Interleukin 10 treatment for rheumatoid arthritis

Delivery technologies for therapeutic targeting of fibronectin in autoimmunity and fibrosis applications

Fibronectin (FN) is a critical component of the extracellular matrix (ECM) contributing to various physiological processes, including tissue repair and immune response regulation. FN regulates various cellular functions such as adhesion, proliferation, migration, differentiation, and cytokine release. Alterations in FN expression, deposition, and molecular structure can profoundly impact its interaction with other ECM proteins, growth factors, cells, and associated signaling pathways, thus influencing the progress of diseases such as fibrosis and autoimmune disorders. Therefore, developing therapeutics that directly target FN or its interaction with cells and other ECM components can be an intriguing approach to address autoimmune and fibrosis pathogenesis.

Research Advances in Nucleic Acid Delivery System for Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that affects the lives of nearly 1% of the total population worldwide. With the understanding of RA, more and more therapeutic drugs have been developed. However, lots of them possess severe side effects, and gene therapy may be a potential method for RA treatment. A nanoparticle delivery system is vital for gene therapy, as it can keep the nucleic acids stable and enhance the efficiency of transfection in vivo. With the development of materials science, pharmaceutics and pathology, more novel nanomaterials and intelligent strategies are applied to better and safer gene therapy for RA. In this review, we first summarized the existing nanomaterials and active targeting ligands used for RA gene therapy. Then, we introduced various gene delivery systems for RA treatment, which may enlighten the relevant research in the future.

Magnoflorine attenuates inflammatory responses in RA by regulating the PI3K/Akt/NF-κB and Keap1-Nrf2/HO-1 signalling pathways in vivo and in vitro

BACKGROUND

As a prolonged autoimmune disorder, rheumatoid arthritis (RA) is characterised by synovial hyperplasia and the erosion of bone and cartilage. Magnoflorine (MAG) is the main component purified from Clematis manshurica Rupr. Recent studies have shown that MAG has anti-inflammatory, antioxidant, and immunosuppressive effects, which are relevant to anti-RA activities.

OBJECTIVE

The current investigation was conducted to explore the anti-RA effects of MAG and to discover the possible molecular mechanisms.

METHODS

In vitro experiments, CCK-8, wound healing, and transwell assays were utilized to evaluate the anti-proliferative, anti-migratory, and anti-invasive activities of MAG, respectively. The rate of cell distribution and cell apoptosis were evaluated by flow cytometry. ROS generation was detected by DCFH-DA staining. Western blotting, quantitative real-time polymerase chain reaction assay, and immunofluorescent staining were employed to test the anti-RA effect of MAG as well as to explore the potential mechanisms by evaluating related gene and protein expression. For in vivo experiments, an adjuvant-induced arthritis (AIA) rat model was established. The related parameters were measured in rats. Then, rats were sacrificed, and ankle joints were collected for histopathological analysis and observation.

RESULTS

MAG significantly decreased the proliferation, migration, invasion, and reactive oxygen species levels in IL-1β-treated MH7A cells. Furthermore, MAG promoted cell apoptosis by increasing Bax levels and decreasing Bcl-2 levels. MAG also induced cell cycle arrest. Inflammatory cytokines (iNOS, COX-2, IL-6, and IL-8) and MMPs (MMP-1, 2, 3, 9, and 13) were reduced by MAG treatment. Molecular analysis revealed that MAG exerted anti-RA effects by partly inhibiting the PI3K/Akt/NF-κB signalling axis and activating the Keap1-Nrf2/HO-1 signalling pathway. In vivo studies have revealed that MAG treatment substantially improved severe symptoms in AIA rats, and these curative effects were linked to the attenuation of inflammatory responses.

CONCLUSION

These results first suggested that MAG exhibits anti-arthritic effects in IL-1β-treated MH7A cells and AIA rat models. Thus, MAG may be used as a new drug to treat RA clinically.

IL-10 Induced by mTNF Crosslinking-Mediated Reverse Signaling in a Whole Blood Assay Is Predictive of Response to TNFi Therapy in Rheumatoid Arthritis

(1) Background: To date, the response of patients with rheumatoid arthritis (RA) to the various biologic DMARD available cannot be predicted due to a lack of reliable biomarkers. Based on our preliminary work on tmTNF reverse signaling, we developed a whole-blood assay measuring tmTNF crosslinking-induced IL-10 production to predict the response to TNF inhibitor (TNFi) therapy. (2) Methods: This prospective study included patients with active RA. Depending on the clinical judgment of the attending rheumatologist, either therapy with a TNF or JAK inhibitor was initiated. Clinical parameters and blood samples were obtained at baseline and after 8 weeks of therapy. The blood samples were collected using a newly developed whole-blood assay based on the principle of tmTNF reverse signalling. Subsequently, IL-10 was measured via enzyme-linked immunosorbent assay (ELISA) technique. (3) Results: 63 patients with RA were enrolled. In fifteen patients, TNFi therapy was initiated, while eight patients started a JAKi treatment. The cross-sectional analysis of all patients showed a positive correlation between tmTNF crosslinking-induced IL-10 and parameters of disease activity (CRP [r = 0.4091, p = 0.0009], DAS28 [r = 0.3303, p = 0.0082]) at baseline. In the TNFi treatment study, IL-10 was found to be significantly higher in EULAR responders than in non-responders (p = 0.0033). After initiation of JAKi treatment, in contrast, IL-10 induction was not linked to response. Longitudinal analysis of the TNFi-treated patients revealed IL-10 to decrease in responders (p = 0.04), but not in non-responders after 8 weeks of therapy. Of importance, the IL-10 production at baseline correlated inversely with TNFi response determined by ΔDAS28 in patients with TNFi treatment (r = −0.5299, p = 0.0422) while no such link was observed under JAKi therapy (p = 0.22). Receiver operation characteristics (ROC) analysis demonstrated a high performance of tmTNF/crosslinking-induced IL-10 in predicting a TNFi therapy response according to the EULAR criteria (AUC = 0.9286, 95% Confidence interval 0.7825–1.000, p = 0.0055). (4) Conclusions: In this pilot investigation, we demonstrated the feasibility of a whole-blood assay measuring tmTNF-induced IL-10 to predict clinical response to TNF inhibitor treatment. This approach might support rheumatologists in their decision for an individually tailored RA therapy.

