Conclusion

The high levels of IL-6 in SF niche of end-stage RA patients were found to differentiate DFSCs toward chondrogenesis. Based on these findings, DFSCs can be used as a new cell-based treatment in RA patients for the cartilage damage.

The role of the cholinergic anti-inflammatory pathway in autoimmune rheumatic diseases

The cholinergic anti-inflammatory pathway (CAP) is a classic neuroimmune pathway, consisting of the vagus nerve, acetylcholine (ACh)-the pivotal neurotransmitter of the vagus nerve-and its receptors. This pathway can activate and regulate the activities of immune cells, inhibit cell proliferation and differentiation, as well as suppress cytokine release, thereby playing an anti-inflammatory role, and widely involved in the occurrence and development of various diseases; recent studies have demonstrated that the CAP may be a new target for the treatment of autoimmune rheumatic diseases. In this review, we will summarize the latest progress with the view of figuring out the role of the cholinergic pathway and how it interacts with inflammatory reactions in several autoimmune rheumatic diseases, and many advances are results from a wide range of experiments performed in vitro and in vivo.

Structural equation modelling provides insights to understand the construct of chronic pain in women with rheumatoid arthritis

OBJECTIVES

We aimed to adopt a multidimensional approach and investigate the interconnections between biomarkers (cytokines, matrix metalloproteinases, and cortisol) and psychosocial aspects considering pain acceptance, the individual construct of pain perception in terms of blood inflammation biomarkers, anxiety, self-efficacy, and functional performance and to define the quality of life (QoL) in women with rheumatoid arthritis (RA).

METHODS

An observational cross-sectional study with a total of 42-RA participants, with chronic pain and 42-women without rheumatic diseases or chronic pain were included. A structural equation model was used to investigate the association between independent variables.

RESULTS

Women with RA presented high blood biomarker levels, representing an intense inflammatory process. The participants with RA reported moderate pain most of the time, a worsening QoL, functionality, engagement in activities, and a willingness to live with pain and self-efficacy. It was found that the higher the chronic pain, the greater the intensity of pain perceived by these women with RA, as well as, the worse the functionality, the higher the perceived pain.

CONCLUSIONS

The exacerbation of pain perception leads to worsening of the experience of chronic pain. The new construct of pain experience should include functionality as a crucial factor in understanding the mechanisms underlying pain.

Metabolomics profiling predicts outcome of tocilizumab in rheumatoid arthritis: an exploratory study

INTRODUCTION

To study metabolic signatures can be used to identify predictive biomarkers for a patient's therapeutic response.

OBJECTIVES

We hypothesized that the characterization of a patients' metabolic profile, utilizing one-dimensional nuclear magnetic resonance (¹H-NMR), may predict a response to tocilizumab in patients with rheumatoid arthritis (RA).

METHODS

40 active RA patients meeting the 2010 ACR/EULAR classification criteria initiating treatment with tocilizumab were recruited. Clinical outcomes were determined at baseline, and after six and twelve months of treatment. EULAR response criteria at 6 and 12 months to categorize patients as responders and non-responders. Blood was collected at baseline and after six months of tocilizumab therapy. ¹H-NMR was used to acquire a spectra of plasma samples. Chenomx NMR suite 8.5 was used for metabolite identification and quantification. SPSS v.27 and MetaboAnalyst 4.0 were used for statistical and pathway analysis.

RESULTS

Isobutyrate, 3-hydroxybutyrate, lysine, phenylalanine, sn-glycero-3-phosphocholine, tryptophan and tyrosine were significantly elevated in responders at the baseline. OPLS-DA at baseline partially discriminated between RA responders and non-responders. A multivariate diagnostic model showed that concentrations of 3-hydroxybutyrate and phenylalanine improved the ability to specifically predict responders classifying 77.1% of the patients correctly. At 6 months, levels of methylamine, sn-glycero-3-phosphocholine and tryptophan tended to still be low in non-responders.

CONCLUSION

The relationship between plasma metabolic profiles and the clinical response to tocilizumab suggests that ¹H-NMR may be a promising tool for RA therapy optimization. More studies are needed to determine if metabolic profiling can predict the response to biological therapies in RA patients.

Interferon-related gene expression in response to TNF inhibitor treatment in ankylosing spondylitis patients: a pilot study

OBJECTIVE

Ankylosing spondylitis (AS) is a chronic inflammatory arthritis primarily affecting the spine and sacroiliac joints. TNF inhibitor (TNFi) drugs are recommended for patients not responding to NSAIDs; however, there is a significant need for biomarkers of response. IFN-regulated genes (IRGs) and other cytokines/chemokines are linked to autoimmune diseases and have been associated with treatment response. Our objective was to explore whether IRGs and cytokines/chemokines can be associated with response to TNFiagents in AS.

