Biologic therapies in rheumatology: lessons learned, future directions

Wound healing potential and anti-inflammatory action of extracts and compounds of Myrciaria plinioides D. Legrand leaves

Wounds or chronic injuries are associated with high medical costs so, develop healing-oriented drugs is a challenge for modern medicine. The identification of new therapeutic alternatives focuses on the use of natural products. Therefore, the main goal of this study was to evaluate the healing potential and anti-inflammatory mechanism of action of extracts and the main compounds derived from Myrciaria plinioides D. Legrand leaves. The antimicrobial activity of leaf extracts was analyzed. Cell viability, cytotoxicity and genotoxicity of plant extracts and compounds were also assessed. Release of pro- and anti-inflammatory cytokines and TGF-β by ELISA, and protein expression was determined by Western Blot. The cell migration and cell proliferation of ethanol and aqueous leaf extracts and p-coumaric acid, quercetin and caffeic acid compounds were also evaluated. The aqueous extract exhibited antibacterial activity and, after determining the safety concentrations in three assays, we showed that this extract induced p38-α MAPK phosphorylation and the same extract and the p-coumaric acid decreased COX-2 and caspase-3, -8 expression, as well as reduced the TNF-α release and stimulated the IL-10 in RAW 264.7 cells. In L929 cells, the extract and p-coumaric acid induced TGF-β release, besides increasing the process of cell migration and proliferation. These results suggested that the healing properties of Myrciaria plinioides aqueous extract can be associated to the presence of phenolic compounds, especially p-coumaric acid, and/or glycosylated metabolites.

Engineering antigen-presenting cells for immunotherapy of autoimmunity

Autoimmune diseases are burdensome conditions that affect a significant fraction of the global population. The hallmark of autoimmune disease is a host's immune system being licensed to attack its tissues based on specific antigens. There are no cures for autoimmune diseases. The current clinical standard for treating autoimmune diseases is the administration of immunosuppressants, which weaken the immune system and reduce auto-inflammatory responses. However, people living with autoimmune diseases are subject to toxicity, fail to mount a sufficient immune response to protect against pathogens, and are more likely to develop infections. Therefore, there is a concerted effort to develop more effective means of targeting immunomodulatory therapies to antigen-presenting cells, which are involved in modulating the immune responses to specific antigens. In this review, we highlight approaches that are currently in development to target antigen-presenting cells and improve therapeutic outcomes in autoimmune diseases.

Comprehensive insights into rheumatoid arthritis: Pathophysiology, current therapies and herbal alternatives for effective disease management

Rheumatoid arthritis is a chronic autoimmune inflammatory disease characterized by immune response overexpression, causing pain and swelling in the synovial joints. This condition is caused by auto-reactive antibodies that attack self-antigens due to their incapacity to distinguish between self and foreign molecules. Dysregulated activity within numerous signalling and immunological pathways supports the disease's development and progression, elevating its complexity. While current treatments provide some alleviation, their effectiveness is accompanied by a variety of adverse effects that are inherent in conventional medications. As a result, there is a deep-rooted necessity to investigate alternate therapeutic strategies capable of neutralizing these disadvantages. Medicinal herbs display a variety of potent bioactive phytochemicals that are effective in the complementary management of disease, thus generating an enormous potency for the researchers to delve deep into the development of novel phytomedicine against autoimmune diseases, although additional evidence and understanding are required in terms of their efficacy and pharmacodynamic mechanisms. This literature-based review highlights the dysregulation of immune tolerance in rheumatoid arthritis, analyses the pathophysiology, elucidates relevant signalling pathways involved, evaluates present and future therapy options and underscores the therapeutic attributes of a diverse array of medicinal herbs in addressing this severe disease.

Cytokine-directed cellular cross-talk imprints synovial pathotypes in rheumatoid arthritis

INTRODUCTION

Structural reorganisation of the synovium with expansion of fibroblast-like synoviocytes (FLS) and influx of immune cells is a hallmark of rheumatoid arthritis (RA). Activated FLS are increasingly recognised as a critical component driving synovial tissue remodelling by interacting with immune cells resulting in distinct synovial pathotypes of RA.

METHODS

Automated high-content fluorescence microscopy of co-cultured cytokine-activated FLS and autologous peripheral CD4+ T cells from patients with RA was established to quantify cell-cell interactions. Phenotypic profiling of cytokine-treated FLS and co-cultured T cells was done by flow cytometry and RNA-Seq, which were integrated with publicly available transcriptomic data from patients with different histological synovial pathotypes. Computational prediction and knock-down experiments were performed in FLS to identify adhesion molecules for cell-cell interaction.

RESULTS

Cytokine stimulation, especially with TNF-α, led to enhanced FLS-T cell interaction resulting in cell-cell contact-dependent activation, proliferation and differentiation of T cells. Signatures of cytokine-activated FLS were significantly enriched in RA synovial tissues defined as lymphoid-rich or leucocyte-rich pathotypes, with the most prominent effects for TNF-α. FLS cytokine signatures correlated with the number of infiltrating CD4+ T cells in synovial tissue of patients with RA. Ligand-receptor pair interaction analysis identified ICAM1 on FLS as an important mediator in TNF-mediated FLS-T cell interaction. Both, ICAM1 and its receptors were overexpressed in TNF-treated FLS and co-cultured T cells. Knock-down of ICAM1 in FLS resulted in reduced TNF-mediated FLS-T cell interaction.

CONCLUSION

Our study highlights the role of cytokine-activated FLS in orchestrating inflammation-associated synovial pathotypes providing novel insights into disease mechanisms of RA.

Systemic immune-inflammation index and other inflammatory parameters in patients receiving biological or targeted synthetic DMARDs for inflammatory rheumatic disease

Objective: To investigate the short – and long-term dynamics in inflammation markers [systemic immune-inflammation index (SII), neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and lymphocyte/ monocyte ratio (LMR)] before and after biological disease-modifying antirheumatic drugs (bDMARD) or targeted synthetic DMARD (tsDMARD) treatment. Patients and Methods: wo hundred twenty-six patients (115 women, 47±13.8 years) were included. Age, gender, disease duration, and treatments were recorded retrospectively. Complete blood counts including neutrophil, lymphocyte, platelet, monocyte and acute phase reactants were noted at the visit before the biological treatment, at the 3rd month, 6th month, and the last visit on medication. SII, NLR, PLR and LMR were calculated, and their dynamics over time were compared. Results: Significant changes were observed over time in all parameters reflecting inflammation (SII, NLR, PLR, LMR, ESR, and CRP) (p

Switching Between Adalimumab Reference Product and BI 695501 in Patients with Chronic Plaque Psoriasis (VOLTAIRE-X): A Randomized Controlled Trial

BACKGROUND

BI 695501 is an FDA-approved biosimilar to adalimumab reference product (RP). VOLTAIRE-X was a randomized clinical trial to assess outcomes with a biosimilar monoclonal antibody in line with the FDA requirements for designation as an 'interchangeable' biosimilar.

