TNF inhibitor therapy for rheumatoid arthritis

Inflammation-induced left ventricular fibrosis is partially mediated by tumor necrosis factor-α

OBJECTIVE

To determine the mechanisms of inflammation-induced left ventricular (LV) remodeling and effects of blocking circulating tumor necrosis factor alpha (TNF-α) in a model of systemic inflammation.

METHODS

Seventy Sprague-Dawley rats were divided into three groups: the control group, the collagen-induced arthritis (CIA) group, and the anti-TNF-α group. Inflammation was induced in the CIA and anti-TNF-α groups. Following the onset of arthritis, the anti-TNF-α group received the TNF-α inhibitor, etanercept, for 6 weeks. LV geometry and function were assessed with echocardiography. Circulating inflammatory markers were measured by ELISA and LV gene expression was assessed by comparative TaqMan® polymerase chain reaction.

RESULTS

The LV relative gene expression of pro-fibrotic genes, transforming growth factor β (TGFβ) (p = 0.03), collagen I (Col1) (p < 0.0001), and lysyl oxidase (LOX) (p = 0.002), was increased in the CIA group compared with controls, consistent with increased relative wall thickness (p = 0.0009). Col1 and LOX expression in the anti-TNF-α group were similar to controls (both, p > 0.05) and tended to be lower compared to the CIA group (p = 0.06 and p = 0.08, respectively), and may, in part, contribute to the decreased relative wall thickness in the anti-TNF-α group compared to the CIA group (p = 0.03). In the CIA group, the relative gene expression of matrix metalloproteinase 2 (MMP2) and MMP9 was increased compared to control (p = 0.04) and anti-TNF-α (p < 0.0001) groups, respectively.

CONCLUSION

Chronic systemic inflammation induces fibrosis and dysregulated LV extracellular matrix remodeling by increasing local cardiac pro-fibrotic gene expression, which is partially mediated by TNF-α. Inflammation-induced LV diastolic dysfunction is likely independent of myocardial fibrosis.

Mesenchymal Stem Cell-Based Therapy for Rheumatoid Arthritis

Mesenchymal stem cells (MSCs) have great potential to differentiate into various types of cells, including but not limited to, adipocytes, chondrocytes and osteoblasts. In addition to their progenitor characteristics, MSCs hold unique immunomodulatory properties that provide new opportunities in the treatment of autoimmune diseases, and can serve as a promising tool in stem cell-based therapy. Rheumatoid arthritis (RA) is a chronic systemic autoimmune disorder that deteriorates quality and function of the synovium membrane, resulting in chronic inflammation, pain and progressive cartilage and bone destruction. The mechanism of RA pathogenesis is associated with dysregulation of innate and adaptive immunity. Current conventional treatments by steroid drugs, antirheumatic drugs and biological agents are being applied in clinical practice. However, long-term use of these drugs causes side effects, and some RA patients may acquire resistance to these drugs. In this regard, recently investigated MSC-based therapy is considered as a promising approach in RA treatment. In this study, we review conventional and modern treatment approaches, such as MSC-based therapy through the understanding of the link between MSCs and the innate and adaptive immune systems. Moreover, we discuss recent achievements in preclinical and clinical studies as well as various strategies for the enhancement of MSC immunoregulatory properties.

Cardiovascular Risk Associated With TNF Alpha Inhibitor Use in Patients With Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by inflammation and pannus formation, with subsequent joint and cartilage degradation. Treatment commonly targets inflammatory cytokines, including tumor necrosis factor (TNF) alpha, which is a potent inflammatory cytokine required for cell signaling, regulation, and apoptosis, as well as for other cellular functions including immune response. TNF alpha inhibitors have demonstrated benefits in improving RA patient outcomes in terms of immune function and symptomatology. While TNF alpha inhibitors are generally beneficial, some studies have demonstrated that TNF alpha inhibitors may increase the risk of adverse cardiovascular events. While this continues to be debated, our study investigates the role of Tumor Necrosis Factor Receptor 1 (TNFR1) and Tumor Necrosis Factor Receptor 2 (TNFR2) in cardiac tissue. TNFR1 is an apoptotic receptor and its inhibition by TNF alpha inhibitors is subsequently cardioprotective. However, TNF alpha inhibitors may be inhibiting TNFR2 receptors even more so than TNFR1 receptors. TNFR2 is primarily a cardioprotective receptor and its greater inhibition results in the cardiovascular morbidity associated with TNF alpha inhibitors.

Modulation of inflammation by anti-TNF α mAb-dendrimer nanoparticles loaded in tyramine-modified gellan gum hydrogels in a cartilage-on-a-chip model

Rheumatoid arthritis (RA) is an autoimmune and chronic inflammatory disease characterized by joint inflammation. Since the inflammatory condition plays an important role in the disease process, it is important to develop and test new therapeutic approaches that specifically target and treat joint inflammation. In this study, a human 3D inflammatory cartilage-on-a-chip model was established to test the therapeutic efficacy of anti-TNFα mAb-CS/PAMAM dendrimer NPs loaded-Tyramine-Gellan Gum in the treatment of inflammation. The results showed that the proposed therapeutic approach applied to the human monocyte cell line (THP-1) and human chondrogenic primary cells (hCH) cell-based inflammation system revealed an anti-inflammatory capacity that increased over 14 days. It was also possible to observe that Coll type II was highly expressed by inflamed hCH upon the culture with anti-TNF α mAb-CS/PAMAM dendrimer NPs, indicating that the hCH cells were able maintain their biological function. The developed preclinical model allowed us to provide more robust data on the potential therapeutic effect of anti-TNF α mAb-CS/PAMAM dendrimer NPs loaded-Ty-GG hydrogel in a physiologically relevant model.

Anti-inflammatory activities of a new VEGF blocker, Conbercept

BACKGROUND

Angiogenesis and inflammation exhibit a mutually reinforcing relationship in many human diseases. Vascular endothelial growth factor (VEGF) is one of the most important proangiogenic mediators. Conbercept is a novel VEGF inhibitor.

METHOD

Type II collagen-induced rat rheumatoid arthritis (CIA) model was established to evaluate the anti-chronic inflammation activities of Conbercept. ELISA was used to measure the concentrations of immune factors in the blood of arthritis rats. The xylene-induced ear edema was conducted to evaluate the effect of Conbercept on acute inflammation.

RESULT AND DISCUSSION

Our results showed that Conbercept significantly reduced the paw edema volume and the arthritis index in CIA rats. Furthermore, we found that Conbercept decreased the serum levels of vascular endothelial growth factor (VEGF), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in CIA rats. Xylene-induced ear edema is a widely used method to study acute inflammation. Conbercept significantly inhibited xylene-induced ear edema.

CONCLUSION

All results indicate that Conbercept exhibits significant inhibition of acute and chronic inflammation.

Tumor necrosis factor-α expression aberration of M1/M2 macrophages in adult high-functioning autism spectrum disorder

The etiology of autism spectrum disorder (ASD) is complex, and its pathobiology is characterized by enhanced inflammatory activities; however, the precise pathobiology and underlying causes of ASD remain unclear. This study was performed to identify inflammatory indicators useful for diagnosing ASD. The mRNA expression of cytokines, including tumor necrosis factor-α (TNF-α), was measured in cultured M1 and M2 macrophages from patients with ASD (n = 29) and typically developed (TD) individuals (n = 30). Additionally, TNF-α expression in the monocytes of patients with ASD (n = 7), showing aberrations in TNF-α expression in M1/M2 macrophages and TD individuals (n = 6), was measured. TNF-α expression in M1 macrophages and the TNF-α expression ratio in M1/M2 macrophages were markedly higher in patients with ASD than in TD individuals; however, this increase was not observed in M2 macrophages (M1: sensitivity = 34.5%, specificity = 96.7%, area under the curve = 0.74, positive likelihood ratio = 10.34; ratio of M1/M2: sensitivity = 55.2%, specificity = 96.7%, area under the curve = 0.79, positive likelihood ratio = 16.55). Additionally, TNF-α expression in monocytes did not significantly differ between patients with ASD and TD individuals. In conclusion, further studies on TNF-α expression in cultured macrophages may improve the understanding of ASD pathobiology. LAY SUMMARY: TNF-α expression in differentiated M1 macrophages and TNF-α expression ratio in differentiated M1/M2 macrophages were markedly higher in patients with ASD than in TD individuals, while no difference in TNF-α expression was found in pre-differentiation cells such as monocytes. These measurements allow elucidation of the novel pathobiology of ASD and can contribute to biomarker implementation for the diagnosis of adult high-functioning ASD.

