A randomized, phase II study of sequential belimumab and rituximab in primary Sjögren's syndrome.

BACKGROUNDPrimary Sjögren's syndrome (pSS) is characterized by B cell hyperactivity and elevated B-lymphocyte stimulator (BLyS). Anti-BLyS treatment (e.g., belimumab) increases peripheral memory B cells; decreases naive, activated, and plasma B cell subsets; and increases stringency on B cell selection during reconstitution. Anti-CD20 therapeutics (e.g., rituximab) bind and deplete CD20-expressing B cells in circulation but are less effective in depleting tissue-resident CD20+ B cells. Combined, these 2 mechanisms may achieve synergistic effects.METHODSThis 68-week, phase II, double-blind study (GSK study 201842) randomized 86 adult patients with active pSS to 1 of 4 arms: placebo, s.c. belimumab, i.v. rituximab, or sequential belimumab + rituximab.RESULTSOverall, 60 patients completed treatment and follow-up until week 68. The incidence of adverse events (AEs) and drug-related AEs was similar across groups. Infections/infestations were the most common AEs, and no serious infections of special interest occurred. Near-complete depletion of minor salivary gland CD20+ B cells and a greater and more sustained depletion of peripheral CD19+ B cells were observed with belimumab + rituximab versus monotherapies. With belimumab + rituximab, reconstitution of peripheral B cells occurred, but it was delayed compared with rituximab. At week 68, mean (± standard error) total EULAR Sjögren's syndrome disease activity index scores decreased from 11.0 (1.17) at baseline to 5.0 (1.27) for belimumab + rituximab and 10.4 (1.36) to 8.6 (1.57) for placebo.CONCLUSIONThe safety profile of belimumab + rituximab in pSS was consistent with the monotherapies. Belimumab + rituximab induced enhanced salivary gland B cell depletion relative to the monotherapies, potentially leading to improved clinical outcomes.TRIAL REGISTRATIONClinicalTrials.gov NCT02631538.FUNDINGFunding was provided by GSK.

Perturbing DDR signaling enhances cytotoxic effects of local oncolytic virotherapy and modulates the immune environment in glioma.

CAN-2409 is a replication-deficient adenovirus encoding herpes simplex virus (HSV) thymidine kinase (tk) currently in clinical trials for treatment of glioblastoma. The expression of tk in transduced cancer cells results in conversion of the pro-drug ganciclovir into a toxic metabolite causing DNA damage, inducing immunogenic cell death and immune activation. We hypothesize that CAN-2409 combined with DNA-damage-response inhibitors could amplify tumor cell death, resulting in an improved response. We investigated the effects of ATR inhibitor AZD6738 in combination with CAN-2409 in vitro using cytotoxicity, cytokine, and fluorescence-activated cell sorting (FACS) assays in glioma cell lines and in vivo with an orthotopic syngeneic murine glioma model. Tumor immune infiltrates were analyzed by cytometry by time of flight (CyTOF). In vitro, we observed a significant increase in the DNA-damage marker γH2AX and decreased expression of PD-L1, pro-tumorigenic cytokines (interleukin-1ß [IL-1ß], IL-4), and ligand NKG2D after combination treatment compared with monotherapy or control. In vivo, long-term survival was increased after combination treatment (66.7%) compared with CAN-2409 (50%) and control. In a tumor re-challenge, long-term immunity after combination treatment was not improved. Our results suggest that ATR inhibition could amplify CAN-2409's efficacy in glioblastoma through increased DNA damage while having complex immunological ramifications, warranting further studies to determine the ideal conditions for maximized therapeutic benefit.

A randomised, placebo-controlled study of RIPK1 inhibitor GSK2982772 in patients with active ulcerative colitis.

