Pathophysiology of Cutaneous Lupus Erythematosus

IL-33/ST2 Activation Is involved in Ro60-Regulated Photosensitivity in Cutaneous Lupus Erythematosus

Interleukin- (IL-) 33 contributes to various inflammatory processes. IL-33/ST2 activation participates in systemic lupus erythematous via binding to the receptor of Suppression of Tumorigenicity 2 protein (ST2). However, whether IL-33/ST2 interferes with the nosogenesis of cutaneous lupus erythematosus (CLE) has not been reported so far. Herein, we proposed to disclose the impacts on IL-33/ST2 activation and Ro60 on CLE and their potential implications in the photosensitization of CLE cells. IL-33, ST2, and Ro60 in CLE patients' skin lesions were detected. Murine keratinocytes stimulated with or without IL-33 were irradiated by ultraviolet B (UVB), and the levels of Ro60 and inflammation markers were determined. Keratinocytes were cocultured with J774.2 macrophages and stimulated with IL-33 for analysis of chemostasis. The results identified that IL-33, ST2, and downstream inflammation markers were significantly upregulated in CLE lesions with Ro60 overexpression. Additionally, IL-33 treatment promoted the upregulation of Ro60 induced by UVB treatment in murine keratinocytes. Moreover, IL-33 stimulates keratinocytes to induce macrophage migration via enhancing the generation of the chemokine (C–C motif) ligands 17 and 22. Meanwhile, the silencing of ST2 or nuclear factor-kappa B (NF-κB) suppression abolished IL-33-induced upregulation of Ro60 in keratinocytes. Similarly, the inhibition of SOX17 expression was followed by downregulation of Ro60 in keratinocytes following IL-33 stimulation. In addition, UVB irradiation upregulated SOX17 in keratinocytes. Conclusively, the IL-33/ST2 axis interferes with Ro60-regulated photosensitization via activating the NF-κB- and PI3K/Akt- and SOX17-related pathways.

Subacute Cutaneous Lupus Erythematosus-Like Eruption Induced by Durvalumab: A Case Report and Literature Review

Reports of immune-related adverse events caused by programmed cell death-ligand 1 (PD-L1) inhibitor have been emerging. Herein, we report a subacute cutaneous lupus erythematosus (SCLE)-like eruption presented after the treatment of durvalumab in a patient with extensive-stage small cell lung carcinoma. A 74-year-old Thai man was referred to our department after experiencing multiple dusky red to brownish papules and patches with scale and erosions on photo-distributed areas after receiving 3 infusion cycles of durvalumab. Histological finding revealed epidermal atrophy with interface changes and superficial perivascular infiltration of lymphocytes. Serum antinuclear antibodies (ANA) was 1:320 and anti-Ro/Sjogren's-syndrome-related antigen A (anti-Ro/SSA) antibodies were positive (2+). Based on the history and clinicopathological correlation, the diagnosis of SCLE-like eruption due to durvalumab was made. To the best of our knowledge, this is the first case of durvalumab-induced SCLE.

Male systemic lupus erythematosus: Two distinct presentations

Systemic lupus erythematosus (SLE) multisystem autoimmune disease is characterised by a series of exacerbations and remissions. Tissues of multiple-organ systems are affected by autoantibodies. We report here two cases of SLE in male patients. Being rarer in males, diagnosis is often delayed and associated with poorer outcomes. An alert primary care physician can be instrumental in early diagnosis and ensuring better outcomes.

Recognition and Management of Cutaneous Connective Tissue Diseases

Connective tissue diseases (CTDs) encompass a broad spectrum of clinical presentations that involve multidisciplinary management. Cutaneous findings are common in CTD and careful examination of these features aids in appropriate diagnosis and subsequent evaluation. Thorough work-up of CTD is crucial to properly identify disease subtypes and systemic involvement. Management plans can be developed based on diagnosis and systemic manifestations of disease. Disease management often requires treatment with pharmacotherapies with potential for toxicities, further underscoring the importance of diagnostic accuracy in this patient population. Evolving research strives to better elucidate the pathogenic mechanisms of CTDs allowing for more targeted treatment modalities.

British Association of Dermatologists guidelines for the management of people with cutaneous lupus erythematosus (CLE) 2021

The overall objective of the guideline is to provide up-to-date, evidence-based recommendations for the management of cutaneous lupus erythematosus (CLE) in the presence or absence of systemic lupus erythematosus (SLE) in adults, young people and children. The document aims to: offer an appraisal of all relevant literature up to December 2020, focusing on any key developments address important, practical clinical questions relating to the primary guideline objective. provide guideline recommendations and if appropriate research recommendations.

Long-Term Risk of Autoimmune Diseases other than Systemic Lupus Erythematosus in Cutaneous Lupus Erythematosus-Alone Patients: A 10-Year Nationwide Cohort Study

BACKGROUND

Up to 25% of patients with cutaneous lupus erythematosus (CLE) can develop systemic lupus erythematosus (SLE). However, the risk of autoimmune diseases other than SLE in CLE patients who have only skin manifestations (CLE-alone) has rarely been explored.

OBJECTIVE

To investigate the long-term risk and independent factors of non-SLE autoimmune diseases among CLE-alone patients.

