Experimental reproduction of skin lesions in lupus erythematosus by UVA and UVB radiation

Raman spectroscopy and mass spectrometry identifies a unique group of epidermal lipids in active discoid lupus erythematosus

Discoid lupus erythematosus (DLE) is the most common form of cutaneous lupus1. It can cause permanent scarring. The pathophysiology of is not fully understood. Plasmacytoid dendritic cells are found in close association with apoptotic keratinocytes inferring close cellular signalling. Matrix Associated Laser Desorption Ionisation (MALDI) combined with Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS) is an exquisitely sensitive combination to examine disease processes at the cellular and molecular level. Active areas of discoid lupus erythematosus were compared with normal perilesional skin using MALDI combined with FT-ICR-MS. A unique set of biomarkers, including epidermal lipids is identified in active discoid lupus. These were assigned as sphingomyelins, phospholipids and ceramides. Additionally, increased levels of proteins from the keratin, and small proline rich family, and aromatic amino acids (tryptophan, phenylalanine, and tyrosine) in the epidermis are observed. These techniques, applied to punch biopsies of the skin, have shown a distinctive lipid profile of active discoid lupus. This profile may indicate specific lipid signalling pathways. Lipid rich microdomains (known as lipid rafts) are involved in cell signalling and lipid abnormalities have been described with systemic lupus erythematosus which correlate with disease activity.

Differential impact of environmental factors on systemic and localized autoimmunity

The influence of environmental factors on the development of autoimmune disease is being broadly investigated to better understand the multifactorial nature of autoimmune pathogenesis and to identify potential areas of intervention. Areas of particular interest include the influence of lifestyle, nutrition, and vitamin deficiencies on autoimmunity and chronic inflammation. In this review, we discuss how particular lifestyles and dietary patterns may contribute to or modulate autoimmunity. We explored this concept through a spectrum of several autoimmune diseases including Multiple Sclerosis (MS), Systemic Lupus Erythematosus (SLE) and Alopecia Areata (AA) affecting the central nervous system, whole body, and the hair follicles, respectively. A clear commonality between the autoimmune conditions of interest here is low Vitamin D, a well-researched hormone in the context of autoimmunity with pleiotropic immunomodulatory and anti-inflammatory effects. While low levels are often correlated with disease activity and progression in MS and AA, the relationship is less clear in SLE. Despite strong associations with autoimmunity, we lack conclusive evidence which elucidates its role in contributing to pathogenesis or simply as a result of chronic inflammation. In a similar vein, other vitamins impacting the development and course of these diseases are explored in this review, and overall diet and lifestyle. Recent work exploring the effects of dietary interventions on MS showed that a balanced diet was linked to improvement in clinical parameters, comorbid conditions, and overall quality of life for patients. In patients with MS, SLE and AA, certain diets and supplements are linked to lower incidence and improved symptoms. Conversely, obesity during adolescence was linked with higher incidence of MS while in SLE it was associated with organ damage. Autoimmunity is thought to emerge from the complex interplay between environmental factors and genetic background. Although the scope of this review focuses on environmental factors, it is imperative to elaborate the interaction between genetic susceptibility and environment due to the multifactorial origin of these disease. Here, we offer a comprehensive review about the influence of recent environmental and lifestyle factors on these autoimmune diseases and potential translation into therapeutic interventions.

Review on photoprotection: a clinician’s guide to the ingredients, characteristics, adverse effects, and disease-specific benefits of chemical and physical sunscreen compounds

Photoprotection is a critical health prevention strategy to reduce the deleterious effects of ultraviolet radiation (UVR) and visible light (VL). Methods of photoprotection are reviewed in this paper, with an emphasis on sunscreen. The most appropriate sunscreen formulation for personal use depends on several factors. Active sunscreen ingredients vary in their protective effect over the UVR and VL spectrum. There are dermatologic diseases that cause photosensitivity or that are aggravated by a particular action spectrum. In these situations, sunscreen suggestions can address the specific concern. Sunscreen does not represent a single entity. Appropriate personalized sunscreen selection is critical to improve compliance and clinical outcomes. Health care providers can facilitate informed product selection with awareness of evolving sunscreen formulations and counseling patients on appropriate use. This review aims to summarize different forms of photoprotection, discuss absorption of sunscreen ingredients, possible adverse effects, and disease-specific preferences for chemical, physical or oral agents that may decrease UVR and VL harmful effects.

Innate immune activation as cofactor in pemphigus disease manifestation

Molecular mechanisms underlying auto-antibody-induced acantholysis in pemphigus vulgaris are subject of current research to date. To decipher the discrepancy between ubiquitous antibody binding to the epidermal desmosomes, but discontinuous disease manifestation, we were able to identify Ultraviolet A (UVA) as a cofactor for acantholysis. UVA induces interleukin (IL)-1 secretion in keratinocytes, mirroring innate immune system activation. In an in vitro keratinocyte dissociation assay increased fragmentation was observed when UVA was added to anti-Desmoglein 3 Immunoglobulins (anti-Dsg3 IgG). These results were confirmed in skin explants where UVA enhanced anti-Dsg3-mediated loss of epidermal adhesion. The UVA-mediated effect was blocked in vitro by the pan-caspase-inhibitor zVAD-fmk. Thus, we introduce UVA as a caspase-dependent exogenous cofactor for acantholysis which suggests that local innate immune responses largely contribute to overt clinical blister formation upon autoantibody binding to epidermal cells in pemphigus vulgaris.