OBJECTIVE

The aim of this study was to assess whether multiple switches between adalimumab RP and BI 695501 lead to equivalent pharmacokinetics and a similar safety and immunogenicity profile compared with continuous adalimumab RP.

METHODS

We conducted a phase III, double-blind, randomized controlled trial between July 19, 2017, and April 16, 2019. There were 49 investigational sites across Europe and North America. Of 323 screened patients with moderate-to-severe chronic plaque psoriasis, 259 were treated with adalimumab RP during the run-in period. Of these, 118 and 120 were randomized to the continuous or switching arms, respectively. Interventions consisted of a run-in period with adalimumab RP 80 mg subcutaneously (SC) on Day 1, then 40 mg SC every other week (EOW) Weeks 2-12. Patients were then randomized to receive adalimumab RP 40 mg EOW Weeks 14-48 (continuous arm) or BI 695501 40 mg Weeks 14 and 16, adalimumab RP 40 mg Weeks 18 and 20, and BI 695501 40 mg EOW Weeks 22 to 48 (switching arm); all interventions were given SC. Primary endpoints were pharmacokinetics parameters, area under the plasma concentration-time curve (AUCτ,30-32) and maximum observed drug plasma concentration (Cmax,30-32), measured after the third switch during the Week 30-32 dosing interval.

RESULTS

238 patients (mean [standard deviation] age 44.9 [13.8]; 66.0% male) were treated in the switching (n = 118) or continuous arms (n = 120). Adjusted mean Cmax,30-32 was 7.08 and 7.00 μg/mL in the switching and continuous treatment arms, respectively; adjusted mean AUCτ,30-32 was 2025.8 and 1925.9 μg h/mL. Point estimate for mean ratio for AUCτ,30-32 was 105.2% (90.2% confidence interval [CI] 96.6-114.6), and 101.1% (90.2% CI 93.3-109.7) for Cmax,30-32. Both CIs were within a predefined bioequivalence range of 80.0-125.0%. Treatment-emergent adverse events led to discontinuation in 0.8% and 1.7% of patients in the switching and continuous treatment arms, and Psoriasis Area and Severity Index (PASI) scores were highly similar in the two arms across the entire trial period.

CONCLUSIONS

Pharmacokinetic equivalence was demonstrated, with highly similar efficacy and immunogenicity, and comparable safety observed in patients with chronic plaque psoriasis who received either adalimumab RP continuously or who switched between adalimumab RP and BI 695501.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03210259 (registered July 2017); Eudract.ema.europa.eu: 2016-002254-20.

Inflammatory Cytokine-Neutralizing Antibody Treatment Prevented Increases in Follicular Helper T Cells and Follicular Regulatory T Cells in a Mouse Model of Arthritis

Background

Follicular T helper (TFH) and follicular regulatory T (TFR) cells play important roles in humoral immunity. Nevertheless, their significance in rheumatoid arthritis (RA) pathogenesis has not been fully elucidated. As an important treatment strategy, the effect of inflammatory factor-neutralizing antibodies on TFH and TFR in RA remains unclear.

Methods

We used the collagen-induced arthritis (CIA) mouse model to illustrate the quantity and functional changes in TFH and TFR cells. The changes of plasmablast, TFH and TFR cells in the spleen and peripheral blood of CIA mice were analyzed by flow cytometry. The levels of TFH and TFR and their functional subsets in the spleen after anti-inflammatory antibody treatment were analyzed and compared. The functional changes of TFH and TFR in CIA mice before and after treatment were detected by in vitro culture experiments.

Results

Plasmablast levels were increased in CIA spleen and peripheral blood and both TFH and TFR cell levels were upregulated. TFH and TFR cells were decreased significantly after the anti-inflammatory antibody treatment. TIGIT⁺ and TIGIT⁺CD226⁻ TFH cells in CIA mouse spleen were elevated and PD-1 and ICOS expression on spleen TFH and TFR cells was increased. Both the ability of TFH cells to secrete IL-21 and aid B cells and the ability of TFR cells to secrete IL-10 and inhibit TFH cells were enhanced in the CIA mice. After antibody treatment, the cell subsets and functions were recovered.

Conclusion

Germinal center TFH and TFR cells were increased and their functions were enhanced. With inflammatory factor-neutralizing antibody treatment, TFH and TFR subsets and their functions returned to normal. These findings provide important information on the dynamics of humoral immune-related cell subsets in RA and the effects of treatment on them.

Cytokine changes in cerebrospinal fluid and plasma after emergency orthopaedic surgery

Neuroinflammation after surgery and its contribution to peri-operative neurocognitive disorders (PND) is not well understood. Studying the association between central and peripheral cytokines and neuroinflammation is a prelude to the development of treatments for PND. Here, we investigate the hypotheses that there is a greater cytokine response in cerebrospinal fluid (CSF) than plasma after orthopaedic surgery, and that plasma cytokine levels are directly related to CSF cytokine levels, indicating that plasma cytokine levels may have potential as biomarkers of neuroinflammation. Patients admitted with a fractured neck of femur were invited to participate in this study. Participants had a spinal catheter inserted just prior to induction of anaesthesia. Samples of blood and CSF were taken before, immediately after, and on the first day following emergency surgery. The catheter was then removed. Samples were analysed for the presence of ten cytokines by immunoassay. A spinal catheter was successfully inserted in 11 participants during the 18-month study period. Five plasma cytokines (IL-4, IL-6, IL-10, IL-12p70 and IL-13) rose significantly following surgery, whereas all ten CSF cytokines rose significantly (IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, IFN-γ and TNF-α) (adjusted-p < 0.05). Central (CSF) cytokine levels were consistently higher than their peripheral (plasma) counterparts after surgery, with some patients having a particularly marked neuroinflammatory response. The greatest increases occurred in IL-8 in CSF and IL-6 in plasma. There were significant, strong positive correlations between several of the measured cytokines in the CSF after surgery, but far fewer in plasma. There was no significant correlation between cytokine levels in the plasma and CSF at each of the three time points. To our knowledge, this is the first study to analyse paired samples of plasma and CSF for cytokine levels before and after emergency orthopaedic surgery. This study demonstrates that following surgery for a fractured neck of femur, there is a far greater rise in cytokines in the CSF compared to plasma. The lack of correlation between peripheral and central cytokines suggests measurement of peripheral cytokines are not necessarily related to which patients may have a large neuroinflammatory response.

Tumor Necrosis Factor Alpha -308G/A Gene Polymorphisms Combined with Neutrophil-to-Lymphocyte and Platelet-to-Lymphocyte Ratio Predicts the Efficacy and Safety of Anti-TNF-α Therapy in Patients with Ankylosing Spondylitis, Rheumatoid Arthritis, and Psoriasis Arthritis

Background: TNF-α has been reported to be closely associated with autoimmune inflammatory diseases. This study aims to investigate the role of TNF-α -308(rs1800629) G/A gene polymorphisms as well as neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in predicting the efficacy and safety of TNF inhibitors (TNFi) in patients with ankylosing spondylitis (AS), rheumatoid arthritis (RA), and psoriasis arthritis (PsA).