METHOD

A nationwide cohort study using the Taiwanese National Health Insurance Research Database 1997-2013. CLE patients and matched subjects were included. Cumulative incidences of autoimmune diseases after 1 year of CLE-alone diagnosis were compared. Cox proportional hazard model was also performed.

RESULTS

A total of 971 CLE-alone patients and 5,175 reference subjects were identified. The 10-year cumulative incidence of autoimmune diseases other than SLE was significantly elevated in the CLE-alone cohort (9.00%, 95% confidence interval [CI] 6.72-11.29) than in the reference cohort (4.20%, 95% CI 3.53-4.87%) (p < 0.001). CLE-alone was independently associated with non-SLE autoimmune diseases (adjusted hazard ratio 1.55, 95% CI 1.10-2.18). Among CLE-alone patients, females and those taking long-term systemic corticosteroids (a proxy for extensive disease) were associated with non-SLE autoimmune diseases after adjusting for the number of repeated autoimmune laboratory tests.

CONCLUSION

CLE-alone is independently associated with future non-SLE autoimmune diseases.

The pathogenesis of cutaneous lupus erythematosus: The aberrant distribution and function of different cell types in skin lesions

Cutaneous lupus erythematosus (CLE) is an autoimmune disease with a broad range of cutaneous manifestations. In skin lesions of CLE, keratinocytes primarily undergo apoptosis. Interferon-κ(IFN-κ) is belonged to type I interferons (type I IFNs) and is selectively produced by keratinocytes. Recently, keratinocytes selectively produced IFN-κ is identified to be a key to trigger type I interferon responses in CLE. Other immune cells such as plasmacytoid dendritic cells (pDCs) are identified to be relevant origin of type I interferons (type I IFNs) which are central to the development of CLE lesions and responsible for mediating Th1 cell activity. Other types of cells such as neutrophils, B cells and Th17 cells also are involved in the development of this disease. The close interaction of those cells composes a comprehensive and complicated network in CLE. In this review, we discussed the aberrant distribution and function of different cells types involved in this disease and will offer a new direction for research and therapy in the near future.

An Update on the Pathogenesis of Cutaneous Lupus Erythematosus and Its Role in Clinical Practice

PURPOSE OF REVIEW

Understanding the pathogenesis of cutaneous lupus erythematosus (CLE) is an important step in developing new medications and providing effective treatment to patients. This review focuses on novel research within CLE pathogenesis, as well as some of the medications being developed based on this knowledge.

RECENT FINDINGS

The subtle differences between systemic lupus erythematosus (SLE) and CLE pathogenesis are highlighted by differences in the circulating immune cells found in each disease, as well as the specific pathways activated by ultraviolet light. Plasmacytoid dendritic cells and the related type I interferon pathway are major components of CLE pathogenesis, and as such, therapies targeting components of this pathway have been successful in recent clinical trials. B cell-depleting therapies have shown success in SLE; however, their role in CLE is less clear. Understanding the differences between these manifestations of lupus allows for the development of therapies that are more effective in skin-specific disease. Discovering key pathways in CLE pathogenesis is critical for understanding the clinical features of the disease and ultimately developing new and effective therapies.

Toxic Epidermal Necrolysis-like Subacute Cutaneous Lupus Erythematosus: a Case Report

Cutaneous lupus erythematosus (LE) encompasses a wide spectrum of dermatologic manifestations, including toxic epidermal necrolysis (TEN)-like presentations of acute or subacute cutaneous lupus erythematosus (TEN-like ACLE/SCLE). Although the clinical characteristics and histological features of these rare entities may closely mimic TEN, several subtle differences can help in differentiation between these conditions. We report a case of a patient with SCLE which developed drug unrelated TEN-like blisters after prolonged, intensive sun exposure and focus on a discussion of distinctive features that can be used to differentiate drug-induced TEN and TEN-like presentation of ACLE/SCLE.

Regulatory T cells in inflammatory skin disease: from mice to humans

The skin is the largest organ in the body and one of the primary barriers to the environment. In order to optimally protect the host, the skin is home to numerous immune cell subsets that interact with each other and other non-immune cells to maintain organ integrity and function. Regulatory T cells (Tregs) are one of the largest immune cell subsets in skin. They play a critical role in regulating inflammation and facilitating organ repair. In doing so, they adopt unique and specialized tissue-specific functions. In this review, we compare and contrast the role of Tregs in cutaneous immune disorders from mice and humans, with a specific focus on scleroderma, alopecia areata, atopic dermatitis, cutaneous lupus erythematosus and psoriasis.

The color of skin: black diseases of the skin, nails, and mucosa

Gradations in skin color are a consequence of differing amounts of melanin and their varying distribution. Although many darkly pigmented skin lesions are melanocytic and can be attributed to melanin content, the color of a black lesion can also be due to blood, necrotic tissue, or exogenous pigment. The source, pattern, and distribution of the color in black lesions usually offer important insight into its etiology. This contribution reviews conditions that can take on a black color, discussing the cause of the hue and any additional impact sun exposure may have.