A plug-and-play platform of ratiometric bioluminescent sensors for homogeneous immunoassays

Heterogeneous immunoassays such as ELISA have become indispensable in modern bioanalysis, yet translation into point-of-care assays is hindered by their dependence on external calibration and multiple washing and incubation steps. Here, we introduce RAPPID (Ratiometric Plug-and-Play Immunodiagnostics), a mix-and-measure homogeneous immunoassay platform that combines highly specific antibody-based detection with a ratiometric bioluminescent readout. The concept entails analyte-induced complementation of split NanoLuc luciferase fragments, photoconjugated to an antibody sandwich pair via protein G adapters. Introduction of a calibrator luciferase provides a robust ratiometric signal that allows direct in-sample calibration and quantitative measurements in complex media such as blood plasma. We developed RAPPID sensors that allow low-picomolar detection of several protein biomarkers, anti-drug antibodies, therapeutic antibodies, and both SARS-CoV-2 spike protein and anti-SARS-CoV-2 antibodies. With its easy-to-implement standardized workflow, RAPPID provides an attractive, fast, and low-cost alternative to traditional immunoassays, in an academic setting, in clinical laboratories, and for point-of-care applications.

Many current immunoassays require multiple washing, incubation and optimization steps. Here the authors present Ratiometric Plug-and-Play Immunodiagnostics (RAPPID), a generic assay platform that uses ratiometric bioluminescent detection to allow sandwich immunoassays to be performed directly in solution.

Oligonucleotide Therapies in the Treatment of Arthritis: A Narrative Review

Osteoarthritis (OA) and rheumatoid arthritis (RA) are two of the most common chronic inflammatory joint diseases, for which there remains a great clinical need to develop safer and more efficacious pharmacological treatments. The pathology of both OA and RA involves multiple tissues within the joint, including the synovial joint lining and the bone, as well as the articular cartilage in OA. In this review, we discuss the potential for the development of oligonucleotide therapies for these disorders by examining the evidence that oligonucleotides can modulate the key cellular pathways that drive the pathology of the inflammatory diseased joint pathology, as well as evidence in preclinical in vivo models that oligonucleotides can modify disease progression.

The Outcome of Stem Cell-Based Therapies on the Immune Responses in Rheumatoid Arthritis

Rheumatoid arthritis as a common autoimmune inflammatory disorder with unknown etiology can affect 0.5-1% of adults in developed countries. It involves more than just the patient's joints and can be accompanied by several comorbidities and affect cardiovascular, pulmonary, and some other systems of the human body. Although cytokine-mediated pathways are mentioned to have a central role in RA pathogenesis, adaptive and innate immune systems and intracellular signaling pathways all have important roles in this process. Non-steroidal anti-inflammatory drugs, glucocorticoids, conventional disease-modifying anti-rheumatic drugs, and biological agents are some mentioned medications used for RA. They are accompanied by some adverse effects and treatment failures which elucidates the needing for novel and more powerful therapeutic approaches. Stem cell-based therapies and their beneficial effects on therapeutic processes of different diseases have been founded so far. They can be an alternative and promising therapeutic approach for RA, too; due to their effects on immune responses of the disease. This review, besides some explanations about RA characteristics, addresses the outcome of the stem cell-based therapies including mesenchymal stem cell transplantation and hematopoietic stem cell transplantation for RA and explains their effects on the disease improvement.

IL-17C in human mucosal immunity: More than just a middle child

Interleukin-17C (IL-17C) is an understudied member of the IL-17 family of cytokines. Its synthesis is induced by both cytokines and pathogenic stimuli in a variety of cell types, most often expressed at mucosal and barrier surfaces. IL-17C expression is dysregulated in a variety of autoinflammatory and autoimmune diseases including inflammatory bowel disease, psoriasis, and atopic dermatitis, yet it is protective against bacterial infections of the gut, skin, and lungs. In this review we highlight studies on IL-17C regulation and its function at human mucosal surfaces. Understanding the relationship between IL-17C and autoinflammatory and autoimmune diseases of the mucosa and defining the beneficial and pathogenic functions of the cytokine in inflammatory responses are the first steps in determining the potential for IL-17C as a therapeutic target.

Topical nanocarriers for management of Rheumatoid Arthritis: A review

Rheumatoid arthritis (RA) is a systemic autoimmune disease manifested by chronic joint inflammation leading to severe disability and premature mortality. With a global prevalence of about 0.3%-1% RA is 3-5 times more prevalent in women than in men. There is no known cure for RA; the ultimate goal for treatment of RA is to provide symptomatic relief. The treatment regimen for RA involves frequent drug administration and high doses of NSAIDs such as indomethacin, diclofenac, ibuprofen, celecoxib, etorcoxib. These potent drugs often have off target effects which drastically decreases patient compliance. Moreover, conventional non-steroidal anti-inflammatory have many formulation challenges like low solubility and permeability, poor bioavailability, degradation by gastrointestinal enzymes, food interactions and toxicity. To overcome these barriers, researchers have turned to topical route of drug administration, which has superior patience compliance and they also bypass the first past effect experienced with conventional oral administration. Furthermore, to enhance the permeation of drug through the layers of the skin and reach the site of inflammation, nanosized carriers have been designed such as liposomes, nanoemulsions, niosomes, ethosomes, solid lipid nanoparticles and transferosomes. These drug delivery systems are non-toxic and have high drug encapsulation efficiency and they also provide sustained release of drug. This review discusses the effect of formulation composition on the physiochemical properties of these nanocarriers in terms of particle size, surface charge, drug entrapment and also drug release profile thus providing a landscape of topically used nanoformulations for symptomatic treatment of RA.

Intestinal barrier dysfunction plays an integral role in arthritis pathology and can be targeted to ameliorate disease

Background

Evidence suggests an important role for gut-microbiota dysbiosis in the development of rheumatoid arthritis (RA). The link between changes in gut bacteria and the development of joint inflammation is missing. Here, we address whether there are changes to the gut environment and how they contribute to arthritis pathogenesis.

Methods

We analyzed changes in markers of gut permeability, damage, and inflammation in peripheral blood and serum of RA patients. Serum, intestines, and lymphoid organs isolated from K/BxN mice with spontaneous arthritis or from wild-type, genetically modified interleukin (IL)-10R^−/−or claudin-8^−/−mice with induced arthritis were analyzed by immunofluorescence/histology, ELISA, and flow cytometry.

Findings

RA patients display increased levels of serum markers of gut permeability and damage and cellular gut-homing markers, both parameters positively correlating with disease severity. Arthritic mice display increased gut permeability from early stages of disease, as well as bacterial translocation, inflammatory gut damage, increases in interferon γ (IFNγ)⁺and decreases in IL-10⁺intestinal-infiltrating leukocyte frequency, and reduced intestinal epithelial IL-10R expression. Mechanistically, both arthritogenic bacteria and leukocytes are required to disrupt gut-barrier integrity. We show that exposing intestinal organoids to IFNγ reduces IL-10R expression by epithelial cells and that mice lacking epithelial IL-10R display increased intestinal permeability and exacerbated arthritis. Claudin-8^−/−mice with constitutively increased gut permeability also develop worse joint disease. Treatment of mice with AT-1001, a molecule that prevents development of gut permeability, ameliorates arthritis.