OBJECTIVE: Tumour necrosis factor signalling via the receptor-interacting protein kinase 1 (RIPK1) pathway regulates colonic inflammation suggesting that RIPK1 inhibition may be a potential therapeutic target in ulcerative colitis (UC). This phase IIa, randomised, double-blind experimental medicine study investigated the safety, pharmacokinetics (PK), pharmacodynamics (PD) and preliminary efficacy of the RIPK1 inhibitor GSK2982772 in patients with active UC. DESIGN: In part A, prior to a protocol amendment, one patient was randomised to receive GSK2982772 60 mg twice daily for 42 days. After the amendment, patients were randomised 2:1 to receive GSK2982772 60 mg or placebo three times daily for 42 days. In part B, all patients switched to open-label GSK2982772 60 mg three times daily for 42 days. Safety, PK, PD biomarkers, histological disease activity, clinical efficacy and quality of life were assessed at days 43 and 85. RESULTS: Thirty-six patients were randomised (n=12, placebo/open-label GSK2982772; n=24, GSK2982772/open-label GSK2982772). Most adverse events were mild, with headache reported the most frequently across groups (placebo/open-label GSK2982772, n=2 (17%); GSK2982772/open-label GSK2982772, n=8 (33%)). GSK2982772 was well distributed into colonic tissue, with generally higher concentrations in colonic biopsy samples versus plasma. No apparent differences between treatment groups were observed for PD, histological disease activity, clinical disease activity or quality-of-life measures. At screening, all patients had Mayo endoscopic scores of 2 or 3. At day 43, no patients in the placebo/open-label GSK2982772 group achieved Mayo endoscopic scores of 0 or 1 vs 3/24 (13%) for GSK2982772/open-label GSK2982772. At day 85, 1/9 (11%) achieved scores of 0 or one for placebo/open-label GSK2982772 vs 3/22 (14%) for GSK2982772/open-label GSK2982772. CONCLUSION: GSK2982772 was generally well tolerated, with no treatment-related safety concerns identified. However, no significant differences in efficacy were observed between treatment groups, suggesting that GSK2982772 as monotherapy is not a promising treatment for patients with active UC. TRIAL REGISTRATION NUMBER: NCT02903966.

A randomized, placebo-controlled experimental medicine study of RIPK1 inhibitor GSK2982772 in patients with moderate to severe rheumatoid arthritis.

BACKGROUND: Receptor-interacting protein kinase 1 (RIPK1) is a key mediator of inflammation through cell death and proinflammatory cytokine production. This multicenter, randomized, double-blind (sponsor-unblinded), placebo-controlled, experimental medicine study evaluated the safety, pharmacokinetics (PK), and preliminary efficacy of GSK2982772, a RIPK1 inhibitor, in moderate to severe rheumatoid arthritis (RA). METHODS: Patients with moderate to severe RA who had received ≥12 weeks' stable-dose conventional synthetic disease-modifying antirheumatic drug (csDMARD) therapy were randomized (2:1) to GSK2982772 60 mg or placebo orally 2 or 3 times daily for 84 days. Safety, PK, disease activity, joint damage, and pharmacodynamic (PD) biomarkers were assessed at days 43 and 85. RESULTS: A total of 52 patients were randomized (placebo, 18; GSK2982772, 34). Adverse events (AEs) were reported in 13 (72%) in patients in the placebo group (n = 3 b.i.d; n = 10 t.i.d.) and 20 (61%) in the GSK2982772 group (n = 3 b.i.d; n = 17 t.i.d.). All treatment-related AEs were mild/moderate, except one severe case of alopecia areata at day 49 and retinal vein thrombosis at day 66 (which led to withdrawal from the study) in patients receiving GSK2982772 t.i.d. Disease Activity Score in 28 Joints-C-reactive protein (DAS28-CRP) scores, ACR20/50/70 response, and rates of low disease activity and remission were similar between placebo and GSK2982772 arms. CONCLUSIONS: These results suggest that inhibition of RIPK1 activity at the GSK2982772 exposure levels evaluated do not translate into meaningful clinical improvement of RA. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02858492 . Registered 8 August 2016.

cDC1 are required for the initiation of collagen-induced arthritis.

Rheumatoid arthritis (RA) is chronic autoimmune disease which etiology remains unknown. Several cell types have been described to potentiate/aggravate the arthritic process however the initiating event in synovial inflammation is still elusive. Dendritic cells (DCs) are essential for the initiation of primary immune responses and thus we hypothesized that these cells might be crucial for RA induction. DCs are a heterogeneous population of cells comprising different subsets with distinct phenotype and function. Here we investigated which DC subset(s) is/are crucial for the initiation of the arthritic process. We have previously demonstrated that Flt3-/- mice, with reduced DCs, were protected from collagen induced arthritis (CIA). Here we have shown that GM-CSF derived DCs in Flt3L-/- mice are functional but not sufficient to induce arthritis. Batf3-/- mice lacking both CD103+ and CD8α+ cDC1 were resistant to collagen induced arthritis (CIA), demonstrating that this DC subset is crucial for arthritis development. CEP-701 (a Flt3L inhibitor) treatment prevented CIA induction, and reduced dramatically the numbers CD103+ cDC1s present in the lymph nodes and synovium. Hence this study identified cDC1 as the main subset orchestrating the initiation of cell-mediated immunity in arthritis.