Cutaneous lupus erythematosus: new insights into pathogenesis and therapeutic strategies

Cutaneous lupus erythematosus (CLE) is an autoimmune disease that can present as an isolated skin disease or as a manifestation within the spectrum of systemic lupus erythematosus. The clinical spectrum of CLE is broad, ranging from isolated discoid plaques to widespread skin lesions. Histologically, skin lesions present as interface dermatitis (inflammation of the skin mediated by anti-epidermal responses), which is orchestrated by type I and type III interferon-regulated cytokines and chemokines. Both innate and adaptive immune pathways are strongly activated in the formation of skin lesions owing to continuous re-activation of innate pathways via pattern recognition receptors (PRRs). These insights into the molecular pathogenesis of skin lesions in CLE have improved our understanding of the mechanisms underlying established therapies and have triggered the development of targeted treatment strategies that focus on immune cells (for example, B cells, T cells or plasmacytoid dendritic cells), as well as immune response pathways (for example, PRR signalling, Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signalling and nuclear factor-κB signalling) and their cytokines and chemokines (for example, type I interferons, CXC-chemokine ligand 10 (CXCL10), IL-6 and IL-12).

In silico Analyses of Skin and Peripheral Blood Transcriptional Data in Cutaneous Lupus Reveals CCR2-A Novel Potential Therapeutic Target

Cutaneous lesions feature prominently in lupus erythematosus (LE). Yet lupus and its cutaneous manifestations exhibit extraordinary clinical heterogeneity, making it imperative to stratify patients with varying organ involvement based on molecular criteria that may be of clinical value. We conducted several in silico bioinformatics-based analyses integrating chronic cutaneous lupus erythematosus (CCLE)-skin and blood expression profiles to provide novel insights into disease mechanisms and potential future therapy. In addition to substantiating well-known prominent apoptosis and interferon related response in both tissue environments, the overrepresentation of GO categories in the datasets, in the context of existing literature, led us to model a “disease road-map” demonstrating a coordinated orchestration of the autoimmune response in CCLE reflected in three phases: (1) initiation, (2) amplification, and (3) target damage in skin. Within this framework, we undertook in silico interactome analyses to identify significantly “over-connected” genes that are potential key functional players in the metabolic reprogramming associated with skin pathology in CCLE. Furthermore, overlapping and distinct transcriptional “hot spots” within CCLE skin and blood expression profiles mapping to specified chromosomal locations offer selected targets for identifying disease-risk genes. Lastly, we used a novel in silico approach to prioritize the receptor protein CCR2, whose expression level in CCLE tissues was validated by qPCR analysis, and suggest it as a drug target for use in future potential CCLE therapy.

Subacute cutaneous lupus erythematosus presenting in twins

Subacute cutaneous lupus erythematosus is a clinically distinct form of cutaneous lupus erythematosus, with age of onset typically in the second to fifth decades. Eleven cases have been reported in childhood, and we present the first known case of subacute cutaneous lupus erythematosus in identical twins. Although flares are typically photo-induced, we present an annular eruption typical of subacute cutaneous lupus erythematosus with concurrent pinworm infestation, with recurrence of disease with cutaneous larva migrans. The patient's identical twin had a similar eruption with pinworm infection. This case highlights the possibility of parasitic infestation as a trigger for subacute cutaneous lupus erythematosus in genetically susceptible individuals.

Fn14 deficiency protects lupus-prone mice from histological lupus erythematosus-like skin inflammation induced by ultraviolet light

The cytokine TNF-like weak inducer of apoptosis (TWEAK) and its receptor Fn14 are involved in cell survival and cytokine production. The TWEAK/Fn14 pathway plays a role in the pathogenesis of spontaneous cutaneous lesions in the MRL/lpr lupus strain; however, the role of TWEAK/Fn14 in disease induced by ultraviolet B (UVB) irradiation has not been explored. MRL/lpr Fn14 knockout (KO) was compared to MRL/lpr Fn14 wild-type (WT) mice following exposure to UVB. We found that irradiated MRL/lpr KO mice had significantly attenuated cutaneous disease when compared to their WT counterparts. There were also fewer infiltrating immune cells (CD3⁺ , IBA-1⁺ and NGAL⁺ ) in the UVB-exposed skin of MRL/lpr Fn14KO mice, as compared to Fn14WT. Furthermore, we identified several macrophage-derived proinflammatory chemokines with elevated expression in MRL/lpr mice after UV exposure. Depletion of macrophages, using a CSF-1R inhibitor, was found to be protective against the development of skin lesions after UVB exposure. In combination with the phenotype of the MRL/lpr Fn14KO mice, these findings indicate a critical role for Fn14 and recruited macrophages in UVB-triggered cutaneous lupus. Our data strongly suggest that TWEAK/Fn14 signalling is important in the pathogenesis of UVB-induced cutaneous disease manifestations in the MRL/lpr model of lupus and further support this pathway as a possible target for therapeutic intervention.

Highly selective inhibition of Bruton's tyrosine kinase attenuates skin and brain disease in murine lupus

Background

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that affects different end organs, including skin and brain. We and others have previously shown the importance of macrophages in the pathogenesis of cutaneous and neuropsychiatric lupus. Additionally, autoantibodies produced by autoreactive B cells are thought to play a role in both the skin and central nervous system pathologies associated with SLE.