Conclusions

We suggest that breakdown of gut-barrier integrity contributes to arthritis development and propose restoration of gut-barrier homeostasis as a new therapeutic approach for RA.

Funding

Funded by Versus Arthritis (21140 and 21257) and UKRI/MRC (MR/T000910/1).

Serum gut-permeability markers LPB, LPS, and I-FABP are increased in RA

Mice with arthritis have increased gut permeability and intestinal inflammation

Both bacteria and leukocytes are needed to disrupt gut-barrier integrity

Prevention of gut-barrier dysfunction in arthritis ameliorates joint inflammation

Rheumatoid arthritis is an autoimmune disorder characterized by chronic joint inflammation. Accumulating evidence suggests that changes in the composition of the bacteria residing in the gut could be responsible for joint inflammation. Currently, it is unclear how bacteria or their products instruct cells of the immune system to become harmful and induce arthritis. Researchers at University College London have shown that, in arthritis, there is profound damage to the gut lining, which fails to work properly as a barrier, as well as an accumulation in the gut of white blood cells that cause inflammation. The authors show that, in arthritis, bacteria cross the prohibited border of the intestinal lining and that repairing gut permeability defects with specific drugs inhibits joint inflammation.

Anti-Inflammatory Therapy for Atherosclerosis: Focusing on Cytokines

Atherosclerosis is a well-known global health problem. Despite the high prevalence of the disease, numerous aspects of pathogenesis remain unclear. Subsequently, there are still no cure or adequate preventive measures available. Atherogenesis is now considered a complex interplay between lipid metabolism alterations, oxidative stress, and inflammation. Inflammation in atherogenesis involves cellular elements of both innate (such as macrophages and monocytes) and adaptive immunity (such as B-cells and T-cells), as well as various cytokines cascades. Because inflammation is, in general, a well-investigated therapeutic target, and strategies for controlling inflammation have been successfully used to combat a number of other diseases, inflammation seems to be the preferred target for the treatment of atherosclerosis as well. In this review, we summarized data on targeting the most studied inflammatory molecular targets, CRP, IL-1β, IL-6, IFN-γ, and TNF-α. Studies in animal models have shown the efficacy of anti-inflammatory therapy, while clinical studies revealed the incompetence of existing data, which blocks the development of an effective atheroprotective drug. However, all data on cytokine targeting give evidence that anti-inflammatory therapy can be a part of a complex treatment.

The Therapeutic Landscape of Rheumatoid Arthritis: Current State and Future Directions

Rheumatoid arthritis (RA) is a debilitating autoimmune disease with grave physical, emotional and socioeconomic consequences. Despite advances in targeted biologic and pharmacologic interventions that have recently come to market, many patients with RA continue to have inadequate response to therapies, or intolerable side effects, with resultant progression of their disease. In this review, we detail multiple biomolecular pathways involved in RA disease pathogenesis to elucidate and highlight pathways that have been therapeutic targets in managing this systemic autoimmune disease. Here we present an up-to-date accounting of both emerging and approved pharmacological treatments for RA, detailing their discovery, mechanisms of action, efficacy, and limitations. Finally, we turn to the emerging fields of bioengineering and cell therapy to illuminate possible future targeted therapeutic options that combine material and biological sciences for localized therapeutic action with the potential to greatly reduce side effects seen in systemically applied treatment modalities.

Therapeutic use of specific tumour necrosis factor inhibitors in inflammatory diseases including COVID-19

Coronavirus disease 2019 (COVID-19) has caused significant devastation globally. Despite the development of several vaccines, with uncertainty around global uptake and vaccine efficacy, the need for effective therapeutic agents remains. Increased levels of cytokines including tumour necrosis factor are significant in the pathogenesis of COVID-19 and associated with poor outcomes including ventilator requirement and mortality. Repurposing tumour necrosis factor blocker therapy used in conditions such as rheumatoid arthritis and inflammatory bowel disease seems promising, with early feasibility data showing a reduction in circulation of pro-inflammatory cytokines and encouraging the evaluation of such interventions in preventing disease progression and clinical deterioration in patients with COVID-19. Here, we examine the biological activities of tumour necrosis factor inhibitors indicative of their potential in COVID-19 and briefly outline the randomised control trials assessing their benefit-risk profile in COVID-19 therapy.

New therapeutic approaches of mesenchymal stem cells-derived exosomes

Mesenchymal stem cells (MSCs) have been demonstrated to have a great potential in the treatment of several diseases due to their differentiation and immunomodulatory capabilities and their ability to be easily cultured and manipulated. Recent investigations revealed that their therapeutic effect is largely mediated by the secretion of paracrine factors including exosomes. Exosomes reflect biophysical features of MSCs and are considered more effective than MSCs themselves. Alternative approaches based on MSC-derived exosomes can offer appreciable promise in overcoming the limitations and practical challenges observed in cell-based therapy. Furthermore, MSC-derived exosomes may provide a potent therapeutic strategy for various diseases and are promising candidates for cell-based and cell-free regenerative medicine. This review briefly summarizes the development of MSCs as a treatment for human diseases as well as describes our current knowledge about exosomes: their biogenesis and molecular composition, and how they exert their effects on target cells. Particularly, the therapeutic potential of MSC-derived exosomes in experimental models and recent clinical trials to evaluate their safety and efficacy are summarized in this study. Overall, this paper provides a current overview of exosomes as a new cell-free therapeutic agent.

Long-term Use of Golimumab in Daily Practice for Patients with Rheumatoid Arthritis

Objective To evaluate the effectiveness and drug retention rate of golimumab (GLM) for long-term use in daily practice for patients with rheumatoid arthritis (RA). Methods Patients with RA who started GLM therapy with a minimum follow-up period of 52 weeks were included. The patients were divided into a biologic-naïve group and switch group. The disease activity score (DAS) 28-erythrocyte sedimentation rate (ESR) (DAS28-ESR), grip power, and Japanese version of the health assessment questionnaire (J-HAQ) score were assessed. In addition, the treatment continuation rate was evaluated at the final follow-up. Patients Sixty-five patients [58 women and 7 men; median (range) age, 69 (61-74) years; median (range) disease duration, 9 (5-16) years] were included. Twenty-eight patients were biologic-naïve (naïve group), and 37 were switched to biologics (switch group). Results The median (range) follow-up period was 134 (58-162) weeks. The DAS28-ESR improved from a median (range) of 4.31 (3.52-5.25) to 2.65 (2.28-3.77) in the naïve group and from 4.27 (3.19-4.89) to 2.89 (2.49-3.88) in the switch group. The grip power improved in both groups (p<0.01); however, the J-HAQ score showed no marked improvement in either group. The continuation rates were 22/28 (78.6%) in the naïve group, and 26/37 (70.3%) in the switch group at the final follow-up. Conclusion We herein report for the first time that the long-term use of GLM improves the grip power. Improving the grip power may help prevent sarcopenia and frailty in the future. Given the efficacy and high continuation rate, we suggest that GLM would be a well-tolerated treatment option for RA.

Deciphering Role of Cytokines for Therapeutic Strategies Against Rheumatoid Arthritis

Rheumatoid Arthritis (RA) is a systemic, chronic, autoimmune, inflammatory disorder that affects both large and small synovial joints in a symmetric pattern. RA initiates as painful inflammation of the joints leading to stiffness of joint, joint destruction and further worsens the condition causing permanent irreversible damage to the joints, making them physically disabled. Across the globe, there are around 1.2 million cases of RA reported. Inspite of various available therapeutic and pharmacological agents against RA, none of the treatments assure complete cure. Understanding the in depth-role of cytokines and interleukins in the disease pathogenesis of RA could help in exploiting them for developing novel therapeutic strategies against RA. This review provides insights into the pathogenesis of RA and gives a brief overview of cytokines, which play an important role in the progression of the disease. We have also discussed the possible role of interleukins in the context of RA, which could help future researchers to explore them for identifying new therapeutic agents.

