Biologic therapy for rheumatoid arthritis: clinical efficacy and predictors of response

Fibroblast Insights into the Pathogenesis of Ankylosing Spondylitis

Purpose of the Review

Emerging evidence has shown that ankylosing spondylitis fibroblasts (ASFs) act as crucial participants in inflammation and abnormal ossification in ankylosing spondylitis (AS). This review examines the investigations into ASFs and their pathological behavior, which contributes to inflammatory microenvironments and abnormal bone formation. The review spans the period from 2000 to 2023, with a primary focus on the most recent decade. Additionally, the review provides an in-depth discussion on studies on ASF ossification at the cellular level.

Recent Findings

ASFs organize immune functions by recruiting immune cells and influencing their differentiation and activation, thus mediate the inflammatory response in the early phase of disease. ASFs promote joint destruction at sites of cartilage and actively promote abnormal ossification by recruiting osteoblasts, differentiation into myofibroblasts or ossification directly. Many signaling pathways and cytokines such as Wnt signaling and BMP/TGF-β signaling are involved in ASF ossification.

Summary

ASFs play a key role in AS inflammation and osteogenesis. Further studies are required to elucidate molecular mechanisms behind that and provide new targets and directions for AS diagnosis and treatment from a new perspective of fibroblasts.

The Clinical Utility of Musculoskeletal Ultrasound for Disease Activity Evaluation and Therapeutic Response Prediction in Rheumatoid Arthritis Patients: A Narrative Review

Rheumatoid arthritis (RA) is characterized by persistent synovitis and joint/bone destruction. There is an unmet need to predict the therapeutic response to disease-modifying anti-rheumatic drugs (DMARDs) and achieve a treat-to-target goal. Musculoskeletal ultrasound (MSUS) is widely used to identify structural change and assess therapeutic response in RA. This review aims to summarize the available evidence regarding the clinical application of MSUS in evaluating disease activity and predicting therapeutic responses to DMARDs. We searched the MEDLINE database using the PubMed interface and reviewed English-language literature from 2000 to 2022. This review focuses on the updated role of MSUS in assessing disease activity and predicting therapeutic responses to DMARDs in RA patients. MSUS is now widely applied to identify articular structural change and assess the disease activity of RA. Combined use of gray scale and power Doppler MSUS is also superior to clinical assessment and laboratory examination in evaluating disease activity of RA. With portable use, good viability, and high sensitivity to articular inflammation, MSUS would be useful in assessing therapeutic response to biologic/targeted synthetic DMARDs (b/tsDMARDs) in RA patients. Given MSUS could also detect subclinical inflammation in a substantial proportion of RA patients with clinical remission, it is recommended to assess b/tsDMARDs-treated RA patients who have achieved low disease activity or remission. Although substantial literature data have revealed clinical utility of MSUS for monitoring disease activity and evaluating therapeutic response in RA patients, the evidence regarding its predictive value for the effectiveness of b/tsDMARDs is limited.

A green-lipped mussel prevents rheumatoid arthritis via regulation of inflammatory response and osteoclastogenesis

Rheumatoid arthritis (RA) is a chronic inflammatory disorder characterized by progressive joint destruction. Green-lipped mussel (GLM) has chondro-modulatory and anti-inflammatory properties, but the mechanism underlying the effect of GLM on RA is unclear. To investigate the roles of GLM on the pathogenesis of RA, we examined the effects of GLM in collagen-induced arthritis (CIA) mice and osteoclast differentiation. GLM was orally administrated CIA mice at 3 weeks after chicken type II collagen (CII) immunizations. GLM reduced arthritis severity and the histologic score of CIA mice compared to vehicle. The expression of proinflammatory cytokines (TNF-α, IL-1β, and IL-17) was decreased in the ankle joints of GLM-treated CIA mice. The expression of CD4+ IL-17+ cells decreased in ex vivo splenocytes and the spleens of GLM-treated CIA mice. Moreover, GLM inhibited TRAP+ multinucleated cells among mouse bone marrow-derived monocytes/macrophages (BMM), and the expression of osteoclast-related genes in mouse BMMs and human monocytes in vitro. These results suggest that GLM has potential as a therapeutic agent that can improve disease by controlling pathologic immune cells and osteoclastogenesis.

Rheumatoid Arthritis Versus Osteoarthritis in Patients Receiving Revision Total Knee Arthroplasty in the United States: Increased Perioperative Risks? A National Database-Based Propensity Score-Matching Study

BACKGROUND

The impacts of rheumatoid arthritis (RA) on perioperative risks among patients undergoing revision total knee arthroplasty (rTKA) have not been investigated yet. Thus, we hypothesized that patients with RA sustained increased perioperative risks and higher resource consumption burdens as compared to patients with osteoarthritis (OA) during the perioperative period.

PATIENTS AND METHODS

The National Inpatient Sample (NIS) database was used to compare the demographic characteristics, major in-hospital complications, resource consumptions, and in-hospitalization mortality between patients with RA and OA after rTKA. A 1:1 propensity score-matching, χ2 test, independence-sample T-test, and logistic regression analysis were done in statistical analyses to answer our hypotheses.

RESULTS

4.3% (6363/132,405) of rTKA patients were diagnosed with RA. They tended to be women and received revision for infection but with similar ages as compared to patients with OA. Except for acute postoperative anemia (odds ratio [OR] = 1.196), blood transfusion (OR = 1.179), prolonged hospitalization (OR = 1.049), and higher total cost (OR = 1.145), patients with RA sustained decreased odds of acute renal failure (OR = 0.804) and urinary complications (OR = 0.467). Besides, the other observed in-hospital complications showed no differences between patients with RA and OA.

CONCLUSION

Despite consuming greater in-hospital resources, patients with RA did not suffer increased odds of most in-hospital complications and in-hospital mortality for a revision TKA during the perioperative period. Compared with patients with OA, patients with RA sustained equivalent perioperative risks in the United States between 2002 and 2014.

Predictors of response to TNF inhibitors in rheumatoid arthritis: an individual patient data pooled analysis of randomised controlled trials

Objective

To identify patient characteristics associated with responsiveness to tumour necrosis factor inhibitors (TNFi) in rheumatoid arthritis (RA).

Materials and methods

Individual patient data from 29 randomised controlled trials (RCTs) evaluating the efficacy of a TNFi versus placebo or conventional therapy were obtained. Response to treatment was assessed in subgroups according to the following baseline characteristics: smoking status, physical activity, sex, age, body mass index, autoantibody profile, disease duration, high initial disease activity defined by Disease Activity Score on 28 joints (DAS28)(C reactive protein (CRP)) >5.1. The primary outcome was the between-treatment group difference in DAS28(CRP) change from baseline to 6 months. The secondary endpoints were the between-treatment group difference in final DAS28(CRP) measured until 6 months and EULAR response criteria until 6 months. Data from each RCT were then pooled by the Mantel-Haenszel method using a random effects model. A linear metaregression was also carried out on two data-sharing platforms separately to support the results.

Results

Individual data of 11 617 patients from 29 RCTs were analysed. Until 6 months, a significantly higher EULAR non-response rate was observed in obese patients (OR 0.52 vs 0.36 for non-obese, p=0.01). A multivariable regression model performed on 7457 patients indicated that patients treated by TNFi had a final DAS28(CRP) decreased by 0.02 for each year of disease duration (p<0.001), and a 0.21 decreased for patients with a baseline DAS28(CRP) >5.1 (p<0.001).

Conclusions

In RA, patients who are more responsive to TNFi are those who are non-obese, have a long disease duration and have a high initial disease activity.