Methods

We used a novel inhibitor of Bruton’s tyrosine kinase (BTK), BI-BTK-1, to target both macrophage and B cell function in the MRL-lpr/lpr murine model of SLE, and examined the effect of treatment on skin and brain disease.

Results

We found that treatment with BI-BTK-1 significantly attenuated the lupus associated cutaneous and neuropsychiatric disease phenotypes in MRL/lpr mice. Specifically, BI-BTK-1 treated mice had fewer macroscopic and microscopic skin lesions, reduced cutaneous cellular infiltration, and diminished inflammatory cytokine expression compared to control mice. BTK inhibition also significantly improved cognitive function, and decreased accumulation of T cells, B cells, and macrophages within the central nervous system, specifically the choroid plexus.

Conclusions

Directed therapies may improve the response rate in lupus-driven target organ involvement, and decrease the dangerous side effects associated with global immunosuppression. Overall, our results suggest that inhibition of BTK may be a promising therapeutic option for cutaneous and neuropsychiatric disease associated with SLE.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1500-0) contains supplementary material, which is available to authorized users.

Risk of Cerebrovascular Accidents and Ischemic Heart Disease in Cutaneous Lupus Erythematosus: A Population-Based Cohort Study

OBJECTIVE

It is unclear whether isolated cutaneous lupus erythematosus (CLE) affects cardiovascular risk. We estimated the cumulative incidence and mortality of cardiovascular diseases in a population-based CLE cohort and compared the risk with a matched non-CLE cohort.

METHODS

All incident cases of CLE in Olmsted County, Minnesota, between 1965 and 2005 were followed until December 2013. The cumulative incidence of cerebrovascular accidents (CVAs [including stroke and transient ischemic attack]), ischemic heart disease (IHD [including coronary artery disease, myocardial infarction, and angina pectoris]), heart failure, and peripheral arterial disease (PAD) was derived and compared to an age-, sex-, and calendar year-matched non-CLE cohort using Cox models.

RESULTS

There were 155 patients with CLE (mean ± SD age at diagnosis 48 ± 16 years, 65% female, mean ± SD BMI 26.3 ± 7.1 kg/m² , 40% smokers, 9% with diabetes mellitus). During a median followup of 14.6 years, 41 CLE patients had cardiovascular events (15 patients with CVAs, 32 patients with IHD), with a 20-year cumulative incidence of 31.6%. As compared to non-CLE subjects, the risk of CVAs (smoking-adjusted hazard ratio [HR] 2.97 [95% confidence interval (95% CI) 1.13-7.78]) and PAD (HR 2.06 [95% CI 0.99-4.32]) was increased in patients with CLE, but the risk of IHD was not increased (HR 0.94 [95% CI 0.57-1.54]). There was no increase in cardiovascular mortality (HR 1.68 [95% CI 0.76-3.75]). The magnitude of risk for any cardiovascular outcome was not significantly influenced by the extent of cutaneous involvement.

CONCLUSION

CLE may be associated with an increased risk of CVAs and PAD, but not IHD. Factors contributing to increased CVA risk in patients with CLE merit evaluation.

Topical drug-induced subacute cutaneous lupus erythematosus isolated to the hands

Subacute cutaneous lupus erythematosus (SCLE) is a well-defined subtype of lupus erythematosus, characterised by photosensitivity, annular and/or psoriasiform lesions, variable systemic involvement and presence of circulating SSA/anti-Ro antibodies. SCLE may be idiopathic or drug-induced. Both the idiopathic and drug-induced forms of SCLE are analogous in their clinical, serological and histological features. Drug-induced SCLE has been reported with various oral agents, but to our knowledge this is the first reported case due to a topical medication. A 34-year-old female foot masseuse presented with a 2-month history of scaly, erythematous lesions isolated to the dorsal hands and interdigital spaces. She had used topical terbinafine, a topical antifungal cream, to her clients’ feet for a number of years. ANA and anti-SSA/Ro antibodies were positive. Physical examination, serology and histopathology were consistent with SCLE. We propose that our patient's unique presentation of SCLE may be explained by a prolonged occupational exposure to topical terbinafine as a foot masseuse. While oral terbinafine is a drug known to cause drug-induced SCLE, to our knowledge, this is the first topically induced form of the disease.

Cancer risk in cutaneous lupus erythematosus: a population-based cohort study

OBJECTIVE

Immune dysregulation associated with chronic autoimmune diseases, such as SLE, has been associated with increased cancer risk. It is unclear whether isolated cutaneous lupus erythematosus (CLE) modifies cancer risk. We estimated the cumulative incidence of cancer in a population-based CLE cohort and compared the risk with a matched non-CLE cohort.

METHODS

All incident cases of CLE in Olmsted County, MN, USA between 1965 and 2005 were identified and followed to December 2013. Estimates for the cumulative incidence of any cancer and skin cancer in patients with CLE were derived and compared with an age-, sex- and calendar-year-matched non-CLE cohort using Cox models.

