Effect of inhibition of interleukin-12/23 by ustekinumab on the expression of leptin and leptin receptor in human THP-1 macrophages.

BACKGROUND: Leptin, an adipocyte-derived circulating cytokine that signals nutritional status, may play a role in the development of psoriasis and its associated systemic diseases. Patients with psoriasis have significantly decreased serum leptin levels compared with controls. AIM: To investigate the effect of two commonly used anti-psoriatic biologic drugs, adalimumab and ustekinumab, on leptin and leptin receptor expression in human macrophages. METHODS: THP-1 differentiated macrophages were cultured under the following conditions: (i) untreated control, (ii) adalimumab 5 µg/mL, (iii) ustekinumab 1 µg/mL and (iv) ustekinumab 5 µg/mL. Expression of leptin and leptin receptors were measured using real-time quantitative PCR and immunoblotting techniques. RESULTS: The presence of either adalimumab or ustekinumab in growth medium significantly upregulated expression of leptin receptor in THP-1 human macrophages to 1.98 ± 0.47 and 2.09 ± 0.24, respectively (n = 3, P < 0.01) vs. 1.12 ± 0.19 for untreated control cells. However, only ustekinumab at a concentration of 5 µg/mL augmented expression of leptin to 1.99 ± 0.56 (n = 3, P < 0.01) vs. control untreated cells. CONCLUSIONS: Enhanced leptin and leptin receptor expression in macrophages exposed to therapeutic levels of ustekinumab suggest a novel immunomodulatory mechanism for this biologic drug. Further mechanistic studies may yield targeted treatment using the leptin pathway, which could reduce the common obesity-related complications of psoriasis while alleviating symptoms and improving prognosis.

2015 Recommendations for the management of polymyalgia rheumatica: a European League Against Rheumatism/American College of Rheumatology collaborative initiative

Therapy for polymyalgia rheumatica (PMR) varies widely in clinical practice as international recommendations for PMR treatment are not currently available. In this paper, we report the 2015 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) recommendations for the management of PMR. We used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology as a framework for the project. Accordingly, the direction and strength of the recommendations are based on the quality of evidence, the balance between desirable and undesirable effects, patients' and clinicians' values and preferences, and resource use. Eight overarching principles and nine specific recommendations were developed covering several aspects of PMR, including basic and follow-up investigations of patients under treatment, risk factor assessment, medical access for patients and specialist referral, treatment strategies such as initial glucocorticoid (GC) doses and subsequent tapering regimens, use of intramuscular GCs and disease modifying anti-rheumatic drugs (DMARDs), as well as the roles of non-steroidal anti-rheumatic drugs and non-pharmacological interventions. These recommendations will inform primary, secondary and tertiary care physicians about an international consensus on the management of PMR. These recommendations should serve to inform clinicians about best practices in the care of patients with PMR.(AU)

Plasma IL-33 in atopic patients correlates with pro-inflammatory cytokines and changes cholesterol transport protein expression: a surprising neutral overall impact on atherogenicity.

OBJECTIVE: Interleukin (IL)-33 has been associated with atopic and inflammatory conditions. IL-33 may be atheroprotective inducing a Th1-to-Th2 immunologic switch. However, the role of IL-33 in cardiovascular disease remains unclear. This study examines the effect of physiological and elevated IL-33 levels in plasma from atopic patients (AP) on cholesterol metabolism in human macrophages as compared to plasma from healthy controls (HC). METHODS: Twenty-five AP and 25 HC were enrolled in this study. Plasma samples were analysed for levels of IL-33, IFN-γ, TNF-α, IL-17α, IL-5 and soluble ST2. THP-1 differentiated macrophages were exposed to HC and AP plasma. Expression of proteins involved in reverse cholesterol transport (ABCA1, ABCG1 and 27-hydroxylase) and scavenger receptors, responsible for uptake of modified lipids (CD36, ScR-A1, CXCL16 and LOX-1), was measured using QRT-PCR and immunoblotting techniques. RESULTS: IL-33 was significantly higher in AP plasma: 106.7 ± 95 pg/mL versus HC plasma (53.4 ± 23 pg/mL). IL-33 concentration strongly correlated with levels of IFN-γ (r = 0.85), TNFα (r = 0.9) and IL-17α (r = 0.94). No significant difference was found in soluble ST2 levels. An important contrast was observed for 27-hydroxylase: normal IL-33 in AP plasma amplified 27-hydroxylase while increased IL-33 suppressed it. Expression of CD36 and SR-A1 was greater in macrophages exposed to plasma with high IL-33, while CXCL16 was higher in cells grown in the presence of plasma with normal IL-33. CONCLUSIONS: Here, we demonstrate that high levels of IL-33 and a high IL-33/soluble ST2 ratio correlates with elevated levels of IFN-γ, TNF-α and IL-17α as well as IL-5, demonstrating that IL-33 has pleiotropic effects. However, elevated IL-33 did not significantly impact lipid accumulation in macrophages overall. Given the wide variety of cellular responses regulated by IL-33, further investigation with a larger sample size will allow us to clarify the threshold concentration of IL-33 that leads to optimal cholesterol balance.