Endoplasmic Reticulum Stress, Oxidative Stress, and Rheumatic Diseases

Background: The endoplasmic reticulum (ER) is a multi-functional organelle responsible for cellular homeostasis, protein synthesis, folding and secretion. It has been increasingly recognized that the loss of ER homeostasis plays a central role in the development of autoimmune inflammatory disorders, such as rheumatic diseases. Purpose/Main contents: Here, we review current knowledge of the contribution of ER stress to the pathogenesis of rheumatic diseases, with a focus on rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). We also review the interplay between protein folding and formation of reactive oxygen species (ROS), where ER stress induces oxidative stress (OS), which further aggravates the accumulation of misfolded proteins and oxidation, in a vicious cycle. Intervention studies targeting ER stress and oxidative stress in the context of rheumatic diseases are also reviewed. Conclusions: Loss of ER homeostasis is a significant factor in the pathogeneses of RA and SLE. Targeting ER stress, unfolded protein response (UPR) pathways and oxidative stress in these diseases both in vitro and in animal models have shown promising results and deserve further investigation.

Photodiagnostic services in the UK and Republic of Ireland: a British Photodermatology Group Workshop Report

BACKGROUND

Photodiagnostic investigations are essential for the accurate diagnosis of abnormal cutaneous photosensitivity and provide important information for the management of patients with photodermatoses (cutaneous photosensitivity disorders). Although photodiagnosis has been undertaken since the early 1970s, specialist services in the United Kingdom (UK) and Republic of Ireland are limited and there is no formal guidance on diagnostic approach. Indeed, there is a limited literature in this area of methodology and diagnostic practice.

OBJECTIVES

The primary objective was to undertake a British Photodermatology Group Workshop to review the role and activities of specialist centres in the UK and Republic of Ireland in order to ascertain whether there were consensus practices. Secondary objectives were to identify key priorities for service, training and research.

METHODS

An initial detailed survey review of current activities was undertaken prior to the Workshop and data from this survey were used to inform discussion at the Workshop, which was attended by key photodermatology experts from the UK and Republic of Ireland.

RESULTS/CONCLUSIONS

We have undertaken a detailed review of current Photodiagnostic Services in the UK and Republic of Ireland and report on our findings from the 12 centres and we have identified key areas of consensus practice. This is an important step in the process of standardising and optimising procedures and protocols and defining minimum clinical standards for photodiagnostic investigations, which are of such diagnostic importance in Dermatology.

Akt activation-dependent protective effect of wild ginseng adventitious root protein against UVA-induced NIH-3T3 cell damage

Prolonged skin exposure to ultraviolet radiation can lead to development of several acute and chronic diseases, with UVA exposure considered a primary cause of dermal photodamage. We prepared a wild ginseng adventitious root extract (ARE) that could alleviate UVA irradiation-induced NIH-3T3 cell viability decline. After employing a series of purification methods to isolate main active components of ARE, adventitious root protein mixture (ARP) was identified then tested for protective effects against UVA irradiation-induced NIH-3T3 cell damage. The results showed that ARP treatment significantly reduced UVA-induced cell viability decline and confirmed that the active constituent of ARP was the protein, since proteolytic hydrolysis and heat treatment each eliminated ARP protective activity. Moreover, ARP treatment markedly inhibited UVA-induced apoptosis, cell cycle arrest and DNA fragmentation, while also significantly reversing UVA effects (elevated Bax levels, reduced Bcl-2 expression) by reducing Bax levels and increasing Bcl-2 expression. Mechanistically, ARP promoted Akt phosphorylation regardless of UVA exposure, thus confirming ARP resistance to inactivation by UVA light. Notably, in the presence of Akt inhibitor SC0227, ARP could no longer counteract UVA-induced cell viability decline and DNA fragmentation. Additionally, our results demonstrated that ARP treatment protected UVA-irradiated NIH-3T3 cells by preventing UVA-induced reduction of collagen-I expression. Taken together, these results suggest that ARP treatment of NIH-3T3 cells effectively mitigated UVA-induced cell viability decline by activating intracellular Akt to reduce UVA-induced DNA damage, leading to reduced rates of apoptosis and cell cycle arrest after UVA exposure and restoring collagen expression to normal levels.

[UV phototherapy : UV phototherapy and photodiagnostics-a practical overview]

UV phototherapy is an essential and efficient therapeutic option in the treatment of dermatological diseases. It is an integral part of multiple guidelines and maintains its high clinical significance despite the development of new therapeutic options for systemic treatment. Due to the difficult revenue situation, the market for ready-to-use products of psoralen and UV therapy devices is constantly changing.

Utilizing UVA-1 Phototherapy

There is a long history of utilization of phototherapy for treatment of skin conditions. Because of its longer wavelength, UVA1 phototherapy is able to penetrate into the dermis and subcutis. This depth of penetration, combined with its unique immunomodulating properties, makes UVA1 an effective treatment modality for many immune-mediated skin diseases. In some cases, it performs better than other types of phototherapy.

Current Insights Into The Management Of Discoid Lupus Erythematosus

Discoid lupus erythematosus is the most disfiguring and common presentation of chronic cutaneous lupus erythematosus. Although most patients will respond to lifestyle measures and topical treatment, a non-negligible number of patients will require systemic and physical therapy, either alone or in combination. We performed a review of the available evidence on the discoid lupus erythematosus treatment. Lifestyle measures and topical treatment (corticosteroids and topical calcineurin inhibitors) remain the therapeutic strategies with the highest evidence level. Within systemic treatment approaches, antimalarial drugs are still the first-line therapy, while other systemic and physical therapies have highly variable evidence. Hence, we propose a therapeutic algorithm based on the strength of recommendations of the different treatment modalities, focusing on the refractory disease.