Bioactive fractions and compound of Ardisia crispa roots exhibit anti-arthritic properties mediated via angiogenesis inhibition in vitro

Background

Ardisia crispa (Thunb.) A.DC (Primulaceae), is a medicinal herb traditionally used by Asian people as remedies to cure inflammatory related diseases, including rheumatism. The plant roots possess various pharmacological activities including antipyretic, anti-inflammation and antitumor. Previous phytochemical studies of the plant roots have identified long chain alkyl-1,4-benzoquinones as major constituents, together with other phytochemicals. Hexane fraction of the plant roots (ACRH), was previously reported with anti-angiogenic and anti-arthritic properties, while its effect on their anti-arthritic in vitro, is yet unrevealed. Considering the significance of angiogenesis inhibition in developing new anti-arthritic agent, thus we investigated the anti-arthritic potential of Ardisia crispa roots by suppressing angiogenesis, in vitro.

Methods

Ardisia crispa roots hexane extract (ACRH) was prepared from the plant roots using absolute n-hexane. ACRH was fractionated into quinone-rich fraction (QRF) and further isolated to yield benzoquinonoid compound (BQ), respectively. In vitro experiments using VEGF-induced human umbilical vein endothelial cells (HUVECs) and IL-1β-induced human fibroblast-like synoviocytes for rheumatoid arthritis (HFLS-RA) were performed to evaluate the effects of these samples on VEGF-induced HUVECs proliferation and tube formation, and towards IL-1β-induced HFLS-RA proliferation, invasion, and apoptosis, respectively. Therapeutic concentrations (0.05, 0.5, and 5 μg/mL) tested in this study were predetermined based on the IC₅₀ values obtained from the MTT assay.

Results

ACRH, QRF, and BQ exerted concentration-independent antiproliferative effects on VEGF-induced HUVECs and IL-1β-induced HFLS-RA, with IC₅₀ values at 1.09 ± 0.18, 3.85 ± 0.26, and 1.34 ± 0.16 μg/mL in HUVECs; and 3.60 ± 1.38, 4.47 ± 0.34, and 1.09 ± 0.09 μg/mL in HFLS-RA, respectively. Anti-angiogenic properties of these samples were verified via significant inhibition on VEGF-induced HUVECs tube formation, in a concentration-independent manner. The invasiveness of IL-1β-induced HFLS-RA was also significantly inhibited in a concentration-independent manner by all samples. ACRH and BQ, but not QRF, significantly enhanced the apoptosis of IL-1β-induced HFLS-RA elicited at their highest concentration (5 μg/mL) (P < 0.05).

Conclusions

These findings highlight the bioactive fractions and compound from Ardisia crispa roots as potential anti-arthritic agents by inhibiting both HUVECs and HFLS-RA’s cellular functions in vitro, possibly mediated via their anti-angiogenic effects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03341-y.

Pharmacogenetics of TNF inhibitor response in rheumatoid arthritis utilizing the two-component disease activity score

Aim:

TNF inhibitor drugs are a treatment option for rheumatoid arthritis, but response is not universal. Response is typically measured using the composite 4-component (4C) disease activity score 28 (DAS28) which contains more subjective measures. This study used a validated 2-component (2C) DAS28 score to determine whether SNPs associated with response were replicated in the UK population.

Materials & methods:

A literature review identified TNF inhibitor response SNPs. Linear regression was conducted to replicate associations with 4C or 2C-DAS28 response.

Results:

Eighteen independent SNPs were analyzed in 1828 patients. One and four associations with 4C and 2C-DAS28 response respectively were identified (p ≤ 0.05).

Conclusion:

Further genetic associations were replicated using the 2C-DAS28 which may reflect the objective nature of 2C-AS28.

The Abnormal CD4+T Lymphocyte Subset Distribution and Vbeta Repertoire in New-onset Rheumatoid Arthritis Can Be Modulated by Methotrexate Treament

Patients with long-term, treated, rheumatoid arthritis (RA) show abnormalities in their circulating CD4+ T-lymphocytes, but whether this occurs in recently diagnosed naïve patients to disease-modifying drugs (DMARDs) is under discussion. These patients show heterogeneous clinical response to methotrexate (MTX) treatment. We have examined the count of circulating CD4+ T-lymphocytes, and their naïve (TN), central memory (TCM), effector memory (TEM) and effector (TE) subsets, CD28 expression and Vβ TCR repertoire distribution by polychromatic flow cytometry in a population of 68 DMARD-naïve recently diagnosed RA patients, before and after 3 and 6 months of MTX treatment. At pre-treatment baseline, patients showed an expansion of the counts of CD4+ TN, TEM, TE and TCM lymphocyte subsets, and of total CD4+CD28- cells and of the TE subset with a different pattern of numbers in MTX responder and non-responders. The expansion of CD4+TEM lymphocytes showed a predictive value of MTX non-response. MTX treatment was associated to different modifications in the counts of the CD4+ subsets and of the Vβ TCR repertoire family distribution and in the level of CD28 expression in responders and non-responders. In conclusion, the disturbance of CD4+ lymphocytes is already found in DMARD-naïve RA patients with different patterns of alterations in MTX responders and non-responders.

Rheumatoid arthritis synovial fibroblasts promote TREM-1 expression in monocytes via COX-2/PGE2 pathway

BACKGROUND

Triggering receptor expressed on myeloid cells-1 (TREM-1) is inducible on monocyte/macrophages and neutrophils and amplifies the inflammatory response. The aim of this study was to determine whether rheumatoid arthritis synovial fibroblasts (RASF) promote the expression of TREM-1 in monocytes and its potential regulatory mechanism.

METHODS

Synovial fluid and paired peripheral blood from rheumatoid arthritis (RA) patients were analyzed using flow cytometry. Expression of TREM-1 in monocytes was detected after co-culture with RASF, with or without pre-treatment with toll-like receptor (TLR) ligands. Whether RASF-regulated TREM-1 level in monocytes require direct cell contact or soluble factors was evaluated by transwell experiment. COX-2 expression and PGE₂ secretion in RASF were determined by quantitative PCR (qPCR) and ELISA. RASF, with and without TLR ligand stimulation, were treated with COX-2 inhibitors, COX-2 siRNA (siCOX-2) or EP1-4 antagonists, and the resulting TREM-1 level in CD14⁺ monocytes was measured using flow cytometry.

RESULTS

TREM-1 was highly expressed in CD14⁺ cells from peripheral blood and especially synovial fluid from RA patients. The expression of TREM-1 in monocytes was increased by co-culture with RASF. TLR-ligand-activated RASF further elevated TREM-1 level. Transwell assay indicated that soluble factors played a key role in RASF-promoted expression of TREM-1 in monocytes. RASF, with or without stimulation by TLR ligands, increased secretion of PGE₂ in a cyclooxygenase (COX)-2-dependent manner. PGE₂ enhanced the increase in TREM-1 level in monocytes. Finally, studies using COX-2 inhibitors, COX-2 siRNA (siCOX-2) and EP1-4 antagonists, showed that RASF promotion of TREM-1 expression in monocytes was mediated by COX-2/PGE₂/EP2,4 signaling.

CONCLUSIONS

Our data is the first report to reveal the critical role of RASF in upregulating TREM-1 expression in monocytes, which indicates that TREM-1 might be a novel target for RA therapy.