A Preliminary Inquiry Into the Potential Mechanism of Huang-Lian-Jie-Du Decoction in Treating Rheumatoid Arthritis via Network Pharmacology and Molecular Docking

Huang-Lian-Jie-Du decoction (HLJDD) has been widely applied to treat inflammation-associated diseases for thousands of years in China. However, the concrete molecular mechanism of HLJDD in the treatment of rheumatoid arthritis (RA) remains unclear. In this work, network pharmacology and molecular docking were applied to preliminarily analyze the potential active ingredients, drug targets, and related pathways of HLJDD on treating RA. A total of 102 active compounds with corresponding 189 targets were identified from HLJDD, and 41 common targets were further identified by intersecting with RA-related targets. Functional enrichment analysis was performed to screen the biological pathways associated with RA. Ten hub targets were further identified through constructing the protein–protein interaction (PPI) network of common targets, which were mainly enriched in the interleukin-17 (IL-17) signaling pathway, tumor necrosis factor (TNF) signaling pathway, and Toll-like receptor signaling pathway. Furthermore, a complex botanical drugs-ingredients-hub-targets-disease network was successfully constructed. The molecular docking results exhibited that these vital ingredients of HLJDD had a stable binding to the hub targets. Among these ingredients, quercetin (MOL000098) was the most common molecule with stable binding to all the targets, and PTGS2 was considered the most important target with multiple regulations by the most active ingredients. In vitro, we successfully validated the inhibitory role of quercetin in the cellular proliferation of human RA fibroblast-like synoviocyte cell line (MH7A cells). These findings indicated that the potential mechanisms of HLJDD for RA treatment might be attributed to inhibiting the immune-inflammatory response, reducing the release of chemokines, and alleviating the destruction of extracellular matrix (ECM) in the synovial compartment.

Transcriptional and Histochemical Signatures of Bone Marrow Mononuclear Cell-Mediated Resolution of Synovitis

Osteoarthritis (OA) may result from impaired ability of synovial macrophages to resolve joint inflammation. Increasing macrophage counts in inflamed joints through injection with bone marrow mononuclear cells (BMNC) induces lasting resolution of synovial inflammation. To uncover mechanisms by which BMNC may affect resolution, in this study, differential transcriptional signatures of BMNC in response to normal (SF) and inflamed synovial fluid (ISF) were analyzed. We demonstrate the temporal behavior of co-expressed gene networks associated with traits from related in vivo and in vitro studies. We also identified activated and inhibited signaling pathways and upstream regulators, further determining their protein expression in the synovium of inflamed joints treated with BMNC or DPBS controls. BMNC responded to ISF with an early pro-inflammatory response characterized by a short spike in the expression of a NF-ƙB- and mitogen-related gene network. This response was associated with sustained increased expression of two gene networks comprising known drivers of resolution (IL-10, IGF-1, PPARG, isoprenoid biosynthesis). These networks were common to SF and ISF, but more highly expressed in ISF. Most highly activated pathways in ISF included the mevalonate pathway and PPAR-γ signaling, with pro-resolving functional annotations that improve mitochondrial metabolism and deactivate NF-ƙB signaling. Lower expression of mevalonate kinase and phospho-PPARγ in synovium from inflamed joints treated with BMNC, and equivalent IL-1β staining between BMNC- and DPBS-treated joints, associates with accomplished resolution in BMNC-treated joints and emphasize the intricate balance of pro- and anti-inflammatory mechanisms required for resolution. Combined, our data suggest that BMNC-mediated resolution is characterized by constitutively expressed homeostatic mechanisms, whose expression are enhanced following inflammatory stimulus. These mechanisms translate into macrophage proliferation optimizing their capacity to counteract inflammatory damage and improving their general and mitochondrial metabolism to endure oxidative stress while driving tissue repair. Such effect is largely achieved through the synthesis of several lipids that mediate recovery of homeostasis. Our study reveals candidate mechanisms by which BMNC provide lasting improvement in patients with OA and suggests further investigation on the effects of PPAR-γ signaling enhancement for the treatment of arthritic conditions.

Bone marrow mononuclear cells for joint therapy: The role of macrophages in inflammation resolution and tissue repair

Osteoarthritis (OA) is the most prevalent joint disease causing major disability and medical expenditures. Synovitis is a central feature of OA and is primarily driven by macrophages. Synovial macrophages not only drive inflammation but also its resolution, through a coordinated, simultaneous expression of pro- and anti-inflammatory mechanisms that are essential to counteract damage and recover homeostasis. Current OA therapies are largely based on anti-inflammatory principles and therefore block pro-inflammatory mechanisms such as prostaglandin E₂ and Nuclear factor-kappa B signaling pathways. However, such mechanisms are also innately required for mounting a pro-resolving response, and their blockage often results in chronic low-grade inflammation. Following minor injury, macrophages shield the damaged area and drive tissue repair. If the damage is more extensive, macrophages incite inflammation recruiting more macrophages from the bone marrow to maximize tissue repair and ultimately resolve inflammation. However, sustained damage and inflammation often overwhelms pro-resolving mechanisms of synovial macrophages leading to the chronic inflammation and related tissue degeneration observed in OA. Recently, experimental and clinical studies have shown that joint injection with autologous bone marrow mononuclear cells replenishes inflamed joints with macrophage and hematopoietic progenitors, enhancing mechanisms of inflammation resolution, providing remarkable and long-lasting effects. Besides creating an ideal environment for resolution with high concentrations of interleukin-10 and anabolic growth factors, macrophage progenitors also have a direct role in tissue repair. Macrophages constitute a large part of the early granulation tissue, and further transdifferentiate from myeloid into a mesenchymal phenotype. These cells, characterized as fibrocytes, are essential for repairing osteochondral defects. Ongoing “omics” studies focused on identifying key drivers of macrophage-mediated resolution of joint inflammation and those required for efficient osteochondral repair, have the potential to uncover ways for developing engineered macrophages or off-the-shelf pro-resolving therapies that can benefit patients suffering from many types of arthropaties, not only OA.