Classification criteria for Sjögren's syndrome: a revised version of the European criteria proposed by the American-European Consensus Group.

Classification criteria for Sjögren's syndrome (SS) were developed and validated between 1989 and 1996 by the European Study Group on Classification Criteria for SS, and broadly accepted. These have been re-examined by consensus group members, who have introduced some modifications, more clearly defined the rules for classifying patients with primary or secondary SS, and provided more precise exclusion criteria.

Preferential recognition of a fragment species of osteoarthritic synovial fluid fibronectin by antibodies to the alternatively spliced EIIIA segment.

OBJECTIVE: To characterize the species of synovial fluid (SF) fibronectin (FN) bearing the alternatively spliced EIIIA segment. METHODS: SF from patients with osteoarthritis (OA) and rheumatoid arthritis (RA), as well as corresponding affinity isolation products, were subjected to 1-dimensional and 2-dimensional electrophoresis followed by Western blot analysis. RESULTS: Regardless of the clinical type of arthritis, a polyclonal antibody that recognizes antigenic determinants throughout the FN molecule produced staining of predominantly approximately 200+ and approximately 170-kd species in reduced 1-dimensional electrophoresis. Despite the overall prevalence of the larger species, 4 monoclonal antibodies (mAb) reactive with sequences lying near the center of the EIIIA segment exhibited a relative failure to recognize the larger of these 2 species in OA, but not RA, SF. The absence of recognition of EIIIA sequences within the approximately 200+ kd forms of OA SF FN was unrelated to their derivation from dimers, since anti-EIIIA mAb recognized the smaller fragment species in preference to both monomeric and dimeric forms. The approximately 170-kd EIIIA+ fragments were observed to have minimal gelatin-binding capacity and appeared on 2-dimensional electrophoresis to extend from the N-terminus of FN through at least the center of the EIIIA segment. Similar results were obtained for samples obtained by needle aspiration or arthroscopic lavage, suggesting a widespread applicability of these findings. CONCLUSION: The approximately 170-kd EIIIA+ species of FN could potentially constitute a soluble "vehicle" by which chondrocyte-regulating EIIIA sequences, liberated from inhibitory flanking C-terminal sequences, could reach cells in the arthritic joint. Additionally, "FN species-specific" recognition of this segment within OA SF could constitute a marker by which to gauge the activity of the OA disease process.

A review and update of Sjögren's syndrome: manifestations, diagnosis, and treatment.

Sjögren's syndrome is an autoimmune disorder that affects approximately 1% of the population. It is a disease that in recent years has not been studied extensively, but for which much study is needed. Diagnosis of this disease is extremely difficult. Until recently no strong consensus on diagnostic criteria has been published. The disease can cause dry eyes, dry mouth, vasculitis, and neurologic disease, and each symptom may be at times correctly attributed to Sjögren's or incorrectly attributed to another disease. Because it affects many different areas, many specialists (rheumatologists, primary care physicians, ophthalmologists, and dentists) have to be educated about Sjögren's syndrome's pathogenesis, manifestations, diagnosis, and treatments to manage this disease and help improve these patients' quality of life.