Rheumatoid factor as predictor of response to treatment with anti-TNF alpha drugs in patients with rheumatoid arthritis: Results of a cohort study

We determined whether rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibody (ACPA) can predict remission or severe disability in rheumatoid arthritis (RA) patients treated with anti-tumor necrosis factor (TNF) alpha drugs.We performed a cohort study based on the clinical data from a referral center for the treatment of RA in Bogotá, Colombia, were included patients aged ≥18 years with diagnosis of RA with an active disease and for whom a treatment scheme was begun with anti-TNF alpha medication, with a minimum follow-up time of 12 months. Disease activity of Rheumatoid Arthritis was assessed through measurement of RF, ACPA, disease activity score (DAS28), and health assessment questionnaire (HAQ). We calculated the incidence rates (IRs) for remission and severe disability. We also calculated the incidence rate ratio (IRR) for each outcome by adjusting for possible confounders using the Poisson regression method. The hypothesis was tested with a P value of <.05. Statistical analysis was performed in Stata 15.We included 400 patients receiving an anti-TNF alpha agent. Median age was 60 years, and 322 patients were women (80.5%). RF was positive in 357 patients (89%), ACPA in 348 patients (87%), and co-positivity in 324 patients (81%). Median follow-up was 41 months (range, 12-79 months). The IR for remission was 23 per 100 person-years in RF-negative patients and 16 per 100 person-years in RF-positive patients. The adjusted IRR (age sex, treatment, and ACPA) was 1.51 (95%CI, 1.05-2.18). The IR for severe disability was 10.8 per 100 person-years in the RF-positive cohort and 2.3 per 100 person-years in the RF-negative cohort. The IRR adjusted for these factors was 4.37 (95%CI, 1.6-12). Co-positivity had a similar behavior to RF. No differences were recorded in the rates of remission or disability in ACPA-positive and ACPA-negative patients.Our findings suggest that remission is less frequent and severe disability more frequent in RF-positive patients treated with anti-TNF alpha agents than in RF-negative patients.

Hydroquinone exposure worsens the symptomatology of rheumatoid arthritis

The genesis of rheumatoid arthritis (RA) is complex and dependent on genetic background and exposure to environmental xenobiotic. Indeed, smoking is associated to developing and worsening pre-existing RA. Nevertheless, the mechanisms and cigarette compounds involved in the harmful processes have not been elucidated. Here, we investigated if the exposure to hydroquinone (HQ), an abundant pro-oxidative compound of cigarette and benzene metabolite, could worsen the ongoing RA. Hence, collagen-induced arthritis (CIA) was induced in male Wistar rats by s.c. injection of 400 μg (200 μL) of bovine collagen type II emulsified in complete Freund's adjuvant on day 1, and a booster injection was performed on day 7. Exposures to nebulized HQ (25 ppm), saline solution or HQ vehicle solution (5% ethanol in saline) were carried out for 1 h, once a day, on days 21-27 after CIA induction. On day 27, animals were euthanized and samples were collected for further analyses. Exposure to HQ caused loss of weight, intensified paw edema, enhanced levels of tumor necrosis factor-α (TNF-α) and anti-citrullinated protein antibody (ACPA) in the serum; augmented synoviocyte proliferation and influx of aril hydrocarbon receptor (AhR) positive cells into the synovial membrane, altered collagen fibre rearrangement in the synovia, and synoviocytes isolated from HQ exposed rats secreted higher levels of pro-inflammatory cytokines, TNF-α and interleukin-1β. Associated, we point out HQ as an environmental pollutant that aggravates RA, suggesting its participation on worsening RA in smoking patients.

Precision Medicine in Rheumatoid Arthritis

Treatment of rheumatoid arthritis (RA) has substantially improved in recent years because of the development of novel drugs. However, response is not universal for any of the treatment options, and selection of an effective therapy is currently based on a trial-and-error approach. Delayed treatment response increases the risk of progressive joint damage and resultant disability and also has a significant impact on quality of life for patients. For many drugs, the patient's genetic background influences response to therapy, and understanding the genetics of response to therapy in RA may allow for targeted personalized health care.

Inflammatory but not mitogenic contexts prime synovial fibroblasts for compensatory signaling responses to p38 inhibition

Rheumatoid arthritis (RA) is a chronic inflammatory disorder that causes joint pain, swelling, and loss of function. Development of effective new drugs has proven challenging in part because of the complexities and interconnected nature of intracellular signaling networks that complicate the effects of pharmacological interventions. We characterized the kinase signaling pathways that are activated in RA and evaluated the multivariate effects of targeted inhibitors. Synovial fluids from RA patients activated the kinase signaling pathways JAK, JNK, p38, and MEK in synovial fibroblasts (SFs), a stromal cell type that promotes RA progression. Kinase inhibitors enhanced signaling of "off-target" pathways in a manner dependent on stimulatory context. Inhibitors of p38, which have been widely explored in clinical trials for RA, resulted in undesirable increases in nuclear factor κB (NF-κB), JNK, and MEK signaling in SFs in inflammatory, but not mitogenic, contexts. This was mediated by the transcription factor CREB, which functions in part within a negative feedback loop in MAPK signaling. CREB activation was induced predominately by p38 in response to inflammatory stimuli, but by MEK in response to mitogenic stimuli; hence, the effects of drugs targeting p38 or MEK were markedly different in SFs cultured under mitogenic or inflammatory conditions. Together, these findings illustrate how stimulatory context can alter dominance in pathway cross-talk even for a fixed network topology, thereby providing a rationale for why p38 inhibitors deliver limited benefits in RA and demonstrating the need for careful consideration of p38-targeted drugs in inflammation-related disorders.

High titers of both rheumatoid factor and anti-CCP antibodies at baseline in patients with rheumatoid arthritis are associated with increased circulating baseline TNF level, low drug levels, and reduced clinical responses: a post hoc analysis of the RISING study

Background

Although both rheumatoid factor (RF) and anticyclic citrullinated peptide antibodies (anti-CCP) are useful for diagnosing rheumatoid arthritis (RA), the impact of these autoantibodies on the efficacy of tumor necrosis factor (TNF) inhibitors has been controversial. The aim of this post hoc analysis of a randomized double-blind study (the RISING study) was to investigate the influences of RF and anti-CCP on the clinical response to infliximab in patients with RA.

Methods

Methotrexate-refractory patients with RA received 3 mg/kg of infliximab from weeks 0 to 6 and then 3, 6, or 10 mg/kg every 8 weeks from weeks 14 to 46. In this post hoc analysis, patients were stratified into three classes on the basis of baseline RF/anti-CCP titers: “low/low-C” (RF < 55 IU/ml, anti-CCP < 42 U/ml), “high/high-C” (RF ≥ 160 IU/ml, anti-CCP ≥ 100 U/ml), and “middle-C” (neither low/low-C nor high/high-C). Baseline plasma TNF level, serum infliximab level, and disease activity were compared between the three classes.

Results

Baseline RF and anti-CCP titers showed significant correlations with baseline TNF and infliximab levels in weeks 2–14. Comparison of the three classes showed that baseline TNF level was lowest in the low/low-C group and highest in the high/high-C group (median 0.73 versus 1.15 pg/ml), that infliximab levels at week 14 were highest in the low/low-C group and lowest in the high/high-C group (median 1.0 versus 0.1 μg/ml), and that Disease Activity Score in 28 joints based on C-reactive protein at week 14 was lowest in the low/low-C group and highest in the high/high-C group (median 3.17 versus 3.82). A similar correlation was observed at week 54 in the 3 mg/kg dosing group, but not in the 6 or 10 mg/kg group. Significant decreases in both RF and anti-CCP were observed during infliximab treatment.

Conclusions

RF/anti-CCP titers correlated with TNF level. This might explain the association of RF/anti-CCP with infliximab level and clinical response in patients with RA. Baseline RF/anti-CCP titers may serve as indices that aid infliximab treatment.