BT2 Suppresses Human Monocytic-Endothelial Cell Adhesion, Bone Erosion and Inflammation

Introduction

Inflammation and bone erosion are processes key to the pathogenesis of rheumatoid arthritis, a systemic autoimmune disease causing progressive disability and pain, impacting around 1.3 million people in the United States alone. However, many patients do not respond sufficiently to existing therapies or benefit is not sustained and alternate therapeutic approaches are lacking. We recently identified the dibenzoxazepinone BT2, which inhibits ERK phosphorylation, from a high-throughput chemical screen and identified its ability to inhibit angiogenesis and vascular leakiness.

Methods

Here we evaluated BT2 for potential anti-inflammatory activity in in vitro models of human monocytic-endothelial cell adhesion, monocytic cell extravasation and collagen antibody-induced arthritis in mice.

Results

BT2 inhibits human monocytic cell adhesion to IL-1ß-treated human endothelial cells and inhibits monocytic transendothelial migration toward MCP-1. In mice rendered arthritic, single systemic administration of BT2 prevented footpad swelling, bone destruction and TRAP⁺ cells in the joints. BT2 suppressed inducible circulating levels of IL-1ß, IL-2 and IL-6 to normal levels without affecting levels of IL-4 or IL-10 among other cytokines. BT2 also inhibited the expression of pro-inflammatory adhesion molecules ICAM-1 and VCAM-1 in arthritic joints. There was no evidence of toxicity following intraperitoneal, gavage or intraarticular administration of BT2.

Conclusion

BT2 is a novel small molecule inhibitor of joint inflammation, bone erosion, pro-inflammatory cytokine and adhesion molecule expression. This suggests the potential clinical utility of BT2 as a new anti-inflammatory agent.

Macrophage Activation in the Synovium of Healthy and Osteoarthritic Equine Joints

Synovitis is a major component of osteoarthritis and is driven primarily by macrophages. Synovial macrophages are crucial for joint homeostasis (M2-like phenotype), but induce inflammation (M1-like) when regulatory functions become overwhelmed. Macrophage phenotypes in synovium from osteoarthritic and healthy joints are poorly characterized; however, comparative knowledge of their phenotypes during health and disease is paramount for developing targeted treatments. This study compared patterns of macrophage activation in healthy and osteoarthritic equine synovium and correlated histology with cytokine/chemokine profiles in synovial fluid. Synovial histology and immunohistochemistry for M1-like (CD86), M2-like (CD206, IL-10), and pan macrophage (CD14) markers were performed on biopsies from 29 healthy and 26 osteoarthritic equine joints. Synovial fluid cytokines (MCP-1, IL-10, PGE2, IL-1β, IL-6, TNF-α, IL-1ra) and growth factors (GM-CSF, SDF-1α+β, IGF-1, and FGF-2) were quantified. Macrophage phenotypes were not as clearly defined in vivo as they are in vitro. All macrophage markers were expressed with minimal differences between OA and normal joints. Expression for all markers increased proportionate to synovial inflammation, especially CD86. Synovial fluid MCP-1 was higher in osteoarthritic joints while SDF-1 and IL-10 were lower, and PGE2 concentrations did not differ between groups. Increased CD14/CD86/CD206/IL-10 expression was associated with synovial hyperplasia, consistent with macrophage recruitment and activation in response to injury. Lower synovial fluid IL-10 could suggest that homeostatic mechanisms from synovial macrophages became overwhelmed preventing inflammation resolution, resulting in chronic inflammation and OA. Further investigations into mechanisms of arthritis resolution are warranted. Developing pro-resolving therapies may provide superior results in the treatment of OA.

Anti-inflammatory and immune-regulatory cytokines in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by a failure of spontaneous resolution of inflammation. Although the pro-inflammatory cytokines and mediators that trigger RA have been the focus of intense investigations, the regulatory and anti-inflammatory cytokines responsible for the suppression and resolution of disease in a context-dependent manner have been less well characterized. However, knowledge of the pathways that control the suppression and resolution of inflammation in RA is clinically relevant and conceptually important for understanding the pathophysiology of the disease and for the development of treatments that enable long-term remission. Cytokine-mediated processes such as the activation of T helper 2 cells by IL-4 and IL-13, the resolution of inflammation by IL-9, IL-5-induced eosinophil expansion, IL-33-mediated macrophage polarization, the production of IL-10 by regulatory B cells and IL-27-mediated suppression of lymphoid follicle formation are all involved in governing the regulation and resolution of inflammation in RA. By better understanding these immune-regulatory signalling pathways, new therapeutic strategies for RA can be envisioned that aim to balance and resolve, rather than suppress, inflammation.

Inflamed synovial fluid induces a homeostatic response in bone marrow mononuclear cells in vitro: Implications for joint therapy

Synovial inflammation is a central feature of osteoarthritis (OA), elicited when local regulatory macrophages (M2-like) become overwhelmed, activating an inflammatory response (M1-like). Bone marrow mononuclear cells (BMNC) are a source of naïve macrophages capable of reducing joint inflammation and producing molecules essential for cartilage metabolism. This study investigated the response of BMNC to normal (SF) and inflamed synovial fluid (ISF). Equine BMNC cultured in autologous SF or ISF (n = 8 horses) developed into macrophage-rich cultures with phenotypes similar to cells native to normal SF and became more confluent in ISF (~100%) than SF (~25%). BMNC cultured in SF or ISF were neither M1- nor M2-like, but exhibited aspects of both phenotypes and a regulatory immune response, characterized by increasing counts of IL-10⁺ macrophages, decreasing IL-1β concentrations and progressively increasing IL-10 and IGF-1 concentrations. Changes were more marked in ISF and suggest that homeostatic mechanisms were preserved over time and were potentially favored by progressive cell proliferation. Collectively, our data suggest that intra-articular BMNC could increase synovial macrophage counts, potentiating the macrophage- and IL-10-associated mechanisms of joint homeostasis lost during the progression of OA, preserving the production of cytokines involved in tissue repair (PGE₂ , IL-10) generally impaired by frequently used corticosteroids.