Methods: A total of 515 subjects (181 AS, 144 RA, 48 PsA, 10 hyperbilirubinemia, 10 hyperlipidemia and 122 healthy control) were recruited in this study. The accuracy of RT-PCR methods for identifying individual TNF-α -308 genotypes was assessed using sequencing as the gold standard. Baseline NLR and PLR of patients with AS, RA and PsA and healthy controls (HC) were calculated and compared. Meanwhile, differences between responders and non-responders to TNFi treatment as well as between individuals with and without adverse effects (AE) among responders were compared.

Results: The RT-PCR method is stable and reliable for TNF-α -308G/A gene polymorphism analysis, independent of sample status. The GG genotype was overwhelmingly represented, with relatively few GA genotype, whilst the AA genotype was not detected in this study. There was no observed association between TNF-α-308G/A polymorphism and susceptibility in AS, RA or PsA patients. Patients with AS, RA, and PsA had a higher NLR, compared to the HC group. Apart from PsA patients, AS and RA patients had a higher PLR, compared to the HC group. NLR was positively correlated with PLR. Furthermore, a lack of response was more frequently observed in AS and RA patients that carrying the GA genotype than the GG genotype. AS and RA patients with AE had higher NLR and PLR, compared with the non-AE group.

Conclusion: Our study preliminarily shown that combining TNF-α -308G/A polymorphisms with NLR and PLR can predict the responsiveness and safety of anti-TNF therapy in patients with AS or RA.

Lipid metabolism in autoimmune rheumatic disease: implications for modern and conventional therapies

Suppressing inflammation has been the primary focus of therapies in autoimmune rheumatic diseases (AIRDs), including rheumatoid arthritis and systemic lupus erythematosus. However, conventional therapies with low target specificity can have effects on cell metabolism that are less predictable. A key example is lipid metabolism; current therapies can improve or exacerbate dyslipidemia. Many conventional drugs also require in vivo metabolism for their conversion into therapeutically beneficial products; however, drug metabolism often involves the additional formation of toxic by-products, and rates of drug metabolism can be heterogeneous between patients. New therapeutic technologies and research have highlighted alternative metabolic pathways that can be more specifically targeted to reduce inflammation but also to prevent undesirable off-target metabolic consequences of conventional antiinflammatory therapies. This Review highlights the role of lipid metabolism in inflammation and in the mechanisms of action of AIRD therapeutics. Opportunities for cotherapies targeting lipid metabolism that could reduce immunometabolic complications and potential increased cardiovascular disease risk in patients with AIRDs are discussed.

Identification of Novel Modalities Through Bibliometric Analysis for Timely Development of Regulatory Guidance: A Case Study of T Cell Immunity

Background: The mission of medicines regulatory agencies is to ensure the timely access of innovative products for patients to improve public health. Thus, regulators should foresee evolving technologies and build expertise prior to reviewing innovative products. Novel modalities and new classes of therapeutics in biological or cell-based products represent a regulatory challenge because of knowledge gaps, as exemplified by the unexpected cytokine release syndrome in the first-in-human clinical trial of the CD28 super-agonist. Meanwhile, recent treatments harnessing T cell co-signaling pathways provide an opportunity for investigation. Therefore, this study aimed to systematically identify and evaluate novel modalities for T cell immunity to assess the need for regulatory guidance. Methods: A PubMed search was carried out using the query, "immun* AND t lymph*" to select publications. Subsequently, a citation network was created, followed by clustering and text mining to identify the modalities and classes of therapeutics under development. Results and Discussion: Analysis of the top 20 clusters revealed research domains characterized by keywords such as immune checkpoint antibody, chimeric antigen receptor (CAR)-T cells, microbiota, exosome, regulatory T cells, unconventional T cells, and vaccines. After reviewing the pharmacological concepts, clinical trial information, and available guidance, we presented a perspective on the future development of guidance for these domains. Conclusion: Bibliometric analyses identified a set of innovative modalities targeted for drug development with which regulatory guidance is going to catch up. This strategy could help in the successful development of upcoming modalities to ensure readiness for clinical application as part of horizon scanning.

Changes in the use patterns of bDMARDs in patients with rheumatic diseases over the past 13 years

The better understanding of the safety of biologic DMARDs (bDMARDs), as well as the emergence of new bDMARDs against different therapeutic targets and biosimilars have likely influenced the use patterns of these compounds over time. The aim of this study is to assess changes in demographic characteristics, disease activity and treatment patterns in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), or ankylosing spondylitis (AS) who started a first- or second-line biologic between 2007 and mid-2020. Patients diagnosed with RA, PsA or AS included in the BIOBADASER registry from January 2007 to July 2020 were included. According to the start date of a first- or second-line biologic therapy, patients were stratified into four time periods: 2007-2009; 2010-2013; 2014-2017; 2018-2020 and analyzed cross-sectionally in each period. Demographic and clinical variables, as well as the type of biologic used, were assessed. Generalized linear models were applied to study the evolution of the variables of interest over time periods, the diagnosis, and the interactions between them. A total of 4543 patients initiated a first biologic during the entire time frame of the study. Over the four time periods, disease evolution at the time of biologic initiation (p < 0.001), disease activity (p < 0.001), retention rate (p < 0.001) and the use of tumor necrosis factor inhibitors as a first-line treatment (p < 0.001) showed a significant tendency to decrease. Conversely, comorbidities, as assessed by the Charlson index (p < 0.001), and the percentage of patients using bDMARDs in monotherapy (p < 0.001), and corticosteroids (p < 0.001) tended to increase over time. Over the entire period of the study's analysis, 3289 patients started a second biologic. The following trends were observed: decreased DAS28 at switching (p < 0.001), lower retention rates (p = 0.004), and incremental changes to the therapeutic target between the first and second biologic (p < 0.001). From 2007 until now rheumatic patients who started a biologic were older, exhibited less clinical activity, presented more comorbidities, and switched to a different biologic more frequently and earlier.

Biomarker identification and pathway analysis of rheumatoid arthritis based on metabolomics in combination with ingenuity pathway analysis

Rheumatoid arthritis (RA) is a common autoimmune and inflammatory disease worldwide, but understanding its pathogenesis is still limited. In this study, plasma untargeted metabolomics of a discovery cohort and targeted analysis of a verification cohort were performed by gas chromatograph mass spectrometry (GC/MS). Univariate and multivariate statistical analysis were utilized to reveal differential metabolites, followed by the construction of biomarker panel through random forest (RF) algorithm. The pathways involved in RA were enriched by differential metabolites using Ingenuity Pathway Analysis (IPA) suite. Untargeted metabolomics revealed eighteen significantly altered metabolites in RA. Among these metabolites, a three-metabolite marker panel consisting of L-cysteine, citric acid and L-glutamine was constructed, using random forest algorithm that could predict RA with high accuracy, sensitivity and specificity based on a multivariate exploratory receiver operator characteristic (ROC) curve analysis. The panel was further validated by support vector machine (SVM) and partial least squares discriminant analysis (PLS-DA) algorithms, and also verified with targeted metabolomics using a verification cohort. Additionally, the dysregulated taurine biosynthesis pathway in RA was revealed by an integrated analysis of metabolomics and transcriptomics. Our findings in this study not only provided a mechanism underlying RA pathogenesis, but also offered alternative therapeutic targets for RA.