Recombinant Adiponectin Induces the Production of Pro-Inflammatory Chemokines and Cytokines in Circulating Mononuclear Cells and Fibroblast-Like Synoviocytes From Non-Inflamed Subjects

Adiponectin is an adipokine with a modulatory role in metabolism and exerting both anti- and pro-inflammatory effects. Levels of adiponectin are increased in serum and synovial fluid from patients with rheumatoid arthritis (RA). Adiponectin is able to stimulate the production of different pro-inflammatory factors from peripheral blood mononuclear cells (PBMCs) and fibroblast-like synoviocytes (FLS) from subjects with established RA. As increased circulating adiponectin levels are a risk factor for future development of RA in subjects with obesity, we hypothesize that adiponectin is implicated in the development of RA at an early stage by initiating the pro-inflammatory processes associated with the disease pathogenesis. Therefore, we aimed to determine if adiponectin is able to induce pro-inflammatory responses in cells involved in the pathogenesis of RA, but collected from subjects without any known inflammatory disease. PBMCs and FLS were obtained from non-inflamed subjects and stimulated with 5 μg/ml human recombinant adiponectin. Supernatants collected after 48 h were analyzed for the production of 13 chemokines and 12 cytokines using multiplex assay and ELISA. Adiponectin significantly stimulated the production of CXCL1, CXCL5, and interleukin (IL)-6 in both PBMCs and FLS, whereas it induced CCL20, CCL4, CCL3, CCL17, tumor necrosis factor (TNF), granulocyte-macrophage colony-stimulating factor and IL-10 only in PBMCs, and CXCL8, CXCL10, CCL5, CCL11, and CCL2 only in FLS. Pre-stimulation with TNF of FLS from non-inflamed subjects did not significantly enhance the release of most pro-inflammatory factors compared to adiponectin alone. Our findings indicate that PBMCs and FLS from non-inflamed subjects react to adiponectin stimulation with the secretion of several pro-inflammatory chemokines and cytokines. These results suggest that adiponectin is able to initiate pro-inflammatory responses in cells from non-inflamed subjects and support the hypothesis that adiponectin is implicated in the early phases of RA pathogenesis.

Tumor necrosis factor in lung cancer: Complex roles in biology and resistance to treatment

Tumor necrosis factor (TNF) and its receptors are widely expressed in non-small cell lung cancer (NSCLC). TNF has an established role in inflammation and also plays a key role in inflammation-induced cancer. TNF can induce cell death in cancer cells and has been used as a treatment in certain types of cancer. However, TNF is likely to play an oncogenic role in multiple types of cancer, including NSCLC. TNF is a key activator of the transcription factor NF-κB. NF-κB, in turn, is a key effector of TNF in inflammation-induced cancer. Data from The Cancer Genome Atlas database suggest that TNF could be a biomarker in NSCLC and indicate a complex role for TNF and its receptors in NSCLC. Recent studies have reported that TNF is rapidly upregulated in NSCLC in response to targeted treatment with epidermal growth factor receptor (EGFR) inhibition, and this upregulation leads to NF-κB activation. The TNF upregulation and consequent NF-κB activation play a key role in mediating both primary and secondary resistance to EGFR inhibition in NSCLC, and a combined inhibition of EGFR and TNF can overcome therapeutic resistance in experimental models. TNF may mediate the toxic side effects of immunotherapy and may also modulate resistance to immune checkpoint inhibitors. Drugs inhibiting TNF are widely used for the treatment of various inflammatory and rheumatologic diseases and could be quite useful in combination with targeted therapy of NSCLC and other cancers.

High-Throughput CRISPR Screening Identifies Genes Involved in Macrophage Viability and Inflammatory Pathways

Macrophages are critical effector cells of the immune system, and understanding genes involved in their viability and function is essential for gaining insights into immune system dysregulation during disease. We use a high-throughput, pooled-based CRISPR-Cas screening approach to identify essential genes required for macrophage viability. In addition, we target 3' UTRs to gain insights into previously unidentified cis-regulatory regions that control these essential genes. Next, using our recently generated nuclear factor κB (NF-κB) reporter line, we perform a fluorescence-activated cell sorting (FACS)-based high-throughput genetic screen and discover a number of previously unidentified positive and negative regulators of the NF-κB pathway. We unravel complexities of the TNF signaling cascade, showing that it can function in an autocrine manner in macrophages to negatively regulate the pathway. Utilizing a single complex library design, we are capable of interrogating various aspects of macrophage biology, thus generating a resource for future studies.

Aberrant expression of USF2 in refractory rheumatoid arthritis and its regulation of proinflammatory cytokines in Th17 cells

IL-17-producing Th17 cells are implicated in the pathogenesis of rheumatoid arthritis (RA) and TNF-α, a proinflammatory cytokine in the rheumatoid joint, facilitates Th17 differentiation. Anti-TNF therapy ameliorates disease in many patients with rheumatoid arthritis (RA). However, a significant proportion of patients do not respond to this therapy. The impact of anti-TNF therapy on Th17 responses in RA is not well understood. We conducted high-throughput gene expression analysis of Th17-enriched CCR6+CXCR3-CD45RA- CD4+ T (CCR6+ T) cells isolated from anti-TNF-treated RA patients classified as responders or nonresponders to therapy. CCR6+ T cells from responders and nonresponders had distinct gene expression profiles. Proinflammatory signaling was elevated in the CCR6+ T cells of nonresponders, and pathogenic Th17 signature genes were up-regulated in these cells. Gene set enrichment analysis on these signature genes identified transcription factor USF2 as their upstream regulator, which was also increased in nonresponders. Importantly, short hairpin RNA targeting USF2 in pathogenic Th17 cells led to reduced expression of proinflammatory cytokines IL-17A, IFN-γ, IL-22, and granulocyte-macrophage colony-stimulating factor (GM-CSF) as well as transcription factor T-bet. Together, our results revealed inadequate suppression of Th17 responses by anti-TNF in nonresponders, and direct targeting of the USF2-signaling pathway may be a potential therapeutic approach in the anti-TNF refractory RA.

Flare-up of cytokines in rheumatoid arthritis and their role in triggering depression: Shared common function and their possible applications in treatment (Review)

Chronic illnesses are associated with an increased risk of depression and anxiety. Rheumatoid arthritis (RA) is a chronic autoimmune disease that typically causes damage to the joints. RA extensively impacts patients, both physically and psychologically. Depression is a common comorbid disorder with RA, which leads to worsened health outcomes. There are several cytokines that are active in the joints of patients with RA. Inflammatory cytokines serve important roles in the key processes in the joints, which usually cause inflammation, articular damage and other comorbidities associated with RA. The key role of inflammatory cytokines could be attributed to their interactions within signaling pathways. In RA, IL-1, and the cytokines of TNF-α, IL-6 and IL-18 are primarily involved. Furthermore, depression is hypothesized to be strongly associated with systemic inflammation, particularly with dysregulation of the cytokine network. The present review summarizes the current state of knowledge on these two diseases from the perspective of inflammation and cytokines, and emphasizes the possible bridge between them by exploring the involvement of systemic cytokines in both conditions.

Variability in the Laboratory Measurement of Cytokines

CONTEXT.—

The measurement of cytokines in clinical laboratories is becoming an increasingly routine part of immune monitoring when administering biologic and cell-based immunotherapies and also for clinical assessment of inflammatory conditions. While a number of commercial assays and platforms are available for cytokine measurement, there is currently little standardization among these analytical methods.

