Cardiovascular disease in autoimmune rheumatic diseases

Various autoimmune rheumatic diseases (ARDs), including rheumatoid arthritis, spondyloarthritis, vasculitis and systemic lupus erythematosus, are associated with premature atherosclerosis. However, premature atherosclerosis has not been uniformly observed in systemic sclerosis. Furthermore, although experimental models of atherosclerosis support the role of antiphospholipid antibodies in atherosclerosis, there is no clear evidence of premature atherosclerosis in antiphospholipid syndrome (APA). Ischemic events in APA are more likely to be caused by pro-thrombotic state than by enhanced atherosclerosis.     

Interstitial lung disease in systemic autoimmune rheumatic diseases: a comprehensive review

Background: Interstitial lung diseases (ILDs) are among the most serious complications associated with systemic rheumatic diseases, and lead to significant morbidity and mortality; they may also be the first manifestation of connective tissue diseases (CTDs). The aim of this narrative review is to summarise the data concerning the pathogenesis of CTD/ILD and its distinguishing features in different rheumatic diseseas.

Areas covered: The pathogenesis, clinical aspects and treatment of ILD associated with rheumatic systemic diseases and CTDs were reviewed by searching the PubMed, Medline, and Cochrane Library databases for papers published between 1995 and February 2017 using combinations of words or terms. Articles not written in English were excluded.

Expert commentary: The management of CTD–ILD is challenging because of the lack of robust data regarding the treatments used, the heterogeneity of the diseases themselves, and the scarcity of well-defined outcome measures. Treatment decisions are often made clinically on the basis of functional, radiographic progression, and exacerbating factors such as age and the burden of comorbidities. Given the complexities of diagnosis and the paucity of treatment trials, the management of CTD patients with ILD requires multidisciplinary collaboration between rheumatologists and pulmonologists in CTD-ILD clinics.     

Interaction of pregnancy and autoimmune rheumatic disease

During pregnancy, the fetus represents a natural allograft that is not normally rejected. While the maternal immune system retains the ability to respond to foreign antigens, tolerance mechanisms are up-regulated to protect the fetus from immunologic attacks by the mother. The profound immunologic adaptations during and after pregnancy do influence maternal autoimmune rheumatic diseases in several ways. One is triggering the onset of a rheumatic disease in the post partum period, the other influencing disease activity of established rheumatic disease. The review will discuss the mechanisms of increased susceptibility of rheumatoid arthritis (RA) in the first year post partum with a specific emphasis on the role of fetal cells or antigens persisting in the maternal circulation (so called microchimerism). Furthermore, the different influences of pregnancy on established rheumatic diseases will be highlighted. A marked beneficial effect of pregnancy is observed on RA whereas several other rheumatic diseases as ankylosing spondylitis (AS) and systemic lupus erythematosus (SLE) show either no particular effect or an aggravation of symptoms during pregnancy. Differences emerging in regard to modulation of disease symptoms during pregnancy seem related to response to hormones, the type of cytokine profile and immune response prevailing as well as further downstream interactions of molecular pathways that are important in disease pathogenesis.     

Modelling experimental uveitis: barrier effects in autoimmune disease

Objective and design

A mathematical analysis of leukocytes accumulating in experimental autoimmune uveitis (EAU), using ordinary differential equations (ODEs) and incorporating a barrier to cell traffic.

Materials and subjects

Data from an analysis of the kinetics of cell accumulation within the eye during EAU.

Methods

We applied a well-established mathematical approach that uses ODEs to describe the behaviour of cells on both sides of the blood–retinal barrier and compared data from the mathematical model with experimental data from animals with EAU.

Results

The presence of the barrier is critical to the ability of the model to qualitatively reproduce the experimental data. However, barrier breakdown is not sufficient to produce a surge of cells into the eye, which depends also on asymmetry in the rates at which cells can penetrate the barrier. Antigen-presenting cell (APC) generation also plays a critical role and we can derive from the model the ratio for APC production under inflammatory conditions relative to production in the resting state, which has a value that agrees closely with that found by experiment.

Conclusions

Asymmetric trafficking and the dynamics of APC production play an important role in the dynamics of cell accumulation in EAU.     

Autoantibodies and overlap syndromes in autoimmune rheumatic disease

Many patients diagnosed with autoimmune rheumatic disease cannot be categorised easily into one of the established clinical entities such as systemic lupus erythematosus, dermatomyositis, or systemic sclerosis. The term "overlap syndrome" has been increasingly used to identify such patients and is useful in terms of clarifying prognosis and facilitating disease management. This article reviews overlap syndrome in autoimmune rheumatic disease, with particular emphasis on the associated serological markers.     