Regulatory T Cell Suppressive Activity Predicts Disease Relapse During Disease-Modifying Anti-rheumatic Drug Dose Reduction in Rheumatoid Arthritis: A Prospective Cohort Study

When the dose of conventional disease-modifying anti-rheumatic drugs (cDMARDs) is tapered in rheumatoid arthritis (RA) patients who achieve sustained remission, biomarkers for predicting disease relapse may be needed. A prospective, unblinded cohort study was conducted in nine RA patients with remission. Peripheral blood samples were collected at baseline and at 6, 12, and 24 weeks after cDMARD dose reduction (dose of combination regimens reduced to 50%) to determine the number of regulatory Foxp3⁺T cells (Tregs) and other T cell subpopulations as well as Treg suppressive activity. Additionally, plasma levels of 14 cytokines at each time-point were measured via flow cytometry. Univariate and multivariate analyses were performed to identify the factor(s) associated with RA relapse during the observational period. In univariate analysis, Treg suppression and DAS28 and VAS scores were associated with RA relapse after cDMARD dose tapering. However, in multivariate analysis, only Treg suppressive activity (<42%) was found to be an independent factor associated with RA relapse after cDMARD dose reduction to 50%. Of all patients who had ≥42% Treg suppressive activity during cDMAD reduction, three-fourth patients remained in the remission stage for 24 weeks. Treg suppressive activity (<42%) in RA patients with remission could be a potential biomarker for predicting RA relapse after cDMARD dose reduction, especially over a short-term period (24 weeks).

Autologous bone marrow mononuclear cells modulate joint homeostasis in an equine in vivo model of synovitis

Osteoarthritis (OA) is characterized by macrophage-driven synovitis. Macrophages promote synovial health but become inflammatory when their regulatory functions are overwhelmed. Bone marrow mononuclear cells (BMNCs) are a rich source of macrophage progenitors used for treating chronic inflammation and produce essential molecules for cartilage metabolism. This study investigated the response to autologous BMNC injection in normal and inflamed joints. Synovitis was induced in both radiocarpal joints of 6 horses. After 8 h, 1 inflamed radiocarpal and 1 normal tarsocrural joint received BMNC injection. Contralateral joints were injected with saline. Synovial fluid was collected at 24, 96, and 144 h for cytology, cytokine quantification, and flow cytometry. At 144 h, horses were euthanatized, joints were evaluated, and synovium was harvested for histology and immunohistochemistry. Four days after BMNC treatment, inflamed joints had 24% higher macrophage counts with 10% more IL-10⁺ cells than saline-treated controls. BMNC-treated joints showed gross and analytical improvements in synovial fluid and synovial membrane, with increasing regulatory macrophages and synovial fluid IL-10 concentrations compared with saline-treated controls. BMNC-treated joints were comparable to healthy joints histologically, which remained abnormal in saline-treated controls. Autologous BMNCs are readily available, regulate synovitis through macrophage-associated effects, and can benefit thousands of patients with OA.-Menarim, B. C., Gillis, K. H., Oliver, A., Mason, C., Ngo, Y., Werre, S. R., Barrett, S. H., Luo, X., Byron, C. R., Dahlgren, L. A. Autologous bone marrow mononuclear cells modulate joint homeostasis in an equine in vivo model of synovitis.

Treatment of Type II Collagen-Induced Rat Rheumatoid Arthritis Model by Interleukin 10 (IL10)-Mesenchymal Stem Cells (BMSCs)

BACKGROUND Rheumatoid arthritis model (CIA) rats were treated by tail vein injection of IL-10-modified bone marrow mesenchymal stem cells (BMSCs) to investigate its feasibility and intrinsic molecular mechanism. MATERIAL AND METHODS The CIA rat model was established by induction type II collagen, and IL-10-modified BMSCs was established by transfecting BMSCs with adenovirus. IL-10-modified BMSCs were used to treat the CIA rats. The therapeutic effect was evaluated by measuring the changes in body weight, ankle swelling, and forced swimming time, as well as observation of synovial hyperplasia and cartilage tissue repair by HE staining. Western blot analysis and ELISA were used to detect gene expression. RESULTS After 4 weeks and 8 weeks of treatment with IL10-BMSCs, the body weight, swelling value, resting time, and forced swimming struggle time of CIA rats were significantly higher than those of BMSCs-treated and -untreated CIA rats (P<0.05). Compared to BMSCs-treated CIA model rats, after treatment with IL10-BMSCs, the repair rate of osteoarticular cartilage was higher and the inhibition of synovial proliferation was better, and serum IL-17, IL-1ß, and TNF-alpha levels were lower. We found that the protein level of SIRT1 in peripheral blood mononuclear cells was lower, the protein level in spleen was higher, and phosphorylation of p65 protein in peripheral blood mononuclear cells was reduced. CONCLUSIONS The efficacy of tail vein injection of IL-10-modified BMSCs in treatment of CIA rats was superior to that of BMSCs alone, which may be related to the more pronounced suppression of IL-10-modified BMSCs in peripheral blood inflammation and spleen immune response.