METHODS

Peripheral blood mononuclear cells were obtained from 26 AS patients who were to receive a TNFi (I, n = 15) or placebo (P, n = 11) at week 0 and week 22. Response (R)/non-response (NR) was defined as reduction in ASDAS ≥ 1.2 points or reduction in sacroiliac/vertebral MRI lesions. The expression of 96 genes was quantified using TaqMan assays. Finally, ELISA was used to measure IL-6 in serum samples from another 38 AS patients.

RESULTS

Analysis of gene expression in 26 baseline samples segregated patients into four groups defined by a signature of 15 genes (mainly IRGs). ASDAS response was associated with one group independently of treatment received. We then analysed response to the TNFi (n = 15) and identified a 12-gene signature associated with MRI response. A third IRG signature was also associated with a reduction in IRGs expression post-TNFi samples (n = 10 pairs). Finally, decreased circulating IL-6 was associated with BASDAI-R.

CONCLUSION

This pilot study suggests an association between IRG expression and response to TNFi in AS. These findings require validation in a larger cohort in order to construct predictive algorithms for patient stratification.

Cytokines: From Clinical Significance to Quantification

Cytokines are critical mediators that oversee and regulate immune and inflammatory responses via complex networks and serve as biomarkers for many diseases. Quantification of cytokines has significant value in both clinical medicine and biology as the levels provide insights into physiological and pathological processes and can be used to aid diagnosis and treatment. Cytokines and their clinical significance are introduced from the perspective of their pro- and anti-inflammatory effects. Factors affecting cytokines quantification in biological fluids, native levels in different body fluids, sample processing and storage conditions, sensitivity to freeze-thaw, and soluble cytokine receptors are discussed. In addition, recent advances in in vitro and in vivo assays, biosensors based on different signal outputs and intracellular to extracellular protein expression are summarized. Various quantification platforms for high-sensitivity and reliable measurement of cytokines in different scenarios are discussed, and commercially available cytokine assays are compared. A discussion of challenges in the development and advancement of technologies for cytokine quantification that aim to achieve real-time multiplex cytokine analysis for point-of-care situations applicable for both biomedical research and clinical practice are discussed.

Antirheumatic treatment is associated with reduced serum Syndecan-1 in Rheumatoid Arthritis

The endothelial glycocalyx (EG) is essential for proper function of the endothelium and for vascular integrity, but its role in premature atherogenesis in rheumatoid arthritis (RA) has not been studied yet. EG impairment can play a role in pathogenesis of vascular disease, and one of its characteristics is shedding of syndecan-1 from endothelial cells. Syndecan-1 shedding is mediated by matrix metalloproteinase-9 (MMP-9) and counteracted by tissue inhibitor of metalloproteinases (TIMP)-1. Cardiovascular disease risk in RA is reversible by disease modifying antirheumatic drugs (DMARDs), but the exact modes of action are still unclear. Therefore, we examined effects of DMARDs on syndecan-1, MMP-9 and TIMP-1 in RA patients, and searched for associations between these parameters and inflammatory activity. From the observational PSARA study, we examined 39 patients starting with methotrexate (MTX) monotherapy (in MTX naïve patients, n = 19) or tumor necrosis factor inhibitors (TNFi) in combination with MTX (in MTX non-responders, n = 20) due to active RA. Serum syndecan-1, MMP-9 and TIMP-1 were measured at baseline and after six weeks of treatment. Serum syndecan-1 (p = 0.008) and TIMP-1 (p<0.001) levels decreased after six weeks of anti-rheumatic treatment. Levels of MMP-9 also decreased, but the difference was not statistically significant. The improvement in syndecan-1 levels were independent of changes in inflammatory activity. There was no significant difference in changes in syndecan-1 levels from baseline to 6 weeks between the MTX and TNFi groups, however the change was significant within the MTX group. Six weeks of antirheumatic treatment was associated with reduction in serum levels of syndecan-1, which might reflect reduced syndecan-1 shedding from EG. Thus, it is possible that EG-preserving properties of DMARDs might contribute to their cardioprotective effects. These effects may be at least partly independent of their anti-inflammatory actions. Our findings do not support the notion that syndecan-1 shedding in RA is mediated mainly by increased MMP-9 or decreased TIMP-9 serum concentration.