Trial registration

ClinicalTrials.gov, NCT00691028. Retrospectively registered on 3 June 2008.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1401-2) contains supplementary material, which is available to authorized users.

DNA methylation as a marker of response in rheumatoid arthritis

Rheumatoid arthritis (RA) is a complex disease affecting approximately 0.5-1% of the population. While there are effective biologic therapies, in up to 40% of patients, disease activity remains inadequately controlled. Therefore, identifying factors that predict, prior to the initiation of therapy, which patients are likely to respond best to which treatment is a research priority and DNA methylation is increasingly being explored as a potential theranostic biomarker. DNA methylation is thought to play a role in RA disease pathogenesis and in mediating the relationship between genetic variants and patient outcomes. The role of DNA methylation has been most extensively explored in cancer medicine, where it has been shown to be predictive of treatment response. Studies in RA, however, are in their infancy and, while showing promise, further investigation in well-powered studies is warranted.

Therapeutic Drug Monitoring and Clinical Outcomes in Immune Mediated Diseases: The Missing Link

As the incidence of inflammatory bowel diseases and the number of patients treated with anti-TNF agents keep on increasing so are the phenomena of primary non response (PNR) and secondary loss of response (SLR) to these medications. Traditionally PNR and SLR have been managed empirically-that is, switching medications for PNR and increasing the anti-TNF dose for SNR. More recently an approach based on testing drug levels and antibodies to the drug (therapeutic drug monitoring) has gained increasing popularity in the management of inflammatory bowel diseases. However, while this strategy might offer an insight into the mechanisms leading to PNR/SLR it often falls short of providing a simple, reproducible method to manage these issues in clinical practice. Here, we will review the currently recommended therapeutic strategies when using therapeutic drug monitoring; the evidence for and against such approach and the current standard strategies in Rheumatology (the specialty with the largest and longest experience with anti-TNF agents). We will then discuss the possible reasons of the shortcomings of therapeutic drug monitoring and the rationale and need to move the therapeutic target to the disease burden in inflammatory bowel diseases-along with the supporting preliminary evidence. Finally, we will focus on future crucial studies that need to be done to make approaches to PNR/SLR more rigorous and at the same time user-friendly for the practicing gastroenterologist.

Inhibition of cytokine response to TLR stimulation and alleviation of collagen-induced arthritis in mice by Schistosoma japonicum peptide SJMHE1

Helminth‐derived products have recently been shown to prevent the development of inflammatory diseases in mouse models. However, most identified immunomodulators from helminthes are mixtures or macromolecules with potentially immunogenic side effects. We previously identified an immunomodulatory peptide called SJMHE1 from the HSP60 protein of Schistosoma japonicum. In this study, we assessed the ability of SJMHE1 to affect murine splenocytes and human peripheral blood mononuclear cells (PBMCs) stimulated by toll‐like receptor (TLR) ligands in vitro and its treatment effect on mice with collagen‐induced arthritis (CIA). We show that SJMHE1 not only modulates the cytokine production of murine macrophage (MΦ) and dendritic cell but also affects cytokine production upon coculturing with allogeneic CD4⁺ T cell. SJMHE1 potently inhibits the cytokine response to TLR ligands lipopolysaccharide (LPS), CpG oligodeoxynucleotides (CpG) or resiquimod (R848) from mouse splenocytes, and human PBMCs stimulated by LPS. Furthermore, SJMHE1 suppressed clinical signs of CIA in mice and blocked joint erosion progression. This effect was mediated by downregulation of key cytokines involved in the pathogenesis of CIA, such as interferon‐γ (IFN‐γ), tumour necrosis factor‐α (TNF‐α), interleukin (IL)‐6, IL‐17, and IL‐22 and up‐regulation of the inhibitory cytokine IL‐10, Tgf‐β1 mRNA, and CD4⁺CD25⁺Foxp3⁺ Tregs. This study provides new evidence that the peptide from S. japonicum, which is the ‘safe’ selective generation of small molecule peptide that has evolved during host–parasite interactions, is of great value in the search for novel anti‐inflammatory agents and therapeutic targets for autoimmune diseases.

Standardized Whole-Blood Transcriptional Profiling Enables the Deconvolution of Complex Induced Immune Responses

Systems approaches for the study of immune signaling pathways have been traditionally based on purified cells or cultured lines. However, in vivo responses involve the coordinated action of multiple cell types, which interact to establish an inflammatory microenvironment. We employed standardized whole-blood stimulation systems to test the hypothesis that responses to Toll-like receptor ligands or whole microbes can be defined by the transcriptional signatures of key cytokines. We found 44 genes, identified using Support Vector Machine learning, that captured the diversity of complex innate immune responses with improved segregation between distinct stimuli. Furthermore, we used donor variability to identify shared inter-cellular pathways and trace cytokine loops involved in gene expression. This provides strategies for dimension reduction of large datasets and deconvolution of innate immune responses applicable for characterizing immunomodulatory molecules. Moreover, we provide an interactive R-Shiny application with healthy donor reference values for induced inflammatory genes.

Blood-based identification of non-responders to anti-TNF therapy in rheumatoid arthritis

BACKGROUND

Faced with an increasing number of choices for biologic therapies, rheumatologists have a critical need for better tools to inform rheumatoid arthritis (RA) disease management. The ability to identify patients who are unlikely to respond to first-line biologic anti-TNF therapies prior to their treatment would allow these patients to seek alternative therapies, providing faster relief and avoiding complications of disease.

METHODS

We identified a gene expression classifier to predict, pre-treatment, which RA patients are unlikely to respond to the anti-TNF infliximab. The classifier was trained and independently evaluated using four published whole blood gene expression data sets, in which RA patients (n = 116 = 44 + 15 + 30 + 27) were treated with infliximab, and their response assessed 14-16 months post treatment according to the European League Against Rheumatism (EULAR) response criteria. For each patient, prior knowledge was used to group gene expression measurements into disease-relevant biological signaling mechanisms that were used as the input features for regularized logistic regression.

RESULTS

The classifier produced a substantial enrichment of non-responders (59 %, given by the cross validated test precision) compared to the full population (27 % non-responders), while identifying nearly a third of non-responders. Given this classifier performance, treatment of predicted non-responders with alternative biologics would decrease their chance of non-response by between a third and a half, substantially improving their odds of effective treatment and stemming further disease progression. The classifier consisted of 18 signaling mechanisms, which together indicated that higher inflammatory signaling mediated by TNF and other cytokines was present pre-treatment in the blood of patients who responded to infliximab treatment. In contrast, non-responders were classified by relatively higher levels of specific metabolic activities in the blood prior to treatment.

CONCLUSIONS

We were able to successfully produce a classifier to identify a population of RA patients significantly enriched in anti-TNF non-responders across four different patient cohorts. Additional prospective studies are needed to validate and refine the classifier for clinical use.

The number of circulating monocytes as biomarkers of the clinical response to methotrexate in untreated patients with rheumatoid arthritis

Background

The aim of this work was to analyze the number and distribution of circulating monocytes, and of their CD14^+highCD16⁻, CD14^+highCD16⁺ and CD14^+lowCD16⁺ subset cells, in treatment-naive patients with rheumatoid arthritis (RA), and to determine their value in predicting the clinical response to methotrexate (MTX) treatment.

Methods

This prospective work investigated the number of circulating monocytes, and the numbers of CD14^+highCD16⁻, CD14^+highCD16⁺ and CD14^+lowCD16⁺ subset cells, in 52 untreated patients with RA before MTX treatment, and at 3 and 6 months into treatment, using flow cytometry.