Dendritic cells (DCs) in rheumatoid arthritis (RA): progenitor cells and soluble factors contained in RA synovial fluid yield a subset of myeloid DCs that preferentially activate Th1 inflammatory-type responses.

There is evidence that mature dendritic cells (DCs) present in the rheumatoid arthritis (RA) joint mediate immunopathology in RA. In this study, we indicate that early myeloid progenitors for DCs and DC growth factors existing in RA synovial fluid (SF) are also likely participants in the RA disease process. A fraction of cells lacking markers associated with mature DCs or DC precursors and enriched in CD34(negative) myeloid progenitors was isolated from RA SF. These cells proliferated extensively when cultured in vitro with cytokines that promote the growth of myeloid DCs (GM-CSF/TNF/stem cell factor/IL-4) and, to a lesser degree, when cultured with monocyte/granulocyte-restricted growth factors (M-CSF/GM-CSF). Mature DCs derived from RA SF progenitors with CD14-DC cytokines known to be prevalent in the inflamed RA joint (GM-CSF/TNF/stem cell factor/IL-13) were potent stimulators of allogeneic T cells and inflammatory-type Th1 responses and included CD14-DC subtypes. Cell-free RA SF facilitated DC maturation from myeloid progenitors, providing direct evidence that the inflamed RA joint environment instructs DC growth. Enhanced development of CD14-derived DCs was correlated with the presence of soluble TNFR (p55), raising the possibility that soluble TNFR also regulate CD14-derived DC growth in vivo. SF from patients with osteoarthritis contained neither myeloid DC progenitors nor DC growth factors. The existence of DC progenitors and myeloid DC growth factors in RA SF supports the concept that RA SF may be a reservoir for joint-associated DCs and reveals a compelling mechanism for the amplification and perpetuation of DC-driven responses in the RA joint, including inflammatory-type Th1 responses.

Detection and quantitation of stem cell factor (kit ligand) in the synovial fluid of patients with rheumatic disease.

OBJECTIVE: To identify and quantitate stem cell factor (SCF; kit ligand) in the serum and synovial fluid (SF) of patients with rheumatoid arthritis (RA) and to compare these values with those measured in normal serum, RA serum, SF of patients with other rheumatic diseases, and conditioned medium from cultured synoviocytes. METHODS: SCF was measured in serum, SF, and conditioned synovial cell culture medium by a sensitive ELISA. Results were correlated with hematologic variables including white blood cell count, hemoglobin, platelet count, erythrocyte sedimentation rate, and rheumatoid factor. RESULTS: SCF levels in RA SF exceeded those measured in RA serum, osteoarthritis SF, and SF from patients with other inflammatory arthropathies. SCF was detectable in conditioned medium from cultured synoviocytes. CONCLUSION: High levels of SCF are present in RA serum and SF. Local production of SF may influence expansion of myeloid progenitor cells and mast cell function in RA.

Fibronectin fragments and their role in inflammatory arthritis.

OBJECTIVES: To identify potential immunopathogenic links between fibronectin (Fn) fragmentation and the inflammatory response in chronic joint disease. METHODS: Scientific papers involving studies of Fn fragments and inflammatory processes important in the pathogenesis of arthritis, including chondrolysis, synoviocyte growth and adhesion, polymorphonuclear leukocyte (PMN) and monocyte function, proteolysis, and immune complex activation were reviewed. In addition, reports identifying Fn fragments in synovial fluid (SF) were assessed. RESULTS: A series of Fn fragments have been identified in arthritic SF by several investigators. Fn and fragments ranging from 30 to 200 kd are present in elevated concentrations in inflammatory SF. SF Fn fragments display reduced affinity for fibrin and collagen. The 29- and 50-kd amino terminal fragments mediate release of proteoglycan from articular cartilage by RGD-independent mechanisms. Fn fragments can induce fibroblast gene expression of metalloproteinases or can act as proteinases themselves. A 90-kd plasmin generated fragment possesses homology with streptokinase. Fragments mediate PMN chemotaxis and enhance proliferation of CD4+ lymphocytes as well as binding to the C1q component of complement and influencing the behavior of immune complexes. CONCLUSIONS: Fn fragments can be functionally and biochemically characterized in diseased SF. Modification of fragment formation and inhibition of fragment function may have potential therapeutic value in the interruption of chronic synovial inflammation.

