Brief Report: Pharmacodynamics, Safety, and Clinical Efficacy of AMG 811, a Human Anti-Interferon-γ Antibody, in Patients With Discoid Lupus Erythematosus

New and emerging therapies for systemic lupus erythematosus

Systemic Lupus Erythematosus (SLE) and lupus nephritis treatment is still based on non-specific immune suppression despite the first biological therapy for the disease having been approved more than a decade ago. Intense basic and translational research has uncovered a multitude of pathways that are actively being evaluated as treatment targets in SLE and lupus nephritis, with two new medications receiving FDA approval in the last 3 years. Herein we provide an overview of targeted therapies for SLE including medications targeting the B lymphocyte compartment, intracellular signaling, co-stimulation, and finally the interferons and other cytokines.

Uncoupling interferons and the interferon signature explains clinical and transcriptional subsets in SLE

Systemic lupus erythematosus (SLE) displays a hallmark interferon (IFN) signature. Yet, clinical trials targeting type I IFN (IFN-I) have shown variable efficacy, and blocking IFN-II failed to treat SLE. Here, we show that IFN type levels in SLE vary significantly across clinical and transcriptional endotypes. Whereas skin involvement correlated with IFN-I alone, systemic features like nephritis associated with co-elevation of IFN-I, IFN-II, and IFN-III, indicating additive IFN effects in severe SLE. Notably, while high IFN-II/-III levels without IFN-I had a limited effect on disease activity, IFN-II was linked to IFN-I-independent transcriptional profiles (e.g., OXPHOS and CD8+GZMH+ cells), and IFN-III enhanced IFN-induced gene expression when co-elevated with IFN-I. Moreover, dysregulated IFNs do not explain the IFN signature in 64% of patients or clinical manifestations including cytopenia, serositis, and anti-phospholipid syndrome, implying IFN-independent endotypes in SLE. This study sheds light on mechanisms underlying SLE heterogeneity and the variable response to IFN-targeted therapies in clinical trials.

Uncoupling interferons and the interferon signature explain clinical and transcriptional subsets in SLE

Interferons (IFN) are thought to be key players in systemic lupus erythematosus (SLE). The unique and interactive roles of the different IFN families in SLE pathogenesis, however, remain poorly understood. Using reporter cells engineered to precisely quantify IFN-I, IFN-II and IFN-III activity levels in serum/plasma, we found that while IFNs play essential role in SLE pathogenesis and disease activity, they are only significant in specific subsets of patients. Interestingly, whereas IFN-I is the main IFN that governs disease activity in SLE, clinical subsets are defined by the co-elevation of IFN-II and IFN-III. Thus, increased IFN-I alone was only associated with cutaneous lupus. In contrast, systemic features, such as nephritis, were linked to co-elevation of IFN-I plus IFN-II and IFN-III, implying a synergistic effect of IFNs in severe SLE. Intriguingly, while increased IFN-I levels were strongly associated with IFN-induced gene expression (93.5%), in up to 64% of cases, the IFN signature was not associated with IFN-I. Importantly, neither IFN-II nor IFN-III explained IFN-induced gene expression in patients with normal IFN-I levels, and not every feature in SLE was associated with elevated IFNs, suggesting IFN-independent subsets in SLE. Together, the data suggest that, unlike the IFN signature, direct quantification of bioactive IFNs can identify pathogenic and clinically relevant SLE subsets amenable for precise anti-IFN therapies. Since IFN-I is only elevated in a subset of SLE patients expressing the IFN signature, this study explains the heterogeneous response in clinical trials targeting IFN-I, where patients were selected based on IFN-induced gene expression rather than IFN-I levels.

An update on the management of refractory cutaneous lupus erythematosus

Management of cutaneous lupus erythematosus (CLE) involves a combination of preventive measures, topical and systemic drugs, fairly similar for the different subtypes. Although guidelines exist, to date, no specific drugs have been specifically licensed for CLE. Antimalarials remain the first-line systemic treatment, but many patients do not respond, making refractory lupus a challenge for clinicians. The choice of alternative medication should be based on effectiveness, safety and cost. Most of the available drugs for CLE have been adapted from systemic lupus erythematosus (SLE) treatment but the existing literature is limited to small studies and evidence often lacks. As knowledge of pathogenesis of both CLE and SLE is improving, promising new therapies are emerging. In this review, we discuss the available medications, focusing on the novelties under development for CLE.

Advancements in the Treatment of Cutaneous Lupus Erythematosus and Dermatomyositis: A Review of the Literature

Background

Cutaneous lupus erythematosus (CLE) and dermatomyositis (DM) are autoimmune diseases that present with a wide variety of cutaneous manifestations. In both cases, first-line therapy includes topical corticosteroids. Patients may present with more widespread disease requiring systemic treatments, including corticosteroids, traditional immunosuppressants, or antimalarials. Due to their complex nature, both CLE and DM remain difficult to treat and continue to cause significant distress to patients.

Objective

To summarize the most recent literature on the safety and efficacy of novel treatment modalities for CLE and DM.