Results

The absolute number of circulating monocytes, and the numbers of CD14^+highCD16⁻, CD14^+highCD16⁺ and CD14^+lowCD16⁺ subset cells, were significantly higher in MTX non-responders than in responders and healthy controls before starting and throughout treatment. Responders showed normal numbers of monocytes, and of their subset cells, over the study period. The pre-treatment absolute number of circulating monocytes, and the numbers of CD14^+highCD16⁻ and CD14^+highCD16⁺ subset cells, were found to be predictive of the clinical response to MTX, with a sensitivity and specificity of >70% and >88%, respectively.

Conclusions

Treatment-naive patients with RA showed an anomalous distribution of circulating monocyte subsets, and an anomalous number of cells in each subset. A higher pre-treatment number of circulating monocytes, and higher numbers of CD14^+highCD16⁻ and CD14^+highCD16⁺ subset cells, predict a reduced clinical response to MTX in untreated patients with RA.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-014-0375-y) contains supplementary material, which is available to authorized users.

Smoking and rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory disease caused by both genetic and environmental factors. Smoking has been implicated as one of the most important extrinsic risk factors for its development and severity. Recent developments have shed light on the pathophysiology of RA in smokers, including oxidative stress, inflammation, autoantibody formation and epigenetic changes. The association of smoking and the development of RA have been demonstrated through epidemiologic studies, as well as through in vivo and animal models of RA. With increased use of biological agents in addition to standard disease-modifying antirheumatic drugs (DMARDs), there has been interest in how smoking affects drug response in RA treatment. Recent evidence suggests the response and drug survival in people treated with anti-tumour necrosis factor (anti-TNF) therapy is poorer in heavy smokers, and possible immunological mechanisms for this effect are presented in the current paper.

Down-regulating peroxisome proliferator-activated receptor-gamma coactivator-1 beta alleviates the proinflammatory effect of rheumatoid arthritis fibroblast-like synoviocytes through inhibiting extracellular signal-regulated kinase, p38 and nuclear factor-kappaB activation

Introduction

Rheumatoid arthritis (RA) is a chronic inflammatory disease leading to joint destruction and disability. Peroxisome proliferator-activated receptor-gamma coactivator-1beta (PGC-1β) is a transcriptional coactivator that plays important roles in regulating multiple aspects of energy metabolism and cytokine signaling pathways. PGC-1β overexpression leads to the attenuation of macrophage-mediated inflammation. In this study, we aimed to determine the expression of PGC-1β in RA synovium and fibroblast-like synoviocytes (FLS), and explore the mechanisms of PGC-1β on both the proinflammatory effects and apoptosis in RA-FLS.

Methods

Synovium was obtained from 31 patients with active RA, as well as 13 osteoarthritis (OA) and 10 orthopedic arthropathies (Orth.A) as “less inflamed” disease controls. FLS were then isolated and cultured. Synovial PGC-1β expression was determined by immunohistochemistry staining, while FLS PGC-1β expression was detected by immunofluorescence staining, quantitative real-time PCR (qPCR) assay and western blot. PGC-1β was depleted by lentivirus sh-RNA, and up-regulated by pcDNA3.1- PGC-1β. The expression of proinflammatory cytokines, matrix metalloproteinases and receptor activator of nuclear factor-kappaB ligand was analyzed by qPCR, cytometric bead array and western blot. The expression of mitogen-activated protein kinases and nuclear factor-kappaB (NF-κB) was determined by qPCR and western blot. Besides, cell apoptosis was examined using flow cytometry. The interaction between PGC-1β and NF-κB was performed by dual-luciferase reporter gene assays.

Results

(A) Synovial PGC-1β was over-expressed in RA patients compared with OA or Orth.A patients. (B) PGC-1β expression significantly increased in RA-FLS compared with OA-FLS. (C) PGC-1β mediated the expression of proinflammatory cytokines and apoptosis through extracellular signal-regulated kinase (ERK), p38 and NF-κB in RA-FLS. (D) PGC-1β mediated NF-κB transcription in RA-FLS, but did not affect ERK and p38.

Conclusion

The results indicate that PGC-1β may play important roles in the proinflammatory effects and apoptosis of RA-FLS.

Lack of validation of genetic variants associated with anti-tumor necrosis factor therapy response in rheumatoid arthritis: a genome-wide association study replication and meta-analysis

INTRODUCTION

In this study, our aim was to elucidate the role of four polymorphisms identified in a prior large genome-wide association study (GWAS) in which the investigators analyzed the responses of patients with rheumatoid arthritis (RA) to treatment with tumor necrosis factor inhibitors (TNFi). The authors of that study reported that the four genetic variants were significantly associated. However, none of the associations reached GWAS significance, and two subsequent studies failed to replicate these associations.

METHODS

The four polymorphisms (rs12081765, rs1532269, rs17301249 and rs7305646) were genotyped in a total of 634 TNFi-treated RA patients of Spanish Caucasian origin. Four outcomes were evaluated: changes in the Disease Activity Score in 28 joints (DAS28) after 6 and 12 months of treatment and classification according to the European League Against Rheumatism (EULAR) response criteria at the same time points. Association with DAS28 changes was assessed by linear regression using an additive genetic model. Contingency tables of genotype and allele frequencies between EULAR responder and nonresponder patients were compared. In addition, we combined our data with those of previously reported studies in a meta-analysis including 2,998 RA patients.

RESULTS

None of the four genetic variants showed an association with response to TNFi in any of the four outcomes analyzed in our Spanish patients. In addition, only rs1532269 yielded a suggestive association (P = 0.0033) with the response to TNFi when available data from previous studies were combined in the meta-analysis.

CONCLUSION

Our data suggest that the rs12081765, rs1532269, rs17301249 and rs7305646 genetic variants do not have a role as genetic predictors of TNFi treatment outcomes.

The status of rheumatoid factor and anti-cyclic citrullinated peptide antibody are not associated with the effect of anti-TNFα agent treatment in patients with rheumatoid arthritis: a meta-analysis

Objectives

This meta-analysis was conducted to investigate whether the status of rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibody are associated with the clinical response to anti-tumor necrosis factor (TNF) alpha treatment in rheumatoid arthritis (RA).

Methods

A systemic literature review was performed using the MEDLINE, SCOPUS, Cochrane Library, ISI Web of Knowledge, and Clinical Trials Register databases, and Hayden's criteria of quality assessment for prognostic studies were used to evaluate all of the studies. The correlation between the RF and anti-CCP antibody status with the treatment effect of anti-TNFα agents was analyzed separately using the Mantel Haenszel method. A fixed-effects model was used when there was no significant heterogeneity; otherwise, a random-effects model was applied. Publication bias was assessed using Egger's linear regression and a funnel plot.

Results

A total of 14 studies involving 5561 RA patients meeting the inclusion criteria were included. The overall analysis showed that the pooled relative risk for the predictive effects of the RF and anti-CCP antibody status on patient response to anti-TNFα agents was 0.98 (95% CI: 0.91–1.05, p = 0.54) and 0.88 (95% CI: 0.76–1.03, p = 0.11), respectively, with I² values of 43% (p = 0.05) and 67% (p<0.01), respectively. Subgroup analyses of different anti-TNFα treatments (infliximab vs. etanercept vs. adalimumab vs. golimumab), response criteria (DAS28 vs. ACR20 vs. EULAR response), follow-up period (≥6 vs. <6 months), and ethnic group did not reveal a significant association for the status of RF and anti-CCP.

Conclusions

Neither the RF nor anti-CCP antibody status in RA patients is associated with a clinical response to anti-TNFα treatment.