Anticardiolipin antibodies in unselected autoimmune rheumatic disease patients

Quantitative determination of IgG and IgM antibodies to cardiolipin (anti-CL) was performed with a newly developed sensitive and specific ELISA method. We studied a cohort of 361 unselected patients with various autoimmune rheumatic diseases (ARD), 69 patients with thromboembolic phenomena (TEP) unassociated with ARD, and 267 healthy blood donors (HBD). Anti-CL of at least one immunoglobulin class were found in 42 (11.6%) of the ARD patients, in 3 (4.3%) of the TEP patients (2 with myocardial infarction and 1 with pulmonary emboli), and in 6 (2.3%) of the HBD. In ARD patients anti-CL were more prevalent in patients with systemic lupus erythematosus (SLE) and overlap syndromes. Significant correlations included CNS involvement (particularly seizures) and features of immune hyperreactivity (splenomegaly-lymphadenopathy, ANA, and antibodies to Ro(SSA), U1-nRNP, and double-stranded DNA). No statistical correlation could be demonstrated between the presence of anti-CL and thrombotic events, hematologic disorders, or recurrent abortions in the ARD patients.     

Molecular mimicry in the autoimmune pathogenesis of rheumatic heart disease

Molecular mimicry is a hallmark of the pathogenesis of rheumatic fever where the streptococcal group A carbohydrate epitope, N-acetyl glucosamine, and the α-helical coiled-coil streptococcal M protein structurally mimic cardiac myosin in the human disease, rheumatic carditis, and in animal models immunized with streptococcal M protein and cardiac myosin. Recent studies have unraveled the potential pathogenic mechanisms by which the immune response against the group A streptococcus attacks the rheumatic valve leading to chronic rheumatic heart disease. Both B- and T-cell responses are involved in the process, and evidence for the hypotheses of molecular mimicry and epitope spreading are reviewed.     

IL-35: a new immunomodulator in autoimmune rheumatic diseases

IL-35 is a relatively new cytokine that emerges as an important immunomodulator. IL-35 belongs to IL-12 cytokine family that includes IL-12, IL-23, IL-27, and IL-35. These cytokines are heterodimers that share subunits and their receptors also share subunits. Whereas IL-12 and IL-23 are clearly proinflammatory cytokines, the role of IL-35 is less clear. In mice, IL-35 appears to be anti-inflammatory and to protect from autoimmune inflammatory diseases. IL-35 induces the expansion of a subset of regulatory T cells (Tregs) and Bregs and mediates their suppressive function and inhibits Th17 cells. It also upregulates osteoprotegerin and suppresses RANKL, thus inhibiting bone resorption. In autoimmune rheumatic diseases, findings are conflicting, although in systemic lupus erythematosus, there is reduced function of IL-35. In psoriatic arthritis, a disease characterized by bone erosion and bone formation in peripheral joints and bone formation in spinal joints, serum levels of IL-35 were found increased in one study. Further data are required to define the exact role of IL-35 in human autoimmune rheumatic diseases.     

Molecular mimicry in the autoimmune pathogenesis of rheumatic heart disease

Molecular mimicry is a hallmark of the pathogenesis of rheumatic fever where the streptococcal group A carbohydrate epitope, N-acetyl glucosamine, and the a-helical coiled-coil streptococcal M protein structurally mimic cardiac myosin in the human disease, rheumatic carditis, and in animal models immunized with streptococcal M protein and cardiac myosin. Recent studies have unraveled the potential pathogenic mechanisms by which the immune response against the group A streptococcus attacks the rheumatic valve leading to chronic rheumatic heart disease. Both B- and T-cell responses are involved in the process, and evidence for the hypotheses of molecular mimicry and epitope spreading are reviewed.     

Vaccination and autoimmune rheumatic diseases

Patients with autoimmune rheumatic diseases are at increased risk of developing infections. However, concerns about the safety and the immunogenicity of vaccines in these patients limited their use. Most of the data against the use of vaccines come from the reported cases of previously healthy individuals who presented the onset of rheumatic diseases after immunization, nevertheless a causal relationship has not been established. During the past few decades influenza and pneumococcal vaccines, administered to patients with systemic lupus erythematosus, were found to be safe and, generally, serologically effective, even though there is the possibility of inadequate response, especially in patients receiving immunosuppressive agents. In patients with rheumatoid arthritis influenza and pneumococcal vaccines can be considered safe and immunogenic in most cases. Treatment with TNFalpha blocking agents did not appear to impair the immune response.     