Methods

A literature search was conducted on PubMed using search terms “(dermatomyositis) AND (treatment)” and “(cutaneous lupus) AND (treatment)”. Additional search terms included specific names of biologic agents, phosphodiesterase inhibitors (apremilast), and JAK inhibitors.

Results

JAK inhibitors, PDE-4 inhibitors, and biologics have shown promise in reducing cutaneous symptoms of both CLE and DM, including reduction in SLE Disease Activity Index 2000 (SLEDAI-2K), Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI), British Isles Lupus Assessment Group (BILAG), Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI), and Disease Activity Score (DAS).

Conclusion

While there have been recent advancements in the treatment for CLE and DM, further research and clinical trials are required to better elucidate which therapy is best for individual patients.

IFN-γ, should not be ignored in SLE

Systemic lupus erythematosus (SLE) is a typical autoimmune disease with a complex pathogenesis and genetic predisposition. With continued understanding of this disease, it was found that SLE is related to the interferon gene signature. Most studies have emphasized the important role of IFN-α in SLE, but our previous study suggested a nonnegligible role of IFN-γ in SLE. Some scholars previously found that IFN-γ is abnormally elevated as early as before the classification of SLE and before the emergence of autoantibodies and IFN-α. Due to the large overlap between IFN-α and IFN-γ, SLE is mostly characterized by expression of the IFN-α gene after onset. Therefore, the role of IFN-γ in SLE may be underestimated. This article mainly reviews the role of IFN-γ in SLE and focuses on the nonnegligible role of IFN-γ in SLE to gain a more comprehensive understanding of the disease.

Trial of Anti-BDCA2 Antibody Litifilimab for Cutaneous Lupus Erythematosus

BACKGROUND

Blood dendritic cell antigen 2 (BDCA2) is a receptor that is exclusively expressed on plasmacytoid dendritic cells, which are implicated in the pathogenesis of lupus erythematosus. Whether treatment with litifilimab, a humanized monoclonal antibody against BDCA2, would be efficacious in reducing disease activity in patients with cutaneous lupus erythematosus has not been extensively studied.

METHODS

In this phase 2 trial, we randomly assigned adults with histologically confirmed cutaneous lupus erythematosus with or without systemic manifestations in a 1:1:1:1 ratio to receive subcutaneous litifilimab (at a dose of 50, 150, or 450 mg) or placebo at weeks 0, 2, 4, 8, and 12. We used a dose-response model to assess whether there was a response across the four groups on the basis of the primary end point, which was the percent change from baseline to 16 weeks in the Cutaneous Lupus Erythematosus Disease Area and Severity Index-Activity score (CLASI-A; scores range from 0 to 70, with higher scores indicating more widespread or severe skin involvement). Safety was also assessed.

RESULTS

A total of 132 participants were enrolled; 26 were assigned to the 50-mg litifilimab group, 25 to the 150-mg litifilimab group, 48 to the 450-mg litifilimab group, and 33 to the placebo group. Mean CLASI-A scores for the groups at baseline were 15.2, 18.4, 16.5, and 16.5, respectively. The difference from placebo in the change from baseline in CLASI-A score at week 16 was -24.3 percentage points (95% confidence interval [CI] -43.7 to -4.9) in the 50-mg litifilimab group, -33.4 percentage points (95% CI, -52.7 to -14.1) in the 150-mg group, and -28.0 percentage points (95% CI, -44.6 to -11.4) in the 450-mg group. The least squares mean changes were used in the primary analysis of a best-fitting dose-response model across the three drug-dose levels and placebo, which showed a significant effect. Most of the secondary end points did not support the results of the primary analysis. Litifilimab was associated with three cases each of hypersensitivity and oral herpes infection and one case of herpes zoster infection. One case of herpes zoster meningitis occurred 4 months after the participant received the last dose of litifilimab.

CONCLUSIONS

In a phase 2 trial involving participants with cutaneous lupus erythematosus, treatment with litifilimab was superior to placebo with regard to a measure of skin disease activity over a period of 16 weeks. Larger and longer trials are needed to determine the effect and safety of litifilimab for the treatment of cutaneous lupus erythematosus. (Funded by Biogen; LILAC ClinicalTrials.gov number, NCT02847598.).

Emerging Therapies in Cutaneous Lupus Erythematosus

Cutaneous lupus erythematosus (CLE) is an autoimmune disease that can occur with or without underlying systemic lupus erythematosus (SLE) and often has a profoundly negative impact on patient quality of life. There is substantial need for new and more effective therapies to treat CLE. CLE has a multifactorial pathogenesis that involves several key immune cells and pathways, including abnormalities in innate (e.g., type 1 interferon pathways) and adaptive immune responses (e.g., B and T cell autoreactivity), presenting multiple opportunities for more targeted therapies that do not require immunosuppression. Here we review several emerging therapies and their efficacy in CLE. Anifrolumab and belimumab have both been approved for the treatment of SLE in recent years, and clinical trial evidence suggests some forms of CLE may improve with these agents. Therapies currently in development that are being evaluated with CLE-specific outcome measures include BIIB059 and VIB7734, which target plasmacytoid dendritic cells (pDCs), and iberdomide, a cereblon modulator. These novel therapies all have previously demonstrated clinical benefit in some forms of CLE. Other therapies which target molecules believed to play a role in CLE pathogenesis, such as Janus kinases (JAKs), spleen tyrosine kinase (SYK), interferon γ (IFNγ), IL-12, and IL-23, have been evaluated in lupus clinical trials with skin-specific outcomes but failed to meet their primary endpoints.