Predictors of response and remission in a large cohort of rheumatoid arthritis patients treated with tocilizumab in clinical practice

OBJECTIVE

The objective of this study was to identify predictors of response and remission to tocilizumab (TCZ) in RA patients seen in daily routine clinical practice.

METHODS

The efficacy of TCZ was evaluated after 12 and 24 weeks of treatment by the European League Against Rheumatism (EULAR) response criteria. Regression analysis was performed to study the association between remission or EULAR response and the following characteristics: gender, age, current smokers, prior cardiovascular disease (CVD), 28-joint disease activity score (DAS28), CRP, RF or ACPA positivity, combination therapy with DMARDs and TCZ as the first biological therapy or after failure of at least one biological therapy.

RESULTS

In total, 204 patients were included with a mean DAS28 score of 5.14. EULAR response and remission were obtained in 86.1% and 40% of patients, respectively, at week 24. In multiple regression analysis, a high baseline CRP level [odds ratio (OR) 4.454 (95% CI 1.446, 13.726)] was significantly associated with EULAR response at week 24 and, inversely, age >55 years [OR 0.285 (95% CI 0.086, 0.950)] and prior CVD [OR 0.305 (95% CI 0.113, 0.825)] were significantly associated with lower EULAR response at week 24. Older age was also associated with less remission at week 24 [OR 0.948 (95% CI 0.920, 0.978)]. No additional effectiveness was found when TCZ was used in combination with a DMARD or when patients were naive to biological agents.

CONCLUSION

In daily practice we identified three predictors of a better response for TCZ therapy in RA: a younger age, a high baseline CRP level and no history of CVD.

Immediate splenectomy down-regulates the MAPK-NF-κB signaling pathway in rat brain after severe traumatic brain injury

BACKGROUND

The treatment of severe traumatic brain injury (TBI) remains a difficult process. One key to improving treatment efficacy is to reduce secondary brain injury. Local and systemic inflammatory responses play an important role in secondary injury after TBI, which if unchecked can lead to fatal cerebral edema. Previous studies focused mainly on local brain tissue, whereas little is known about the contribution of peripheral organs in the pathogenesis of TBI. We previously showed that immediate splenectomy decreases mortality and improves cognitive function in rats after severe TBI by inhibiting the release of proinflammatory cytokines both systematically and locally in the injured brain. In this study, we further investigated the molecular mechanisms responsible for the effect of the spleen on local brain inflammation after TBI.

METHODS

We established a severe TBI model with rats and performed splenectomy to study the effect of the spleen on mitogen-activated protein kinase (MAPK)-NF-κB activation in the brain tissue. The expression of p38 MAPK, extracellular regulated protein kinases (ERK), and NF-κB protein in the trauma region was examined by Western blotting. The neuron-like PC-12 cell line and microglia-like BV-2 cell line were used for in vitro experiments to test the effects of spleen supernatant after TBI. Cell apoptosis (annexin V/propidium iodide staining), NF-κB nuclear translocation (immunofluorescence microscopy), and MAPK signaling (phosphorylation of p-p38 and p-ERK) were examined.

RESULTS

We found that TBI significantly up-regulated MAPK signaling in the injured brain region, whereas immediate splenectomy suppressed MAPK activation. In vitro, the spleen supernatant from rats after TBI also resulted in increased MAPK activation and NF-κB nuclear translocation in microglia-like BV-2 cells, whereas the application of interleukin (IL)-1R antagonist (IL-1Ra) significantly reduced the expression of p-p38 and p-ERK as well as NF-κB nuclear translocation. In addition, spleen supernatant after TBI induced apoptosis in neuron-like PC-12 cells, and IL-1Ra could effectively reduce apoptosis.

CONCLUSION

Our study demonstrates that immediate splenectomy down-regulates the MAPK-NF-κB signaling pathway in rat brain after severe TBI. We also provide experimental evidence for the potential use of IL-1Ra to alleviate brain inflammation after TBI.

The frequency of anti-infliximab antibodies in patients with rheumatoid arthritis treated in routine care and the associations with adverse drug reactions and treatment failure

OBJECTIVES

To investigate the frequency of anti-infliximab antibodies in patients with RA and the associations with adverse drug reactions and treatment failure.

METHODS

Based on the DANBIO registry, patients with RA who initiated treatment with infliximab at Hvidovre Hospital between 2000 and 2008 and had available serum samples were identified. The patients were followed for 52 weeks. Anti-infliximab antibodies were determined prior to infusion at baseline and during follow-up (weeks 2, 6, 14 and 52 or at withdrawal) using the IMPACT indirect assay (Roche Diagnostics) and merged with clinical data prospectively registered in the DANBIO registry.

RESULTS

A total of 218 patients with RA were included (80% females, median age 56 years, disease duration 10 years, 65% RF positive, median DAS28 = 5.0). During the 52-week follow-up, 28 patients (13%) withdrew due to adverse events and 50 (23%) due to treatment failure. Antibodies were detected in 118 patients (54%) during follow-up. Patients with detectable anti-infliximab antibodies after 6 weeks had an increased risk of adverse drug reactions [hazard ratio (HR) = 5.06, 95% CI 2.36, 10.84; P < 0.0001] compared with patients without anti-infliximab antibodies. Similar results were observed in patients with anti-infliximab antibodies after 14 weeks (HR = 3.30, 95% CI 1.56, 6.99; P = 0.0009). Patients with detectable anti-infliximab antibodies during the 52-week follow-up were less likely to achieve sustained minimal disease activity and remission.

CONCLUSION

Early anti-infliximab antibody formation increased the risk of adverse drug reactions, including infusion reactions. Anti-infliximab antibody formation during the 52-week follow-up decreased the likelihood of minimal disease activity and remission in patients with RA treated in routine care.

Rheumatoid factor as predictor of response to abatacept, rituximab and tocilizumab in rheumatoid arthritis: Systematic review and meta-analysis

OBJECTIVE

To identify if rheumatoid factor (RF) is predictor of response to rituximab (RTX), abatacept (ABT), and tocilizumab (TCZ) in rheumatoid arthritis (RA).

METHODS

Systematic review and meta-analysis of clinical trials and observational studies based on a sensitive search. Meta-regression was used to explore causes of heterogeneity. Unpublished data of clinical trials provided by the authors were also included.

RESULTS

The electronic search captured 3221 references and 422 meeting abstracts. By hand search, four additional articles were also identified. A total of 23 studies meet the purpose of the study and were included in the review. RF positivity at starting predicts better ACR20 [OR, 1.95 (1.24, 3.08)], ACR50 [OR, 5.38 (2.50, 11.60)] and EULAR response [OR, 3.52 (1.66, 7.45)] in 14 studies with RTX, and better ACR20 [OR, 1.51 (1.21, 1.90)] in 6 studies with TCZ. In 3 studies with ABT, no association was found between response and RF [OR 1.36 (0.97, 1.90)]. No asymmetries in the funnel plots or significant variables were found in the meta-regression.

CONCLUSION

In RA, RF positivity predicts better response to RTX and TCZ but not to ABT.

Investigation of single nucleotide polymorphisms and biological pathways associated with response to TNFα inhibitors in patients with rheumatoid arthritis

OBJECTIVE

Recently, two genome-wide association studies identified single nucleotide polymorphisms (SNPs) significantly associated with the treatment response to tumor necrosis factor α (TNFα) inhibitors in patients with rheumatoid arthritis (RA). We aimed to replicate these results and identify SNPs and the possible biological pathways associated with the treatment response to TNFα inhibitors.