Activation of the cholinergic antiinflammatory reflex by occipitoatlantal decompression and transcutaneous auricular vagus nerve stimulation

CONTEXT

The parasympathetic-mediated inflammatory reflex inhibits excessive proinflammatory cytokine production. Noninvasive techniques, including occipitoatlantal decompression (OA-D) and transcutaneous auricular vagus nerve stimulation (taVNS), have been demonstrated to increase parasympathetic tone.

OBJECTIVES

To test the hypothesis that OA-D and taVNS increase parasympathetic nervous system activity and inhibit proinflammatory cytokine mobilization and/or production.

METHODS

Healthy adult participants were randomized to receive OA-D (5 min of OA-D followed by 10 min of rest; n=8), taVNS (15 min; n=9), or no intervention (15 min, time control; n=10) on three consecutive days. Before and after these interventions, saliva samples were collected for determination of the cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor α (TNF-α). Arterial blood pressure and the electrocardiogram were recorded for a 30-min baseline, throughout the intervention, and during a 30-min recovery period to derive heart rate and blood pressure variability markers as indices of vagal and sympathetic control.

RESULTS

OA-D and taVNS increased root mean square of successive RR interval differences (RMSSD) and high frequency heart rate variability, which are established markers for parasympathetic modulation of cardiac function. In all three groups, the experimental protocol was associated with a significant increase in salivary cytokine concentrations. However, the increase in IL-1β was significantly less in the taVNS group (+66 ± 13 pg/mL; p<0.05) than in the time control group (+142 ± 24 pg/mL). A similar trend was observed in the taVNS group for TNF-α (+1.7 ± 0.3 pg/mL vs. 4.1 ± 1.3 pg/mL; p<0.10). In the OA-D group baseline IL-6, IL-8, and TNF-α levels on the third study day were significantly lower than on the first study day (IL-6: 2.3 ± 0.4 vs. 3.2 ± 0.6 pg/mL, p<0.05; IL-8: 190 ± 61 vs. 483 ± 125 pg/mL, p <0.05; TNF-α: 1.2 ± 0.3 vs. 2.3 ± 0.4 pg/mL, p<0.05). OA-D decreased mean blood pressure from the first (100 ± 8 mmHg) to the second (92 ± 6 mmHg; p<0.05) and third (93 ± 8 mmHg; p<0.05) study days and reduced low frequency spectral power of systolic blood pressure variability (19 ± 3 mmHg² after OA-D vs. 28 ± 5 mmHg² before OA-D; p<0.05), a marker of sympathetic modulation of vascular tone. OA-D also increased baroreceptor-heart rate reflex sensitivity from the first (13.7 ± 3.0 ms/mmHg) to the second (18.4 ± 4.3 ms/mmHg; p<0.05) and third (16.9 ± 4.2 ms/mmHg; p<0.05) study days.

CONCLUSIONS

Both OA-D and taVNS elicited antiinflammatory responses that were associated with increases in heart rate variability-derived markers for parasympathetic function. These findings suggest that OA-D and taVNS activate the parasympathetic antiinflammatory reflex. Furthermore, an antihypertensive effect was observed with OA-D that may be mediated by reduced sympathetic modulation of vascular tone and/or increased baroreceptor reflex sensitivity.

The Potential for Phospholipids in the Treatment of Airway Inflammation: An Unexplored Solution

Asthma, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF) are major inflammatory respiratory diseases. Current mainstay therapy for asthma, and chronic obstructive pulmonary disease are corticosteroids, which have well-established side effect profiles. Phospholipids (PLs) are ubiquitous, diverse compounds with varying functions such as their structural role incell membrane, energy storage, and cell signaling.Recent advances in understanding PLs role as inflammatory mediators in the body as well as their widespread long-standing use as carrier molecules in drug delivery demonstrate the potential application of phospholipids in modulating inflammatory conditions. This review briefly explains the main mechanisms of inflammation in chronic respiratory diseases, currentanti-inflammatory treatments and areas of unmet need. The structural features, roles of endogenous and exogenous phospholipids, including their use as pharmaceutical excipients are reviewed. Current research on the immunomodulatory properties of PLs and their potentialapplication in inflammatory diseasesis the major section of this review. Considering the roles of PLs as inflammatory mediators and their safety profile established in pharmaceutical formulations, these small molecules demonstrate great potential as candidates in respiratory inflammation. Future studies need to focus on the immunomodulatory properties and the underlying mechanisms of phospholipids in respiratory inflammatory diseases.

Retrospective analyzes of adverse events during biologic agents in children with juvenile idiopathic arthritis from a single center in Turkey

OBJECTIVES

Juvenile idiopathic arthritis is the most common rheumatic disease in childhood. Biologic agents have changed the course of juvenile idiopathic arthritis. However, there are concerns regarding the occurrence of serious adverse events in patients receiving biologic agents. The aim of this study was to evaluate adverse events in children with juvenile idiopathic arthritis receiving biologic agents.

MATERIAL AND METHODS

This retrospective study includes juvenile idiopathic arthritis patients receiving biologic agents. Demographic features and adverse events during biologic agents were collected from medical files. Adverse events that either resulted in death, were life-threatening, required inpatient hospitalization, or resulted in persistent or significant disability/incapacity were considered as serious adverse events.

RESULTS

In total, 162 juvenile idiopathic arthritis patients (55.6% female) receiving biologic agents were enrolled: 101 (62.3%) patients treated with etanercept, 27 (16.7) with tocilizumab, 14 (8.6%) with adalimumab, 15 (9.2%) with anti-interleukin 1 agents (13 canakinumab, 2 anakinra), and 5 (3.1%) with infliximab. 75.9% of the patients received concomitantly disease-modifying anti-rheumatic drugs, and 20.4% received disease-modifying anti-rheumatic drugs plus corticosteroid. The mean age at initiation of the biologic agent was 10.5 ±4.3 years. The mean age at the study enrolment was 12.1 ±4.5 years. The mean follow-up duration was 19.7 ±2.1 months. The most frequent adverse event was upper respiratory tract infections (54.3%) followed by urinary tract infections (21%). Anaphylaxis occurred in 3 patients (1.9%): 2 with tocilizumab and one with infliximab. Macrophage activation syndrome occurred in 1 patient (0.6%) receiving tocilizumab. Lung tuberculosis developed in 2 patients (1.2%) receiving canakinumab. The frequency of serious adverse events in total was 6.7%.

CONCLUSIONS

While the most frequent adverse events during biologic agents was upper respiratory tract infections, the frequency of serious adverse events was 6.7%; therefore, juvenile idiopathic arthritis patients receiving biologic agents should be carefully evaluated for these adverse events in clinical practice.