Neutralization of tumor necrosis factor activity shortly after the onset of dendritic cell hematopoiesis reveals a novel mechanism for the selective expansion of the CD14-dependent dendritic cell pathway.

The CD14-dependent and -independent dendritic cell (DC) pathways are instituted simultaneously when CD34(+) progenitor cells are treated with granulocyte-macrophage colony-stimulating factor (GM-CSF)/tumor necrosis factor (TNF) +/- stem cell factor (SCF) (GTS). If TNF activity is neutralized within 48 hours of cytokine exposure, DC development is halted and myelogranulocytic hematopoiesis takes place. In this study, we show that disruption of TNF activity at a later time point produced a distinct alteration within the DC system. Instead of downregulating DC development, treatment of GTS cultures with antibodies to TNF (anti-TNF) on day 3 provoked the selective expansion of the CD14-dependent (monocyte) DC pathway from progenitor cell populations lacking CD14 and CD1a. After an initial decrease in proliferation, anti-TNF produced a rebound in cell growth that yielded intermediate myeloid progenitors exhibiting CD14-dependent DC differentiation potential and CD14(+)CD1a+ DC precursors. Cultures enriched in CD14-dependent DCs were more potent stimulators of a mixed leukocyte reaction, compared with control GTS cultures containing both types of DCs. The intermediate progenitors expanded in the presence of anti-TNF were CD115(+)CD33(+)DR+, long-lived, and displayed clonogenic potential in methylcellulose. When exposed to the appropriate cytokine combinations, these cells yielded granulocytes, monocytes, and CD14-dependent DCs. Antigen-presenting function was acquired only when DC maturation was induced from these myelodendritic progenitors with GM-CSF + interleukin-4 or GTS. These studies show a novel mechanism by which TNF regulates the DC system, as well as providing a strategy for the amplification of the CD14-dependent DC pathway from immature progenitors. Although TNF is required to ensure the institution of DC hematopoiesis from CD34(+) progenitor cells, its activity on a later progenitor appears to limit the development of CD14-dependent DCs.

Rheumatologic disorders in women.

This article reviews common rheumatic diseases that most frequently occur in women including fibromyalgia, rheumatoid arthritis, Sjogren's syndrome, systemic lupus erythematosus and the antiphospholipid antibody syndrome. Many of these women are of child bearing potential and special considerations concerning pregnancy often arise. Rheumatic conditions that frequently affect older women such as osteoarthritis and polymyalgia rheumatica are discussed as well. Osteoporosis, which has emerged as a significant women's health issue, is also reviewed.

In vitro expansion of CD13+CD33+ dendritic cell precursors from multipotent progenitors is regulated by a discrete fas-mediated apoptotic schedule.

We provide new information on how apoptosis regulates the expansion and survival of dendritic cell (DC) elements during in vitro hematopoiesis. Functionally distinct apoptotic schedules were associated with different phases of DC development when multipotent CD34+ progenitor cells were treated with GM-CSF + TNF +/- SCF (c-kit ligand). During early phases of growth, unselected progenitors underwent apoptosis. During intermediate stages, high levels of apoptosis resulted in the preferential selection of DC precursors, as revealed by the massive expansion of DR+CD33+CD13+ cells. Late apoptosis was associated with the death of mature DCs. Apoptotic events surrounding the earlier periods were related to the exogenous addition of TNF-alpha and appeared to be mediated by fas. In contrast, those events associated with terminally differentiated DCs were fas independent because there was no correlation between fas expression and cell death. The bcl-2 protein family appeared to confer resistance to apoptotic death, as revealed by the high levels of bcl-2 and bclxL during peak DC development and in long-term DC cultures. We demonstrate that activation of distinct apoptotic programs regulates DC development and homeostasis. Although suppression of apoptosis may prolong the survival of late DC elements, an earlier apoptotic schedule appears to be required for the selective expansion of DC elements from multipotent progenitors. Our data also provides insight into the mechanism(s) of myeloid lineage selection by cytokines such as TNF-alpha, which may promote both cell death and survival.