Incidence and risk factors for adalimumab and infliximab anti-drug antibodies in rheumatoid arthritis: A European retrospective multicohort analysis.

OBJECTIVES: To evaluate the incidence of anti-drug antibody (ADA) occurrences and ADA-related risk factors under adalimumab and infliximab treatment in rheumatoid arthritis (RA) patients. METHODS: The study combined retrospective cohorts from the ABIRISK project totaling 366 RA patients treated with adalimumab (n = 240) or infliximab (n = 126), 92.4% of them anti-TNF naive (n = 328/355) and 96.6% of them co-treated with methotrexate (n = 341/353) with up to 18 months follow-up. ADA positivity was measured by enzyme-linked immunosorbent assay. The cumulative incidence of ADA was estimated, and potential bio-clinical factors were investigated using a Cox regression model on interval-censored data. RESULTS: ADAs were detected within 18 months in 19.2% (n = 46) of the adalimumab-treated patients and 29.4% (n = 37) of the infliximab-treated patients. The cumulative incidence of ADA increased over time. In the adalimumab and infliximab groups, respectively, the incidence was 15.4% (5.2-20.2) and 0% (0-5.9) at 3 months, 17.6% (11.4-26.4) and 0% (0-25.9) at 6 months, 17.7% (12.6-37.5) and 34.1% (11.4-46.3) at 12 months, 50.0% (25.9-87.5) and 37.5% (25.9-77.4) at 15 months and 50.0% (25.9-87.5) and 66.7% (37.7-100) at 18 months. Factors associated with a higher risk of ADA development were: longer disease duration (1-3 vs. < 1 year; adalimumab: HR 3.0, 95% CI 1.0-8.7; infliximab: HR 2.7, 95% CI 1.1-6.8), moderate disease activity (DAS28 3.2-5.1 vs. < 3.2; adalimumab: HR 6.6, 95% CI 1.3-33.7) and lifetime smoking (infliximab: HR 2.7, 95% CI 1.2-6.3). CONCLUSIONS: The current study focusing on patients co-treated with methotrexate for more than 95% of them found a late occurrence of ADAs not previously observed, whereby the risk continued to increase over 18 months. Disease duration, DAS28 and lifetime smoking are clinical predictors of ADA development.

Fibroblasts and Osteoblasts in Inflammation and Bone Damage.

This review discusses the important role fibroblasts play in the process of inflammation and the evidence that these cells may drive the persistence of inflammation. Fibroblasts are key components of the stroma normally involved in maintenance of extracellular matrix and tissue function; however, the term 'fibroblast' is used to describe a heterogeneous population of cells that vary in phenotype both between and within anatomical sites. Fibroblasts possess Toll-like receptors allowing them to respond to pathogen and damage-related signals by producing proinflammatory mediators such as IL-6, PGE2, and GM-CSF and can produce a range of chemokines such as CXCL12, CXCL13, and CXCL8 which attract B and T lymphocytes, monocytes, and neutrophils to sites of inflammation. Interactions between leukocytes and fibroblasts can facilitate increased survival of the leukocytes and modulate phenotypes leading to differential gene expression in the presence of mediators involved in inflammation. Fibroblasts also contribute to collateral tissue damage during inflammation through the production of members of the metalloproteinase family and cathepsins and also through induction of osteoclastogenesis leading to increased bone resorption rates. In persistent diseases, fibroblasts obtain an imprinted, aggressive phenotype leading to the production of higher basal levels of proinflammatory cytokines and the ability to damage tissue in the absence of continual stimuli. This aggressive phenotype offers an attractive new target for therapeutics that could help alleviate the burden of persistent inflammation.

Induction of sustained remission in early inflammatory arthritis with the combination of infliximab plus methotrexate: the DINORA trial.