OBJECTIVE.—

To characterize the variability and comparability among cytokine testing platforms that are commonly used in clinical laboratories.

DESIGN.—

We analyzed data for 4 cytokines (interleukin [IL]-1, IL-6, IL-8, and tumor necrosis factor-alpha [TNF-α]) from 6 College of American Pathologists cytokine surveys administered from 2015 to 2018. Analyses interrogated variability between testing methods and variability within each laboratory across the mailings.

RESULTS.—

Significant variability was noted across methods with analysis of IL-1 showing the least variability and IL-6, IL-8, and TNF-α varying between methods to a greater extent. Intralab variability was also significant with TNF-α measurements again showing the greatest variability.

CONCLUSIONS.—

This retrospective analysis of College of American Pathologists proficiency testing data for cytokine measurement is the largest method comparison to date, and this study provides a description of the variation of cytokine measurement across methods, across laboratories, and within laboratories. Serial monitoring of cytokines should preferentially be performed by the same method within the same laboratory.

Brain TNF drives post-inflammation depression-like behavior and persistent pain in experimental arthritis

Patients with rheumatoid arthritis experience chronic pain, depression and fatigue, even when inflammation of the joints is well controlled. To study the relationship between arthritis, depression, and sustained pain when articular inflammation is no longer observed, we tested the hypothesis that brain TNF drives post-inflammation depression-like behavior and persistent pain in experimental arthritis. The murine model of antigen-induced arthritis (AIA) was used to evaluate the effects of knee inflammation on sustained pain and depression-like behavior. We measured joint pain using an automated dynamic plantar algesiometer and depression-like behavior with the tail suspension test. Cytokines were measured by Luminex assay and ELISA. TNF in the brain was blocked by intracerebroventricular injection of anti-TNF antibodies. Histological damage and elevated levels of cytokines were observed in the knee 24 h after antigen treatment, but not at 13 days. Reduced pain thresholds were seen 24 h and 13 days after treatment. Depression-like behavior was observed on day 13. Treatment with the antidepressant imipramine reduced both depression-like behavior and persistent pain. However, blocking joint pain with the analgesic dipyrone did not alter depression-like behavior. Elevated levels of TNF, CCL2, and CXCL-1 were observed in the hippocampus 24 h after treatment, with TNF remaining elevated at day 13. Intracerebroventricular infusion of an anti-TNF antibody blocked depression-like behavior and reduced persistent pain. We have demonstrated that depression-like behavior and pain is sustained in AIA mice after the resolution of inflammation. These changes are associated with elevated levels of TNF in the hippocampus and are dependent upon brain TNF. The findings reveal an important mechanistic link between the expression of chronic pain and depression in experimental arthritis. Furthermore, they suggest treating depression in rheumatoid arthritis may positively impact other debilitating features of this condition.

Role of Infections in the Pathogenesis of Rheumatoid Arthritis: Focus on Mycobacteria

Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disease characterized by chronic erosive polyarthritis. A complex interaction between a favorable genetic background, and the presence of a specific immune response against a broad-spectrum of environmental factors seems to play a role in determining susceptibility to RA. Among different pathogens, mycobacteria (including Mycobacterium avium subspecies paratuberculosis, MAP), and Epstein–Barr virus (EBV), have extensively been proposed to promote specific cellular and humoral response in susceptible individuals, by activating pathways linked to RA development. In this review, we discuss the available experimental and clinical evidence on the interplay between mycobacterial and EBV infections, and the development of the immune dysregulation in RA.

Current and novel therapeutic targets in the treatment of rheumatoid arthritis

Rheumatoid arthritis (RA), a multifactorial disease characterized by synovitis, cartilage destruction, bone erosion, and periarticular decalcification, finally results in impairment of joint function. Both genetic and environmental factors are risk factors in the development of RA. Unwanted side effects accompany most of the current treatment strategies, and around 20-40% of patients with RA do not clinically benefit from these treatments. The unmet need for new treatment options for RA has prompted research in the development of novel agents acting through physiologically and pharmacologically relevant targets. Here we discuss in detail three critical pathways, Janus kinase/signal transducer and activator of transcription (JAK/STAT), Th17, and hypoxia-inducible factor (HIF), and their roles as unique therapeutic targets in the field of RA. Some of the less developed but potential targets like nucleotide-binding and oligomerization domain-like receptor containing protein 3 (NLRP3) inflammasome and histone deacetylase 1 (HDAC1) are also discussed.

Comparative Analysis of Multiple Immunoassays for Cytokine Profiling in Drug Discovery

Cytokines and their receptors play critical roles in biological processes. Dysfunction or dysregulation of cytokines may cause a variety of pathophysiological conditions. Consequently, cytokine profiling and related technologies are essential for biological studies, disease diagnosis, and drug discovery. In this report, three cytokines, interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha (TNF-α), from the same sets of samples were analyzed with several commonly used technologies (enzyme-linked immunosorbent assay [ELISA], Luminex, Meso Scale Discovery [MSD], time-resolved fluorescence resonance energy transfer [TR-FRET], cytometric bead array [CBA], AlphaLISA, and FirePlex). Through experimental data analysis, several assay features were compared, including sensitivity, dynamic range, and robustness. Our studies reveal that MSD has the best sensitivity in the low detection limit and the broadest dynamic range, while CBA and Luminex also demonstrate superior performance in the sensitivity and dynamic range. Additional aspects of these technologies, including assay principles, formats, throughputs, robustness, costs, and multiplexing capabilities, were also reviewed and compared. Combining all these features, our comparison highlights MSD as the most sensitive technology, while CBA is the most suitable one for cytokine high-throughput screening with multiplexing capability. Along with perspectives on new technology development in the field, this report aims to help readers understand these technologies and select the proper one for specific applications.

Dereplication and quantification of the ethanol extract of Miconia albicans (Melastomaceae) by HPLC-DAD-ESI-/MS/MS, and assessment of its anti-hyperalgesic and anti-inflammatory profiles in a mice arthritis-like model: Evidence for involvement of TNF-α, IL-1β and IL-6

ETHNOPHARMACOLOGICAL RELEVANCE

Miconia albicans (Sw) Triana (Melastomataceae), a medicinal plant widely used by practitioners of folk medicine in the northeast of Brazil, has been used to treat chronic inflammatory disorders, such as rheumatoid arthritis (RA) and other joint conditions. Oddly, there is little research on the species.

AIM OF THE STUDY

We aimed to evaluate the anti-arthritic and anti-inflammatory profile of the ethanolic leaf extract of M. albicans (EEMA), as well as to perform dereplication and quantification by HPLC-DAD-ESI-/MS/MS.

MATERIALS AND METHODS

The compounds present in the extracts were identified by HPLC-DAD-ESI-MS/MS. The possible anti-inflammatory effect of EEMA (50 and 100 mg/kg, p.o) was evaluated using the pleurisy model induced by carrageenan and its action on IL-1β and TNF-α levels was also evaluated. The RA model was induced through the intra-articular injection of complete Freund's adjuvant (CFA).

RESULTS

HPLC-DAD-ESI-MS/MS analysis identified 23 compounds, with glycoside flavonoids mainly derived from quercetin, and rutin being the main compounds. EEMA significantly reduced (p < 0.001) leukocyte migration in the pleurisy model and reduced TNF-α and IL-1β levels in pleural lavage (p < 0.001). In the CFA animal model, EEMA significantly reduced the nociceptive and hyperalgesic behaviors demonstrated by the rearing test (p < 0.01 or p < 0.05) and decreased mechanical hyperalgesia (p < 0.001). EEMA produced a significant improvement in mobility in the open-field test (only at the higher dose, p < 0.05). EEMA significantly (p < 0.01) increased hindpaw grip strength. The diameter of CFA-induced ipsilateral knee edema was significantly reduced (p < 0.001) by EEMA, which was related to reduced levels of IL-6 and TNF-α in the joint knee (p < 0.01). No indication of hepatic injury after chronic treatment was found.