3,5-Di-C-β-D-glucopyranosyl phloroacetophenone, a major component of Melicope ptelefolia, suppresses fibroblast activation and alleviates arthritis in a mouse model: Potential therapeutics for rheumatoid arthritis

Melicope ptelefolia has been traditionally used to treat rheumatism and fever. The present study aimed to investigate the therapeutic effect of 3,5-di-C-β-_d-glucopyranosyl phloroacetophenone (βGP), a main component of M. ptelefolia, on rheumatoid arthritis (RA). A model of collagen-induced arthritis (CIA) was established in mice using the RAW 264.7 murine macrophage cell line and mouse embryonic fibroblasts (MEFs). The clinical scores of arthritis, swelling, histopathological findings, and micro-computed tomography in CIA mouse paws were assessed. The levels of anti-type II collagen antibody and cytokines were determined in the plasma and cell culture supernatant, respectively. Protein and gene expression levels were analyzed by western blot and reverse transcription-quantitative polymerase chain reaction analyses. βGP significantly decreased the gross arthritic scores of CIA mice and joint swelling, and decreased articular inflammation, cartilage degradation and bone erosion. However, βGP did not exert any effect on anti-type II collagen immunoglobulin G plasma levels or inflammatory cytokine expression in macrophages. βGP significantly suppressed the expression of interleukin-6 and leukemia inhibitory factor and decreased the phosphorylation of signal transducer and activator of transcription 3, and expression of receptor activator of nuclear factor-κB ligand in tumor necrosis factor-α-stimulated MEFs and in CIA mouse paws. Osteoclast-related gene expression was significantly reduced in CIA mouse paws. Taken together, βGP suppressed the development of RA by regulating the activation of synovial fibroblasts.

Human Leukocyte Antigen Shared Epitope and Inflammation, Cardiovascular Disease, Cancer, and Mortality Among Postmenopausal Women in the Women's Health Initiative Rheumatoid Arthritis Study

Specific alleles of the human leukocyte antigen (HLA)-DRB1 gene (HLA-DRB1) encode a "shared epitope" (SE) associated with rheumatoid arthritis (RA), especially more severe cyclic-citrullinated peptide antibody-positive (anti-CCP+) RA. We evaluated associations of number of SE alleles (0, 1, or 2) with total and cardiovascular disease (CVD) mortality and incident coronary heart disease (CHD), CVD, and cancer over a mean 8.9 (standard deviation, 3.5) years of follow-up, stratifying by baseline anti-CCP status (positive (+) vs. negative (-)). A longitudinal study, the Women's Health Initiative RA Study (1993-2010), sampled postmenopausal women who reported RA at baseline (1993-1998) or follow-up in the Women's Health Initiative, classified as anti-CCP+ RA (n = 556) or anti-CCP- non-RA (n = 1,070). Among anti-CCP+ RA women, SE alleles were not related to age-adjusted risks of CHD, CVD, or cancer or to total or CVD mortality. Among anti-CCP- non-RA women, age-adjusted hazard ratios for 1 and 2 SE alleles versus 0 SE alleles were 0.41 (95% confidence interval (CI): 0.34, 0.50) and 0.44 (95% CI: 0.27, 0.72), respectively, for CVD; 0.43 (95% CI: 0.37, 0.53) and 0.30 (95% CI: 0.16, 0.64), respectively, for CHD; and 0.62 (95% CI: 0.53, 0.73) and 0.52 (95% CI: 0.33, 0.83), respectively, for cancer. Associations persisted after adjustment for CVD risk factors, joint pain, rheumatoid factor positivity, and inflammatory markers (white blood cell count or cytokine level). In future studies, investigators should evaluate SE associations among anti-CCP- adults without RA and potential mechanisms.

Discovery of New Benzothiazine Derivative as Modulator of Pro- and Anti-inflammatory Cytokines in Rheumatoid Arthritis

The anti-inflammatory activities of benzothiazine and pyrazole derivatives are well documented. A series of novel N'-arylmethylidene-2-(3,4-dimethyl-5,5-dioxidopyrazolo(4,3 c)(1,2) benzothiazin-2(4H)yl) acetohydrazide compounds were previously synthesized by combining benzothiazine and pyrazole moieties into a single nucleus. The current study investigates the anti-arthritic potential of 3-ethoxy-4-hydroxyphenyl derivative (EHP) and its possible mechanism in arthritic rat model. Sprague-Dawley rats were induced rheumatoid arthritis with Freund's complete adjuvant and treated with EHP and piroxicam. At the end of the study, arthritic score was calculated, and ankle joint histopathology was performed using hematoxylin and eosin staining. Real-time reverse transcription polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) were used to determine mRNA expression and protein levels of various inflammatory markers, respectively. In vitro concanavalin A (ConA)-stimulated splenocyte proliferation was measured. Serum levels of C-reactive protein (CRP), urea, creatinine, aspartate aminotransferase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP) were also determined. EHP significantly attenuated macroscopic arthritic score, joint histopathological lesions, and CRP levels. Treatment with EHP significantly reduced pro-inflammatory tissue necrosis factor-α (TNF-α), nuclear factor-kappa B (NF-кB), interleukin-17 (IL-17), and prostaglandin-E2 (PGE2) levels and increased the levels of anti-inflammatory interleukin-4 (IL-4) and interleukin-10 (IL-10). ConA-stimulated splenocyte proliferation was also significantly suppressed by treatment with EHP. Normalizing all hematological markers and ALP levels, EHP did not display any sign of nephrotoxicity and hepatotoxicity as determined by urea, creatinine, ALT, and AST levels. In conclusion, EHP possesses significant anti-arthritic property which may be attributed to its anti-inflammatory and immunomodulatory effects.

Role of LncRNA-AF085935, IL-10 and IL-17 in Rheumatoid Arthritis Patients With Chronic Hepatitis C

BACKGROUND

The current study aimed at testing the effect of corticosteroid therapy on serum levels of interleukin-10 (IL-10) and IL-17 as well as lncRNA-AF085935 in patients of rheumatoid arthritis (RA) associated with hepatitis C virus (HCV) and evaluating the usefulness of using these parameters to predict the therapeutic efficacy of steroids in these patients.

METHODS

Thirty healthy control subjects and 65 chronic HCV patients with RA were included in our study. Patients were subjected to clinical examination, abdominal ultrasound, and liver biopsy and received 6-methyl-prednisolone (PDN) 16 mg/day for 48 weeks. Blood samples were collected from all subjects and serum was separated to assess IL-10 and IL-17 by ELISA and HCV RNA and lncRNA-AF085935 by qRT-PCR.