BACKGROUND: In the present study, we explored the effects of immediate induction therapy with the anti-tumour necrosis factor (TNF)α antibody infliximab (IFX) plus methotrexate (MTX) compared with MTX alone and with placebo (PL) in patients with very early inflammatory arthritis. METHODS: In an investigator-initiated, double-blind, randomised, placebo-controlled, multi-centre trial (ISRCTN21272423, http://www.isrctn.com/ISRCTN21272423 ), patients with synovitis of 12 weeks duration in at least two joints underwent 1 year of treatment with IFX in combination with MTX, MTX monotherapy, or PL randomised in a 2:2:1 ratio. The primary endpoint was clinical remission after 1 year (sustained for at least two consecutive visits 8 weeks apart) with remission defined as no swollen joints, 0-2 tender joints, and an acute-phase reactant within the normal range. RESULTS: Ninety patients participated in the present study. At week 54 (primary endpoint), 32% of the patients in the IFX + MTX group achieved sustained remission compared with 14% on MTX alone and 0% on PL. This difference (p < 0.05 over all three groups) was statistically significant for IFX + MTX vs PL (p < 0.05), but not for IFX + MTX vs MTX (p = 0.10), nor for MTX vs PL (p = 0.31). Remission was maintained during the second year on no therapy in 75% of the IFX + MTX patients compared with 20% of the MTX-only patients. CONCLUSIONS: These results indicate that patients with early arthritis can benefit from induction therapy with anti-TNF plus MTX compared with MTX alone, suggesting that intensive treatment can alter the disease evolution. TRIAL REGISTRATION: The trial was registered at http://www.isrctn.com/ISRCTN21272423 on 4 October 2007 (date applied)/12 December 2007 (date assigned). The first patient was included on 24 October 2007.

MiR-146a G/C rs2910164 variation in South African Indian and Caucasian patients with psoriatic arthritis.

BACKGROUND: Psoriasis and psoriatic arthritis (PsA) are inflammatory associated autoimmune disorders. MicroRNA (miR)-146a plays a crucial role in regulating inflammation. A single nucleotide polymorphism in the miR-146a gene (rs2910164), aberrantly alters its gene expression and linked with the pathogenesis of several disorders, including psoriasis and PsA. In South Africa, psoriasis and PsA are extremely rare in the indigenous African population and most common in both the Indian and Caucasian population. The aim of this study was to investigate whether the miR-146a rs2910164 contributes towards psoriasis and PsA development in South African Indian and Caucasian patients. METHODS: South African Indian (n = 84) and Caucasian (n = 32) PsA patients (total n = 116) and healthy control subjects (Indian: n = 62 and Caucasian: n = 38; total n = 100) were recruited in the study. DNA was extracted from whole blood taken from all subjects, and genotyped for the miR-146a rs2910164 using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Data for laboratory parameters were obtained from pathology reports. The consulting rheumatologist collected all other clinical data. RESULTS: Unstratified data (Caucasians + Indians): A significant decrease in C-reactive protein (CRP) levels in PsA patients was observed (CRP monitored at inclusion vs. after 6 months of treatment) (18.95 ± 2.81 mg/L vs. 9.68 ± 1.32 mg/L, p = 0.0011). The miR-146a rs2910164 variant C-allele frequency in PsA patients was significantly higher vs. healthy controls (35.78% vs. 26% respectively, p = 0.0295, OR = 1.59 95% CI 1.05-2.40). Stratified data (Indians): The variant C-allele frequency in Indian PsA patients was significantly higher vs. healthy Indian controls (35.71% vs. 22.58%, p = 0.0200, OR = 1.91 95% CI 1.13-3.22). Stratified data (Caucasians): The variant C-allele frequency distribution between Caucasian PsA patients and healthy Caucasian controls was similar. CONCLUSION: The rs2910164 variant C-allele may play a role in the progression of PsA in the South African Indian population. The main limitation in this study was the small sample size in the case-control cohorts, with a low overall statistical power (post-hoc power analysis = 19%).

Rheumatoid arthritis and psoriatic arthritis synovial fluids stimulate prolactin production by macrophages.

Prolactin (PRL) is a neuroendocrine hormone that can promote inflammation. We examined the synovial tissue and fluid levels of PRL in patients with inflammatory arthritis, PRL expression in differentiated Mϕs from patients with arthritis and from healthy donors, and the effects of different stimuli on PRL production by Mϕs. PRL levels were measured in paired synovial fluid (SF) and peripheral blood of patients with rheumatoid arthritis (RA, n = 19), psoriatic arthritis (PsA, n = 11), and gout (n = 11). Synovial-tissue PRL mRNA expression was measured by quantitative PCR in patients with RA (n = 25), PsA (n = 11), and gout (n = 12) and in Mϕs differentiated in SF of patients with RA, PsA, other subtypes of spondyloarthritis (SpA), and gout. Synovial-tissue PRL mRNA expression correlated significantly with clinical disease parameters in patients with RA and PsA, including erythrocyte sedimentation rate (ESR, r = 0.424; P = 0.049) and disease activity score evaluated in 28 joints (DAS28, r = 0.729; P = 0.017). Synovial-tissue PRL expression was similar in RA, PsA, and gout. PRL mRNA expression was detected in monocyte-derived Mϕs from patients with RA and was significantly higher (P ≤ 0.01) in Mϕs differentiated in pooled SF from patients with RA and PsA compared with SpA or gout. PRL production by Mϕ differentiation in the SF from patients with RA was not further regulated by stimulation with CD40L, IgG, LPS, or TNF. PRL is produced locally in the synovium of patients with inflammatory arthritis. The production of PRL by Mϕs was increased by unknown components of RA and PsA SF, where it could contribute to disease progression.