RESULTS

There were a total of 155 patients with CLE [age at diagnosis, 48 (sd 16) years; 65% females; BMI, 26.3 (sd 7.1) kg/m²; 40% smokers, 9% with diabetes]. During a median follow-up of 14.6 years, we observed 35 cases of incident cancer (including 10 cases of skin cancer). The cumulative 1-, 5- and 10-year incidence of any cancer after diagnosis of CLE was 1.4, 7.5 and 11.6%, respectively. Compared with matched non-CLE controls, the overall risk of malignancies was not increased in patients with CLE (smoking-adjusted hazard ratio = 1.29; 95% CI: 0.78, 2.13; P = 0.31). There was also no significant increase in risk of any skin cancer in patients with CLE (hazard ratio = 2.51; 95% CI: 0.91, 6.96; P = 0.16).

CONCLUSION

CLE is not associated with an increased risk of any cancers, including skin cancers, compared with the general population. However, the number of events was small, limiting the power of the study.

Cutaneous Lupus Erythematosus: An Update on Pathogenesis, Diagnosis and Treatment

Cutaneous lupus erythematosus (CLE) includes a broad range of dermatologic manifestations, which may or may not be associated with systemic disease. Recent studies in this area continue to shape our understanding of this disease and treatment options. Epidemiologic studies have found an incidence of CLE of 4.30 per 100,000, which approaches similar analysis for systemic lupus erythematosus (SLE). Although there have been extensive efforts to define SLE, the classification of CLE and its subgroups remains a challenge. Currently, diagnosis relies on clinical and laboratory findings as well as skin histology. The Cutaneous Lupus Area and Severity Index™ (CLASI™) is a validated measure of disease activity and damage. CLE pathogenesis is multifactorial and includes genetic contributions as well as effects of ultraviolet (UV) light. Immune dysregulation and aberrant cell signaling pathways through cytokine cascades are also implicated. Patient education and avoidance of triggers are key to disease prevention. Antimalarials and topical steroids continue to be the standard of care; however, immunosuppressants, thalidomide analogs and monoclonal antibodies are possible systemic therapies for the treatment of recalcitrant disease.

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.

Melanocortin peptides: potential targets in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease resulting in loss of self-tolerance with multiple organs, such as the kidney, skin, joints, and the central nervous system (CNS), being targeted. Numerous immunosuppressant therapies are currently being used for the treatment of SLE, but their clinical utility is somewhat variable because of the clinical heterogeneity. Melanocortins are a family of peptides derived from the common precursor protein pro-opiomelanocortin. These multifunctional peptides activate five subtypes of melanocortin receptors expressed on immune, skin, muscle, bone, and kidney cells and cells within the CNS. Melanocortin peptides have demonstrated a variety of biologic actions including immunomodulation, melanogenesis, and renoprotection. This review aims to introduce the melanocortin system and explore the mechanisms by which they may be beneficial in diseases such as SLE.

Topical clobetasol for the treatment of toxic epidermal necrolysis: study protocol for a randomized controlled trial

Background

Toxic epidermal necrolysis (TEN) is a rare systemic allergic drug eruption with high patient mortality. Currently, no established treatments have been shown to be effective for TEN beyond supportive care. Prior studies of systemic corticosteroids have yielded conflicting data, with some showing a possible benefit and others reporting in increased mortality. However, topical steroids have shown promise for treatment of ocular sequelae of TEN, such as scarring and vision loss. We have designed a randomized controlled trial to evaluate topical clobetasol for treatment of the epidermal manifestations of TEN. In addition, we propose genetic studies to characterize the TEN transcriptome and alterations in cutaneous gene expression that might occur following topical steroid treatment.

Methods/Design

This split-body randomized, double-blind, placebo-controlled Phase IIa proof-of-concept trial will evaluate the safety and efficacy of once-daily topical clobetasol applied to the skin of patients with TEN. This multicenter trial will recruit a total of 15 patients between the ages of 12 and 85 from the University of California Davis Medical Center and Shriners Hospital for Children inpatient burn units. Designated treatment areas on opposite sides of the body will be treated with blinded clobetasol 0.05 % ointment or control petrolatum ointment daily for 14 days. On day 3 of therapy, a biopsy will be taken from the treated area for genetic studies. The primary study aims will be to establish the safety of topical clobetasol treatment and determine the time to cessation of skin detachment for the control and clobetasol-treated areas. Secondary endpoints will evaluate efficacy using parameters such as time to 90 % re-epithelialization and percentage of affected skin at 0, 3, 6, 9, 12 and 15 days. Genomic DNA and RNA will be obtained from biopsy samples, to characterize the TEN transcriptome and identify changes in gene expression after topical steroid treatment.

Discussion

Topical steroids have shown promise for treating ocular complications of TEN, but to date have not been evaluated for cutaneous manifestations of the disease. This trial will investigate clinical and molecular outcomes of topical clobetasol application and hopefully provide insight into the disease pathophysiology.