Italian multicentre study for application of a diagnostic algorithm in autoantibody testing for autoimmune rheumatic disease: conclusive results

Aim

The presence of specific auto-antibodies in serum (i.e., antinuclear antibodies or ANA, anti-extractable nuclear antigens or anti-ENA, and anti-double stranded DNA or anti-dsDNA ) is one of the major criteria in the diagnostics of Autoimmune Rheumatic Disease. As such, the request for these tests has grown exponentially in laboratory practice. The aim of this study is to describe the implementation of a joint laboratory-clinics guideline for reducing clinically inappropriate requests for autoantibody testing in a broad geographic area (Parma, Modena, Piacenza, Reggio-Emilia) for the diagnosis of Autoimmune Rheumatic Disease.

Methods

This study, supported by a Regional grant for innovative research projects started in January 2008, is an observational research aimed at comparing the number of ANA, anti-dsDNA and anti-ENA testing as well as the percentage of positive test results before and after implementation of the diagnostic algorithm in hospitalized patients. A multidisciplinary team consisting of clinical immunologist and laboratory scientists was established, with the aim of collecting and analysing diagnostic criteria, clinical needs, laboratory report formats, analytical procedures, as well as the number of tests performed. The laboratory results and the clinical protocol were both validated by data emerging from the clinical follow-up studies.

Results

A joint guideline for auto-antibody testing, placing ANA test at the first level, has been developed and implemented since January 2009. The results for the period January–June 2009 (12,738 tests) were compared with those of the same period in 2008 (13,067 tests). A significant reduction in the number of anti-dsDNA (− 26%) and anti-ENA (− 15%) was observed. The percentage of second-level tests positivity after implementation of the diagnostic protocol had also consistently increased for both ENA (13% vs 17%) and dsDNA (9% vs 11%).

Discussion

The development and implementation of algorithms for the diagnostics of Autoimmune Rheumatic Disease in hospitalized patients was associated with a reduction in the number of second-level tests, but also with an increased diagnostic specificity. This outcome attests that close collaboration and audit between clinicians, laboratory specialists and healthcare services is effective to develop efficient diagnostic algorithms for both hospitalized patients and outpatients.     

Air pollution in autoimmune rheumatic diseases: A review

Air pollution consists of a heterogeneous mixture of gasses and particles that include carbon monoxide, nitrates, sulfur dioxide, ozone, lead, toxic by-product of tobacco smoke and particulate matter. Oxidative stress and inflammation induced by inhaled pollutants may result in acute and chronic disorders in the respiratory system, as well as contribute to a state of systemic inflammation and autoimmunity. This paper reviews the mechanisms of air contaminants influencing the immune response and autoimmunity, and it focuses on studies of inhaled pollutants triggering and/or exacerbating rheumatic diseases in cities around the world. Remarkably, environmental factors contribute to the onset of autoimmune diseases, especially smoking and occupational exposure to silica in rheumatoid arthritis and systemic lupus erythematosus. Other diseases such as scleroderma may be triggered by the inhalation of chemical solvents, herbicides and silica. Likewise, primary vasculitis associated with anti-neutrophil cytoplasmic antibody (ANCA) may be triggered by silica exposure. Only few studies showed that air pollutants could trigger or exacerbate juvenile idiopathic arthritis and systemic lupus erythematosus. In contrast, no studies of tropospheric pollution triggering inflammatory myopathies and spondyloarthropathies were carried out. In conclusion, air pollution is one of the environmental factors involved in systemic inflammation and autoimmunity. Further studies are needed in order to evaluate air pollutants and their potentially serious effects on autoimmune rheumatic diseases and the mechanisms involved in the onset and the exacerbation of these diseases.     

Pulmonary hypertension in autoimmune rheumatic diseases

Arterial pulmonary hypertension (PH) might be a complication of some autoimmune rheumatic diseases, specially systemic sclerosis. This form of arterial PH is indistinguishable from primary PH, characterised by the presence of plexiform lesions. Although for many years plexiform lesions have been considered end-stage scarring lesions, they are composed by actively proliferating endothelial cells that share many features with cancer cells. Endothelial cells within plexiform lesions in all forms of arterial PH show a decrease in the expression of vasodilator and anti-proliferative factors, and an increase in the expression of vasoconstrictor and angiogenic and mitogenic factors. These cells also show important alterations in growth and apoptosis key regulatory genes. Plexiform lesions are surrounded by inflammatory cell infiltrates, probably providing cytokines that may contribute to the endothelial cell proliferative process. All these data suggest that arterial PH might be seen as a proliferative endothelial cell process, which would open new therapeutic approaches for this devastating disease.     