Computational Model Reveals Limited Correlation between Germinal Center B-Cell Subclone Abundancy and Affinity: Implications for Repertoire Sequencing.

Immunoglobulin repertoire sequencing has successfully been applied to identify expanded antigen-activated B-cell clones that play a role in the pathogenesis of immune disorders. One challenge is the selection of the Ag-specific B cells from the measured repertoire for downstream analyses. A general feature of an immune response is the expansion of specific clones resulting in a set of subclones with common ancestry varying in abundance and in the number of acquired somatic mutations. The expanded subclones are expected to have BCR affinities for the Ag higher than the affinities of the naive B cells in the background population. For these reasons, several groups successfully proceeded or suggested selecting highly abundant subclones from the repertoire to obtain the Ag-specific B cells. Given the nature of affinity maturation one would expect that abundant subclones are of high affinity but since repertoire sequencing only provides information about abundancies, this can only be verified with additional experiments, which are very labor intensive. Moreover, this would also require knowledge of the Ag, which is often not available for clinical samples. Consequently, in general we do not know if the selected highly abundant subclone(s) are also the high(est) affinity subclones. Such knowledge would likely improve the selection of relevant subclones for further characterization and Ag screening. Therefore, to gain insight in the relation between subclone abundancy and affinity, we developed a computational model that simulates affinity maturation in a single GC while tracking individual subclones in terms of abundancy and affinity. We show that the model correctly captures the overall GC dynamics, and that the amount of expansion is qualitatively comparable to expansion observed from B cells isolated from human lymph nodes. Analysis of the fraction of high- and low-affinity subclones among the unexpanded and expanded subclones reveals a limited correlation between abundancy and affinity and shows that the low abundant subclones are of highest affinity. Thus, our model suggests that selecting highly abundant subclones from repertoire sequencing experiments would not always lead to the high(est) affinity B cells. Consequently, additional or alternative selection approaches need to be applied.

Hormone, metabolic peptide, and nutrient levels in the earliest phases of rheumatoid arthritis-contribution of free fatty acids to an increased cardiovascular risk during very early disease.

Rheumatoid arthritis (RA) is a chronic autoimmune disease associated with changes in several hormones and metabolic peptides. Crosstalk between these factors and the immune system may be important for homeostasis during inflammation. Here, we studied the levels of hormones, metabolic peptides, and nutrients in individuals at risk for developing RA (at risk). In total, 18 hormones, metabolic peptides, and nutrients were measured in fasting serum samples from 45 autoantibody-positive individuals at risk, 22 RA patients, and 16 healthy subjects. Triglyceride (TG) levels were also measured in an independent validation cohort of 32 individuals at risk, 20 early arthritis patients, and 20 healthy controls. We found an elevated TG level in individuals at risk and significantly higher TG levels in RA patients compared to healthy controls. These results were confirmed in the validation cohort. Similarly, free fatty acid (FFA) levels showed an increase in individuals at risk and were significantly higher in RA patients compared to healthy controls. In RA patients, FFA levels were positively correlated with disease activity. Pancreatic polypeptide (PP) and norepinephrine levels were highly significantly increased in individuals at risk and RA patients compared to healthy controls. TG and FFA levels are increased in RA patients and positively correlated with disease activity parameters. The results presented here suggest a role for FFAs in the pathogenesis of RA. Furthermore, PP and norepinephrine may be a biomarker that could assist in the identification of individuals at risk.

B-cell imaging with zirconium-89 labelled rituximab PET-CT at baseline is associated with therapeutic response 24 weeks after initiation of rituximab treatment in rheumatoid arthritis patients.