Lupus erythematosus tumidus: clinical perspectives

Lupus erythematosus tumidus (LET) is an uncommon and photosensitive inflammatory skin disorder which is characterised by erythematous urticarial plaques. In the last 20 years, extensive research on clinical and histological aspects of the disease have led to a better characterization of this nosological entity and to differentiate it from other similar or related diseases. Today, LET is considered as a separate subtype of cutaneous lupus erythematosus (CLE) with a benign, intermittent clinical course (intermittent CLE, ICLE) and only rarely associated with systemic lupus erythematosus (SLE).

A review of cutaneous lupus erythematosus: improving outcomes with a multidisciplinary approach

Cutaneous lupus erythematosus encompasses a spectrum of cutaneous disease with different phenotypes, and it potentially intersects with many disciplines in medicine. This review examines the epidemiology, clinical subtypes, pathology, psychology and intervention options for this disorder. It is important to understand the psychological distress that cutaneous lupus can cause and if needed actively investigate this possibility with the patient. Careful liaison between disciplines will achieve the optimum outcome.

Photosensitivity and photoprotection in patients with lupus erythematosus

Lupus erythematosus (LE) represents a spectrum of inflammatory autoimmune disease comprising varying clinical entities ranging from primary cutaneous to systemic disease. There is a clear relationship between ultraviolet irradiation (UVR) and the clinical manifestations of LE in both adult and pediatric populations. Although it has been established that UVR exacerbates pre-existing LE, it remains unclear whether UVR induces the development of the disease. This review serves to discuss effective photoprotective measures in LE and describe the pathogenic relationship of UVR and LE.

Standardized Ultraviolet-A Exposure Provokes Skin Reaction in Systemic Lupus Erythematosus

The immediate, 1 day and 14 days skin reaction was determined in 23 female SLE patients and 23 age-matched controls after standardized exposure to ultraviolet light of the UV-A wavelengths (320-440 nm). Eighteen of the patients and 12 of the controls were photosensitive by history. Eight separate sites on the buttocks were exposed to UV-A light, four sites at doses between 42 and 252 kJ/m2 and four sites with longpass filters (320, 345, 360 and 375 nm). The reactions on test sites were graded by two independent observers unaware of given doses or filter location. All patients and controls reacted with immediate erythema irrespectively of the presence or absence of photosensitivity. After 1 day, 39% of controls and 78% of patients had erythema and the reactions were more pronounced to longwave UV-A light (>320 nm) in the patients (P < 0.001). After 14 days, six patients, but no control, had persistent erythema (P = 0.04). Interestingly, three of the four patients without anamnestic photosensitivity did not react on days 1 or 14, while the pattern seen in the controls on day 1 was totally unpredictable with regard to reported photosensitivity. These findings strongly suggest that a considerable proportion of SLE patients show pathological skin reactions to physiological doses of longwave UV-A and not only the far more studied shortwave UV-B (290-320 nm). The responsible chromatophore for the UV-A reaction is not known.

Cellulose Nanocrystal-ZnO Nanohybrids for Controlling Photocatalytic Activity and UV Protection in Cosmetic Formulation

A high-performance semiconductor zinc oxide (ZnO) on melamine formaldehyde-coated cellulose nanocrystals (MFCNCs) was synthesized and evaluated for its application in smart cosmetics. These ZnO@MFCNC hybrid nanostructures were evaluated for their in vitro sun protection factor performance and photocatalytic activity under simulated UV and solar radiation. The photodegradation kinetics of a model pigment (methylene blue) was fitted to the Langmuir-Hinshelwood model. A 4-fold increase in the photocatalytic activity of ZnO@MFCNCs was observed when compared to pure ZnO. This is associated with (i) increased specific surface area provided by the MFCNC template, (ii) confined surface energy and controlled growth of ZnO nanoparticles, and (iii) entrapment of photoinduced charge carriers in the pores of the core-shell MFCNC rod, followed by fast promotion of interfacial e-charge transfer to the surface of the catalyst. The present study demonstrates how an increase in photocatalytic activity can be engineered without the introduction of structural defects or band gap tailoring of the semiconductor. The aqueous-based ZnO@MFCNC hybrid system displayed attractive UV-absorption and photocatalytic characteristics, offering the conversion of this renewable and sustainable technology into intelligent cosmetic formulations.

Autoantibodies Recognizing Secondary NEcrotic Cells Promote Neutrophilic Phagocytosis and Identify Patients With Systemic Lupus Erythematosus

Deficient clearance of apoptotic cells reportedly contributes to the etiopathogenesis of the autoimmune disease systemic lupus erythematosus (SLE). Based on this knowledge, we developed a highly specific and sensitive test for the detection of SLE autoantibodies (AAb) utilizing secondary NEcrotic cell (SNEC)-derived material as a substrate. The goal of the present study was to validate the use of SNEC as an appropriate antigen for the diagnosis of SLE in large cohort of patients. We confirmed the presence of apoptotically modified autoantigens on SNEC (dsDNA, high mobility group box 1 protein, apoptosis-associated chromatin modifications, e.g., histones H3-K27-me3; H2A/H4 AcK8,12,16; and H2B-AcK12). Anti-SNEC AAb were measured in the serum of 155 patients with SLE, 89 normal healthy donors (NHD), and 169 patients with other autoimmune connective tissue diseases employing SNEC-based indirect enzyme-linked immunosorbent assay (SNEC ELISA). We compared the test performance of SNEC ELISA with the routine diagnostic tests dsDNA Farr radioimmunoassay (RIA) and nucleosome-based ELISA (anti-dsDNA-NcX-ELISA). SNEC ELISA distinguished patients with SLE with a specificity of 98.9% and a sensitivity of 70.6% from NHD clearly surpassing RIA and anti-dsDNA-NcX-ELISA. In contrast to the other tests, SNEC ELISA significantly discriminated patients with SLE from patients with rheumatoid arthritis, primary anti-phospholipid syndrome, spondyloarthropathy, psoriatic arthritis, and systemic sclerosis. A positive test result in SNEC ELISA significantly correlated with serological variables and reflected the uptake of opsonized SNEC by neutrophils. This stresses the relevance of SNECs in the pathogenesis of SLE. We conclude that SNEC ELISA allows for the sensitive detection of pathologically relevant AAb, enabling its diagnostic usage. A positive SNEC test reflects the opsonization of cell remnants by AAb, the neutrophil recruitment to tissues, and the enhancement of local and systemic inflammatory responses.