METHODS

TNFα-naive patients with RA, who had available DNA and initiated TNFα inhibitor therapy between 1999 and 2008, were identified in the DANBIO registry and genotyped using the Illumina HumanHap550K Duo array. The associations between SNPs and changes in the absolute and the relative Disease Activity Score, and European League Against Rheumatism good versus no response after 14 weeks of treatment were tested. SNP data were combined with two independent cohorts in a meta-analysis. A gene-set enrichment analysis (GSEA) was carried out to identify the biological pathways associated with the treatment response.

RESULTS

After genotyping and quality control, 486 450 SNPs were analyzed in 196 Danish patients with moderate to severe RA treated with infliximab (n=142), etanercept (n=12), and adalimumab (n=42). None of the previously identified SNPs were confirmed in our dataset or in meta-analyses of available studies. Other potential SNPs were identified, but none achieved genome-wide significance. A GSEA identified the transforming growth factor β, TNF, mitogen-activated protein kinase, and mammalian target of rapamycin pathways to have a potential influence on the treatment response.

CONCLUSION

In a genome-wide association study of 196 genetically homogenous Danish patients with RA and in a meta-analysis, we found no SNPs associated with treatment response to TNFα inhibitors. A GSEA suggested that the transforming growth factor β, TNF, mitogen-activated protein kinase, and mammalian target of rapamycin pathways may be associated with treatment response.

Cost effectiveness of different treatment strategies in the treatment of patients with moderate to severe rheumatoid arthritis in china

Background

To analyse the cost-effectiveness of traditional disease-modifying anti-rheumatic drugs (tDMARDs) compared to biological therapies from the perspective of Chinese society.

Methodology/Principal Findings

A mathematical model was developed by incorporating the clinical trial data and Chinese unit costs and treatment sequences from a lifetime perspective. Hypothetical cohorts with moderate to severe RA were simulated. The primary outcome measure–quality-adjusted life years (QALYs)–was derived from disease severity (HAQ scores). Primary analysis included drug costs, monitoring costs, and other costs. Probabilistic and one-way sensitivity analyses were performed. Treatment sequences that included TNF antagonists and rituximab produced a greater number of QALYs than tDMARDs alone or TNF antagonists plus DMARDs. In comparison with tDMARDs, the incremental cost-effectiveness ratios (ICERs) for etanercept, infliximab, and adalimumab without rituximab were $77,357.7, $26,562.4 and $57,838.4 per QALY and $66,422.9, $28,780.6 and $50,937.6 per QALY, for etanercept, infliximab, and adalimumab with rituximab. No biotherapy was cost-effective under the willingness to pay threshold when the threshold was 3 times the per capita GDP of China. When 3 times the per capita GDP of Shanghai used as the threshold, infliximab and rituximab could yield nearly 90% cost-effective simulations in probabilistic sensitivity analysis.

Conclusions/Significance

tDMARD was the most cost-effective option in the Chinese healthcare setting. In some relatively developed regions in China, infliximab and rituximab may be a favorable cost-effective alternative for moderate to severe RA.

Monocyte populations as markers of response to adalimumab plus MTX in rheumatoid arthritis

Introduction

The treatment of rheumatoid arthritis (RA) patients with anti-tumor necrosis factor alpha (TNFα) biological drugs has dramatically improved the prognosis of these patients. However, a third of the treated patients do not respond to this therapy. Thus, the search for biomarkers of clinical response to these agents is currently highly active. Our aim is to analyze the number and distribution of circulating monocytes, and of their CD14^+highCD16^-, CD14^+highCD16⁺ and CD14^+lowCD16⁺ subsets in methotrexate (MTX) non-responder patients with RA, and to determine their value in predicting the clinical response to adalimumab plus MTX treatment.

Methods

This prospective work investigated the number of circulating monocytes, and of their CD14^+highCD16^-, CD14^+highCD16⁺ and CD14^+lowCD16⁺ subsets, in 35 MTX non-responder patients with RA before and after three and six months of anti-TNFα treatment using multiparametric flow cytometry. The number of circulating monocytes in an age- and sex-matched healthy population was monitored as a control.

Results

Non-responder patients with RA show an increased number of monocytes and of their CD14^+highCD16^-, CD14^+highCD16⁺ and CD14^+lowCD16⁺ subsets after three months of adalimumab plus MTX treatment that remained significantly increased at six months. In contrast, significant normalization of the numbers of circulating monocytes was found in responders at three months of adalimumab plus MTX treatment that lasts up to six months. CX3CR1 expression is increased in monocytes in non-responders. At three months of anti-TNFα treatment the number of circulating monocytes and their subsets was associated with at least 80% sensitivity, 84% specificity and an 86% positive predictive value (PPV) in terms of discriminating between eventual early responders and non-responders.

Conclusions

The absolute number of circulating monocytes and of their CD14^+highCD16^-, CD14^+highCD16⁺ and CD14^+lowCD16⁺ subsets at three months of adalimumab plus MTX treatment, have a predictive value (with high specificity and sensitivity) in terms of the clinical response after six months of anti-TNFα treatment in patients with RA.

Biologic treatments in Sjögren's syndrome

Primary Sjögren's Syndrome (pSS) is characterized by focal lymphocytic infiltration of secretory exocrine glands associated with severe dryness of eyes and mouth in particular. Systemic features such as disabling fatigue, cutaneous vasculitis, lung, neurological, haematological or other systemic involvement also occur. Conventional immunosuppressive therapies such as corticosteroids or disease-modifying drugs, have been used in some patients with these systemic features with variable benefit. Current therapy for dryness is principally symptomatic although medications to stimulate residual glandular secretion can be helpful for appropriate individuals. As the pathogenesis of the condition becomes better understood, particularly, in recent years, the role of systemic B-cell activation, biologic therapies specifically targeted against molecules involved in disease pathogenesis represent a more targeted approach to therapeutic intervention. The greatest experience in pSS is with rituximab, an anti-CD20 (expressed on a subset of B-cells) monoclonal antibody already in use for the treatment of some B-cell lymphomas and rheumatoid arthritis. Randomised placebo-controlled studies in pSS are currently underway. This review discusses the rationale for using biologic therapies in pSS, the current data on rituximab and the potential use of other biologic therapies in pSS in the future.

Preclinical efficacy of sodium narcistatin to reduce inflammation and joint destruction in rats with adjuvant-induced arthritis

Current therapies for the treatment of rheumatoid arthritis (RA) do not work for all patients, can lose efficacy over time, and can have significant side effects. The discovery of new, effective therapies for RA remains an unmet medical need. The Amaryllidaceae isocarbostyril narciclasine was previously shown to prophylactically reduce paw swelling in rats with adjuvant-induced arthritis (AA). In this study, the efficacy of sodium narcistatin (SNS), a water-soluble cyclic phosphate pro-drug of narciclasine, was assessed in AA rats for anti-inflammatory and bone-sparing properties after disease onset. AA rats were given daily intraperitoneal injections of SNS (1.75, 3.5, or 5 mg/kg/day, in 500 μl sterile endotoxin-free saline) or saline from disease onset through severe disease stages. Footpad widths and radiographic scoring were used as indicators of inflammation and joint destruction, respectively. Ex vivo cytokine production by peripheral blood mononuclear cells (PMBC), splenocytes, and draining lymph node (DLN) cells were determined using ELISAs. SNS treatment dose-dependently reduced joint inflammation (~70%) and bone loss (~50%) compared with AA controls. SNS treatment also reduced spleen weight (without affecting body weight), pro-inflammatory cytokine production by PMBC, splenocytes, and DLN cells, and site-dependently altered T-helper (Th)1-/Th2-type and anti-inflammatory cytokine profiles. SNS dramatically reduces inflammation and has bone-sparing properties, possibly by reducing immune cell pro-inflammatory cytokine production. Our findings support the development of SNS as a therapeutic for RA.