BACKGROUND: B cells are key players in the pathogenesis of rheumatoid arthritis (RA). Although successful in 50-60% of patients with RA, anti-B-cell therapy given as rituximab could be more efficient by identifying potential responders prior to treatment. Positron emission tomography (PET) using radiolabeled rituximab for B-cell imaging might provide the means to fulfil this unmet clinical need. The objective of this study was to investigate the association between biodistribution of zirconium-89 (89Zr)-rituximab on PET-computed tomography (CT) and clinical response in patients with RA. METHODS: We included 20 patients with RA who were starting rituximab treatment. At the first intravenous (i.v.) therapeutic dose, patients were also injected with 89Zr-rituximab, followed by PET-CT. European League Against Rheumatism (EULAR) response criteria were applied to determine response at week 24. PET-CT was analyzed visually and quantitatively. Lymph node (LN) biopsies were performed at 0 and 4 weeks to correlate B-cell counts with imaging data. RESULTS: PET-positive hand joints (range 1-20) were observed in 18/20 patients. Responders had significantly higher 89Zr-rituximab uptake in PET-positive hand joints than non-responders (median target-to-background (T/B)) ratios (IQR) were 6.2 (4.0-8.8) vs. 3.1 (2.2-3.9), p = 0.02). At T/B ≥4.0, positive and negative predictive values for clinical response were respectively 90% and 75%. Quantitative 89Zr-rituximab hand joint uptake on PET correlated inversely with CD22+ B-cell count in LN tissue at 4 weeks of treatment (r = 0.6, p = 0.05). In addition, the CD22+ B-cell count in LN correlated positively with quantitative LN PET data at baseline, supporting the specificity of B-cell imaging on PET. CONCLUSIONS: Non-invasive B-cell imaging by 89Zr-rituximab PET-CT has promising clinical value to select RA responders to rituximab at baseline. 89Zr-rituximab PET-CT may also hold promise for monitoring anti-B-cell therapies in other B-cell driven autoimmune diseases, such as systemic lupus erythematosus and Sjögren's disease.

BET bromodomain inhibition reduces maturation and enhances tolerogenic properties of human and mouse dendritic cells.

Transcription of inflammatory genes is tightly regulated by acetylation and deacetylation of histone tails. An inhibitor of the acetylated-lysine reader bromodomain and extra-terminal domain (BET) proteins, I-BET151, is known to counteract the induction of expression of inflammatory genes in macrophages. We have investigated the effects of I-BET151 on dendritic cell function, including expression of co-stimulatory molecules and cytokines, and capacity for T cell activation. Treatment of mouse bone marrow derived dendritic cells (BMDC) and human monocyte derived DCs (mdDC) with I-BET151 reduced LPS-induced expression of co-stimulatory molecules, as well as the production of multiple cyokines and chemokines. Most strikingly, secretion of IL-6, IL-12 and IL-10 was significantly reduced to 89.7%, 99.9% and 98.6% respectively of that produced by control cells. I-BET151-treated mdDC showed a reduced ability to stimulate proliferation of autologous Revaxis-specific T cells. Moreover, while I-BET151 treatment of BMDC did not affect their ability to polarise ovalbumin specific CD4+ CD62L+ naive T cells towards Th1, Th2, or Th17 phenotypes, an increase in Foxp3 expressing Tregs secreting higher IL-10 levels was observed. Suppression assays demonstrated that Tregs generated in response to I-BET151-treated BMDC displayed anti-proliferative capacity. Finally, evidence that I-BET151 treatment can ameliorate inflammation in vivo in a T cell dependent colitis model is shown. Overall, these results demonstrate marked effects of BET inhibition on DC maturation, reducing their capacity for pro-inflammatory cytokine secretion and T cell activation and enhancing the potential of DC to induce Foxp3 expressing Treg with suppressive properties.

The prolactin receptor is expressed in rheumatoid arthritis and psoriatic arthritis synovial tissue and contributes to macrophage activation.