RESULTS

Our study revealed that there were significant increases in serum levels of IL-10, IL-17 and lncRNA-AF085935 in RA patients associated with HCV compared with healthy control subjects. Also there were significant increases in serum levels of IL-10 and HCV RNA and a significant decrease in serum level of IL-17 in patients after corticosteroid therapy, while lncRNA-AF085935 is not significantly changed.

CONCLUSION

LncRNA-AF085935 might be a useful candidate biomarker for the early detection of RA associated with HCV, providing potential new strategies for early screening and therapy of these patients. IL-17 is a non-invasive prognostic marker to predict the efficacy of corticosteroid therapy in RA patients associated with chronic hepatitis C.

Extract from Eucommia ulmoides Oliv. ameliorates arthritis via regulation of inflammation, synoviocyte proliferation and osteoclastogenesis in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Eucommia ulmoides Oliv., a valuable Chinese herb, has shown a variety of health benefits. Despite the widespread clinical use of this herb to treat rheumatoid arthritis (RA) in Traditional Chinese Medicine (TCM), very few studies have described its anti-pathological effects or mechanism in RA. The present study investigated the mechanism of Eucommia ulmoides Oliv. in an experimental collagen-induced arthritis (CIA) rat model.

MATERIALS AND METHODS

The effects of four different Eucommia ulmoides Oliv. extracts on the proliferation of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) were screened in an MTT assay, and apoptotic effects were detected by flow cytometry. Among the extracts, the 70% ethanol extract (EU70) presented the best inhibition and was further investigated for its curative effect in CIA rats. Foot swelling was detected, and the arthritis index (AI) was scored. Pathological improvement was assessed by haematoxylin and eosin (H&E) staining of joint tissues. The mechanistic effects of EU70 were investigated as follows: anti-inflammatory effects in Th17-positive cells by flow cytometry; serum levels of inflammatory cytokines by ELISA; TNFα and IL-1β expression by immunohistochemistry (IHC); and anti-osteoclastogenesis by QPCR detection of RANKL and OPG mRNA.

RESULTS

Compared with vehicle treatment in CIA model rats, EU70 significantly ameliorated foot swelling, decreased AI in vivo and reduced inflammatory cell infiltration and synoviocyte proliferation. EU70 decreased the number of Th17-positive cells in the spleen and the serum levels of cytokines, including IL-17, IL-1β and TNFα, and upregulated the serum levels of IL-10; these results indicated the anti-inflammatory effect of EU70. Moreover, EU70 effectively suppressed TNFα and IL-1β expression in the joint tissues and resulted in the downregulation of RANKL mRNA and the upregulation of OPG mRNA. These results revealed the possible preventive role of EU70 against bone destruction.

CONCLUSION

For the first time, these mechanisms and pathological improvements support the clinical use of Eucommia ulmoides Oliv. in treating RA. The findings indicated that the 70% ethanol extract of Eucommia ulmoides Oliv. could relieve RA symptoms by (1) suppressing the proliferation of synoviocytes, (2) reducing the number of Th17-positive cells and downregulating serum IL-17 expression, (3) increasing the anti-inflammatory effects of IL-10, (4) inhibiting the serum and tissue levels of key pro-inflammatory cytokines, TNFα and IL-1β, and (5) reducing the degradation of cartilage and bone.

Pathologic patterns of interleukin 10 expression--a review

Interleukin 10 (IL-10) is important pleiotropic immunoregulatory cytokine which gene is located on chromosome 1 at 1q31-32. There are many genetic variants of IL-10 gene. However, the most studied are two dinucleotide repeats (microsatellites), IL10.G and IL10.R, located 1.2 kb and 4 kb upstream of the transcription start site and three single nucleotide polymorphisms (SNPs) -1082(G/A), -819(C/T) and -592(C/A). A large number of studies have shown that IL-10 gene polymorphisms are associated with different diseases and play an important role in pathophysiology and clinical course of these diseases. This review summarizes published literature knowledge about the association of IL-10 polymorphisms and expression patterns with asthma, systemic lupus erythematosus, psoriasis, inflammatory bowel disease, rheumatoid arthritis, tuberculosis and some neoplasms.

Inflammatory markers in patients with rheumatoid arthritis

BACKGROUND

Autoimmune diseases such as rheumatoid arthritis (RA) are the consequence of a persistent imbalance between pro- and anti-inflammatory immune mechanisms, leading to chronic inflammation. The objective of this study was to determine whether the high sensitive C-reactive protein (hs-CRP) and cytokines are elevated in RA patients and to investigate the relationship between these markers and disease activity in RA, measured by disease activity score 28 (DAS28).

METHODS

We studied 110 RA patients according to American College of Rheumatology revised criteria for RA, and 55 controls matched by age and sex. Serum levels of hs-CRP and cytokines interleukin (IL)-6, IL-10 and tumour necrosis factor-α (TNF-α) were estimated and correlated with the DAS28. Serum hs-CRP was assayed immunoturbidimetrically and cytokines were analysed by commercially available ELISA kit.

RESULTS

We found that RA patients had significantly higher levels of serum hs-CRP (p<0.001), IL-6 (p<0.001), TNF-α (p<0.001), and IL-10 (p<0.01) as compared to healthy controls. hs-CRP, IL-6 and TNF-α correlated positively (p<0.001) and IL-10 correlated negatively (p<0.01) with DAS28.

CONCLUSIONS

These results demonstrate that RA patients have high levels of inflammatory markers, and these levels are correlated with the DAS28. These findings suggest a possible role of these markers in the pathogenesis of RA. Moreover, these biomarkers can be used as markers of disease activity in the diagnosis and treatment of RA.

Blood B Cell and Regulatory Subset Content in Multiple Sclerosis Patients

OBJECTIVE

B cell targeted therapies have been effective in slowing multiple sclerosis (MS) disease progression suggesting a direct causal link for this lymphoid subset. A small subset of B cells with regulative properties (Bregs) exists in peripheral blood, and induction of Bregs ameliorates experimental autoimmune encephalomyelitis (EAE), the murine model for MS. Therefore the frequency of B cell subsets and regulatory B cells in particular in peripheral blood of MS patients is of interest.