Trial registration

ClinicalTrials.gov NCT02319616. https://clinicaltrials.gov/ct2/show/NCT02351037

Pathophysiology of cutaneous lupus erythematosus

The pathophysiology of cutaneous lupus erythematosus (CLE) encompasses the complex interactions between genetics, the environment, and cells and their products. Recent data have provided enhanced understanding of these interactions and the mechanism by which they cause disease. A number of candidate genes have been identified which increase the risk of developing CLE. Ultraviolet radiation, the predominant environmental exposure associated with CLE, appears to initiate CLE lesion formation by inducing apoptosis, precipitating autoantigen presentation, and promoting cellular production of specific cytokines. Autoantibodies are a well-known entity in CLE, but their exact role remains unclear. Finally, cells ranging from native skin cells to innate and adaptive immune cells produce cytokines and other molecules and play specific roles in lesion formation and perpetuation. Native skin cells implicated in CLE include keratinocytes and endothelial cells. Innate immune cells crucial to CLE pathophysiology include dendritic cells and neutrophils. The primary adaptive immune cells thought to be involved include Th1 cells, Th17 cells, cytotoxic T cells, and invariant natural killer T cells. Though the pathophysiology of CLE has yet to be fully characterized, current research provides direction for future research and therapies.

Genetics and novel aspects of therapies in systemic lupus erythematosus

Autoimmune diseases, such as rheumatoid arthritis, multiple sclerosis, autoimmune hepatitis and inflammatory bowel disease, have complex pathogeneses and the factors which cause these disorders are not well understood. But all have in common that they arise from a dysfunction of the immune system, interpreting self components as foreign antigens. Systemic lupus erythematosus (SLE) is one of these complex inflammatory disorders that mainly affects women and can lead to inflammation and severe damage of virtually any tissue and organ. Recently, the application of advanced techniques of genome-wide scanning revealed more genetic information about SLE than previously possible. These case-control or family-based studies have provided evidence that SLE susceptibility is based (with a few exceptions) on an individual accumulation of various risk alleles triggered by environmental factors and also help to explain the discrepancies in SLE susceptibility between different populations or ethnicities. Moreover, during the past years new therapies (autologous stem cell transplantation, B cell depletion) and improved conventional treatment options (corticosteroids, traditional and new immune-suppressants like mycophenolate mofetile) changed the perspective in SLE therapeutic approaches. Thus, this article reviews genetic aspects of this autoimmune disease, summarizes clinical aspects of SLE and provides a general overview of conventional and new therapeutic approaches in SLE.

The immunopathology of cutaneous lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that is characterized by the development of autoantibodies and immunologic attack of different organ systems, including the skin. This review aims to provide an overview of some of the pathogenic processes that may be important in the development of SLE, specifically cutaneous lupus erythematosus, and then illustrates how therapies might be tailored to modify these processes and treat disease.

TWEAK/Fn14 Signaling Involvement in the Pathogenesis of Cutaneous Disease in the MRL/lpr Model of Spontaneous Lupus

Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK, TNFSF12) and its sole receptor Fn14, belonging to the TNF ligand and receptor superfamilies respectively, are involved in cell survival and cytokine production. The role of TWEAK/Fn14 interactions in the pathogenesis of cutaneous lupus has not been explored. TWEAK treatment of murine PAM212 keratinocytes stimulated the secretion of RANTES via Fn14 and promoted apoptosis. Parthenolide, but not wortmanin or the MAPK inhibitor PD98059, significantly decreased production of RANTES, indicating that this effect of TWEAK is mediated via NF-κB signaling. UVB irradiation significantly upregulated the expression of Fn14 on keratinocytes in vitro and in vivo and increased RANTES production. MRL/lpr Fn14 knockout (KO) lupus mice were compared with MRL/lpr Fn14 wild-type (WT) mice to evaluate for any possible differences in the severity of cutaneous lesions and the presence of infiltrating immune cells. MRL/lpr Fn14 KO mice had markedly attenuated cutaneous disease as compared with their Fn14 WT littermates, as evidenced by the well-maintained architecture of the skin and significantly decreased skin infiltration of T cells and macrophages. Our data strongly implicate TWEAK/Fn14 signaling in the pathogenesis of the cutaneous manifestations in the MRL/lpr model of spontaneous lupus and suggest a possible target for therapeutic intervention.

CpGB DNA activates dermal macrophages and specifically recruits inflammatory monocytes into the skin

Toll-like receptor 9 (TLR9) drives innate immune responses after recognition of foreign or endogenous DNA containing unmethylated CpG motifs. DNA-mediated TLR9 activation is highly implicated in the pathogenesis of several autoimmune skin diseases, yet its contribution to the inflammation seen in these diseases remains unclear. In this study, TLR9 ligand, CpGB DNA, was administered to mice via a subcutaneous osmotic pump with treatment lasting 1 or 4 weeks. Gene expression and immunofluorescence analyses were used to determine chemokine expression and cell recruitment in the skin surrounding the pump outlet. CpGB DNA skin treatment dramatically induced a marked influx of CD11b+ F4/80+ macrophages, increasing over 4 weeks of treatment, and induction of IFNγ and TNFα expression. Chemokines, CCL2, CCL4, CCL5, CXCL9 and CXCL10, were highly induced in CpGB DNA-treated skin, although abrogation of these signalling pathways individually did not alter macrophage accumulation. Flow cytometry analysis showed that TLR9 activation in the skin increased circulating CD11b+ CD115+ Ly6C(hi) inflammatory monocytes following 1 week of CpGB DNA treatment. Additionally, skin-resident CD11b+ cells were found to initially take up subcutaneous CpGB DNA and propagate the subsequent immune response. Using diphtheria toxin-induced monocyte depletion mouse model, gene expression analysis demonstrated that CD11b+ cells are responsible for the CpGB DNA-induced cytokine and chemokine response. Overall, these data demonstrate that chronic TLR9 activation induces a specific inflammatory response, ultimately leading to a striking and selective accumulation of macrophages in the skin.