Current Concepts on Pathogenic Mechanisms and Histopathology in Cutaneous Lupus Erythematosus

Cutaneous lupus erythematosus (CLE) is an interferon (IFN)-driven autoimmune disease that may be limited to the skin or can be associated with systemic lupus erythematosus (SLE). CLE occurs in several morphologic subtypes ranging from isolated, disc-shaped plaques to disseminated skin lesions. The typical histopathologic pattern of skin lesions is named interface dermatitis and characterized by a lymphocytic infiltrate and necroptotic keratinocytes at the dermo-epidermal junction. Other histopathologic patterns primarily involve the dermis or subcutis, depending on the subtype. One critical mechanism in CLE is the chronic reactivation of innate and adaptive immune pathways. An important step in this process is the recognition of endogenous nucleic acids released from dying cells by various pattern recognition receptors (PRRs), including Toll-like receptors (TLRs) and other cytosolic receptors. Crucial cells in CLE pathogenesis comprise plasmacytoid dendritic cells (pDCs) as major producers of type I IFN, T cells exerting cytotoxic effects, and B cells, previously believed to contribute via secretion of autoantibodies. However, B cells are increasingly considered to have additional functions, supported by studies finding them to occur in highest numbers in chronic discoid lupus erythematosus (CDLE), a subtype in which autoantibodies are often absent. More precise knowledge of how CLE subtypes differ pathophysiologically may allow a tailored pharmacotherapy in the future, taking into account the specific molecular signature in relation to the morphologic subtype.

Machine learning reveals distinct gene signature profiles in lesional and nonlesional regions of inflammatory skin diseases

Analysis of gene expression from cutaneous lupus erythematosus, psoriasis, atopic dermatitis, and systemic sclerosis using gene set variation analysis (GSVA) revealed that lesional samples from each condition had unique features, but all four diseases displayed common enrichment in multiple inflammatory signatures. These findings were confirmed by both classification and regression tree analysis and machine learning (ML) models. Nonlesional samples from each disease also differed from normal samples and each other by ML. Notably, the features used in classification of nonlesional disease were more distinct than their lesional counterparts, and GSVA confirmed unique features of nonlesional disease. These data show that lesional and nonlesional skin samples from inflammatory skin diseases have unique profiles of gene expression abnormalities, especially in nonlesional skin, and suggest a model in which disease-specific abnormalities in "prelesional" skin may permit environmental stimuli to trigger inflammatory responses leading to both the unique and shared manifestations of each disease.

Emerging Therapeutics in the Management of Connective Tissue Disease. Part I. Lupus Erythematosus and Sjögren's Syndrome

The management of connective tissue diseases is dramatically evolving with the advent of biologics and novel oral systemic therapeutics. Despite involvement in the care of these complex patients, there is a knowledge gap in the field of dermatology regarding these emerging agents. The first article in this continuing medical education series discusses new and emerging therapeutics for lupus erythematosus and Sjögren's syndrome that target cells, intracellular signaling pathways, and cytokines.

Cutaneous Lupus Erythematosus and Dermatomyositis: Utilizing Assessment Tools for Treatment Efficacy

There have been important developments in defining cutaneous lupus erythematosus and dermatomyositis. The skin manifestations of these two diseases have a profound impact on QOL, with both emotional and symptomatic impacts that are important to address. The proliferation of potential therapeutic targets has made it important to make sure that these diseases are defined in a way that they can be included in translational and clinical studies of both localized and systemic forms of the diseases. There are now validated disease tools and QOL studies that are facilitating current and future scientific and therapeutic developments.

Advances in therapeutic targets-related study on systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic and autoimmunity-mediated diffuse connective tissue disease. The mainstay of treatments for SLE mainly relies on corticosteroids and immunosuppressants, which have a series of unavoidable side effects. Therefore, it is of fundamental importance to search novel therapeutic targets for better treatment with favorable efficacy and minor side effects. Recent studies shed light on potential therapeutic targets for SLE, mainly covering the followings: B-cell/plasmocyte-related targets [B cell activating factor (BAFF), a proliferation-inducing ligand (APRIL), CD20, CD22, CD19/FcγRIIb, Bruton tyrosine kinase (Btk), and proteasome], T cell-related targets [calcineurin, mammalian target of rapamycin (mTOR), regulatory factor X1 (RFX1), and Rho kinase], macrophage-related targets (macrophage migration inhibitory factor), intracellular signaling molecules, cytokines (cereblon, histone deacetylase 6, Janus activated kinase/signal transducer and activator of transcription), co-stimulating factors (CD28/B7, CD40/CD154), IgE autoantibody, and gut microbiome. Among them, belimumab (a humanized monoclonal antibody against B-lymphocyte stimulator) and telitacicept (a recombinant human B-lymphocyte stimulator receptor-antibody fusion protein) have been sequentially approved for the clinical treatment of SLE in China. A variety of new targeted-therapy drugs are in the Phase 2 or Phase 3 clinical trials,among which anifrolumab (a human monoclonal antibody against type I interferon receptor subunit 1) has completed a Phase 3 clinical trial with good responses achieved, although its incidence of herpes zoster is higher than that in the control group. The research progress in both molecular mechanisms and new drug development for different therapeutic targets have greatly promoted our better and in-depth understanding of the pathogenesis of SLE, and have also reflected the complexity and heterogeneity of the disease. Successful development and clinical application of more novel therapies would no doubt usher in a new era of individualized treatment for SLE in the future.