Immunogenicity of Biosimilars for Rheumatic Diseases, Plaque Psoriasis, and Inflammatory Bowel Disease: A Review from Clinical Trials and Regulatory Documents

The goal of this narrative review was to summarize immunogenicity data of biosimilars or biosimilar candidates for rheumatic diseases, plaque psoriasis, or inflammatory bowel disease (IBD), available in peer-reviewed publications or regulatory documents. PubMed records and regulatory documents were searched for immunogenicity data of TNFα or CD20 inhibitor biosimilars or biosimilar candidates. Data collected included the proportion of patients positive for anti-drug antibodies (ADAbs), proportion with neutralizing antibodies (nAbs) among ADAb-positive patients, ADAb/nAb assay characteristics, cross-reactivity, and the effects of ADAbs on pharmacokinetics, pharmacodynamics, efficacy, and safety. We identified eight biosimilars or biosimilar candidates for adalimumab (BI 695501, SB5, ABP 501, GP2017, PF-06410293, MSB-11022, FKB-327, ZRC-3197) four for etanercept (SB4, GP2015, CHS-0214, LBEC0101), and three each for infliximab (SB2, CT-P13, GP1111) and rituximab (CT-P10, GP2013, PF-05280586) with immunogenicity data. Randomized, head-to-head trials with reference products varied in design and methodology of ADAb/nAb detection. The lowest proportions of ADAb-positive (0–13%) and nAb-positive patients (0–3%) were observed in the trials of etanercept and its biosimilars, and the highest with adalimumab, infliximab, and their biosimilars (ADAbs: ≤ 64%; nAbs: ≤ 100%). The most common method of ADAb detection was electrochemiluminescence, and ADAb positivity was associated with nominally inferior efficacy and safety. Overall, there were no significant immunogenicity differences between biosimilars and reference products. However, there are many discrepancies in assessing and reporting clinical immunogenicity. In conclusion, immunogenicity data of biosimilars or biosimilar candidates for TNFα or CD20 inhibitors were collected in trials that varied in design and procedures for ADAb/nAb detection. In general, immunogenicity parameters of biosimilars are similar to those of their reference products.

Tolerance-inducing medicines in autoimmunity: rheumatology and beyond

Autoimmunity is currently managed with generalised immunosuppression, which is associated with serious side-effects such as infection and cancer. An ideal treatment strategy would be to induce immune tolerance-ie, to reprogramme the immune system to stop recognising the host itself as a threat. Drug-free remission should follow such an intervention, representing a change in the approach to the treatment of autoimmune disease. Tolerance induction is achievable in animal models of autoimmunity but translation to the clinic has been slow. Nonetheless, progress has been made-eg, restoration of therapeutic responsiveness and drug-free remission have been achieved with stem cell transplantation in refractory autoimmunity, and significant delays in onset of type 1 diabetes in individuals at high risk have been achieved following a brief treatment with anti-CD3 monoclonal antibody. In the future, antigen-specific interventions should provide highly targeted, personalised approaches, avoiding generalised immunosuppression entirely. Such trials have already started, using both direct autoantigenic peptide administration, cellular therapies, and other modalities. In this Series paper, we discuss the history of immune tolerance induction with a focus on rheumatological disease while also highlighting essential data from other specialties. We propose key unanswered questions, which will be covered in other papers in this Series.

Lower peripheral helper T cell levels in the synovium are associated with a better response to anti-TNF therapy in rheumatoid arthritis

Background

The mechanisms by which only some rheumatoid arthritis (RA) patients respond favorably to TNF blockade are still poorly characterized. The goal of this study was to identify biological features that explain this differential response using a multilevel transcriptome analysis of the synovial membrane.

Methods

Synovial samples from 11 patients on anti-TNF therapy were obtained by arthroscopy at baseline and week 20. Analysis of the synovial transcriptome was performed at the gene, pathway, and cell-type levels. Newly characterized pathogenic cell types in RA, peripheral helper T cells (T_PH), and CD34-THY1+ fibroblasts were estimated using a cell-type deconvolution approach. T_PH association was validated using immunofluorescence. External validation was performed on an independent dataset.

Results

After multiple-test correction, 16 and 4 genes were differentially expressed at baseline and week 20, respectively. At the pathway level, 86 and 17 biological processes were significantly enriched at baseline and week 20, respectively. Longitudinal expression changes were associated with a drastic decrease of innate immune activity (P < 5e−30), and an activation of the bone and cartilage regeneration processes (P < 5e−10). Cell-type deconvolution revealed a significant association between low T_PH cells at baseline and a better response (P = 0.026). Lower T_PH cells were maintained in good responders up to week 20 (P = 0.032). Immunofluorescent analyses confirmed the accuracy of the cell-type estimation (r² = 0.58, P = 0.005) and an association with response. T_PH association with anti-TNF response was validated in an independent sample of RA patients (P = 0.0040).

Conclusions

A lower abundance in the synovial membrane of the pathogenic T cell type newly associated with RA, peripheral helper T lymphocyte, is associated with a good response to anti-TNF therapy. Major changes in the myeloid cell compartment were also observed in response to therapy. The results of this study could help develop more effective therapies aimed at treating the pathogenic mechanisms in RA that are currently not well targeted by anti-TNF agents.

Expression of NK (CD16+56+) and B cells (CD19) Receptor Molecules as a Reliable Clinical Response Biomarkers of SLE and RA Patients Under the Rituximab Treatment

Introduction

Lately, the use of biological therapy in various autoimmune diseases is increasing. The ideal marker for monitoring the effects of modern therapy is still non-existent.

Aim

To investigate early response biomarkers of SLE and RA patients under the rituximab treatment are in research phase and each new investigations offer new and original useful data.

Material and Methods

Immunophenotyping of cells was carried out by a standard method of sample preparation. We investigated by flow cytometric analyses expression of NK and CD19+ cells at ten SLE and five RA patients before and after treatment with rituximab, in laboratory of Department of Clinical immunology in the Clinical Centre University of Sarajevo.

Results

In both cases, SLE and RA patients, reduced number of CD16+ parameter indicates lower cytotoxic activity of NK cells. Increased number of B cells indicates higher pathological activity leading to severe autoimmune disease allegation.

Conclusion

Determining the proportion of NK and B will be useful diagnostic tool in therapeutic strategy, and also in monitoring of effect of biological therapy.

Disease modifying drugs for rheumatological diseases: a brief history of everything

The rheumatological diseases are a group of chronic, painful, degenerative and debilitating conditions with an increasing prevalence across the globe. The pathogenesis of these disorders is complex, overlapping and not fully understood. As such, it is difficult and time consuming to achieve correct diagnosis and complete remission for an individual patient. In this review we describe the most common forms of inflammatory arthritis and discuss how the management and treatment options for these rheumatic diseases have developed over time. We outline the successes and the limitations of current treatment regimens and discuss the economic burden of the current options. With advancements in understanding of disease mechanisms, we discuss the importance of the biologics revolution in the context of rheumatological disease and how the development of biosimilars and small molecule inhibitors will impact current treatment options in order to alleviate some of the cost burden of biological therapies. The ideal treatment strategy for the future would involve personalized and predictive medicine where by treatments can be tailored to an individual patient's needs in order to achieve fast and successful remission with no adverse events.