The association of malignancy with rheumatic and connective tissue diseases.

This article reviews the associations of cancer with rheumatic diseases. Recent epidemiologic data linking the autoimmune connective tissue diseases with malignancy will be emphasized. Reports linking the occurrence of malignancy with rheumatoid arthritis, systemic lupus erythematosus, idiopathic inflammatory myopathy, scleroderma, and vasculitis are described. The effect of immunomodulating drugs in the development of malignancy is discussed. Mechanisms potentially responsible for malignant transformation in the lymphoproliferation of Sjogren's syndrome are described. The relationship of gout to cancer as well as direct effects of cancer on the musculoskeletal system is also reviewed.

Distinct alterations in lineage committed progenitor cells exist in the peripheral blood of patients with rheumatoid arthritis and primary Sjogren's syndrome.

OBJECTIVE: Due to the elevated levels of hematopoietically active cytokines such as tumor necrosis factor (TNF) and granulocyte macrophage colony stimulating factor (GMCSF) in rheumatoid arthritis (RA) serum and synovium, the increased bone marrow activity in RA, and the effectiveness of GMCSF in mobilizing progenitor cell release from the bone marrow into the periphery, we hypothesized that hematopoietic progenitors are altered in the peripheral blood (PB) of patients with RA. METHODS: Flow cytometry assisted cell surface analysis was employed to compare the distribution of myeloid (CD34+CD33+), B lymphoid (CD34+CD10+), and erythroid (CD34+CD71+) committed progenitor cell subsets in the PB of healthy controls and patients with RA. Since RA and Sjogren's syndrome (SS) are related autoimmune disorders, primary SS PB was also investigated. RESULTS: Only those patients with RA exhibiting clinically active disease (RA-A) demonstrated increases in myeloid and B lymphoid progenitor cell subsets. Growth of RA-A progenitors in cytokines promoting myelopoiesis (GMCSF, TNF, stem cell factor) produced increased monocyte and dendritic cell progeny, in support of the flow cytometry data. Lineage committed (CD34+CD38+) progenitors were increased in SS PB (p <0.03). However, these did not correlate with either the myeloid, erythroid, or B lymphoid lineages. CONCLUSION: Distinct alterations in the distribution of PB progenitors are present in RA and primary SS. Since progenitor cells retain a proliferative capacity, their infiltration into the synovial/glandular environment may contribute to the accumulation of inflammatory cells within these sites. We propose that PB progenitors enter the diseased microenvironment through similar mechanisms as mature hematopoietic elements.

Endogenously produced interleukin 6 is an accessory cytokine for dendritic cell hematopoiesis.

The aim of this study was to investigate the role of interleukin 6 (IL-6) in normal dendritic cell (DC) hematopoiesis. We used an enzyme-linked immunosorbent assay to quantitate IL-6 levels in CD34+ progenitor cell cultures favoring monocyte (mono) development versus those supporting mono-DC growth, and studied the neutralizing effects of alphaIL-6 antibody on DC hematopoiesis. IL6 levels in mono cultures (GM-CSF alone) were detected by day 4 and remained constant (approximately 100+ pg/ml) for 18 days. In mono-DC cultures, higher IL-6 levels correlated with DC content and development. Short-term mono-DC cultures initiated with GM-CSF + tumor necrosis factor (TNF) + stem cell factor (SCF) exhibited increases in IL-6 level until day 11 (peak DC growth). By day 18, the levels had declined and cells expressing typical DC features were no longer present. Long-term mono-DC cultures sustained with GM-CSF + TNF + SCF contained the highest IL-6 levels (671 pg/ml) on day 11. In these cultures, DCs and higher IL-6 levels persisted beyond 18 days. Anti-IL-6 profoundly inhibited cell proliferation associated with DC hematopoiesis when added on days 0, 2 and 5 to GM-CSF + TNF + SCF cultures, indicating that various stages of mono-DC development rely on IL-6. There was no reduction in the T cell response when alphaIL-6 was added to mixed leukocyte reaction cultures containing mature DCs as stimulators. Thus, alphaIL-6 appears to downregulate developmental processes associated with optimal mono-DC growth, but not the effector functions of mature DCs. These studies substantiate the importance of IL-6 as a secondary cytokine during DC development and provide insight into another control point in the DC pathway.