Targeting interferon-γ in hyperinflammation: opportunities and challenges

Interferon-γ (IFNγ) is a pleiotropic cytokine with multiple effects on the inflammatory response and on innate and adaptive immunity. Overproduction of IFNγ underlies several, potentially fatal, hyperinflammatory or immune-mediated diseases. Several data from animal models and/or from translational research in patients point to a role of IFNγ in hyperinflammatory diseases, such as primary haemophagocytic lymphohistiocytosis, various forms of secondary haemophagocytic lymphohistiocytosis, including macrophage activation syndrome, and cytokine release syndrome, all of which are often managed by rheumatologists or in consultation with rheumatologists. Given the effects of IFNγ on B cells and T follicular helper cells, a role for IFNγ in systemic lupus erythematosus pathogenesis is emerging. To improve our understanding of the role of IFNγ in human disease, IFNγ-related biomarkers that are relevant for the management of hyperinflammatory diseases are progressively being identified and studied, especially because circulating levels of IFNγ do not always reflect its overproduction in tissue. These biomarkers include STAT1 (specifically the phosphorylated form), neopterin and the chemokine CXCL9. IFNγ-neutralizing agents have shown efficacy in the treatment of primary haemophagocytic lymphohistiocytosis in clinical trials and initial promising results have been obtained in various forms of secondary haemophagocytic lymphohistiocytosis, including macrophage activation syndrome. In clinical practice, there is a growing body of evidence supporting the usefulness of circulating CXCL9 levels as a biomarker reflecting IFNγ production.

Cytokines as Biomarkers in Systemic Lupus Erythematosus: Value for Diagnosis and Drug Therapy

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease. The disease is characterized by activation and dysregulation of both the innate and the adaptive immune systems. The autoimmune response targets self-molecules including cell nuclei, double stranded DNA and other intra and extracellular structures. Multiple susceptibility genes within the immune system have been identified, as well as disturbances in different immune pathways. SLE may affect different organs and organ systems, and organ involvement is diverse among individuals. A universal understanding of pathophysiological mechanism of the disease, as well as directed therapies, are still missing. Cytokines are immunomodulating molecules produced by cells of the immune system. Interferons (IFNs) are a broad group of cytokines, primarily produced by the innate immune system. The IFN system has been observed to be dysregulated in SLE, and therefore IFNs have been extensively studied with a hope to understand the disease mechanisms and identify novel targeted therapies. In several autoimmune diseases identification and subsequent blockade of specific cytokines has led to successful therapies, for example tumor necrosis factor-alpha (TNF-α) inhibition in rheumatoid arthritis. Authors of this review have sought corresponding developments in SLE. In the current review, we cover the actual knowledge on IFNs and other studied cytokines as biomarkers and treatment targets in SLE.

A review on the role of chemokines in the pathogenesis of systemic lupus erythematosus

Chemokines are a group of cytokines with low molecular weight that principally direct chemotaxis of target cells. They have prominent roles in the pathogenesis systemic lupus erythematosus (SLE) and related complications particularly lupus nephritis. These molecules not only induce autoimmune responses in the organs of patients, but also can amplify the induced inflammatory responses. Although chemokine family has at least 46 identified members, the role of a number of these molecules have been more clarified in SLE patients or animal models of this disorder. In the current paper, we review the role of CCL2, CCL3, CCL4, CCL11, CCL20, CXCL1, CXCL2, CXCL8, CXCL10, CXCL12 and CXCL13 in the pathogenesis of SLE.