Serum IL-35 is decreased in overweight patients with rheumatoid arthritis: its correlation with Th1/Th2/Th17-related cytokines

Background

Obesity is correlated with worse drug responses and high disease activity in patients with rheumatoid arthritis (RA). Interleukin (IL)-35 is a novel anti-inflammatory cytokine that mainly produced by regulatory T (Treg). This study was performed to analyze whether IL-35 was correlated with obesity in RA and investigate the correlation between other Th1/Th2/Th17-related cytokines and obesity in RA.

Results

The serum IL-35 level was analyzed in RA (n = 81) and healthy donors (n = 53) by ELISA assay, and was compared between three groups (body mass index (BMI) < 18.5,≥18.5 to 25, > 25). Serum cytokines including IL-2, IL-4, IL-10, IL-17, INF-γ, TNF-α levels were measured using Flowcytometry assay. Clinical information was extracted from medical records. Serum IL-35 level in overweight patients were significantly decreased than those in lean patients. Furthermore, Th1/Th2/Th17-related cytokines from overweight patients with RA showed the characteristic immunological features. Serum IL-6, IL-17 and TNF-α levels were positively correlated with BMI. However, serum IL-2, IL-4, IL-10 and IFN-γ concentrations were not correlated with BMI.

Conclusions

Quantitative changes in serum IL-35 level were characteristic in overweight patients with RA. These findings indicate that IL-35 plays an important role in the development of RA and may prove to be a potential biomarker of active RA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12865-021-00431-x.

Cholinergic anti-inflammatory pathway and connective tissue diseases

Connective tissue diseases (CTDs) consist of an extensive range of heterogeneous medical conditions, which are caused by immune-mediated chronic inflammation and influences the various connective tissues of the body. They include rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, vasculitis, Sjögren's syndrome, Behcet's disease, and many other autoimmune CTDs. To date, several anti-inflammatory approaches have been developed to reduce the severity of inflammation or its subsequent organ manifestations. As a logical mechanism to harnesses the undesired inflammation, some studies investigated the role of the intrinsic cholinergic anti-inflammatory pathway (CAP) in the modulation of chronic inflammation. Many different experimental and clinical models have been developed to evaluate the therapeutic significance of the CAP in CTDs. On the other hand, an issue that is less emphasized in this regard is the presence of autonomic neuropathy in CTDs, which influences the efficiency of CAP in such clinical settings. This condition occurs during CTDs and is a well-known complication of patients suffering from them. The advantages and limitations of CAP in the control of inflammatory responses and its possible therapeutic benefits in the treatment of CTDs are the main subjects of the current study. Therefore, this narrative review article is provided based on the recent findings of the complicated role of CAP in CTDs which were retrieved by searching Science Direct, PubMed, Google Scholar, and Web of Science. It seems that delineating the complex influences of CAP would be of great interest in designing novel surgical or pharmacological therapeutic strategies for CTDs therapy.

Recent advances in gold nanoparticle-based lateral flow immunoassay for the detection of bacterial infection

Diagnosis of bacterial infections (BI) is becoming an increasingly difficult task in clinical practice due to their high prevalence and frequency, as well as the growth of antibiotic resistance worldwide. World Health Organization (WHO) reported antibiotic resistance is a major public health problem. BI becomes difficult or impossible to treat when the bacteria acquire immunity against antibiotics. Thus, there is a need for a quick and accurate technique to detect infection. Lateral flow immunoassay (LFIA) is an ideal technique for point-of-care testing of a disease or pathological changes inside the human body. In recent years, several LFIA based strips are being used for the detection of BI by targeting specific analytes which may range from the causative bacterium, whole-cell, DNA, or biomarker. Numerous nanoparticles like lipid-based nanoparticles, polymeric nanoparticles, and inorganic nanoparticles such as quantum dots, magnetic, ceramic, and metallic nanoparticles (copper, silver gold, iron) are widely being used in the advanced treatment of BI. Out of these gold nanoparticle (AuNPs), is being used for detection BI more effectively than other nanoparticles due to their surface functionalization, extraordinary chemical stability, biorecognition, and signal amplification properties and help to improve in conjugation with capture antibodies, and act as a color marker with unique optical properties on LFIA strips. Herein, a review that provides an overview of the principle of LFIA, how LFIA based strip is developed, and how it is helpful to detect a specific biomarker for bedside detection of the BI.