Accelerated atherogenesis in autoimmune rheumatic diseases

The observation that systemic inflammatory rheumatic diseases such as rheumatoid arthritis (RA) are associated with a significantly increased rate of cardiovascular disease, which often occurs at a younger age than in the normal population, is particularly important given the increasing interest in the role of inflammation in atherogenesis in the general population. This review examines the accumulating evidence for accelerated atherogenesis of RA and updates the hypothesis that vasculitis plays a major role in this. Endothelial dysfunction (ECD), widely regarded as initial lesion in atherogenesis, has been shown to occur commonly in primary vasculitis. This ECD is a diffuse event, demonstrable in more than one vascular bed. It is not simply due to scarring in the vessel wall, related to the focal inflammation of the underlying vasculitis, since it may be reversed by suppression of the immune inflammation. However, the mechanisms for this ECD differ from that of the primary vasculitis. Preliminary evidence suggests that inflammatory mediators such as CRP, TNF, or sphingolipids may be involved. The diffuse ECD of vasculitis may have important consequences for both the progression of the primary disease and for cardiovascular events. A model for the role of vasculitis-induced ECD in the accelerated atherogenesis of rheumatic diseases is presented. These concepts are discussed together with the messages they suggest for 'idiopathic' atherosclerosis in the general population.     

Retroviruses and autoimmune rheumatic diseases.

In autoimmune rheumatic diseases, retroviruses have been repeatedly discussed as important etiologic factors. However, despite a considerable amount of indirect evidence that retroviruses might indeed be involved in triggering or perpetuating autoimmune rheumatic diseases, clear cut direct evidence is still missing. Studies on arthropathies associated with HIV-1 or HTLV-1 infection as well as new experimental animal models like the Tax transgene mice and new data from the MLR/lpr mouse model might help to answer the questions how and by what mechanisms retroviral infection may lead to autoimmune rheumatic diseases. From data obtained in the MLR/lpr mouse it seems obvious that a potential link of retroviruses, apoptosis and autogenes to autoimmune diseases opens exciting new approaches to the study of rheumatic disease pathogenesis.     

Immunoglobulin replacement for secondary immunodeficiency after B-cell targeted therapies in autoimmune rheumatic disease: Systematic literature review

Background

Consensus guidelines are not available for the use of immunoglobulin replacement therapy (IGRT) in patients developing iatrogenic secondary antibody deficiency following B-cell targeted therapy (BCTT) in autoimmune rheumatic disease.

Epigenetics,pregnancy and autoimmune rheumatic diseases

Autoimmune rheumatic diseases (ARDs) are chronic conditions with a striking female predominance, frequently affecting women of childbearing age.Sex hormones and gender dimorphism of immune response are major determinants in the multifactorial pathogenesis of ARDs, with significant implications throughout reproductive life. Particularly, pregnancy represents a challenging condition in the context of autoimmunity, baring profound hormonal and immunologic changes, which are responsible for the bi-directional interaction between ARDs outcome and pregnancy course.In the latest years epigenetics has proven to be an important player in ARDs pathogenesis, finely modulating major immune functions and variably tuning the significant gender effects in autoimmunity. Additionally, epigenetics is a recognised influencer of the physiological dynamic modifications occurring during pregnancy.Still, there is currently little evidence on the pregnancy-related epigenetic modulation of immune response in ARDs patients.This review aims to overview the current knowledge of the role of epigenetics in the context of autoimmunity, as well as during physiologic and pathologic pregnancy, discussing under-regarded aspects in the interplay between ARDs and pregnancy pathology. The outline of a new ongoing European project will be presented.     

B cell depletion in autoimmune rheumatic diseases

Rituximab is a chimeric mouse-human monoclonal antibody, which binds to CD20, a B cell surface marker, leading to cell death by complement induced lysis and apoptosis. Since the introduction of this drug in the treatment of non-Hodgkin lymphoma, its applications have been extended to autoimmune diseases. This review summarizes the actual possible uses of this novel immune system targeted drug, and explains the mechanism of B cell depletion in autoimmune diseases.