Interleukin-1β stimulates stromal-derived factor-1α expression in human subacromial bursa

Chemokines produced by synoviocytes of the subacromial bursa are up-regulated in subacromial bursitis and rotator cuff disease. We hypothesized that SDF-1α production in bursal synoviocytes may be induced by local cytokines such as interleukin IL-1β and IL-6. Subacromial bursa specimens were obtained from patients undergoing shoulder surgery. Bursal specimens were stained with anti-human antibodies to IL-1, IL-6, and SDF-1α by immunohistochemistry and compared to normal and rheumatoid controls. Bursal cells were also isolated from specimens and cultured. Early passaged cells were then treated with cytokines (IL-1β and IL-6) and SDF-1α expression was measured by ELISA and RT-PCR. SDF-1α, IL-1β, and IL-6 were expressed at high levels in bursitis specimens from human subacromial bursa compared to normal controls. In cultured bursal synoviocytes, there was a dose-dependent increase in SDF-1α production in the supernatants of cells treated with IL-1β. SDF-1α mRNA expression was also increased in bursal cells treated with IL-1β. IL-6 caused a minimal but not statistically significant increase in SDF-1α expression. SDF-1α, IL-1β, and IL-6 are expressed in the inflamed human subacromial bursal tissues in patients with subacromial bursitis. In cultured bursal synoviocytes, SDF-1α gene expression and protein production are stimulated by IL-1β. IL-1β produced by bursal syvoviocytes and inflammatory cells in the human subacromial bursa is an important signal in the inflammatory response that occurs in subacromial bursitis and rotator cuff disease.

Baseline tumour necrosis factor alpha levels predict the necessity for dose escalation of infliximab therapy in patients with rheumatoid arthritis

OBJECTIVES

To investigate the possible role of baseline plasma tumour necrosis factor alpha levels (baseline-TNF) on the clinical response to infliximab in patients with rheumatoid arthritis (RA).

METHODS

Patients with RA refractory to methotrexate received 3, 6, or 10 mg/kg of infliximab every 8 weeks, in a randomised, double-blind manner: the RISING study. Clinical response (disease activity score in 28 joints based on C-reactive protein or American College of Rheumatology core set) at week 54 and serum infliximab levels were compared in three patient groups with low, intermediate, or high baseline-TNF (TNF-low, TNF-int, or TNF-high).

RESULTS

In TNF-low patients, the clinical response to different doses of infliximab was comparable, whereas TNF-int patients exhibited a dose-dependent trend. In contrast, TNF-high patients (approximately 13% of the total patients) had a clinical response to 10 mg/kg significantly better than the response to 3 and 6 mg/kg of infliximab. In TNF-high patients, the median trough serum levels of infliximab were below the detection limit (<0.1 μg/ml) at 3 and 6 mg/kg but were greater than 2 μg/ml at 10 mg/kg, whereas the levels were approximately 1 μg/ml for each dosage group in TNF-low patients.

CONCLUSION

In patients with RA, baseline-TNF is significantly associated with the clinical response to infliximab in patients with a high baseline-TNF. A higher dose of infliximab may be necessary in these patients, whereas lower doses of infliximab are sufficient for those with a low baseline-TNF. Baseline-TNF may be a useful measure for personalising the treatment of RA using infliximab.

Reactivation of hepatitis B virus infection after cytotoxic chemotherapy or immunosuppressive therapy

Reactivation of hepatitis B is defined as the recurrence or an abrupt rise in hepatitis B virus (HBV) replication, often accompanied by an increase in serum transaminase levels, and both events occurring in a patient with a previous inactive hepatitis B infection. This reactivation can occur in situations in which the ratio of HBV replication and immune response is altered. It can happen during the treatment of hemato-oncological malignancies with chemotherapy and in immunosuppression of autoimmune diseases. Clinical manifestations of hepatitis B reactivation are variable and can range from asymptomatic to acute hepatitis, which are sometimes serious and result in acute liver failure with risk of death, and usually occur in the periods between cycles or at the end of chemotherapy. Immunosuppressive drugs such as corticosteroids or azathioprine can induce HBV reactivation in patients carrying hepatitis B virus surface antigen (HBsAg) or anti-HBc, but much less frequently than chemotherapy treatments. The tumor necrosis factor α inhibitors infliximab, etanercept and adalimumab may cause reactivation of hepatitis B, and the overall frequency with infliximab may be similar (50%-66%) to that caused by chemotherapy. Baseline HBV serology is recommended for all patients receiving chemotherapy and immunosuppressive drugs, and HBsAg positive patients should receive anti-HBV prophylaxis to decrease virus reactivation and death rates.

Nucleic acid-stimulated antigen-presenting cells trigger T cells to induce disease in a rat transfer model of inflammatory arthritis

Autoimmune responses to heterogeneous nuclear ribonucleproteins (hnRNP) occur in many systemic autoimmune diseases, particularly in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus. In RA, humoral and/or cellular autoimmunity to hnRNP-A2/B1 is the most prominent anti-nuclear reactivity, being detectable in more than 50% of patients. However, its pathogenic role has not been fully elucidated yet. Here, we report that splenocytes from rats with pristane-induced arthritis transfer disease after in vitro restimulation with hnRNP-A/B antigens. Remarkably, disease transfer can be blocked by nuclease treatment of hnRNPs and is also achieved with splenocytes stimulated with hnRNP-A/B associated DNA or RNA oligonucleotides (ON) alone. Induction of proinflammatory cytokines in splenocytes stimulated with hnRNP-A/Bs or ONs involves Toll-like receptors (TLR) 7 and 9 but not TLR3. Furthermore, although T cells are the main mediators of disease transfer they require restimulation with TLR-activated antigen-presenting cells such as macrophages in order to become arthritogenic. Thus, the autoantigenic properties of hnRNPs appear to be mediated by their associated nucleic acids binding to TLR7 and 9. Our data explain the specific selection of hnRNP-A2/B1 as autoantigen in RA and reveal the requirement of interaction between innate and adaptive immunity to initiate and drive inflammation in autoimmune arthritis.

Getting arthritis gene therapy into the clinic

Gene transfer technologies enable the controlled, targeted and sustained expression of gene products at precise anatomical locations, such as the joint. In this way, they offer the potential for more-effective, less-expensive treatments of joint diseases with fewer extra-articular adverse effects. A large body of preclinical data confirms the utility of intra-articular gene therapy in animal models of rheumatoid arthritis and osteoarthritis. However, relatively few clinical trials have been conducted, only one of which has completed phase II. This article summarizes the status in 2010 of the clinical development of gene therapy for arthritis, identifies certain constraints to progress and suggests possible solutions.

Rheumatoid arthritis progression mediated by activated synovial fibroblasts

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by synovial hyperplasia and progressive joint destruction. Rheumatoid arthritis synovial fibroblasts (RASFs) are leading cells in joint erosion and contribute actively to inflammation. RASFs show an activated phenotype that is independent of the inflammatory environment and requires the combination of several factors. Although new aspects regarding RASF activation via matrix degradation products, epigenetic modifications, inflammatory factors, Toll-like receptor (TLR) activation and others have recently been uncovered, the primary pathophysiological processes in early arthritis leading to permanent activation are mostly unknown. Here, we review new findings regarding RASF activation and their altered behavior that contribute to matrix destruction and inflammation as well as their potential to spread RA.