Serological Biomarkers and Indices for the Current Activity and Prognosis of ANCA-Associated Vasculitis: Experience in a Single Centre in Korea

Small vessel vasculitis is composed of two types of vasculitis based on immune-complex deposits, immune-complex vasculitis and antineutrophil cytoplasmic antibody-associated vasculitis (AAV) according to the 2012 Chapel Hill Consensus Conferences Nomenclature of Vasculitis. In general, the current disease-states are assessed in three ways in real clinical practice such as activity, damage and functional status. Birmingham vasculitis activity score (BVAS, version 3) and five-factor score were calculated for assessing the cross-sectional activity and for predicting the prognosis of AAV, respectively. Since BVAS includes a wide spectrum of nine systemic items with differently weighted scores based on new-onset/worsening or persistent each symptom, it has been considered as the most reliable tool to assess AAV activity to date. However, since BVAS represents both cross-sectional and chronic clinical features, it has a limitation in flexibly reflecting the cross-sectional activity or severity of AAV. In addition, the heterogeneous items of BVAS are difficult to reflect the close correlation between BVAS and AAV pathogenesis. It is practically difficult to discover new biomarkers or indices that exceed the reliability of AAV-specific indices or acute-phase reactants established by long clinical experience. However, efforts to discover and develop new biomarkers or indices are expected to complement the clinical unmet need of existing AAV-specific indices and acute-phase reactants. In this review, we reviewed the serological biomarkers and indices that have been reported to date and introduced studies that investigated serological biomarkers and indices in Korean patients with AAV.

[Rheumatoid arthritis of the hand : Part 1: Clinical aspects]

BACKGROUND

All rheumatic autoimmune diseases are associated with arthritis of the hands, whereby it is possible to differentiate between typical and atypical arthritis patterns, which are key for diagnosis. Rheumatoid arthritis is commonly associated with synovitis of the hands. While patients with disease duration of less than 2 years were previously considered to have early disease, unfavorable prognosis with delayed initiation of therapy has reduced this time frame to 3 months after symptom onset.

OBJECTIVE

The aim is to provide radiologists with a systematic description of the clinical aspects of rheumatoid arthritis in order to better understand this entity so that they can confidently recognize arthritis patterns in the hands at an early stage.

MATERIALS AND METHODS

Narrative review based on the current literature on the subject from radiological and rheumatological point of view.

RESULTS

Synovitis of the hands is a common manifestation in rheumatoid arthritis. Knowledge of the epidemiology, prevalence, incidence, pathogenesis, genetics, etiology, biology and immunology, serology, histology, clinical presentation, the classification and diagnostic criteria, and therapy is essential for the radiologist to better understand the image-based morphologic changes associated with this complex disease and thereby gain greater confidence in the diagnosis of early stages.

CONCLUSIONS

For the diagnosis of rheumatoid arthritis, the radiologist must be familiar with basic clinical knowledge to confidently analyze the patterns present in arthritis of the hands at initial diagnosis and during the course of the disease, which are essential for therapy decisions.

Plasma interleukin-21 levels and genetic variants are associated with susceptibility to rheumatoid arthritis

Background

Rheumatoid Arthritis (RA) is a chronic inflammatory condition characterized by autoantibodies development and an elevated spectrum of pro-inflammatory cytokines. Previous reports highlighted a relationship between IL-21and the pathogenesis of RA. Although elevated IL-21 levels have been reported in RA patients, the association of common IL-21 genetic variants with a predisposition to RA development in the Chinese population lacks.

Materials and methods

Five hundred and fourteen Chinese subjects (healthy controls: 303 and rheumatoid arthritis patients: 211) were enrolled in the study. Clinical data of patients were collected from medical records, and patients were treated as per the guidelines. Common single nucleotide polymorphisms in the IL-21 gene (rs907715, rs2221903, rs2055979 and rs6822844) were genotyped by TaqMan SNPs genotyping method. IL-21 level in plasma of RA patients and healthy subjects was measured by ELISA.

Results

The plasma level of IL-21 was significantly higher in subjects with rheumatoid arthritis relative to healthy controls (p < 0.0001). A positive correlation was observed between IL-21 level and DAS28 score, indicating the association of the cytokine with the worsening of the disease (Spearman r = 0.61, p < 0.0001). The prevalence of AA genotype (rs2055979) was significantly higher in RA subjects than in the controls (p < 0.0001, χ2 = 34.73, OR = 4.34, 95% CI = 2.623 to 7.219). Furthermore, elevated plasma IL-21 was observed in the rs2055979-AA genotype compared to CC type (p < 0.0001).

Conclusion

IL-21 plays a crucial function in rheumatoid arthritis pathogenesis. IL-21 rs2055979 polymorphism is associated with IL-21 plasma levels and is predisposed to RA development in the Chinese population.