CONCLUSION

Taken together, these results contribute to the chemical and pharmacological knowledge of M. albicans and demonstrated that this medicinal plant appears to be able to mitigate deleterious symptoms of RA, which supports its use in folk medicine.

Precision medicine for rheumatologists: lessons from the pharmacogenomics of azathioprine

Precision medicine aims to personalize treatment for both effectiveness and safety. As a critical component of this emerging initiative, pharmacogenomics seeks to guide drug treatment based on genetics. In this review article, we give an overview of pharmacogenomics in the setting of an immunosuppressant frequently prescribed by rheumatologists, azathioprine. Azathioprine has a narrow therapeutic index and a high risk of adverse events. By applying candidate gene analysis and unbiased approaches, researchers have identified multiple variants associated with an increased risk for adverse events associated with azathioprine, particularly bone marrow suppression. Variants in two genes, TPMT and NUDT15, are widely recognized, leading drug regulatory agencies and professional organizations to adopt recommendations for testing before initiation of azathioprine therapy. As more gene-drug interactions are discovered, our field will continue to face the challenge of balancing benefits and costs associated with genetic testing. However, novel approaches in genomics and the integration of clinical and genetic factors into risk scores offer unprecedented opportunities for the application of pharmacogenomics in routine practice. Key Points • Pharmacogenomics can help us understand how individuals' genetics may impact their response to medications. • Azathioprine is a success story for the clinical implementation of pharmacogenomics, particularly the effects of TPMT and NUDT15 variants on myelosuppression. • As our knowledge advances, testing and dosing recommendations will continue to evolve, with our field striving to balance costs and benefits to patients. • As we aim toward the goals of precision medicine, future research may integrate increasingly individualized traits-including clinical and genetic characteristics-to predict the safety and efficacy of particular medications for individual patients.

The Association between the Plasma Sugar and Lipid Profile with the Gene Expression of the Regulatory Protein of mTOR (Raptor) in Patients with Rheumatoid Arthritis

BACKGROUND

Rheumatoid arthritis (RA) is an autoinflammatory and self-perpetuating disease with both articular and extra-articular manifestations, such as cardiovascular complications, which are the leading cause of mortality and morbidity in RA patients. Impaired sugar and lipid metabolism are considered as the critical risk factors for cardiovascular disease (CVD). Regarding the regulatory function of Raptor in the immunometabolism, in this study, we evaluated the association between plasma sugar and lipid profiles with the gene expression of Raptor and the cytokine tumor necrosis factor-α (TNF-α), as an inflammatory mediator, in peripheral blood leukocyte of RA patients.

MATERIAL AND METHODS

Thirty-five RA patients who received combinational disease modified anti-rheumatoid drugs (DMARD) regimen and thirty healthy subjects enrolled in this study. The gene expression of Raptor was assessed by the real-time PCR method, and the Plasma levels of glucose and lipids, as well as TNF-α, were obtained using Hitachi device and enzyme-linked immunosorbent assay (ELISA) technique, respectively.

RESULTS

The gene expression of Raptor was reduced significantly in RA patients compared to the healthy subjects (p = .001). The plasma level of HDL was significantly higher in RA patients than the control group (p = .001), while the plasma level of LDL was reduced significantly in these patients (p = .001).

CONCLUSION

In our study, the reduced gene expression of Raptor may contribute to the impaired immunometabolism in RA patients, which is independent of plasma sugar and lipid profile.

Impact of persistence with tumour necrosis factor inhibitors on healthcare resource utilization and costs in chronic inflammatory joint diseases

AIM

To assess persistence with subcutaneous (SC) tumour necrosis factor (TNF) inhibitors as well as the impact of persistence on healthcare resource utilization (HCRU) and costs in patients with chronic inflammatory joint diseases.

METHODS

In this cohort study using population-based French claims data (from 2011 to 2014), we measured persistence with SC TNF inhibitors within 12 months (M0-12) following treatment initiation in treatment-naïve and treatment-experienced users (divided into three cohorts: rheumatoid arthritis [RA], ankylosing spondylitis [AS] and psoriatic arthritis [PsA]). Persistent patients were propensity score matched to nonpersistent patients at M12. The impact of persistence status on HCRU and costs was assessed during M12-24.

RESULTS

Of treatment-naïve (n = 3,804) and treatment-experienced (n = 2,279) users, only 56.1% and 46.8% were persistent at M12, respectively. Nonpersistent patients had more outpatient visits, computerized tomography scans, spine or joint magnetic resonance imaging procedures and disease-related hospitalizations, while persistent patients had more rheumatologist visits. Nonpersistent patients had lower drug costs but higher nondrug-related healthcare and hospitalization costs than persistent patients. In AS and PsA, overall healthcare costs were similar in persistent and nonpersistent patients. In RA, overall healthcare costs were lower in persistent patients (15,753€ vs 17,590€ in treatment-naïve and 17,622€ vs 21,177€ in treatment-experienced).

CONCLUSION

Persistence with SC TNF inhibitors within first 12 months following treatment initiation was low in both treatment-naïve and treatment-experienced patients. Differences were observed in distribution of costs between persistent and nonpersistent patients, showing that nonpersistence with SC TNF inhibitors can lead to increased HCRU and higher costs.

The effect of smoking on disease activity in rheumatoid arthritis - our experience

The aim of this study was to investigate the association of smoking with disease activity, seropositivity, age and gender in patients with rheumatoid arthritis. We included 89 rheumatoid arthritis patients. All patients fulfilled the 2010 American College of Rheumatology/European League Against Rheumatism rheumatoid arthritis classification criteria. Activity of the disease was measured by Disease Activity Score 28-joint count C-reactive protein (DAS28CRP). The subjects were stratified into smoking and non-smoking groups and cross-sectionally analyzed. There were 24 (27%) smokers and 65 (73%) nonsmokers. The mean age of patients was 57.1±8.8 years. The mean DAS28CRP was 5.81 in the smoking group and 5.57 in the non-smoking group, without statistically significant difference between the two groups (p=0.148). Similarly, smokers did not differ significantly from non-smokers according to age (p=0.443), gender (p=0.274), rheumatoid factor positivity (p=0.231), anti-citrullinated protein antibody positivity (p=0.754) or seropositivity (p=0.163). In this study, we found no association between smoking status and disease activity, seropositivity, age or gender in rheumatoid arthritis patients. Furthermore, disease activity was not related to age, gender or seropositivity. Additional studies on the effects of smoking on rheumatoid arthritis activity are needed.

Inhibition of Osteoclastogenesis by the RNA-Binding Protein QKI5: a Novel Approach to Protect from Bone Resorption

Increased osteoclastogenesis is a common feature of bone erosion, notably in osteoporosis but also in inflammatory diseases such as rheumatoid arthritis (RA) and osteoarticular infections. Human cytomegalovirus (HCMV) infection has been described to impair monocyte differentiation into macrophages and dendritic cells. However, its effect on monocyte-derived osteoclasts is yet to be determined. We showed here that in vitro HCMV infection is associated with an inhibition of osteoclastogenesis through decreased expression of colony stimulating factor 1 receptor (CSF-1R) and RANK in monocytes, which was mediated by an upregulation of quaking I-5 protein (QKI-5), a cellular RNA-interacting protein. We found that deliberate QKI5 overexpression in the absence of HCMV infection is able to decrease CSF-1R and RANK expression, leading to osteoclastogenesis inhibition. Finally, by using lentiviral vectors in a calvarial bone erosion mouse model, we showed that QKI5 inhibits bone degradation. This work identifies QKI5 as a strong inhibitor of bone resorption. Future research will point out whether QKI5 could be a target for bone pathologies. © 2019 American Society for Bone and Mineral Research.