Recent Insight on the Management of Lupus Erythematosus Alopecia

Lupus erythematosus (LE) is a chronic autoimmune condition with a wide spectrum of clinical presentations. Alopecias, both non-scarring and scarring, frequently occur in the context of LE and can assume several different patterns. Furthermore, alopecia occurring with LE may be considered LE-specific if LE-specific features are present on histology; otherwise, alopecia is considered non-LE-specific. Non-scarring alopecia is highly specific to systemic LE (SLE), and therefore has been regarded as a criterion for the diagnosis of SLE. Variants of cutaneous LE (CLE), including acute, subacute, and chronic forms, are also capable of causing hair loss, and chronic CLE is an important cause of primary cicatricial alopecia. Other types of hair loss not specific to LE, including telogen effluvium, alopecia areata, and anagen effluvium, may also occur in a patient with lupus. Lupus alopecia may be difficult to treat, particularly in cases that have progressed to scarring. The article summarizes the types of lupus alopecia and recent insight regarding their management. Data regarding the management of lupus alopecia are sparse and limited to case reports, and therefore, many studies including in this review report the efficacy of treatments on CLE as a broader entity. In general, for patients with non-scarring alopecia in SLE, management is aimed at controlling SLE activity with subsequent hair regrowth. Topical medications can be used to expedite recovery. Prompt treatment is crucial in the case of chronic CLE due to potential for scarring and irreversible damage. First-line therapies for CLE include topical corticosteroids and oral antimalarials, with or without oral corticosteroids as bridging therapy. Second and third-line systemic treatments for CLE include methotrexate, retinoids, dapsone, mycophenolate mofetil, and mycophenolate acid. Additional topical and systemic medications as well as physical modalities used for the treatment of lupus alopecia and CLE are discussed herein.

Interventions for cutaneous disease in systemic lupus erythematosus

BACKGROUND

Lupus erythematosus is an autoimmune disease with significant morbidity and mortality. Cutaneous disease in systemic lupus erythematosus (SLE) is common. Many interventions are used to treat SLE with varying efficacy, risks, and benefits.

OBJECTIVES

To assess the effects of interventions for cutaneous disease in SLE.

SEARCH METHODS

We searched the following databases up to June 2019: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, Wiley Interscience Online Library, and Biblioteca Virtual em Saude (Virtual Health Library). We updated our search in September 2020, but these results have not yet been fully incorporated.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of interventions for cutaneous disease in SLE compared with placebo, another intervention, no treatment, or different doses of the same intervention. We did not evaluate trials of cutaneous lupus in people without a diagnosis of SLE.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Primary outcomes were complete and partial clinical response. Secondary outcomes included reduction (or change) in number of clinical flares; and severe and minor adverse events. We used GRADE to assess the quality of evidence.

MAIN RESULTS

Sixty-one RCTs, involving 11,232 participants, reported 43 different interventions. Trials predominantly included women from outpatient clinics; the mean age range of participants was 20 to 40 years. Twenty-five studies reported baseline severity, and 22 studies included participants with moderate to severe cutaneous lupus erythematosus (CLE); duration of CLE was not well reported. Studies were conducted mainly in multi-centre settings. Most often treatment duration was 12 months. Risk of bias was highest for the domain of reporting bias, followed by performance/detection bias. We identified too few studies for meta-analysis for most comparisons. We limited this abstract to main comparisons (all administered orally) and outcomes. We did not identify clinical trials of other commonly used treatments, such as topical corticosteroids, that reported complete or partial clinical response or numbers of clinical flares. Complete clinical response Studies comparing oral hydroxychloroquine against placebo did not report complete clinical response. Chloroquine may increase complete clinical response at 12 months' follow-up compared with placebo (absence of skin lesions) (risk ratio (RR) 1.57, 95% confidence interval (CI) 0.95 to 2.61; 1 study, 24 participants; low-quality evidence). There may be little to no difference between methotrexate and chloroquine in complete clinical response (skin rash resolution) at 6 months' follow-up (RR 1.13, 95% CI 0.84 to 1.50; 1 study, 25 participants; low-quality evidence). Methotrexate may be superior to placebo with regard to complete clinical response (absence of malar/discoid rash) at 6 months' follow-up (RR 3.57, 95% CI 1.63 to 7.84; 1 study, 41 participants; low-quality evidence). At 12 months' follow-up, there may be little to no difference between azathioprine and ciclosporin in complete clinical response (malar rash resolution) (RR 0.83, 95% CI 0.46 to 1.52; 1 study, 89 participants; low-quality evidence). Partial clinical response Partial clinical response was reported for only one key comparison: hydroxychloroquine may increase partial clinical response at 12 months compared to placebo, but the 95% CI indicates that hydroxychloroquine may make no difference or may decrease response (RR 7.00, 95% CI 0.41 to 120.16; 20 pregnant participants, 1 trial; low-quality evidence). Clinical flares Clinical flares were reported for only two key comparisons: hydroxychloroquine is probably superior to placebo at 6 months' follow-up for reducing clinical flares (RR 0.49, 95% CI 0.28 to 0.89; 1 study, 47 participants; moderate-quality evidence). At 12 months' follow-up, there may be no difference between methotrexate and placebo, but the 95% CI indicates there may be more or fewer flares with methotrexate (RR 0.77, 95% CI 0.32 to 1.83; 1 study, 86 participants; moderate-quality evidence). Adverse events Data for adverse events were limited and were inconsistently reported, but hydroxychloroquine, chloroquine, and methotrexate have well-documented adverse effects including gastrointestinal symptoms, liver problems, and retinopathy for hydroxychloroquine and chloroquine and teratogenicity during pregnancy for methotrexate.