METHODS

The phenotype and frequency of B cell subsets in peripheral blood from 32 MS patients and 34 healthy controls (HC) were examined using flow cytometry.

RESULTS

We found that there is an increase in CD19⁺ cell number in MS 1347 ± 159 cells/μL, (average ± SEM) compared to HC, 935 ± 129 cells/μL and no apparent deficiency in B-cells with a regulatory phenotype. In addition, we observed a loss of correlation between CD19⁺ B cells and total lymphocyte count in MS.

CONCLUSION

These findings suggest altered blood B-cell homeostasis in MS patients.

Replacements of rare herbs and simplifications of traditional chinese medicine formulae based on attribute similarities and pathway enrichment analysis

A Traditional Chinese Medicine (TCM) formula is a collection of several herbs. TCM formulae have been used to treat various diseases for several thousand years. However, wide usage of TCM formulae has results in rapid decline of some rare herbs. So it is urgent to find common available replacements for those rare herbs with the similar effects. In addition, a formula can be simplified by reducing herbs with unchanged effects. Based on this consideration, we propose a method, called "formula pair," to replace the rare herbs and simplify TCM formulae. We show its reasonableness from a perspective of pathway enrichment analysis. Both the replacements of rare herbs and simplifications of formulae provide new approaches for a new formula discovery. We demonstrate our approach by replacing a rare herb "Forsythia suspensa" in the formula "the seventh of Sang Ju Yin plus/minus herbs (SSJY)" with a common herb "Thunberg Fritillary Bulb" and simplifying two formulae, "the fifth of Du Huo Ji Sheng Tang plus/minus herbs (FDHJST)" and "Fang Feng Tang" (FFT) to a new formula "Fang Feng Du Huo Tang" (FFDHT).

Interleukin-10 inhibits the in vivo and in vitro adverse effects of TNF-alpha on the endothelium of murine aorta

TNF-α is a proinflammatory cytokine and is an important mediator of maternal endothelial dysfunction leading to preeclampsia. In this study, we tested whether IL-10 protects against TNF-α-induced endothelial dysfunction in murine aorta. In in vitro experiments, aortic rings of C57BL/6 female mice were incubated in Dulbecco's modified Eagle's medium in the presence of either vehicle (distilled H(2)O), TNF-α (4 nmol/l), or recombinant mouse IL-10 (300 ng/ml) or in the presence of both TNF-α and IL-10 for 22 h at 37°C. In in vivo experiments C57BL6/IL-10 knockout female mice were treated with saline or TNF-α (220 ng·kg(-1)·day(-1)) for 14 days. Aortic rings were isolated from in vitro and in vivo experiments and mounted in a wire myograph (Danish Myotech) and stretched to a tension of 5 mN. Endothelium-dependent relaxation was assessed by constructing cumulative concentration-response curves to acetylcholine (ACh, 0.001-10 μmol/l) during phenylephrine (10 μmol/l)-induced contraction. As a result, overnight exposure of aortic rings to TNF-α resulted in significant blunted maximal relaxing responses (E(max)) to ACh compared with untreated rings (22 ± 4 vs. 82 ± 3%, respectively). IL-10 knockout mice treated with TNF-α showed significant impairment in ACh responses (E(max)) compared with C57BL/6 mice treated with TNF-α (51 ± 3 vs. 72 ± 3%, respectively). Western blot analysis showed that endothelial nitric oxide synthase (eNOS) expression was reduced by TNF-α in in vitro and in vivo experiments, whereas IL-10 restored the eNOS expression. In conclusion, the anti-inflammatory cytokine IL-10 prevents impairment in endothelium-dependent vasorelaxation caused by TNF-α by protecting eNOS expression.

Lactobacillus casei suppresses experimental arthritis by down-regulating T helper 1 effector functions

Although the beneficial effects of probiotics on wide variety of diseases have been shown, little is known about how probiotics modulate the immune system. In this study we elucidated the underlying mechanisms how Lactobacillus casei (L. casei) protects against rheumatoid arthritis (RA) progression by investigating the effector functions of CD4(+) T cells. Oral administration of L. casei suppressed collagen-induced arthritis (CIA) and reduced paw swelling, lymphocyte infiltration and destruction of cartilage tissue. L. casei administration reduced type II collagen (CII)-reactive proinflammatory molecules (IL-1beta, IL-2, IL-6, IL-12, IL-17, IFN-gamma, TNF-alpha and Cox-2) by CD4(+) T cells. L. casei administration also reduced translocation of NF-kappaB into nucleus and CII-reactive Th1-type IgG isotypes IgG2a and IgG2b, while up-regulating immunoregulatory IL-10 levels. Our results suggest that oral administration of L. casei suppresses the type II collagen-reactive effector function of Th1-type cellular and humoral immune responses in arthritic inflammation.

Dexamethasone or interleukin-10 blocks interleukin-1beta-induced uterine contractions in pregnant rhesus monkeys

OBJECTIVE

The purpose of this study was to determine whether treatment with the immune modulators dexamethasone or interleukin-10 prevents interleukin-1beta-induced uterine contractions in a nonhuman primate model.

STUDY DESIGN

Thirteen chronically instrumented rhesus monkeys at 135 +/- 1 days of gestation (term, 167 days) received one of three interventions: (1) intra-amniotic interleukin-1beta (10 microg) infusion with maternal dexamethasone (1 mg/kg) intravenously every 6 hours for 1 day before interleukin-1beta and for 2 days thereafter (n = 4), (2) intra-amniotic interleukin-1beta infusion with maternal interleukin-10 (25 microg/kg) given intravenously and 100 microg interleukin-10 given intra-amniotically before the interleukin-1beta and continued every 8 hours for 3 days (n = 5), and (3) intra-amniotic interleukin-1beta administered alone (n = 5). Uterine activity was monitored continuously and quantified as the hourly contraction area (millimeters of mercury times seconds per hour) in all groups until delivery. Amniotic fluid was sampled for leukocyte counts and assayed for prostaglandins E(2) and F(2)alpha, cytokines interleukin-1beta, interleukin-6, interleukin-8, tumor necrosis factor-alpha, interleukin-10, and interleukin-1 receptor antagonist by specific assays. Maternal and fetal blood were assayed for cortisol, dehydroepiandrosterone sulfate, and estradiol.