Oxidative stress and dietary micronutrient deficiencies contribute to overexpression of epigenetically regulated genes by lupus T cells

Patients with active lupus have altered T cells characterized by low DNA methyltransferase levels. We hypothesized that low DNA methyltransferase levels synergize with low methionine levels to cause greater overexpression of genes normally suppressed by DNA methylation. CD4+ T cells from lupus patients and controls were stimulated with PHA then cultured in custom media with normal or low methionine levels. Oxidative stress was induced by treating the normal CD4+ T cells with peroxynitrite prior to culture. Methylation sensitive gene expression was measured by flow cytometry. Results showed low methionine levels caused greater overexpression of methylation sensitive genes in peroxynitrite treated T cells relative to untreated T cells, and in T cells from lupus patients relative to T cells from healthy controls. In conclusion, low dietary transmethylation micronutrient levels and low DNA methyltransferase levels caused either by oxidative stress or lupus, have additive effects on methylation sensitive T cell gene expression.

Cutaneous lupus erythematosus: Reflecting on practice-changing observations over the past 50 years

Several historical observations have led to the current understanding of the diagnosis, evaluation, and management of patients with cutaneous lupus erythematosus. Seminal advances in the management of this disease include the development of a classification system for cutaneous lupus, the use of a validated scoring system to assess patient disease activity, and expansion of knowledge of the action spectrum of this disease; further, observations regarding certain medications as potential causes of subacute cutaneous lupus erythematosus, the risk of progression from "pure" cutaneous disease to systemic disease, and traditional versus newer therapies are reviewed with closer inspection.

Ultraviolet B Irradiation Causes Stimulator of Interferon Genes-Dependent Production of Protective Type I Interferon in Mouse Skin by Recruited Inflammatory Monocytes

OBJECTIVE

Photosensitivity is common in patients with systemic lupus erythematosus, although the mechanisms linking ultraviolet (UV) light to flares are not well understood. We undertook this study to determine whether repetitive UVB exposure could induce type I interferon (IFN) production in normal mouse skin, and to investigate the roles of inflammatory monocytes and plasmacytoid dendritic cells (PDCs) in type I IFN production and development of UVB irradiation-induced inflammation.

METHODS

Mice were irradiated with UVB at 100 mJ/cm² for 5 days, and cutaneous manifestations were examined by messenger RNA expression of inflammatory and type I IFN response genes, histology, and flow cytometry. Inflammatory monocyte and PDC depletion experiments were performed in CCR2-diphtheria toxin receptor (DTR)-transgenic mice and blood dendritic cell antigen 2-DTR-transgenic mice. The roles of type I IFN and of the adaptor protein stimulator of IFN genes (STING) in UVB irradiation-induced inflammation were investigated using IFN-α/β/ω receptor (IFNAR)-knockout mice and STING-knockout mice.

RESULTS

Repeated UVB irradiation stimulated an inflammatory cell infiltrate and induction of type I IFN and proinflammatory cytokines. Interestingly, the type I IFN response was independent of PDCs but dependent on inflammatory monocytes, which were recruited following UVB irradiation. The adaptor protein STING was necessary for both type I IFN and proinflammatory cytokine expression in the skin. UVB-irradiated IFNAR-knockout mice showed increased levels of proinflammatory genes and more severe inflammation by histology, suggesting a protective role for type I IFN.

CONCLUSION

In wild-type mice, repeated doses of UVB irradiation induce monocyte-dependent and PDC-independent expression of type I IFN together with expression of other proinflammatory cytokines. Induction is dependent on the adaptor protein STING. Surprisingly, studies using IFNAR-deficient mice revealed that type I IFN protects against UVB irradiation-induced skin inflammation, in part by attenuating proinflammatory cytokine expression and limiting tissue damage.

Trigger factors of cutaneous lupus erythematosus: a review of current literature

It is currently believed that autoimmune conditions are triggered and aggravated by a variety of environmental factors such as cigarette smoking, infections, ultraviolet light or chemicals, as well as certain medications and vaccines in genetically susceptible individuals. Recent scientific data have suggested a relevant role of these factors not only in systemic lupus erythematosus, but also in cutaneous lupus erythematosus (CLE). A variety of environmental factors have been proposed as initiators and exacerbators of this disease. In this review we focused on those with the most convincing evidence, emphasizing the role of drugs in CLE. Using a combined search strategy of the MEDLINE and CINAHL databases the following trigger factors and/or exacerbators of CLE have been identified and described: drugs, smoking, neoplasms, ultraviolet radiation and radiotherapy. In order to give a practical insight we emphasized the role of drugs from various groups and classes in CLE. We also aimed to present a short clinical profile of patients with lesions induced by various drug classes.