Genome-wide transcriptional profiling of chronic cutaneous lupus erythematosus (CCLE) peripheral blood identifies systemic alterations relevant to the skin manifestation

Major gaps remain regarding pathogenetic mechanisms underlying clinical heterogeneity in lupus erythematosus (LE). As systemic changes are likely to underlie skin specific manifestation, we analyzed global gene expression in peripheral blood of a small cohort of chronic cutaneous LE (CCLE) patients and healthy individuals. Unbiased hierarchical clustering distinguished patients from controls revealing a "disease" based signature. Functional annotation of the differentially expressed genes (DEGs) highlight enrichment of interferon related immune response and apoptosis signatures, along with other key pathways. There is a 26% overlap of the blood and lesional skin transcriptional profile from a previous analysis by our group. We identified four transcriptional "hot spots" at chromosomal regions harboring statistically increased numbers of DEGs which offer prioritized potential loci for downstream fine mapping studies in the search for CCLE specific susceptibility loci. Additionally, we uncover evidence to support both shared and distinct mechanisms for cutaneous and systemic manifestations of lupus.

Cutaneous lupus erythematosus: An update

Lupus erythematosus (LE) is a chronic, autoimmune, multisystem disease that displays many diverse symptoms in which localized cutaneous LE (CLE) is on one end of the spectrum and severe systemic LE (SLE) on the other end. The underlying cause of LE is unknown but the etiology is thought to be multifactorial and polygenic. CLE is a disfiguring, chronic skin disease, with a significant impact on the patients’ everyday life. CLE are further divided into three main subsets: Acute CLE (ACLE), subacute CLE (SCLE) and chronic CLE (CCLE), where classic discoid LE (DLE) is the most common form. These subsets are defined by clinical symptoms, average duration of symptoms and histological and serological findings, although, the three subtypes can have overlapping clinical features. CLE patients display well-defined skin lesions, often in sun-exposed areas. The disease often has a chronic and relapsing course that can be induced or aggravated by UV light. It is important to confirm a CLE diagnosis histopathologically by a biopsy and in that there are several differential diagnoses and because CLE is a chronic disease in which regular follow-up is important and systemic treatment is sometimes indicated.

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.

Update on pathogenesis and treatment of CLE

PURPOSE OF REVIEW

Cutaneous Lupus Erythematous (CLE) is an autoimmune disease in which patients may present with isolated skin findings or have CLE associated with underlying systemic disease. The most significant recent studies on its pathogenesis and therapeutic management are reviewed here.

RECENT FINDINGS

Patients with subacute and Discoid Lupus Erythematous had elevated Interferon score, about a third of all cases of SCLE could be attributed to previous drug exposure, and smoking may be more closely associated with CLE than Systemic Lupus Erythematous (SLE). An underlying genetic defect in some subsets of CLE patients may also be shared with SLE. Efficacy of antimalarial therapy is enhanced by increasing treatment duration or maintaining higher blood drug concentrations. Combination antimalarials that include quinacrine, thalidomide analogs, and Mycophenalate Mofetil may also be effective in refractory CLE.

SUMMARY

The pathogenesis of CLE remains unclear, and is likely multifactorial. Identified associations with subsets of CLE suggest future research questions in CLE pathogenesis. Subsets of CLE associated with interface dermatitis may share an underlying genetic defect in interferon signaling with SLE. The Cutaneous Lupus Disease Area and Severity Index is a valuable and widely used tool allowing standardized assessment and reporting of cutaneous disease activity and damage. More evidence is available to guide treatment of refractory CLE, but larger studies are needed.

VIDEO ABSTRACT

http://links.lww.com/COR/A4.

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.

Chilblain lupus erythematosus

Chilblain lupus erythematosus is a rare form of chronic cutaneous lupus erythematosus. It is characterised by purple plaques/nodules and oedematous skin mainly around the acral regions of the body, which are most exposed to the cold. In this paper we report a case of chilblain lupus erythematosus that was diagnosed using the Mayo Clinic Diagnostic Criteria and its successful treatment with hydroxychloroquine.

Cutaneous lupus after herpes zoster: isomorphic, isotopic, or both?

Koebner isomorphic response describes the phenomenon of histopathologically identical skin lesions of a preceding cutaneous disease appearing in sites of trauma. Wolf isotopic response describes the phenomenon of a new skin disease appearing in the site of an unrelated cutaneous disease. Neither of the phenomena has been reported in relation to systemic lupus erythematosus. This report describes a 17-year-old girl with systemic lupus erythematosus exhibiting particularly severe cutaneous involvement confined primarily to sun-exposed areas presenting with a dermatomal band of atrophic, scaling, erythematous papules, and plaques on her left shoulder extending down her left arm after herpes zoster eruption. The histopathologil result showed lupus erythematosus. This phenomenon is best considered as a Koebner isomorphic response, although Wolf isotopic response has some clinical relevance as well. Koebner isomorphic and Wolf isotopic responses are discussed as related to this case.

