Secukinumab efficacy on resolution of enthesitis in psoriatic arthritis: pooled analysis of two phase 3 studies.

Background: Enthesitis is one of the psoriatic arthritis (PsA) domains. Patients with enthesitis are associated with worse outcomes than those without enthesitis. The effect of secukinumab on the resolution of enthesitis in patients with PsA was explored using pooled data from the FUTURE 2 and 3 studies.

The role of microRNA-155/liver X receptor pathway in experimental and idiopathic pulmonary fibrosis.

Background: Idiopathic pulmonary fibrosis (IPF) is progressive and rapidly fatal. Improved understanding of pathogenesis is required to prosper novel therapeutics. Epigenetic changes contribute to IPF; therefore, microRNAs may reveal novel pathogenic pathways.

ACKR4 on Stromal Cells Scavenges CCL19 To Enable CCR7-Dependent Trafficking of APCs from Inflamed Skin to Lymph Nodes.

Dermal dendritic cells and epidermal Langerhans cells are APCs that migrate from skin to draining lymph nodes (LN) to drive peripheral tolerance and adaptive immunity. Their migration requires the chemokine receptor CCR7, which directs egress from the skin via dermal lymphatic vessels and extravasation into the LN parenchyma from lymph in the subcapsular sinus. CCR7 is activated by two chemokines: CCL19 and CCL21.

Targeting cell migration in rheumatoid arthritis.

Purpose Of Review: To provide an update of past failures, future prospects and key challenges facing the therapeutic targeting of chemokines and their receptors in rheumatoid arthritis.

Recent Findings: Clinical trials in rheumatoid arthritis have been undertaken with small molecule antagonists or neutralizing antibodies targeting CCR1, CCR5 and CXCL10. Some encouraging results have emerged.

The liver X receptor pathway is highly upregulated in rheumatoid arthritis synovial macrophages and potentiates TLR-driven cytokine release.

Objectives: Macrophages are central to the inflammatory processes driving rheumatoid arthritis (RA) synovitis. The molecular pathways that are induced in synovial macrophages and thereby promote RA disease pathology remain poorly understood.

Methods: We used microarray to characterise the transcriptome of synovial fluid (SF) macrophages compared with matched peripheral blood monocytes from patients with RA (n=8).

CCX-CKR deficiency alters thymic stroma impairing thymocyte development and promoting autoimmunity.

The atypical chemokine receptor CCX-CKR regulates bioavailability of CCL19, CCL21, and CCL25, homeostatic chemokines that play crucial roles in thymic lymphopoiesis. Deletion of CCX-CKR results in accelerated experimental autoimmunity induced by immunization. Here we show that CCX-CKR deletion also increases incidence of a spontaneous Sjögren's syndrome-like pathology, characterized by lymphocytic infiltrates in salivary glands and liver of CCX-CKR(-/-) mice, suggestive of a defect in self-tolerance when CCX-CKR is deleted.

Soluble ST2 associates with diabetes but not established cardiovascular risk factors: a new inflammatory pathway of relevance to diabetes?

Preliminary data mostly from animal models suggest the sST2/IL-33 pathway may have causal relevance for vascular disease and diabetes and thus point to a potential novel inflammatory link to cardiometabolic disease. However, the characterisation of sST2 levels in terms of metabolic or vascular risk in man is completely lacking. We sought to address this gap via a comprehensive analysis of risk factor and vascular correlates of sST2 in a cross-sectional study (pSoBid).

Simultaneous activation of the liver X receptors (LXRα and LXRβ) drives murine collagen-induced arthritis disease pathology.

Background: It has previously been shown that dual activation of the Liver X Receptors (LXRα and LXRβ) by the agonist, GW3965, enhances pathology in a murine model of collagen-induced arthritis.

Objective: To determine whether LXRα or LXRβ have discrete roles in driving articular inflammation.

Methods: Arthritis was induced in male C57BL/6 wild-type (WT), LXRα-/-, LXRβ-/- and LXRα/β double KO mice by injection with type II collagen and treated with 30 mg/kg of the LXR agonist GW3965 or vehicle control.

MicroRNA-155 as a proinflammatory regulator in clinical and experimental arthritis.

MicroRNA (miRNA) species (miR) regulate mRNA translation and are implicated as mediators of disease pathology via coordinated regulation of molecular effector pathways. Unraveling miR disease-related activities will facilitate future therapeutic interventions. miR-155 recently has been identified with critical immune regulatory functions.

IL-33 induces skin inflammation with mast cell and neutrophil activation.