Ultraviolet a Radiation and The Need for Protection

Erythema is a readily visible, often painful, natural phenomenon indicative of prolonged cutaneous exposure to ultraviolet (UV) radiation in the UVB range. As a result, early sunscreens were designed to provide adequate protection from UVB radiation. However, the continuous rise in the melanoma incidence rate alludes to the existence of an established photocarcinogen from which we are not well protected. Recently, scientists have been evaluating the photodamaging effects caused by wavelengths other than UVB. They have presented evidence that suggests that UVA exposure poses a greater hazard than previously acknowledged. For this reason, more emphasis must be placed on the development of broad-spectrum sunscreens providing adequate UVA and UVB protection. Additionally, regular sunscreen application must be advocated, proactive sun-protective practices must be implemented, and greater public awareness of the harmful effects of UVA and UVB radiation must be improved on, with the hope of decreasing the rate of cutaneous malignant melanoma.

[Clinical practice guidelines for systemic lupus erythematosus: Recommendations for general clinical management]

Systemic lupus erythematosus (SLE) is a complex rheumatic multisystemic disease of autoimmune origin with significant potential morbidity and mortality. It is one of the most common autoimmune diseases with an estimated prevalence of 20-150 cases per 100,000 inhabitants. The clinical spectrum of SLE is wide and variable both in clinical manifestations and severity. This prompted the Spanish Ministry of Health, Social Services and Equality to promote and fund the development of a clinical practice guideline (CPG) for the clinical care of SLE patients within the Programme of CPG in the National Health System which coordinates GuiaSalud. This CPG is is intended as the reference tool in the Spanish National Health System in order to support the comprehensive clinical management of people with SLE by all health professionals involved, regardless of specialty and level of care, helping to standardize and improve the quality of clinical decisions in our context in order to improve the health outcomes of the people affected. The purpose of this document is to present and discuss the rationale of the recommendations on the general management of SLE, specifically, clinical follow-up, general therapeutic approach, healthy lifestyles, photoprotection, and training programmes for patients. These recommendations are based on the best available scientific evidence, on discussion and the consensus of expert groups.

Kutaner Lupus erythematodes

The diagnosis of cutaneous lupus erythematosus (CLE) requires a specific diagnostic approach to identify subtypes, to address differential diagnostic considerations, and to rule out systemic organ involvement. In addition to a detailed patient's history and clinical evaluation of the skin, histopathologic and immunofluorescent examination of a skin biopsy as well as laboratory screening are recommended. Photoprovocation tests can be performed to confirm the diagnosis of CLE and to assess photosensitivity in these patients. Recently, a scoring system for the activity of the cutaneous manifestations in CLE has been developed and validated which involves anatomical areas and morphologic signs of the skin lesions. In all subtypes of CLE, antimalarials are still the treatment of choice. Advances in biotechnology have led to the development of several novel agents for the treatment of autoimmune diseases; however, controlled trials have not been performed in patients with CLE. Furthermore, there is need for specific immunointervention, especially for patients who fail to respond to standard therapies. The second part of this review will enable the reader to differentiate CLE from other diseases and to suggest specific diagnostic procedures and treatment approaches.

Lupus erythematosus revisited

Lupus erythematosus (LE) is a multifactorial autoimmune disease with clinical manifestations of differing severity. The exact pathomechanisms and interactions resulting in the inflammatory and immunological processes of this heterogeneous disease remain elusive. Approaches in the understanding of the pathomechanisms revealed that the clinical expression of LE is predisposed by susceptibility genes and that various environmental factors are responsible for an abnormal immune response. Several studies demonstrated that ultraviolet (UV) light is one of the major factors in the pathogenesis of the disease. Standardized photoprovocation in patients with LE has been shown to be a safe and efficient model for evaluating the underlying pathomechanisms which lead to the production of autoantibodies and immune complexes. In particular, interferons were defined as important players in the early activation of the immune system and were observed to play a specific role in the immunological interface between the innate and the adaptive immune system. Abnormalities or disturbances in the different processes of cell death, such as apoptosis or necrosis, have also been recognized as crucial in the pathogenesis of LE. Although each process is different and characterized by unique features, the processes are interrelated and result in a complex disease.

Epigenetics changes associated to environmental triggers in autoimmunity

Autoimmune diseases (AIDs) are chronic conditions initiated by the loss of immunological tolerance to self-antigens and represent a heterogeneous group of disorders that affect specific target organs or multiple organs in different systems. While the pathogenesis of AID remains unclear, its aetiology is multifunctional and includes a combination of genetic, epigenetic, immunological and environmental factors. In AIDs, several epigenetic mechanisms are defective including DNA demethylation, abnormal chromatin positioning associated with autoantibody production and abnormalities in the expression of RNA interference (RNAi). It is known that environmental factors may interfere with DNA methylation and histone modifications, however, little is known about epigenetic changes derived of regulation of RNAi. An approach to the known environmental factors and the mechanisms that alter the epigenetic regulation in AIDs (with emphasis in systemic lupus erythematosus, the prototype of systemic AID) are showed in this review.