RESULTS

Interleukin-1beta infusion in the absence of immune modulators resulted in an increase in uterine activity and amniotic fluid proinflammatory cytokines, prostaglandins, and leukocytes. Dexamethasone and interleukin-10 treatment significantly reduced interleukin-1beta-induced uterine contractility (P <.05) and amniotic fluid prostaglandins (P <.05) but not interleukin-8 or interleukin-1 receptor antagonist. Amniotic fluid interleukin-6 and maternal and fetal cortisol, dehydroepiandrosterone sulfate, and estradiol concentrations were reduced by dexamethasone (P <.05), whereas tumor necrosis factor-alpha levels and leukocyte counts were attenuated by interleukin-10 treatment (P <.05). An inverse relationship was noted between amniotic fluid interleukin-10 concentrations and interleukin-1beta-induced uterine activity (r = -0.74, P <.05).

CONCLUSION

Dexamethasone and interleukin-10 exert similar inhibitory effects on interleukin-1beta-induced uterine activity, which appears to be mediated by a decrease in prostaglandin production. Reduced estrogen biosynthesis or suppression of tumor necrosis factor-alpha and leukocyte migration may contribute to the tocolytic actions of dexamethasone and interleukin-10, respectively. Dexamethasone and interleukin-10 are likely to be useful adjuncts in the treatment of preterm labor that is associated with inflammation or infection.

mRNA expression of cytokines and chemokines in herniated lumbar intervertebral discs

STUDY DESIGN

The mRNA expressions of cytokines and chemokines were assessed in herniated lumbar disc specimens.

OBJECTIVES

To investigate whether the mRNAs of interleukin (IL)-1alpha, tumor necrosis factor (TNF)-alpha, RANTES, IL-8, IL-10, and transforming growth factor (TGF)-beta are expressed in surgically obtained herniated disc specimens; and to discover which of them are the predominant cytokines associated with the clinical symptoms and signs, and whether any differences in the mRNA expression exist depending on the different types of disc herniations.

SUMMARY OF BACKGROUND DATA

It has been postulated that cytokines are involved in causing radicular leg pain in lumbar disc herniations. Although a few studies have been done on lumbar disc herniations concerning IL-1alpha and TNF-alpha, almost none has been carried out in the cases of the other of cytokines and chemokines.

METHODS

Using a reverse transcription-polymerase chain reaction, mRNA expressions of cytokines and chemokines were investigated in herniated disc specimens. The straight leg raising test, development of radicular pain by back extension, symptom duration, pain intensity using a visual analogue scale, and herniation types were described.

RESULTS

The mRNAs of IL-8, TNF-alpha, IL-1alpha, RANTES, and IL-10 were expressed in 16 (70%), 15 (65%), 9 (39%), 4 (17%), and 2 (9%) of the 23 herniated disc specimens, respectively. The mRNA of TGF-beta was expressed in 5 of 10 specimens (50%). IL-8 mRNA expression was associated with the development of radicular pain by back extension and short symptom duration (average 3.8 weeks). The mRNAs of IL-1alpha were expressed more frequently in transligamentous extensions than in subligamentous extensions, but the expression was weak.

CONCLUSION

Interleukin-8 appears to be associated with development of radicular pain by back extension and to be activated on acute or subacute disc herniations. IL-8 seems to participate in the pathomechanism of nerve root inflammation in lumbar disc herniations, which implies that it may be considered a target for therapeutic intervention.

IL-10 improves skin disease and modulates endothelial activation and leukocyte effector function in patients with psoriatic arthritis

Psoriatic arthritis (PsA) provides an ideal disease model in which to investigate the bioactivities of potentially therapeutic cytokines at multiple sites of tissue inflammation. We investigated the effects of IL-10, an antiinflammatory cytokine, given s.c. for 28 days in a double-blind, placebo-controlled study in PsA patients. Synovial/skin biopsies, peripheral blood leukocytes, articular magnetic resonance images, and clinical disease activity scores were obtained sequentially. Modest, but significant clinical improvement in skin, but not articular disease activity scores with only minor adverse effects was observed. Type 1, but not type 2 T cell cytokine production in vitro was suppressed in human rIL-10 compared with placebo recipients. Similarly, monokine production in vitro was reduced, whereas serum soluble TNFRII levels were elevated, indicating suppression of monocyte function. Decreased T cell and macrophage infiltration in synovial tissues was accompanied by reduced P-selectin expression. Moreover, suppressed synovial enhancement on magnetic resonance imaging and reduced alpha(v)beta(3) integrin expression on von Willebrand factor(+) vessels were observed. Together these data demonstrate that a short course of IL-10 modulates immune responses in vivo via diverse effects on endothelial activation, and leukocyte recruitment and effector function. Such biological changes may result in clinically meaningful improvement in disease activity.

New approaches to treatment in systemic vasculitis: biological therapies

Although the effectiveness of biological agents in systemic vasculitis is unproven, their introduction heralds a new era of vasculitis treatment. These agents offer the promise of targeted immunotherapies; the possibility of greater efficacy (and fewer side-effects) than conventional vasculitis treatments; and the potential to provide novel insights into the pathophysiology of these diseases-insights that may be gained only by using these agents in humans. Challenges to the investigation of these therapies in the systemic vasculitides exist, but important basic and clinical investigations are already in progress. We review the major issues facing the investigation of biological agents in vasculitis; examine the rationale for believing that biological strategies in vasculitis will be efficacious; identify several candidate targets for biological approaches; and discuss the results to date of early studies. The potential biological targets discussed include cytokines such as tumour necrosis factor; interleukins-1, -6, and -12; interferon-gamma; the co-stimulatory molecules B7-1 and B7-2; and others.