Psoriasis is a common chronic autoimmune condition of the skin characterized by hyperplasia of epidermal keratinocytes associated with pro-inflammatory cytokines. IL-33 is a new member of the IL-1 superfamily that signals through the ST2 receptor and was originally defined as an inducer of T helper 2 (Th2) cytokines. Recently, broader immune activatory potential has been defined for IL-33 particularly via mast cell activation and neutrophil migration.

Quantitative detection of human tumor necrosis factor α by a resonance raman enzyme-linked immunosorbent assay.

Tumor necrosis factor α is an inflammatory cytokine which has been linked with many infectious and inflammatory diseases. Detection and quantification of this key biomarker is commonly achieved by use of an enzyme-linked immunosorbent assay (ELISA). This fundamental technique uses the spectroscopic detection of a chromogen such as 3,3',5,5'-tetramethylbenzidine (TMB).

Embracing novel cytokines in RA - complexity grows as does opportunity!

Current therapeutics for the treatment of rheumatoid arthritis (RA) offer limited efficacy in a restricted number of patients. There is, therefore, an unmet clinical need for the development of more efficacious therapeutics for the treatment of disease. Anti-TNFalpha therapy has provided proof of principle that cytokine blockade is an appropriate strategy by which to inhibit disease progression.

Interleukin-33 induces protective effects in adipose tissue inflammation during obesity in mice.

Rationale: Chronic low-grade inflammation involving adipose tissue likely contributes to the metabolic consequences of obesity. The cytokine interleukin (IL)-33 and its receptor ST2 are expressed in adipose tissue, but their role in adipose tissue inflammation during obesity is unclear.

Objective: To examine the functional role of IL-33 in adipose tissues and investigate the effects on adipose tissue inflammation and obesity in vivo.

Mast cells express IL-17A in rheumatoid arthritis synovium.

The proinflammatory cytokine IL-17A is considered a crucial player in rheumatoid arthritis (RA) pathogenesis. In experimental models of autoimmune arthritis, it has been suggested that the cellular source of IL-17A is CD4(+) T cells (Th17 cells). However, little is known about the source of IL-17 in human inflamed RA tissue.

Apolipoprotein E-deficient mice are resistant to the development of collagen-induced arthritis.

Objective: To determine whether elevated serum lipid levels resulting from feeding animals a high-fat diet can affect the inflammatory process in C57BL/6 (B6) wild-type (WT) and B6 ApoE(-/-) mouse models of collagen-induced arthritis (CIA).

Methods: Male B6 WT or ApoE(-/-) mice were fed either a normal chow diet or a high-fat diet. CIA was induced in mice at 12 weeks of age using type II chicken collagen, Freund's complete adjuvant, and, on occasion, a lipopolysaccharide boost.

Liver X receptor agonism promotes articular inflammation in murine collagen-induced arthritis.

Objective: Liver X receptors (LXRs) have previously been implicated in the regulation of inflammation and have, in general, been ascribed an antiinflammatory role. This study was therefore undertaken to explore the biologic mechanisms of LXRs in vivo and in vitro in an experimental inflammatory arthritis model.

Methods: Male DBA/1 mice were immunized with type II collagen and treated from an early or established stage of arthritis with 2 different concentrations of the LXR agonists T1317 and GW3965 or vehicle control.

Animal models of rheumatoid arthritis.

Animal models have been used extensively in studies of rheumatoid arthritis pathogenesis. Despite the inherent limitations of all animal models, several rodent models have significantly progressed our understanding of the fundamental mechanisms underpinning rheumatoid arthritis and contributed to several current major advances in treatment. These models include the induced arthritis models such as collagen-induced arthritis, collagen-antibody-induced arthritis, zymosan-induced arthritis, and the methylated BSA model, and the genetically manipulated or spontaneous arthritis models such as the TNF-alpha-transgenic mouse, K/BxN mouse, and the Skg mouse.

IL-33 reduces the development of atherosclerosis.

Atherosclerosis is a chronic inflammatory disease of the vasculature commonly leading to myocardial infarction and stroke. We show that IL-33, which is a novel IL-1-like cytokine that signals via ST2, can reduce atherosclerosis development in ApoE(-/-) mice on a high-fat diet. IL-33 and ST2 are present in the normal and atherosclerotic vasculature of mice and humans.

Emerging cytokine targets in rheumatoid arthritis.

Purpose Of Review: The utility of cytokines as therapeutic targets in rheumatoid arthritis has been unequivocally demonstrated by the success of tumour necrosis factor blockade in clinical practice. Partial and non-responses to tumour necrosis factor blocking agents, however, together with the increasing clinical drive to remission induction, requires that further therapeutic targets be identified.

Recent Findings: Numerous cytokine activities with pathogenetic potential have now been demonstrated in rheumatoid arthritis synovial membrane, including members of the IL-1 superfamily and the IL-12 superfamily.