OBJECTIVES: Prolactin (PRL) is a lactation-inducing hormone with immunomodulatory properties and is found at elevated levels in the serum of patients with RA and other rheumatic diseases. The PRL receptor (PRLR) has been shown to be expressed by macrophages in atherosclerotic plaques. The aim of this study was to examine PRLR expression by synovial macrophages and its role in the regulation of macrophage activation. METHODS: Serum monomeric 23 kDa PRL levels were measured in 119 RA patients using a fluoroimmunometric assay. PRLR expression was assessed in synovial tissue of 91 RA, 15 PsA and 8 OA patients by immunohistochemistry and digital image analysis. Double IF was used to identify PRLR-expressing cells. The effects of PRL on monocyte-derived macrophage gene expression were examined by quantitative real-time PCR and ELISA. RESULTS: Serum PRL levels were similar in female and male RA patients. Median (interquartile range) PRLR expression was significantly higher (P < 0.05) in RA and PsA synovial tissue compared with OA. PRLR colocalized with synovial CD68+ macrophages and von Willebrand factor+ endothelial cells. In vitro, PRLR was prominently expressed in IFN-γ-and IL-10-polarized macrophages compared with other polarizing conditions. PRL by itself had negligible effects on macrophage gene expression, but cooperated with CD40L and TNF to increase expression of pro-inflammatory genes including IL-6, IL-8 and IL-12ß. CONCLUSIONS: Synovial PRLR expression is enhanced in patients with inflammatory arthritis compared with OA, and PRL cooperates with other pro-inflammatory stimuli to activate macrophages. These results identify PRL and PRLR as potential new therapeutic targets in inflammatory arthritis.

Psoriatic arthritis: An assessment of clinical, biochemical and radiological features in a single-centre South African cohort.

BACKGROUND: Although psoriatic arthritis (PsA) is a well-documented clinical entity, epidemiological, clinical and radiological studies of South African (SA) patients are scarce. OBJECTIVES: To assess clinical, biochemical and radiological features in a single-centre SA cohort. METHODS: We conducted a prospective assessment of the clinical, biochemical and radiological features of 384 consecutive patients with PsA seen at the rheumatology clinic at Prince Mshiyeni Memorial Hospital, Durban, SA, between January 2007 and December 2013. Patients were assessed at enrolment and 6 months after enrolment. They were classified into five groups as described by Moll and Wright, being entered into the group that best described the clinical manifestations. Clinicopathological characteristics recorded at enrolment were age at the time of examination, racial background, personal and family medical history, age and symptoms at the onset of PsA, pattern of joint involvement, joint pain, and the relationship between joint pain and the onset of PsA. RESULTS: Of the patients, 59.1% had a polyarticular presentation indistinguishable from rheumatoid arthritis, 19.0% had distal interphalangeal involvement, 9.1% had spondyloarthropathy, 11.9% had oligoarthritis and 0.9% had arthritis mutilans. The epidemiological trends (male/female ratio 1.45:1, mean age at onset of arthritis 50.2 (standard deviation 11.8) years, female preponderance in the polyarticular group and male preponderance in the spondyloarthropathy and oligoarticular groups) were similar to trends published elsewhere. A notable characteristic of our cohort was the complete absence of black South Africans with PsA. CONCLUSIONS: The complete absence of black South Africans with PsA is interesting. We anticipate that our findings will prompt genetic studies to isolate both protective and susceptibility genes for further elucidating PsA.

Neo-Epitopes--Fragments of Cartilage and Connective Tissue Degradation in Early Rheumatoid Arthritis and Unclassified Arthritis.

OBJECTIVE: Tissue destruction in rheumatoid arthritis (RA) is predominantly mediated by matrix metalloproteinases (MMPs), thereby generating protein fragments. Previous studies have revealed that these fragments include MMP-mediated collagen type I, II, and III degradation, citrullinated and MMP-degraded vimentin and MMP degraded C-reactive protein. We evaluated if biomarkers measuring serum levels of specific sequences of the mentioned fragments would provide further information of diagnostic and/or prognostic processes in early arthritis. METHODS: Ninety-two early arthritis patients (arthritis duration<1 year, DMARD naïve) were enrolled. Patients either fulfilled the ACR/EULAR2010 criteria for RA (n = 60) or had unclassified arthritis (UA) (n = 32). Patients fulfilling the RA criteria after 2 years follow-up were classified into non-erosive (n = 25), or erosive disease (n = 13). Concentrations of the biomarkers: C1M, C2M, C3M, VICM and CRPM were measured in baseline serum. RESULTS: C1M, C3M and CRPM were able to discriminate between the UA and RA baseline diagnosis in 92 patients with an AUROC of 0.64 (95%CI 0.517 to 0.762), 0.73 (95%CI 0.622 to 0.838) and 0.68 (95%CI 0.570 to 0.795). C2M showed a potential for discrimination between non-erosive and erosive disease in 38 patients with an AUROC of 0.75 (95%CI 0.597 to 0.910). All of the applied biomarkers correlated with one or more of the disease activity parameters: DAS28, ESR, CRP, SJC66, TJC68 and/or HAQ. CONCLUSION: This is the first study evaluating the applied biomarkers at this early stage of arthritis. C1M, C3M, CRPM might be the best diagnostic marker, whereas high levels of C2M indicated progression of disease at follow-up in early RA patients.