Photosensitivity, apoptosis, and cytokines in the pathogenesis of lupus erythematosus: a critical review

The underlying pathomechanisms of lupus erythematosus (LE), a multifactorial autoimmune disease, remain elusive. Due to the clinical evidence demonstrating a clear relationship between ultraviolet (UV) light exposure and skin lesions of LE, photosensitivity has been proven to be an important factor in the pathogenesis of the disease. Standardised photoprovocation with UVA and UVB irradiation has been shown to be a reliable model for evaluating photosensitivity in patients with cutaneous LE (CLE) and analysing the underlying medical conditions of the disease. In this respect, UV irradiation can cause aberrant induction of apoptosis in keratinocytes and contribute to the appearance of excessive apoptotic cells in the skin of CLE patients. Moreover, apoptotic cells that cannot be cleared by phagocytes may undergo secondary necrosis and release proinflammatory compounds and potential autoantigens, which may contribute to the inflammatory micromilieu that leads to formation of skin lesions in the disease. In addition to UV-mediated induction of apoptosis, the molecular and cellular factors that may cause the abnormal long-lasting photoreactivity in CLE include mediators of inflammation, such as cytokines and chemokines. In particular, interferons (IFNs) are important players in the early activation of the immune system and have a specific role in the immunological interface between the innate and the adaptive immune system. The fact that treatment with recombinant type I IFNs (α and β) can induce not only systemic organ manifestations but also LE-like skin lesions provides additional evidence for a pathogenetic role of these IFNs in the disease.

Photoaggravated disorders

Photoaggravated skin disorders are diseases that occur without UV radiation but are sometimes or frequently exacerbated by UV radiation. In conditions, such as lupus erythematosus, photoaggravation occurs in a majority of patients, whereas in conditions, such as psoriasis and atopic dermatitis, only a subset of patients demonstrate photoaggravation. Polymorphous light eruption is a common photodermatosis in all skin types, making it important to differentiate photoaggravation of an underlying disorder, such as lupus erythematosus, from superimposed polymorphous light eruption. Disease-specific treatments should be instituted where possible. A key component of management of photoaggravated conditions is photoprotection with behavioral change, UV-protective clothing, and broad-spectrum sunscreen.

Environmental exposures, epigenetic changes and the risk of lupus

A dose-dependent combination of environmental exposures, estrogenic hormones and genetic predisposition is thought to be required for lupus to develop and flare, but how the environment modifies the immune system in genetically predisposed people is unclear. Current evidence indicates that environmental agents that inhibit DNA methylation can convert normal antigen-specific CD4+ T lymphocytes into autoreactive, cytotoxic, pro-inflammatory cells that are sufficient to cause lupus-like autoimmunity in animal models, and that the same changes in DNA methylation characterize CD4+ T cells from patients with active lupus. Environmental agents implicated in inhibiting T-cell DNA methylation include the lupus-inducing drugs procainamide and hydralazine, as well as diet, and agents causing oxidative stress, such as smoking, UV light exposure, and infections, which have been associated with lupus onset or disease activity. Other studies demonstrate that demethylated T cells cause only anti-DNA antibodies in mice lacking a genetic predisposition to lupus, but are sufficient to cause lupus-like autoimmunity in genetically predisposed mice and likely people, and that estrogens augment the disease. Collectively, these studies suggest that environmental agents that inhibit DNA methylation, together with lupus genes and estrogens or endocrine disruptors, combine in a dose-dependent fashion to cause lupus flares.

The national incidence and clinical picture of SLE in children in Australia – a report from the Australian Paediatric Surveillance Unit

Objectives

The objectives of this paper are to prospectively determine the incidence of paediatric systemic lupus erythematosus (pSLE) in Australia as well as describe the demographics, clinical presentation and one-year outcome.

Study design

Newly diagnosed cases of pSLE were ascertained prospectively from October 2009 to October 2011 through the Australian Paediatric Surveillance Unit (a national monthly surveillance scheme for notification of childhood rare diseases) as well as national subspecialty groups. Questionnaires were sent to notifying physicians at presentation and at one year.

Results

The annual incidence rate was 0.32 per 105 children aged less than 16 years. The incidence was significantly higher in children of Asian or Australian Aboriginal and Torres Strait Islander parents. Approximately one-third of children underwent a renal biopsy at presentation and 7% required dialysis initially although only one child had end-stage kidney disease (ESKD) at one-year follow-up.

Conclusion

The incidence of pSLE in Australia is comparable to that worldwide with a significantly higher incidence seen in children of Asian and Australian Aboriginal and Torres Strait Islander backgrounds. Renal involvement is common but progression to ESKD, at least in the short term, is rare.

A case of subacute cutaneous lupus erythematosus as a result of ranibizumab (Lucentis) treatment

Cutaneous lupus erythematosus is a previously undiagnosed side-effect of ranibizumab. Here, we present a case of an 82-year-old female Caucasian patient with wet age-related macular degeneration. Following a single intraocular injection of Lucentis (ranibizumab), she developed a subacute cutaneous lupus erythematosus which, with treatment, took nearly 12 months to resolve. This shows that cutaneous lupus erythematosus is a potential side-effect of many medications, including ranibizumab, as in our case and, in an aging population where polypharmacy is a growing reality, clinicians should be aware of how to diagnose and best manage such cases.

Systemic lupus erythematosus: epidemiology, pathophysiology, manifestations, and management

Systemic lupus erythematosus is a chronic autoimmune disorder characterized by production of autoantibodies directed against nuclear and cytoplasmic antigens, affecting several organs. Although cause is largely unknown, pathophysiology is attributed to several factors. Clinically, this disorder is characterized by periods of remission and relapse and may present with various constitutional and organ-specific symptoms. Diagnosis is achieved via clinical findings and laboratory examinations. Therapies are based on disease activity and severity. General treatment considerations include sun protection, diet and nutrition, smoking cessation, exercise, and appropriate immunization, whereas organ-specific treatments include use of steroidal and nonsteroidal anti-inflammatory drugs, immunosuppressive agents, and biologic agents.