AUTHORS' CONCLUSIONS

Evidence supports the commonly-used treatment hydroxychloroquine, and there is also evidence supporting chloroquine and methotrexate for treating cutaneous disease in SLE. Evidence is limited due to the small number of studies reporting key outcomes. Evidence for most key outcomes was low or moderate quality, meaning findings should be interpreted with caution. Head-to-head intervention trials designed to detect differences in efficacy between treatments for specific CLE subtypes are needed. Thirteen further trials are awaiting classification and have not yet been incorporated in this review; they may alter the review conclusions.

Gordon R, Branigan P, Lipsky P, van Vollenhoven R, Hahn BH, Tsokos GC, Chevrier M, Rose S, Baribaud F, Jordan J. Suppression of Serum Interferon-γ Levels as a Potential Measure of Response to Ustekinumab Treatment in Patients With Systemic Lupus Erythematosus

OBJECTIVE

In a previously reported phase II randomized, placebo-controlled, interventional trial, we demonstrated that treatment with ustekinumab, an anti-interleukin-12 (IL-12)/IL-23 p40 neutralizing monoclonal antibody, improved global and organ-specific measures of disease activity in patients with active systemic lupus erythematosus (SLE). Utilizing the biomarker data from this phase II clinical study, we sought to determine whether modulation of the expression of IL-12, IL-23, or both cytokines by ustekinumab is associated with clinical efficacy in patients with SLE.

METHODS

This phase II randomized, placebo-controlled study enrolled 102 patients with autoantibody-positive SLE whose disease remained active despite standard-of-care therapy. Patients were randomized at a 3:2 ratio to receive ~6 mg/kg ustekinumab intravenously or placebo at week 0, followed by subcutaneous injections of 90 mg ustekinumab or placebo every 8 weeks, with placebo crossover to 90 mg ustekinumab every 8 weeks. The SLE Responder Index 4 (SRI-4) at week 24 was used to determine which patients could be classified as ustekinumab responders and which could be classified as nonresponders. In addition to measurements of p40 and IL-23, serum levels of interferon-γ (IFNγ), IL-17A, IL-17F, and IL-22, as a proxy for the IL-12 and IL-23 pathways, were quantified by immunoassay.

RESULTS

Changes in the serum levels of IL-17A, IL-17F, and IL-22 at different time points after treatment were not consistently significantly associated with an SRI-4 clinical response to ustekinumab in patients with SLE. In contrast, an SRI-4 response to ustekinumab was significantly associated (P < 0.01) with durable reductions in the serum IFNγ protein levels at several time points relative to baseline, which was not observed in ustekinumab nonresponders or patients who received placebo.

CONCLUSION

While not diminishing a potential role of IL-23, these serum biomarker assessments indicate that IL-12 blockade has an important role in the mechanism of action of ustekinumab treatment in patients with SLE.

The CLASI, a validated tool for the evaluation of skin disease in lupus erythematosus: a narrative review

Cutaneous lupus erythematosus (CLE) can present with or without features of systemic lupus erythematosus (SLE), with estimates of the incidence of isolated skin disease almost equaling the incidence of those with systemic disease. However, despite the impact CLE has on a patient’s quality of life (QoL), there has been no US Food and Drug Administration (FDA) approved treatment for the disease in the past 50 years. In addition, patients with skin predominant LE are often excluded from clinical SLE trials. In the rare trials that include patients with skin predominant LE, disease activity and progression in the skin are often difficult to evaluate using multi-organ outcome measures. The need for new therapies for CLE and the lack of focus on skin outcomes has led to the development of the Cutaneous Lupus Disease Area and Severity Index (CLASI), a validated organ-specific outcome measure that is not only responsive to change in disease activity and damage but also correlated to changes in a patient’s QoL. This paper will emphasize the extensive validation studies performed in developing the CLASI, as well as the importance of clinical trials using the CLASI to address the need for improved therapies for patients with lupus skin manifestations.

Immunopathogenesis of skin injury in systemic lupus erythematosus

PURPOSE OF REVIEW

Skin injury is the most common clinical manifestation of SLE and is disfiguring, difficult to treat, and incompletely understood. We provide an overview of recently published articles covering the immunopathogenesis of skin injury in SLE.

RECENT FINDINGS

Skin of SLE has an inherent susceptibility to apoptosis, the cause of which may be multifactorial. Chronic IFN overexpression leads to barrier disruption, infiltration of inflammatory cells, cytokine production, and release of autoantigens and autoantibody production that result in skin injury. Ultraviolet light is the most important CLE trigger and amplifies this process leading to skin inflammation and potentially systemic disease flares.

SUMMARY

The pathogenesis of skin injury in CLE is complex but recent studies highlight the importance of mechanisms driving dysregulated epidermal cell death likely influenced by genetic risk factors, environmental triggers (UV light), and cytotoxic cells and cellular signaling.

Bioinformatic analysis of key biomarkers and immune filtration of skin biopsy in discoid lupus erythematosus

OBJECTIVE

Discoid lupus erythematosus (DLE) is the most common category of chronic cutaneous lupus erythematosus, where the pathological process is proved to be closely associated with immunity. This bioinformatic analysis sought to identify key biomarkers and to perform immune infiltration analysis in the skin biopsy samples of DLE.