Evaluation of Minimally Invasive, Ultrasound-guided Synovial Biopsy Techniques by the OMERACT Filter--Determining Validation Requirements.

OBJECTIVE: Because limited data currently support the clinical utility of peripherally expressed biomarkers in guiding treatment decisions for patients with rheumatoid arthritis, the search has turned to the disease tissue. The strategic aim of the Outcome Measures in Rheumatology (OMERACT) synovitis working group over the years has been to develop novel diagnostic and prognostic synovial biomarkers. A critical step in this process is to refine and validate minimally invasive, technically simple, robust techniques to sample synovial tissue, for use both in clinical trials and routine clinical practice. The objective of the synovitis working group (SWG) at OMERACT 12 (2014) was to examine whether recently developed ultrasound (US)-guided synovial biopsy techniques could be validated according to the OMERACT filter for future clinical use recommendation. METHODS: The SWG examined whether current data reporting US-guided synovial biopsy of both large and small joints addressed the OMERACT filters of truth, discrimination, and feasibility. RESULTS: There are currently limited data examining the performance of US-guided synovial biopsy, mainly from observational studies. Thus, it remains critical to evaluate its performance, within the clinical trials context, against the current gold standard of arthroscopic biopsy, with particular reference to: (1) synovial tissue yield, (2) capacity to determine treatment response as measured by a validated synovial biomarker, and (3) tolerability of the procedure. CONCLUSION: We summarize the discrete work packages agreed to as requirements to validate US-guided synovial biopsy and therefore lead to a global consensus on the use of synovial biopsy for research and clinical practice.

Anti-interleukin 6 receptor therapy for hyper-IgD syndrome.

Hyper-IgD syndrome (HIDS) is a rare, severe hereditary autoinflammatory disease characterised by periodic fevers, elevated serum IgD levels and a wide range of symptoms. Although a few randomised controlled trials have been performed in this disorder, there are no straightforward treatment protocols and none of the potential therapies are registered for this indication. We report a case of a young woman with severe HIDS who failed numerous therapies. Eventually, rational treatment with a monoclonal anti-interleukin 6 receptor antibody was initiated. This therapy resulted in an impressive clinical improvement and reduction in the number of hospital admissions per year. This case report underlines the difficulty of finding a suitable treatment for rare, severe inflammatory diseases. Furthermore, we show that treating patients with targeted therapies may result in clinical benefit for the patient, as well as simultaneously teach us more about the pathophysiology of these rare, relatively understudied diseases.

Expression of Prostaglandin E2 Enzymes in the Synovium of Arthralgia Patients at Risk of Developing Rheumatoid Arthritis and in Early Arthritis Patients.

OBJECTIVE: Arthralgia may precede the development of synovial inflammation in autoantibody-positive individuals at risk of developing rheumatoid arthritis (RA). A major pathway involved in pain is the prostaglandin (PG) E2 pathway. We investigated this pathway in the synovium of individuals with RA-specific autoantibodies and in early arthritis patients. METHODS: Nineteen autoantibody-positive individuals (IgM-rheumatoid factor and/or anti-cyclic citrullinated peptide antibodies) with arthralgia (n=15) and/or a positive family history of RA (n=8), who had been prospectively followed for at least 2 years, were included. In addition, we included early arthritis patients (disease-modifying antirheumatic drug naïve) who after 2 years follow up fulfilled classification criteria for RA (n=63), spondyloarthritis (SpA; n=14), or had unclassified arthritis (UA; n=27). In all subjects we assessed pain and performed synovial biopsy sampling by mini-arthroscopy at baseline. Tissue sections were examined by immunohistochemistry to detect and quantify PGE2 pathway enzymes expression levels (mPGES-1; COX-1 and -2; 15-PGDH). RESULTS: In both study groups synovial expression of PGE2 enzymes was not clearly related to pain sensation. Expression levels at baseline were not associated with the development of arthritis after follow up (6 out of 19 autoantibody-positive individuals). However, in early SpA patients the expression levels of mPGES-1 and COX-1 were significantly increased compared to RA and UA patients. CONCLUSION: Pain in autoantibody-positive individuals without synovial inflammation who are at risk of developing RA and in early arthritis patients may be regulated by pathways other than the PGE2 pathway or originate at sites other than the synovium. In contrast, in SpA, the PGE2 pathway may be inherently linked to the pathophysiology/etiology of the disease.