Immunologic and genetic considerations of cutaneous lupus erythematosus: a comprehensive review

Cutaneous lupus erythematosus (CLE) refers to those subtypes of lupus erythematosus (LE) that have predominantly skin manifestations. Discoid lupus erythematosus (DLE), subacute cutaneous lupus erythematosus (SCLE), LE panniculitis (LEP) and lupus erythematosus tumidus (LET) all fall into the category of CLE. The pathogenesis of CLE is likely multifactorial. UV irradiation has been shown to induce keratinocyte apoptosis. Impaired clearance of apoptotic cells is a potential mechanism for the development of CLE. UV irradiation can also induce externalization of autoantigens such as Ro/SSA, exposing them to circulating autoantibodies. Some drugs have been associated with CLE. Possible mechanisms include stimulation of an immune response through disruption of central tolerance and altered T cell function. T17 cells may also play a role in the pathogenesis of CLE as they have been detected in skin lesions of LE. Treg cells have been found to be decreased in LE lesions, which may contribute to the breakdown of self-tolerance. Epidermal Langerhans cells are reduced in CLE while plasmacytoid DCs are increased in the lesions of CLE, suggesting that DCs may also play an important role in the pathogenesis of CLE. Type I IFN- and TNF-α are both upregulated in lesions of CLE. Other cytokines such as IL-6 and IL-17 are also implicated in the pathogenesis of CLE. Cellular and cytokine networks can be impacted by environmental factors and genetic variations and this can result in an increased risk of developing autoimmune diseases such as CLE.

NETs: the missing link between cell death and systemic autoimmune diseases?

For almost 20 years, apoptosis and secondary necrosis have been considered the major source of autoantigens and endogenous adjuvants in the pathogenic model of systemic autoimmune diseases. This focus is justified in part because initial evidence in systemic lupus erythematosus (SLE) guided investigators toward the study of apoptosis, but also because other forms of cell death were unknown. To date, it is known that many other forms of cell death occur, and that they vary in their capacity to stimulate as well as inhibit the immune system. Among these, NETosis (an antimicrobial form of death in neutrophils in which nuclear material is extruded from the cell forming extracellular traps), is gaining major interest as a process that may trigger some of the immune features found in SLE, granulomatosis with polyangiitis (formerly Wegener’s granulomatosis) and Felty’s syndrome. Although there have been volumes of very compelling studies published on the role of cell death in autoimmunity, no unifying theory has been adopted nor have any successful therapeutics been developed based on this important pathway. The recent inclusion of NETosis into the pathogenic model of autoimmune diseases certainly adds novel insights into this paradigm, but also reveals a previously unappreciated level of complexity and raises many new questions. This review discusses the role of cell death in systemic autoimmune diseases with a focus on apoptosis and NETosis, highlights the current short comings in our understanding of the vast complexity of cell death, and considers the potential shift in the cell death paradigm in autoimmunity. Understanding this complexity is critical in order to develop tools to clearly define the death pathways that are active in systemic autoimmune diseases, identify drivers of disease propagation, and develop novel therapeutics.

Visualization of epidermal and dermal alteration in papulonodular mucinosis by multiphoton microscopy

Papulonodular mucinosis (PM) is a cutaneous clue to the presence and activity of silent lupus erythematosus (LE), but the exact pathogenesis is still under secret. Moreover, the currently available treatments for PM are not satisfactory. To demonstrate the possibility of multiphoton microscopy (MPM) to trace the pathological state of PM and evaluate the treatment efficacy, epidermal and dermal alteration in skin lesion with PM before and after treatment was examined using MPM. Microstructure of epidermis as well as content and distribution of collagen and elastin in dermis were quantified to characterize the pathological states of PM. The results showed significant morphological difference between skin lesion before and after treatment, indicating the possibility of MPM to assess the therapeutic efficacy. With the advancement on MPM miniaturization and enhancement of contrast and depth of imaging, the MPM technique can be applied in in vivo tracking PM formation and progression, and leading the better understanding the PM pathogenesis and mechanism of response to any treatment, helping to establish novel effective therapies for PM.

Citalopram-induced subacute cutaneous lupus erythematosus -- first case and review concerning photosensitivity in selective serotonin reuptake inhibitors

OBJECTIVE

This report describes a case of subacute cutaneous lupus erythematosus (SCLE) in a patient treated with citalopram and discusses evidence linking selective serotonin reuptake inhibitors (SSRIs) to the induction of photosensitivity.

METHOD

Case report and review of published literature.

RESULTS

A 71-year-old woman with major depression developed 2 days after intake of 20 mg citalopram a strongly itching and largely dimensioned confluencing erythema with infiltrations and blisters all over the trunk with fever and malaise. Histological and laboratory investigations were consistent with the diagnosis of SCLE. After stopping citalopram intake, dermatologic symptoms significantly improved within 2 weeks. SSRIs have been associated with 14 cases of adverse cutaneous events as a result of SSRI-induced photosensitivity. No case of SSRI-induced SCLE has been described.

CONCLUSION

In clinical practice, indication and dosage of citalopram and other SSRIs should be carefully monitored. In the case of a SSRI-induced photosensitivity, medication can be switched to an antidepressant from another class.