METHODS

GSE120809, GSE100093, GSE72535, GSE81071 were used as the data source of gene expression profiles, altogether containing 79 DLE samples and 47 normal controls (NC). Limma package was applied to identify differentially expressed genes (DEGs) and additional Gene Ontology (GO) together with The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were done. Protein-protein interaction network (PPI) was constructed using STRING and Cytoscape. Hub genes were selected by CytoHubba. Finally, immune filtration analysis was finished by the CIBERSORT algorithm, and comparisons between the two groups were accomplished.

RESULTS

A total of 391 DEGs were identified, which were composed of 57 up-regulated genes and 334 down-regulated genes. GO and KEGG enrichment analyses revealed that DEGs were closely related with different steps in the immune response. Top 10 hub genes included GBP2, HLA-F, IFIT2, RSAD2, ISG15, IFIT1, IFIT3, MX1, XAF1 and IFI6. Immune filtration analysis from CIBERSORT had found that compared with NC, DLE samples had higher percentages of CD8+ T cells, T cells CD4 memory activated, T cells gamma delta, macrophages M1 and lower percentages of T cells regulatory, macrophages M2, dendritic cells resting, mast cells resting, mast cells activated.

CONCLUSION

This bioinformatic study selected key biomarkers from the contrast between DLE and NC skin samples and is the first research to analyze immune cell filtration in DLE.

Targeted Biologic Therapy for Systemic Lupus Erythematosus: Emerging Pathways and Drug Pipeline

Following the approval of belimumab, the first drug to be approved for systemic lupus erythematosus (SLE) in over 50 years, advances in our understanding of the pathogenesis of the disease have led to a remarkable number of clinical trials for investigational drugs, each with a unique mechanism of action. These include, but are not limited to, antibodies targeting B or T cells or their interaction, dendritic cells, interferon, and other cytokines. Frustratingly, this boost of studies has not been accompanied by a corresponding success and subsequent approval of novel agents, for reasons only partly attributed to the efficacy of the drugs per se. Successful phase II trials are often followed by failed phase III studies, which typically require many more patients. Nevertheless, recent successes, such as the ustekinumab and baricitinib trials and the positive results from the phase III TULIP-2 study of anifrolumab, provide room for cautious optimism. In this review, we attempt to draw the current landscape of the drug pipeline in SLE, focusing on the rationale behind each drug development, its mechanism of action, and the available preclinical and clinical data. We also highlight lessons learned from failed attempts that have helped to optimize clinical trial design for this challenging disease. We conclude with a look into the future, commenting on the surge of studies in the field of biomarkers and the use of omics technologies in lupus, which aim to pinpoint different disease phenotypes and, ideally, identify subsets of patients with disease that will respond to different biologic drugs.

Systemic lupus erythematosus (SLE): emerging therapeutic targets

INTRODUCTION

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a heterogeneous clinical presentation whose etiologies are multifactorial. A myriad of genetic, hormonal, immunologic, and environmental factors contribute to its pathogenesis, and its diverse biological basis and phenotypic presentations make development of therapeutics difficult. In the past decade, tens of therapeutic targets with hundreds of individual candidate therapeutics have been investigated.

AREAS COVERED

We used a PUBMED database search through April 2020 to review the relevant literature. This review discusses therapeutic targets in the adaptive and innate immune systems, specifically: B cell surface antigens, B cell survival factors, Bruton's tyrosine kinase, costimulators, IL-12/IL-23, the calcineurin pathway, the JAK/STAT pathway, and interferons.

EXPERT OPINION

Our ever-improving understanding of SLE pathophysiology in the past decade has allowed us to identify new therapeutic targets. Multiple new drugs are on the horizon that target different elements of the adaptive and innate immune systems. SLE research remains challenging due to the heterogenous clinical presentation of SLE, confounding from background immunosuppressives being taken by SLE patients, animal models that inadequately recapitulate human disease, and imperfect and complicated outcome measures. Despite these limitations, research is promising and ongoing. The search for new therapies that target specific elements of SLE pathophysiology are discussed as well as key findings, pitfalls, and questions surrounding these targets.

Use of the Cutaneous Lupus Disease Area and Severity Index as an outcome measure in clinical trials: a descriptive study

This study summarizes the use, since its inception, of the Cutaneous Lupus Disease Area and Severity Index (CLASI) as an outcome measure in clinical studies. We systematically searched the MEDLINE, PubMed, EMBASE and Cochrane databases for papers including the term 'cutaneous lupus disease area and severity index' and its abbreviations up to August 2017, identifying 205 abstracts. Following shortlisting, two independent physicians critically reviewed 71 papers for data extraction. We found that a limited number of high-quality studies used the CLASI scoring as an outcome measure. We concluded that further validation is necessary to identify the effectiveness of the CLASI in the assessment of cutaneous lupus erythematosus subtypes. The use of standardized core patient- and physician-reported outcome measures may reduce heterogeneity and allow comparisons between patients enrolled in clinical trials. This would improve the relevance within clinical practice, where the use of CLASI is currently limited.