Photoimmunology

The discipline that investigates the biologic effects of ultraviolet radiation on the immune system is called photoimmunology. Photoimmunology evolved from an interest in understanding the role of the immune system in skin cancer development and why immunosuppressed organ transplant recipients are at a greatly increased risk for cutaneous neoplasms. In addition to contributing to an understanding of the pathogenesis of nonmelanoma skin cancer, the knowledge acquired about the immunologic effects of ultraviolet radiation exposure has provided an understanding of its role in the pathogenesis of other photodermatologic diseases.

Lupus erythematosus: considerations about clinical, cutaneous and therapeutic aspects

Systemic Lupus Erythematosus is a chronic inflammatory disease with multifactorial etiology. Although clinical manifestations are varied, the skin is an important target-organ, which contributes to the inclusion of skin lesions in 4 out of the 17 new criteria for the diagnosis of the disease, according to the Systemic Lupus International Collaborating Clinics. The cutaneous manifestations of lupus are pleomorphic. Depending on their clinical characteristics, they can be classified into Acute Cutaneous Lupus Erythematosus, Subacute Cutaneous Lupus Erythematosus, Chronic Cutaneous Lupus Erythematosus and Intermittent Cutaneous Lupus Erythematosus. Treatment is based on preventive measures, reversal of inflammation, prevention of damage to target organs and relief of adverse events due to pharmacological therapy. The most commonly used treatment options are topical, systemic and surgical treatment, as well as phototherapy. The correct handling of the cases depends on a careful evaluation of the morphology of the lesions and the patient's general status, always taking into consideration not only the benefits but also the side effects of each therapeutic proposal.

Updated analysis of standardized photoprovocation in patients with cutaneous lupus erythematosus

OBJECTIVE

To determine the frequency and reproducibility of standardized photoprovocation in patients with cutaneous lupus erythematosus (CLE) and report our long-term experience.

METHODS

Photoprovocation using a standardized protocol was evaluated retrospectively in 566 patients. A diagnosis of CLE was clinically and/or histologically confirmed in 431 patients, and 315 patients with polymorphic light eruption (PLE) were additionally included as controls. Data were statistically analyzed using an SPSS database.

RESULTS

A total of 61.7% of the 431 CLE patients exhibited a positive photoprovocation, with a significantly longer latency period for the development of skin lesions after ultraviolet (UV) A and/or UVB irradiation than PLE patients (P < 0.001). The frequency of positive photoprovocation varied among the CLE subtypes, and intermittent CLE was the most photosensitive disease entity (74.8%). Subsequent photoprovocation in 35 patients demonstrated that CLE patients with an initial positive result exhibited a significantly higher frequency of a positive photoprovocation at a later time point (P = 0.013). However, an initial positive photoprovocation did not definitively predict a positive reaction at a later time point. Moreover, patient history of photosensitivity was not a predictor for the photoprovocation outcome.

CONCLUSION

Standardized photoprovocation is a useful tool to reproducibly induce skin lesions and objectively evaluate photosensitivity in patients with CLE. These data further suggest that the reaction to UV light may change during the course of this heterogeneous disease and that photosensitivity should not be excluded in patients with a negative history of photosensitivity.

Effects of ultraviolet B exposure on DNA methylation in patients with systemic lupus erythematosus

The aim of this study was to investigate the effects of ultraviolet B (UVB) exposure on DNA methylation in patients with systemic lupus erythematosus (SLE) and its significance in the pathogenesis of SLE. T cells from 35 SLE patients and 21 healthy individuals were cultured and irradiated with UVB. The global DNA methylation profiles of the T cells obtained from the patients and controls following irradiation with UVB were assessed using specific monoclonal antibodies for 5-methylcytosine and analyzed quantitatively through flow cytometry. Real-time reverse transcription-polymerase chain reaction (RT-PCR) was used to analyze the levels of DNA methyltransferase 1 (DNMT1) and methyl CpG binding domain protein 2 (MBD2) in T cells from the patients and controls following UVB irradiation. Significant global DNA hypomethylation was observed in the SLE patients compared with the controls (P<0.01). The SLE patients also had significantly lower levels of DNMT1 mRNA expression (P<0.01) and significantly higher levels of MBD2 mRNA compared with the controls (P<0.01). DNA methylation was decreased following UVB irradiation at two different dosages and the DNA methylation levels of the patients with active SLE were more sensitive to UVB. The level of DNMT1 mRNA was decreased following UVB irradiation at the higher dosage in the patients with active SLE, but no significant difference was observed in MBD2 mRNA expression. UVB exposure is able to inhibit DNA methylation and DNMT1 mRNA expression, which is subsequently involved in the epigenetic mechanism of SLE. The process by which DNA hypomethylation occurs in patients with SLE is complicated and the multiple factors that are involved in DNA methylation and demethylation events require further study.

Photosensitivity in cutaneous lupus erythematosus

BACKGROUND

Ultraviolet radiation (UVR) is a well-known exacerbating factor for cutaneous lupus erythematosus (CLE), with photosensitivity comprising one of the American College of Rheumatology (ACR) diagnostic criteria for systemic lupus erythematosus (SLE). However, discerning true photosensitivity in this population is difficult due to the broad language utilized by the ACR and the delayed-onset nature of photosensitive lupus lesions.

AIMS

The objective of this report is to provide a review of photosensitivity, photoprovocation, and phototherapy in the context of CLE patients.

METHODS

A literature review in PubMed was conducted using the terms 'ultraviolet light,' 'lupus erythematosus,' 'photoprovocation,' or 'photosensitivity.'