Fever in rheumatic and autoimmune disease.

This article reviews the most common clinical conditions presenting with fever and musculoskeletal symptoms and attempts to categorize these disorders according to general etiologic categories as an aid to differential diagnosis. Although a substantial armamentarium of serologic, immunologic, and molecular laboratory studies have been developed and are available to the clinician, the most important data are obtained from a careful history and physical examination with emphasis on the musculoskeletal system.

Quantitation and distribution of vitronectin in synovial fluid and tissue of patients with rheumatic disease.

OBJECTIVE: Our study was undertaken to determine the quantity and pattern of distribution of vitronectin (Vn) in the synovial fluid and tissue of patients with rheumatic disease. METHODS: We quantitated synovial fluid Vn levels in 37 patients (17 with rheumatoid arthritis (RA), 12 with crystal induced arthritis (CIA), and 8 with osteoarthritis (OA)) using a competitive-binding ELISA: Immunofluorescence studies were performed on synovial pannus tissue specimens from 3 RA patients. SDS-PAGE analysis of the synovial fluids was performed to demonstrate the molecular forms of Vn present in inflammatory and noninflammatory synovial fluids. Albumin levels of synovial fluids were determined using an automated chemistry analyzer. RESULTS: Immunoreactive Vn was detected in 36 of 37 synovial fluid specimens examined, over a wide range of dilutions. Concentrations of Vn in inflammatory synovial fluid were significantly elevated compared to non-inflammatory synovial fluid and normal human plasma (NHP). Immunofluorescence studies revealed immunoreactive Vn most heavily concentrated in the lining layers of RA pannus tissue. Similar to NHP, molecular forms of Vn were heterogeneous in the synovial fluid; however, the inflammatory milieu appears to predispose Vn to cleavage at its protease-sensitive site. Overall there was a positive correlation of synovial fluid Vn to albumin. CIA and OA revealed a very strong relationship, whereas RA synovial fluid Vn levels correlated poorly to the levels of albumin. CONCLUSION: Vitronectin is present in synovial fluid. Levels are significantly enhanced in the inflamed joint and in the RA synovial lining, where it may influence cell adhesion and modulate tissue repair.

Stem cell factor augments tumor necrosis factor-granulocyte-macrophage colony-stimulating factor-mediated dendritic cell hematopoiesis.

We describe the effects of stem cell factor (SCF) on the dendritic cell (DC) pathway and provide evidence for the existence of a post granulocyte-macrophage colony-forming unit (GM-CFU) DC progenitor. When employed with cytokines regulating DC development (tumor necrosis factor [TNF] + GM colony-stimulating factor [GM-CSF]), SCF increased the size of monocyte (mono) and mono-DC colonies arising from cord blood CD34+ progenitor cells. The overall plating efficiency of these colonies increased approximately threefold, as compared with growth in TNF + GM-CSF. Most (approximately 70%) of the CFUs were mono-DC CFU, and SCF did not alter the proportion of mono-DC CFU to mono-CFU obtained with TNF + GM-CSF alone. Proliferation, as measured by thymidine uptake and manual cell counts, at least doubled and occurred earlier (by day 4). In long-term cultures established with TNF + GM-CSF + SCF, high levels of proliferation were prolonged for up to three weeks. These were associated with extended DC development and the capacity to form 2 degree mono-DC colonies. There was no induction of polymorphonuclear (PMN) cells in 2 degree cultures treated with either GM-CSF, GM-CSF + SCF or GM-CSF + granulocyte CSF (G-CSF), implying that the DC progenitor being replated was post GM-CFU. DC progeny arising in the presence of SCF exhibited typical DC features including: the lack of nonspecific esterase and phagocytic activity, the presence of class II major histocompatibility complex (MHC) antigens, the absence of CD14 antigens, and the ability to induce a potent mixed leukocyte reaction. Thus, SCF augments DC growth from progenitor cells without altering the developmental commitment instituted by TNF + GM-CSF. This enhancement follows the same general mechanisms previously reported for SCF-mediated lineage enhancement, i.e., increased colony size, number and plating capacity.