The chemokine receptor CCR7 is a promising target for rheumatoid arthritis therapy

The chemokine receptor CCR7 and its ligands CCL19 and CCL21 guide the homing and positioning of dendritic and T cells in lymphoid organs, thereby contributing to several aspects of adaptive immunity and immune tolerance. In the present study, we investigated the role of CCR7 in the pathogenesis of collagen-induced arthritis (CIA). By using a novel anti-human CCR7 antibody and humanized CCR7 mice, we evaluated CCR7 as a target in this autoimmune model of rheumatoid arthritis (RA). Ccr7-deficient mice were completely resistant to CIA and presented severely impaired antibody responses to collagen II (CII). Selective CCR7 expression on dendritic cells restored arthritis severity and anti-CII antibody titers. Prophylactic and therapeutic treatment of humanized CCR7 mice with anti-human CCR7 mAb 8H3-16A12 led to complete resistance to CIA and halted CIA progression, respectively. Our data demonstrate that CCR7 signaling is essential for the induction of CIA and identify CCR7 as a potential therapeutic target in RA.

A Synthetic Cross-Species CD200R1 Agonist Suppresses Inflammatory Immune Responses In Vivo

Functional aptamers displaying agonistic or antagonistic properties are showing great promise as modulators of immune responses. Here, we report the development of a polyethylene glycol-modified (PEGylated) DNA aptamer as a cross-species (murine and human) CD200R1 agonist that modulates inflammatory responses in vivo. Specifically, DNA aptamers were discovered by performing independent SELEX searches on recombinant murine and human CD200R1. Aptamer motifs identified by next generation sequencing (NGS) were subsequently compared, leading to the discovery of motifs common to both targets. The CD200R1 DNA aptamer CCS13 displayed the highest agonistic activity toward CD200R1 in terms of suppressing the induction of cytotoxic T-lymphocytes (CTLs) in both human and murine allogeneic-mixed lymphocyte cultures (allo-MLCs). A 20-kDa polyethylene glycol (PEG) chain was covalently attached to the 5′ end of this aptamer, and the resulting conjugate was shown to block inflammatory responses in murine models of skin graft rejection and house-dust-mite-induced allergic airway inflammation. Importantly, this agonistic aptamer does not suppress CTL induction in 5-day allo-MLCs with responder cells derived from CD200R1^−/− mice, indicating that its mode of action is directly linked to CD200R1 activation. This study suggests that one can derive agonistic DNA aptamers that can be verified as immuno-modulators in murine models with outcomes potentially translatable to the treatment of human conditions.

The comparative immunogenicity of biologic therapy and its clinical relevance in psoriatic arthritis: a systematic review of the literature

INTRODUCTION

Biologic agents have demonstrated efficacy in treating patients with psoriatic arthritis (PsA). Biologic agents also have an intrinsic capacity to induce an immune response in patients that could result in unwanted adverse events and/or treatment failure.

AREAS COVERED

In this systematic literature review, the authors document the incidence of immune responses, primarily anti-drug antibodies (ADA), to the biologic therapeutic agents currently in clinical practice for the treatment of PsA. The authors discuss the importance of these responses with respect to clinical practice.

EXPERT OPINION

Our evaluation of the published literature shows that the immune responses to the various biologic therapeutic agents currently being used to treat PsA are similar to those observed for these agents in other rheumatic diseases. Moreover, similar to observations in other rheumatic diseases, the incidence of ADA formation to biologic agents in patients with PsA is often decreased when patients are given concomitant treatment with disease-modifying anti-rheumatic drugs. These data strongly suggest that the immune response is a characteristic of the biologic agent. Using therapeutic drug monitoring may be an approach to assess the immune response to the agent and to mitigate the potential impact on efficacy and safety, and consequently optimize treatment.

Mucosa-associated lymphoid tissue lymphoma translocation 1 as a novel therapeutic target for rheumatoid arthritis

Emerging evidence suggests that mucosa-associated lymphoid tissue lymphoma translocation 1 (MALT1) is a key regulator of inflammatory diseases; however, the pathological role of MALT1 in rheumatoid arthritis (RA) is not well understood. Consequently, this protein has not been therapeutically targeted for the treatment of RA. MALT1 plays a role in the paracaspase pathway, has proteolytic activity and is involved in the regulation of inflammatory responses. In this study, we found that the MALT1-targeting inhibitory small molecule, MALT1 selective inhibitor 2-chloro-N-[4-[5-(3,4-dichlorophenyl)-3-(2-methoxyethoxy)-1H-1,2,4-triazol-1-yl]phenylacetamide (MI-2) strongly suppresses the differentiation of monocytes into osteoclasts in the absence or presence of the inflammatory cytokine tumour necrosis factor α. Furthermore, MI-2 ameliorates pathologic bone erosion and synovitis in an in vivo mouse model of collagen-induced arthritis. Mechanistically, MI-2 blocked expression of the master osteoclast regulator - nuclear factor of activated T cells 1 (NFATc1) - by inhibiting nuclear factor κB (NF-κB), which is a critical regulator of NFATc1. These findings highlight the important regulatory role of MALT1 in the NF-κB-NFATc1-signalling axis during osteoclastogenesis and suggest that targeting MALT1 is a promising treatment option for rheumatoid arthritis.

Intravenous immunoglobulin: a biological corticosteroid-sparing agent in some autoimmune conditions

Intravenous immunoglobulin (IVIg) is increasingly used for the treatment of autoimmune and systemic inflammatory diseases. This compound is effective in a wide range of clinical conditions other than primary immunodeficiency, including autoimmune diseases, inflammatory disorders, infections, organ transplantation, and possibly supportive therapy for cancer. Systemic corticosteroids remain the gold standard treatment for many autoimmune diseases, but their long-term use is associated with complications in diverse organs and systems. Osteoporosis, osteonecrosis, cardiovascular disease, infections, and cancer have been associated with this treatment. Therefore, physicians are occasionally forced to withdraw the treatment with steroids. Biological agents may represent a good alternative, but in addition to being very expensive, these agents may have serious side effects. This review aimed to cover the major advances in the use of IVIg as a steroid-sparing agent in some relevant autoimmune diseases.

Immunogenicity of Biologics in Chronic Inflammatory Diseases: A Systematic Review

OBJECTIVES

A systematic review was conducted to explore the immunogenicity of biologic agents across inflammatory diseases and its potential impact on efficacy/safety.