Designing a new dimerized anti human TNF-α aptamer with blocking activity

The human tumor necrosis factor α (hTNF-α) is an important pro-inflammatory cytokine which plays critical roles in inflammatory diseases such as rheumatoid arthritis (RA). The anti-TNF-α proteins can reduce symptoms of RA. Due to limitations of protein-based therapies, it is necessary to find new anti-TNF-α agents instead of common anti-TNF-α proteins. Therefore, the aim of the current study was to identify a new DNA aptamer with anti-hTNF-α activity. The protein systematic evolution of ligands by exponential enrichment (SELEX) process was used for identifying DNA aptamers. Anti-hTNF-α aptamers were selected using dot blot, real-time PCR, and in vitro inhibitory assay. The selected aptamers were truncated in two steps, and finally, a dimer aptamer was constructed from different selected truncates to improve their inhibitory effect. Also, Etanercept was used as a positive control to inhibit TNF-α, in comparison to the designed aptamers. After 11 rounds, four aptamers with anti-hTNF-α inhibitory effect were identified. The truncation and dimerization strategy revealed a new dimer aptamer with 67 nM K_d , which has 40% inhibitory effect compared with Etanercept (60%). Overall, the dimerization and truncation aptamers could improve its activity. With regard to the several limitations of anti-TNF-α proteins therapies including immunogenicity, side effects, and cost-intensive, a new designed anti-hTNF-α dimer aptamer could be considered as a potential therapeutic and/or diagnostic agent for hTNF-α-related disorders.

Pharmacological targets of metabolism in disease: Opportunities from macrophages

From advances in the knowledge of the immune system, it is emerging that the specialized functions displayed by macrophages during the course of an immune response are supported by specific and dynamically-connected metabolic programs. The study of immunometabolism is demonstrating that metabolic adaptations play a critical role in modulating inflammation and, conversely, inflammation deeply influences the acquisition of specific metabolic settings.This strict connection has been proven to be crucial for the execution of defined immune functional programs and it is now under investigation with respect to several human disorders, such as diabetes, sepsis, cancer, and autoimmunity. The abnormal remodelling of the metabolic pathways in macrophages is now emerging as both marker of disease and potential target of therapeutic intervention. By focusing on key pathological conditions, namely obesity and diabetes, rheumatoid arthritis, atherosclerosis and cancer, we will review the metabolic targets suitable for therapeutic intervention in macrophages. In addition, we will discuss the major obstacles and challenges related to the development of therapeutic strategies for a pharmacological targeting of macrophage's metabolism.

B cells in rheumatoid arthritis synovial tissues encode focused antibody repertoires that include antibodies that stimulate macrophage TNF-α production

Rheumatoid arthritis (RA) is characterized by the production of anti-citrullinated protein antibodies (ACPAs). To gain insights into the relationship between ACPA-expressing B cells in peripheral blood (PB) and synovial tissue (ST), we sequenced the B cell repertoire in paired PB and ST samples from five individuals with established, ACPA+ RA. Bioinformatics analysis of paired heavy- and light-chain sequences revealed clonally-related family members shared between PB and ST. ST-derived antibody repertoires exhibited reduced diversity and increased normalized clonal family size compared to PB-derived repertoires. Functional characterization showed that seven recombinant antibodies (rAbs) expressed from subject-derived sequences from both compartments bound citrullinated antigens and immune complexes (ICs) formed using one ST-derived rAb stimulated macrophage TNF-α production. Our findings demonstrate B cell trafficking between PB and ST in subjects with RA and ST repertoires include B cells that encode ACPA capable of forming ICs that stimulate cellular responses implicated in RA pathogenesis.

Inhibition of tumor necrosis factor-α enhanced the antifibrotic effect of empagliflozin in an animal model with renal insulin resistance

Insulin resistance (IR) has emerged as one of the main risk factors for renal fibrosis (RF) that represents a common stage in almost all chronic kidney disease. The present study aims to investigate the inhibitory effect of empagliflozin (EMPA "a sodium-glucose co-transporter 2 inhibitor") and infliximab [IFX "a tumor necrosis factor-α (TNF-α) antibody"] on RF in rats with induced IR. IR was induced by adding 10% fructose in drinking water for 20 weeks. Thereafter, fructose-induced IR rats were concurrently treated with EMPA (30 mg/kg), IFX (1 dose 5 mg/kg), or EMPA + IFX for 4 weeks, in addition to IR control group (received 10% fructose in water) and normal control (NC) group. Rats with IR displayed hyperglycemia, deterioration in kidney functions, glomerulosclerosis, and collagen fiber deposition in renal tissues as compared to NC. This was associated with downregulation of the renal sirtuin 1 (Sirt 1) expression along with higher renal tissue TNF-α and transforming growth factor-β1 (TGF-β1) levels. Both EMPA and IFX significantly modulated the aforementioned fibrotic cytokines, upregulated the renal Sirt 1 expression, and attenuated RF compared to IR control group. Of note, IFX effect was superior to that of EMPA. However, the combination of EMPA and IFX alleviated RF to a greater extent surpassing the monotherapy. This may be attributed to the further upregulation of renal Sirt 1 in addition to the downregulation of fibrotic cytokines. These findings suggest that the combination of EMPA and IFX offers additional benefits and may represent a promising therapeutic option for RF.

The Novel Synthetic Peptide AESIS-1 Exerts a Preventive Effect on Collagen-Induced Arthritis Mouse Model via STAT3 Suppression

Rheumatoid arthritis (RA) is a chronic autoimmune disease that is associated with systemic inflammation and results in the destruction of joints and cartilage. The pathogenesis of RA involves a complex inflammatory process resulting from the action of various proinflammatory cytokines and, therefore, many novel therapeutic agents to block cytokines or cytokine-mediated signaling have been developed. Here, we tested the preventive effects of a small peptide, AESIS-1, in a mouse model of collagen-induced arthritis (CIA) with the aim of identifying a novel safe and effective biological for treating RA. This novel peptide significantly suppressed the induction and development of CIA, resulting in the suppression of synovial inflammation and cartilage degradation in vivo. Moreover, AESIS-1 regulated JAK/STAT3-mediated gene expression in vitro. In particular, the gene with the most significant change in expression was suppressor of cytokine signaling 3 (Socs3), which was enhanced 8-fold. Expression of the STAT3-specific inhibitor, Socs3, was obviously enhanced dose-dependently by AESIS-1 at both the mRNA and protein levels, resulting in a significant reduction of STAT3 phosphorylation in splenocytes from severe CIA mice. This indicated that AESIS-1 regulated STAT3 activity by upregulation of SOCS3 expression. Furthermore, IL-17 expression and the frequency of Th17 cells were considerably decreased by AESIS-1 in vivo and in vitro. Collectively, our data suggest that the novel synthetic peptide AESIS-1 could be an effective therapeutic for treating RA via the downregulation of STAT3 signaling.

RA-map: building a state-of-the-art interactive knowledge base for rheumatoid arthritis

Rheumatoid arthritis (RA) is a progressive, inflammatory autoimmune disease of unknown aetiology. The complex mechanism of aetiopathogenesis, progress and chronicity of the disease involves genetic, epigenetic and environmental factors. To understand the molecular mechanisms underlying disease phenotypes, one has to place implicated factors in their functional context. However, integration and organization of such data in a systematic manner remains a challenging task. Molecular maps are widely used in biology to provide a useful and intuitive way of depicting a variety of biological processes and disease mechanisms. Recent large-scale collaborative efforts such as the Disease Maps Project demonstrate the utility of such maps as versatile tools to organize and formalize disease-specific knowledge in a comprehensive way, both human and machine-readable. We present a systematic effort to construct a fully annotated, expert validated, state-of-the-art knowledge base for RA in the form of a molecular map. The RA map illustrates molecular and signalling pathways implicated in the disease. Signal transduction is depicted from receptors to the nucleus using the Systems Biology Graphical Notation (SBGN) standard representation. High-quality manual curation, use of only human-specific studies and focus on small-scale experiments aim to limit false positives in the map. The state-of-the-art molecular map for RA, using information from 353 peer-reviewed scientific publications, comprises 506 species, 446 reactions and 8 phenotypes. The species in the map are classified to 303 proteins, 61 complexes, 106 genes, 106 RNA entities, 2 ions and 7 simple molecules. The RA map is available online at ramap.elixir-luxembourg.org as an open-access knowledge base allowing for easy navigation and search of molecular pathways implicated in the disease. Furthermore, the RA map can serve as a template for omics data visualization.