RESULTS

Self-patient reporting of photosensitivity and the broad definition of photosensitivity have led to the wide range of photosensitivity rates in CLE patients. Photoprovocation testing provides a more objective method to measure photosensitivity, but even these trials demonstrate significant differences due to protocol variations. Despite UVR's deleterious effect on lupus patients, ultraviolet A (UVA)-1 may have therapeutic benefits as shown by observations on murine models and human lupus subjects.

CONCLUSIONS

Accurately discerning photosensitivity has diagnostic implications for SLE and provides motivation for greater patient adherence to photoprotective methods.

Photoprotective habits of patients with cutaneous lupus erythematosus

BACKGROUND

Previous studies have suggested that patients with cutaneous lupus erythematosus (CLE) are deficient in sunscreen use. Use of other photoprotective methods by patients with CLE has not been assessed to our knowledge.

OBJECTIVE

We sought to identify demographic and clinical characteristics of patients with CLE who have the lowest overall sun-protection habits scores, and who are least likely to practice 5 individual photoprotective methods (ie, shade, sunscreen, long sleeves, hat, and sunglasses).

METHODS

A total of 105 patients with CLE at the University of Texas Southwestern Medical Center in Dallas completed a survey to evaluate their photoprotective practices. Additional information including demographics and clinical indicators related to CLE was collected from the patients.

RESULTS

Patients with medium and dark skin (ie, Fitzpatrick skin types III-VI) and patients aged 31 to 50 years were the least likely CLE subgroups to practice overall photoprotection, as indicated by low sun-protection habits scores (P = .001 and P = .04, respectively). In terms of individual photoprotective methods, male patients with CLE were deficient in sunscreen use, but were more likely to wear hats than female patients with CLE. Sunscreen and sunglasses use was also significantly more infrequent in dark-skinned patients than those with Fitzpatrick skin types I to IV. Patients with CLE between the ages of 41 and 50 years were least likely to wear hats.

LIMITATIONS

This study was subject to reporter bias and did not cover barriers to and knowledge of photoprotection.

CONCLUSION

Cultural customs and misconceptions shared by those from the general population have a significant influence on the photoprotective habits of this CLE population. These need to be addressed to improve photoprotection rates in these at-risk individuals.

Photosensitivity disorders in children: part II

Photosensitivity disorders in children encompass a diverse group of diseases. Some inherited disorders manifest with photosensitivity early in life. Specific extracutaneous association may be the clue to diagnosis in this group of pediatric photodermatoses. Part II of this 2-part review covers hereditary photodermatoses caused by defects in nucleotide excision repair, double strand break repair, or localized or systemic biochemical abnormalities. Diagnosis and management of photoaggravated dermatoses are also discussed. Sun protection strategies are required in all patients with evidence of photosensitivity. Early recognition and prompt diagnosis is essential to minimize the long-term complications associated with inadequate photoprotection.

Cutaneous lupus erythematosus: first multicenter database analysis of 1002 patients from the European Society of Cutaneous Lupus Erythematosus (EUSCLE)

In this prospective, cross-sectional, multicenter study, we assessed clinical and laboratory characteristics from patients with cutaneous lupus erythematosus (CLE) using the Core Set Questionnaire of the European Society of Cutaneous Lupus Erythematosus (EUSCLE). 1002 (768 females, 234 males) patients with different subtypes of CLE, such as acute CLE (ACLE, 304 patients), subacute CLE (SCLE, 236 patients), chronic CLE (CCLE, 397 patients), and intermittent CLE (ICLE, 65 patients), from 13 European countries were collected and statistically analyzed by an SPSS database. The main outcome measures included gender, age at onset of disease, LE-specific and LE-nonspecific skin lesions, photosensitivity, laboratory features, and the criteria of the American College of Rheumatology (ACR) for the classification of systemic lupus erythematosus. The mean age at onset of disease was 43.0±15.7 years and differed significantly between the CLE subtypes. In 347 (34.6%) of the 1002 patients, two or more CLE subtypes were diagnosed during the course of the disease and 453 (45.2%) presented with LE-nonspecific manifestations. Drug-induced CLE and Sjögren's Syndrome had the highest prevalence in SCLE patients (13.1% and 14.0%, respectively). Photosensitivity was significantly more frequent in patients with ACLE, SCLE, and ICLE compared with those with CCLE. The detection of antinuclear antibodies such as anti-Ro/SSA and anti-La/SSB antibodies revealed further significant differences between the CLE subtypes. In summary, the EUSCLE Core Set Questionnaire and its database facilitate the analysis of clinical and laboratory features in a high number of patients with CLE and will contribute to standardized assessment and monitoring of the disease in Europe.

The consequences of UV-induced immunosuppression for human health

Exposure to UV radiation can cause suppression of specific immune responses. The pathways leading to the down-regulation are complex, starting from the absorption of UV photons by chromophores in the skin and ending with local and systemic changes in immune mediators, the generation of T and B regulatory cells and inhibition of effector and memory T cell activation. The consequences for human health are thought to be both beneficial and adverse. The former are illustrated by protection against polymorphic light eruption, and possible protection against T cell-mediated autoimmune diseases and asthma. The latter are illustrated by skin cancer, cutaneous lupus erythematosus and infectious diseases including vaccination. Many outstanding questions remain in this rapidly developing and controversial area, not least what advice to give the general public regarding their sun exposure. While considerable advances have been made in the development of strategies that preserve the health benefits of sunlight exposure and decrease its detrimental effects, further research is required before optimal levels of protection are achieved.