METHODS

Literature searches were conducted through November 2016 to identify controlled and observational studies of biologics/biosimilars administered for treatment of rheumatoid arthritis (RA), psoriatic arthritis (PsA), juvenile idiopathic arthritis (JIA), ankylosing spondylitis (AS), non-radiographic axial spondyloarthritis (nr-axSpA), psoriasis (Ps), Crohn's disease, and ulcerative colitis.

RESULTS

Of >21,000 screened publications, 443 were included. Anti-drug antibody (ADAb) rates varied widely among biologics across diseases (and are not directly comparable because of immunoassay heterogeneity); the highest overall rates were reported with infliximab (0-83%), adalimumab (0-54%), and infliximab biosimilar CT-P13 (21-52%), and the lowest with secukinumab (0-1%), ustekinumab (1-11%), etanercept (0-13%), and golimumab (0-19%). Most ADAbs were neutralizing, except those to abatacept and etanercept. ADAb+ versus ADAb- patients had lower rates of clinical response to adalimumab (RA, PsA, JIA, AS, Ps), golimumab (RA), infliximab (RA, PsA, AS, Ps), rituximab (RA), ustekinumab (Ps), and CT-P13 (RA, AS). Higher rates of infusion-related reactions were reported in infliximab- and CT-P13-treated ADAb+ patients. Background immunosuppressives/anti-proliferatives reduced biologic immunogenicity across diseases.

CONCLUSIONS

Based on reviewed reports, biologic/biosimilar immunogenicity differs among agents, with the highest rates observed with infliximab and adalimumab. As ADAb formation in biologic-/biosimilar-treated patients may increase the risk of lost response, the immunogenicity of these agents is an important (albeit not the only) consideration in the treatment decision-making process.

Mithramycin has inhibitory effects on gliostatin and matrix metalloproteinase expression induced by gliostatin in rheumatoid fibroblast-like synoviocytes

OBJECTIVES

Gliostatin (GLS) has angiogenic and arthritogenic activities and enzymatic activity as thymidine phosphorylase. Aberrant GLS production has been observed in the synovial membranes of patients with rheumatoid arthritis (RA). Matrix metalloproteinases (MMPs) are involved in joint destruction. Promoters of GLS and some MMP genes contain Sp1 binding sites. We examined the inhibitory effect of the Sp1 inhibitor mithramycin on GLS-induced GLS and MMP expression in cultured fibroblast-like synoviocytes (FLSs).

METHODS

Synovial tissue samples were obtained from patients with RA. FLSs pretreated with mithramycin were cultured with GLS. The mRNA expression levels of GLS and MMP-1, MMP-2, MMP-3, MMP-9, and MMP-13 were determined using reverse transcription polymerase chain reactions. Protein levels were measured using enzyme immunoassay and gelatin zymography.

RESULTS

GLS upregulated the expression of GLS itself and of MMP-1, MMP-3, MMP-9, and MMP-13, an effect significantly reduced by treatment with mithramycin. GLS and mithramycin had no effect on MMP-2 expression.

CONCLUSIONS

Mithramycin downregulated the increased expression of GLS and MMP-1, MMP-3, MMP-9, and MMP-13 in FLSs treated with GLS. Because GLS plays a pathological role in RA, blocking GLS stimulation using an agent such as mithramycin may be a novel approach to antirheumatic therapy.

An introduction to biosimilar cancer therapeutics: definitions, rationale for development and regulatory requirements

Monoclonal antibodies and other biologic drugs play important roles in the treatment of various hematological malignancies and solid tumors. However, such drugs are intrinsically more expensive to develop than small molecules and their clinical benefits are often accompanied by challenges relating to affordability and access. Patent expiry for ‘originator’ biologics is providing opportunities for a new generation of biosimilar drugs, potentially capable of relieving pressure on healthcare budgets. This article discusses key characteristics of biosimilars, distinguishes them from generics and noncomparable biologics and outlines the robust regulatory requirements that must be followed to establish biosimilarity with a reference product. The path to approval is discussed with reference to the rituximab biosimilar CT-P10, the first licensed monoclonal antibody biosimilar cancer therapeutic.

Room for more IL-6 blockade? Sarilumab for the treatment of rheumatoid arthritis

INTRODUCTION

Rheumatoid arthritis (RA) treatment has been revolutionized by the development of highly efficacious biotherapeutics. However, a significant subset of RA patients has persistently active disease and ongoing erosive joint damage despite the available therapies. Sarilumab targets interleukin-6, one of the main cytokines mediating inflammation in RA. Positive results with sarilumab in RA clinical trials support the licensing application currently under review with the US Food and Drug Administration.

AREAS COVERED

The rationale for IL-6 targeting in RA, the pharmacologic properties of sarilumab, and the clinical trial results are reviewed focusing on the pending application for the RA indication. Comparisons with other IL-6 targeting biologics as well as additional potential therapeutic directions are discussed.

EXPERT OPINION

Sarilumab is a highly active therapeutic in patients with RA. While pharmacologic data demonstrate that sarilumab has a higher affinity than tocilizumab for the target receptor, available clinical results suggest that efficacy and adverse event profiles are similar to this other IL-6 blocker, which is currently approved for the treatment of RA. Whether there are other distinct differences or advantages of sarilumab that will support the approval and successful marketing of this drug, over existing therapies, remains to be determined.

Tregalizumab - A Monoclonal Antibody to Target Regulatory T Cells

Regulatory T cells (Tregs) represent a subpopulation of CD4⁺ T cells, which are essential for the maintenance of immunological tolerance. The absence or dysfunction of Tregs can lead to autoimmunity and allergies. The restoration of functional Tregs and/or Treg cell numbers represents a novel and attractive approach for the treatment of autoimmune diseases, e.g., rheumatoid arthritis (RA). The CD4 cell surface receptor is a target for modulation of T cell function. Monoclonal antibodies (mAbs) against CD4 have previously been tested for the treatment of autoimmune diseases, including RA. Furthermore, in model systems, anti-CD4 antibodies are able to induce tolerance and mediate immunomodulatory effects through a variety of mechanisms. Despite the availability of innovative and effective therapies for RA, many patients still have persistently active disease or experience adverse events that can limit use. A growing body of evidence suggests that Treg modulation could offer a new therapeutic strategy in RA and other autoimmune disorders. Here, we describe tregalizumab (BT-061), which is a novel, non-depleting IgG1 mAb that binds to a unique epitope of CD4. Tregalizumab represents the first humanized anti-CD4 mAb that selectively induces Treg activation.

Overexpression of TLR2 and TLR9 on monocyte subsets of active rheumatoid arthritis patients contributes to enhance responsiveness to TLR agonists

Background

Synovial infiltration of monocytes is commonly associated with inflammation in rheumatoid arthritis (RA). Toll-like receptors (TLRs) are innate sensors that recognize cell debris and microbial components in host, a process contributing to maintain chronic inflammation in RA. We assessed the expression levels of TLR2 and TLR9 in monocyte subsets of active RA patients and characterized their cytokine profiles in response to synthetic and viral TLR2 and TLR9 agonists, including Epstein-Barr virus (EBV) which is suspected to contribute to RA symptoms.