Efficacy and safety of Ramucirumab and methotrexate co-therapy in rheumatoid arthritis experimental model: Involvement of angiogenic and immunomodulatory signaling

Rheumatoid arthritis (RA) is a chronic and progressive autoimmune inflammatory disease associated with irreversible joint destruction that leads to permanent motor disability and compromised quality of life. However, the main cause of RA is still unknown though stimulation of immune system and cells plays pivotal role in disease development and progression. Ramucirumab (RAM) is the monoclonal antibody against VEGF- receptor. This study aimed to investigate and evaluate the therapeutic effect of RAM with or without Methotrexate (MTX) against adjuvant-induced arthritis in rats. Complete Freund's adjuvant (CFA)-induced arthritic rats were treated for three consecutive weeks with MTX or RAM alone and MTX-RAM co-therapy. Arthritic score, gait score, ankle diameter, paw thickness, angiogenic, inflammatory cytokines, bone erosion markers, and apoptotic markers were assessed to evaluate the anti-arthritic effect. RAM monotherapy exhibited anti-inflammatory, anti-angiogenic and anti-apoptotic effects similar to MTX alone to treat RA in the current study. Furthermore, RAM alone had a protective effect on bone and cartilage health better than standard anti-rheumatic agent MTX. Interestingly, combined therapy of MTX and RAM produced significant differences in comparison with MTX or RAM monotherapy in all tested parameters. Moreover, the current study proved that MTX-RAM co-therapy has a synergistic effect.

Pharmacogenetics: A strategy for personalized medicine for autoimmune diseases

For many years, a considerable number of patients with autoimmune diseases (ADs) have suffered from a lack of drug response and drug-related toxicity. Despite the emergence of new therapeutic options such as biological agents, patients continue to struggle with these problems. Unfortunately, new challenges, including the paradoxical effects of biological drugs, have complicated the situation. In recent decades, efforts have been made to predict drug response as well as drug-related side effects. Thanks to the many advances in genetics, evaluation of markers to predict drug response/toxicity before the initiation of treatment may be an avenue toward personalizing treatments. Implementing pharmacogenetics and pharmacogenomics in the clinic could improve clinical care; however, obstacles remain to effective personalized medicine for ADs. The present study attempted to clarify the concept of pharmacogenetics/pharmacogenomics for ADs. After an overview on the pathogenesis of the most common types of treatments, this paper focuses on pharmacogenetic studies related to the selected ADs. Bridging the gap between pharmacogenetics and personalized medicine is also discussed. Moreover, the advantages, disadvantages and recommendations related to making personalized medicine practical for ADs have been addressed.

Synovial Tissue Inflammation Mediated by Autoimmune T Cells

In rheumatoid arthritis (RA), various hematopoietic and non-hematopoietic cells present in the synovial tissue secrete numerous inflammatory mediators including pro-inflammatory cytokines critical for the induction of chronic joint inflammation and bone destruction. Fibroblast-like synoviocytes (FLSs) in the non-hematopoietic cell compartment are key inflammatory cells activated in inflamed joints and driving the disease; yet how synovial tissue inflammation is modulated by autoimmune T cells is not fully understood. In this review, mainly based on recent findings with a mouse model of spontaneous autoimmune arthritis, we discuss the mechanism of Th17-mediated synovial tissue inflammation; that is, what environmental stimuli and arthritogenic self-antigens trigger arthritis, how arthritogenic T cells initiate joint inflammation by stimulating FLSs, and how the cellular sources of GM-CSF from lymphoid and tissue stromal cells in the synovium contribute to the development of arthritis. We also highlight possible plasticity of Th17 cells toward pathogenic GM-CSF producers, and the functional instability of regulatory T cells under inflammatory conditions in RA joints.

Development and Characterization of a Potent Tumor Necrosis Factor-Alpha-Blocking Agent

Tumor necrosis factor-α (TNFα), one of the major proinflammatory cytokines, plays a key role in an effective immune response. However, the chronic presence of TNFα can lead to several inflammatory disorders, such as rheumatoid arthritis, psoriasis, Crohn's disease, etc. Inhibition of TNFα by pharmacological inhibitors or antibodies has proven to be effective in palliative treatment to some extent. The aim of this study was to develop an anti-TNFα antibody, which may be used as a therapeutic option to inhibit TNFα-mediated cytotoxicity. We characterized several hybridoma clones secreting monoclonal antibodies (mAbs) to human-TNFα. Four mAbs rescued L929 fibroblast cells from TNFα-triggered cell death and one of these, namely C8, was found to have the highest affinity. To gain insights into the mechanism by which mAb C8 inhibits human TNFα-mediated toxicity, the epitope corresponding to the mAb was delineated. The antigenic determinant was found to comprise of the stretch of amino acids 99-120, of which, 102-104 (glutamine, arginine, glutamic acid) form the core epitope. The observation was supported by bioinformatics analyses of an antigen/antibody complex model. In addition, the binding affinity of mAb C8 to TNFα was found to be comparable with that of infliximab, which is a commercially available anti-TNFα mAb.

Th17 Cells and the IL-23/IL-17 Axis in the Pathogenesis of Periodontitis and Immune-Mediated Inflammatory Diseases

Innate immunity represents the semi-specific first line of defense and provides the initial host response to tissue injury, trauma, and pathogens. Innate immunity activates the adaptive immunity, and both act highly regulated together to establish and maintain tissue homeostasis. Any dysregulation of this interaction can result in chronic inflammation and autoimmunity and is thought to be a major underlying cause in the initiation and progression of highly prevalent immune-mediated inflammatory diseases (IMIDs) such as psoriasis, rheumatoid arthritis, inflammatory bowel diseases among others, and periodontitis. Th1 and Th2 cells of the adaptive immune system are the major players in the pathogenesis of IMIDs. In addition, Th17 cells, their key cytokine IL-17, and IL-23 seem to play pivotal roles. This review aims to provide an overview of the current knowledge about the differentiation of Th17 cells and the role of the IL-17/IL-23 axis in the pathogenesis of IMIDs. Moreover, it aims to review the association of these IMIDs with periodontitis and briefly discusses the therapeutic potential of agents that modulate the IL-17/IL-23 axis.

A systematic review of the association of obesity with the outcomes of inflammatory rheumatic diseases

This was a systematic review of the literature on the association between obesity and the outcome of inflammatory rheumatic diseases. We conducted a literature search using PubMed®, Embase and PsycINFO®. Articles were classified into three categories based on the effects of obesity on the outcomes of inflammatory rheumatic diseases. The subject population, country, type of studies, number of patients, measurement of obesity and outcomes assessed were presented. Quality was appraised using Kmet et al's criteria. 4,331 articles were screened and 60 were relevant to the objective. Obesity had a negative, positive and neutral association with outcomes of inflammatory rheumatic diseases in 38 (63.3%) studies with 57,612 subjects, 11 (18.3%) studies with 3,866 subjects, and 11 (18.3%) studies with 3,834 subjects, respectively. In most studies, the disease population had been diagnosed with rheumatoid arthritis (RA). Tumour necrosis factor-α inhibitors were mostly associated with negative outcomes. More studies examining subjects outside Europe and North America and diseases other than RA are warranted.