Methods

Prevalence of monocyte subsets CD14⁺⁺ CD16⁻, CD14⁺ CD16⁺ and CD14^low CD16⁺⁺ was evaluated in blood and synovial fluids of active RA patients and levels of TLR2 and TLR9 in monocyte subsets were measured by flow cytometry. Enriched monocytes derived from RA patients and healthy donors were stimulated in vitro with synthetic TLR2 and TLR9 agonists and with EBV particles or viral DNA. Intracellular cytokine profiles were determined in respective monocyte subsets. Finally, the presence of EBV genome was evaluated by real-time PCR in blood and synovial monocytes of RA patients.

Results

Numbers of CD14⁺ CD16⁺ and CD14^low CD16⁺⁺ were found to increase in blood of RA patients compared to healthy controls, while all three subsets were detected in synovial fluids. TLR2 is abundantly expressed on blood and synovial CD14⁺⁺ CD16⁻ and CD14⁺ CD16⁺ monocytes from RA patients. Levels of TLR9 were increased on all three subsets of blood monocytes but markedly enhanced in monocytes isolated from synovial fluids. Compared to healthy controls, CD14⁺⁺ CD16⁻ monocytes of RA patients displayed an enlarged capacity to produce proinflammatory cytokines after stimulation with synthetic TLR2 and TLR9 agonists while both CD14⁺⁺ CD16⁻ and CD14⁺ CD16⁺ monocytes showed increased response to EBV stimulation. The presence of EBV genome was also detected in monocytes and neutrophils of a significant proportion of patients.

Conclusion

Patients with active RA show an increased expression of TLR2 and TLR9 on monocyte subsets and display higher production of inflammatory cytokines in response to TLR agonists. The presence of EBV genome in monocytes and neutrophils reinforces the suspected role of the virus in the exacerbation of RA symptoms.

Applying refinement to the use of mice and rats in rheumatoid arthritis research

Rheumatoid arthritis (RA) is a painful, chronic disorder and there is currently an unmet need for effective therapies that will benefit a wide range of patients. The research and development process for therapies and treatments currently involves in vivo studies, which have the potential to cause discomfort, pain or distress. This Working Group report focuses on identifying causes of suffering within commonly used mouse and rat ‘models’ of RA, describing practical refinements to help reduce suffering and improve welfare without compromising the scientific objectives. The report also discusses other, relevant topics including identifying and minimising sources of variation within in vivo RA studies, the potential to provide pain relief including analgesia, welfare assessment, humane endpoints, reporting standards and the potential to replace animals in RA research.

A key role for Fut1-regulated angiogenesis and ICAM-1 expression in K/BxN arthritis

OBJECTIVES

Angiogenesis contributes to the pathogenesis of rheumatoid arthritis. Fucosyltransferases (Futs) are involved in angiogenesis and tumour growth. Here, we examined the role of Fut1 in angiogenesis and K/BxN serum transfer arthritis.

METHODS

We examined Fut1 expression in human dermal microvascular endothelial cells (HMVECs) by quantitative PCR. We performed a number of angiogenesis assays to determine the role of Fut1 using HMVECs, Fut1 null (Fut1(-/-)), and wild type (wt) endothelial cells (ECs) and mice. K/BxN serum transfer arthritis was performed to determine the contribution of Fut1-mediated angiogenesis in Fut1(-/-) and wt mice. A static adhesion assay was implemented with RAW264.7 (mouse macrophage cell line) and mouse ECs. Quantitative PCR, immunofluorescence and flow cytometry were performed with Fut1(-/-) and wt ECs for adhesion molecule expression.

RESULTS

Tumour necrosis factor-α induced Fut1 mRNA and protein expression in HMVECs. HMVECs transfected with Fut1 antisense oligodeoxynucleotide and Fut1(-/-) ECs formed significantly fewer tubes on Matrigel. Fut1(-/-) mice had reduced angiogenesis in Matrigel plug and sponge granuloma angiogenesis assays compared with wt mice. Fut1(-/-) mice were resistant to K/BxN serum transfer arthritis and had decreased angiogenesis and leucocyte ingress into inflamed joints. Adhesion of RAW264.7 cells to wt mouse ECs was significantly reduced when Fut1 was lacking. Fut1(-/-) ECs had decreased intercellular adhesion molecule-1 (ICAM-1) expression at mRNA and protein levels compared with wt ECs. ICAM-1 was also decreased in Fut1(-/-) arthritic ankle cryosections compared with wt ankles.

CONCLUSIONS

Fut1 plays an important role in regulating angiogenesis and ICAM-1 expression in inflammatory arthritis.

Rehabilitation or the death penalty: autoimmune B cells in the dock

CD20-based monoclonal antibodies have become established as treatments for lymphoma, rheumatoid arthritis, systemic lupus erythematosus, vasculitis and dermatomyositis, with the principle therapeutic mechanism relating to B-cell depletion through effector cell engagement. An article by Brühl et al. in this issue of the European Journal of Immunology [Eur. J. Immunol. 2015. 45: 705-715] reveals a fundamentally distinct mechanism of silencing autoimmune B-cell responses. Rather than B-cell depletion, the authors use anti-CD79b antibodies to induce B-cell tolerance and suppress humoral immune responses against collagen to prevent the development of arthritis in mice. Here we highlight the differences in the mechanisms used by anti-CD20 and anti-CD79b Ab therapy and discuss why depletion of B cells may not be required to treat autoimmune arthritis and other B-cell-associated pathologies.

Biosimilars in psoriasis: what can we expect?

Biosimilars are biotechnologically processed drugs whose amino acid sequence is identical to the original biopharmaceutical. They are of considerable clinical, economical, and health care interest. As patents for biologicals used to treat psoriasis expire, biosimilars will become more and more important within the field of dermatology. The patents for the two top-selling drugs (adalimumab and etanercept) will terminate in the next few years. Applications for biosimilars will presumably be submitted to the EMA and the FDA for all patent-free biologicals. Both regulatory bodies have issued guidelines on the assessment of bioequivalence, as well as the benefits and risks of biosimilars. While the preclinical requirements of the FDA and EMA are largely comparable, the formal requirements for clinical bioequivalence, including clinical efficacy and safety, differ markedly. Therefore, from a medical and health care perspective before biosimilars enter the market, specific evidence-based regulatory conditions need to be created and fulfilled. Only then biosimilars can be a less expensive option for a large number of patients, providing them with substances of the same value. Adequate, unequivocal proof of their bioequivalence, quality, and related patient safety should have priority over any ostensible economic benefits.

Rheumatoid arthritis: from palliation to remission in two decades

The last 20 years have seen a transformation in the landscape of rheumatoid arthritis, which has changed from being a life limiting condition to a chronic but often remitting illness. The importance of early disease control, the better use of existing therapies, and the development of new therapies have all been key to this success. The future of therapy now lies in the identification of stratifying biomarkers, to allow more rational delivery of treatment. The ultimate goal remains the reintroduction of immune tolerance to potentially achieve a 'cure.'