Oxidative DNA Damage Accelerates Skin Inflammation in Pristane-Induced Lupus Model

Systemic Lupus Erythematosus (SLE) is a chronic inflammatory autoimmune disease in which type I interferons (IFN) play a key role. The IFN response can be triggered when oxidized DNA engages the cytosolic DNA sensing platform cGAS-STING, but the repair mechanisms that modulate this process and govern disease progression are unclear. To gain insight into this biology, we interrogated the role of oxyguanine glycosylase 1 (OGG1), which repairs oxidized guanine 8-Oxo-2'-deoxyguanosine (8-OH-dG), in the pristane-induced mouse model of SLE. Ogg1 ^-/- mice showed increased influx of Ly6C^hi monocytes into the peritoneal cavity and enhanced IFN-driven gene expression in response to short-term exposure to pristane. Loss of Ogg1 was associated with increased auto-antibodies (anti-dsDNA and anti-RNP), higher total IgG, and expression of interferon stimulated genes (ISG) to longer exposure to pristane, accompanied by aggravated skin pathology such as hair loss, thicker epidermis, and increased deposition of IgG in skin lesions. Supporting a role for type I IFNs in this model, skin lesions of Ogg1 ^-/- mice had significantly higher expression of type I IFN genes (Isg15, Irf9, and Ifnb). In keeping with loss of Ogg1 resulting in dysregulated IFN responses, enhanced basal and cGAMP-dependent Ifnb expression was observed in BMDMs from Ogg1 ^-/- mice. Use of the STING inhibitor, H151, reduced both basal and cGAMP-driven increases, indicating that OGG1 regulates Ifnb expression through the cGAS-STING pathway. Finally, in support for a role for OGG1 in the pathology of cutaneous disease, reduced OGG1 expression in monocytes associated with skin involvement in SLE patients and the expression of OGG1 was significantly lower in lesional skin compared with non-lesional skin in patients with Discoid Lupus. Taken together, these data support an important role for OGG1 in protecting against IFN production and SLE skin disease.

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.

The influence of interferon on healthy and diseased skin

Type I interferons (IFNs) are an immunomodulatory class of cytokines that serve to protect against viral and bacterial infection. In addition, mounting evidence suggests IFNs, particularly type I but also IFNγ, are important to the pathogenesis of autoimmune and inflammatory skin diseases, such as cutaneous lupus erythematosus (CLE). Understanding the role of IFNs is relevant to anti-viral responses in the skin, skin biology, and therapeutics for these IFN-related conditions. Type I IFNs (α and β) are produced by recruited inflammatory cells and by the epidermis itself (IFNκ) and have important roles in autoimmune and inflammatory skin disease. Here, we review the current literature utilizing a PubMed database search using terms [interferon/IFN/type I IFN AND lupus/ cutaneous lupus/CLE/dermatomyositis/Sjogrens/psoriasis/lichen planus/morphea/alopecia areata/vitiligo] with a focus on the role of IFNs in basic keratinocyte biology and their implications in the cutaneous autoimmune and inflammatory diseases: cutaneous lupus erythematosus, dermatomyositis, Sjogren's syndrome, psoriasis, lichen planus, alopecia areata and vitiligo. We provide information about genes and proteins induced by IFNs and how downstream mechanisms relate to clinical disease.

Current Insights in Cutaneous Lupus Erythematosus Immunopathogenesis

Cutaneous Lupus Erythematosus (CLE) is a clinically diverse group of autoimmune skin diseases with shared histological features of interface dermatitis and autoantibodies deposited at the dermal-epidermal junction. Various genetic and environmental triggers of CLE promote infiltration of T cells, B cells, neutrophils, antigen presenting cells, and NK cells into lesional skin. In this mini-review, we will discuss the clinical features of CLE, insights into CLE immunopathogenesis, and novel treatment approaches.

Treatment of cutaneous lupus erythematosus: current approaches and future strategies

PURPOSE OF REVIEW

Cutaneous lupus erythematosus (CLE) is a highly heterogeneous autoimmune disease. No specific Federal Drug Administration-approved therapies for CLE-alone are available, and resistance to conventional treatments is common. This review will summarize current treatment approaches and pending treatment strategies.

RECENT FINDINGS

Research into the pathogenesis of CLE is accelerating. A skewed type I interferon production and response contribute to CLE lesions. The pathophysiology of lesions may be similar among the lesional subtypes, and patients with a more TLR9-driven disease mechanism may have more benefit from hydroxychloroquine. Case reports continue to support the use of dapsone for CLE, especially bullous lupus erythematosus. Rituximab and Belimumab have efficacy in patients with systemic lupus erythematosus and severe active CLE. The significant role for type I interferons in CLE and encouraging clinical data suggest anifrolumab as a very promising agent for CLE. Dapirolizumab, BIIB059, Ustekinumab and Janus kinase inhibitors also have supportive early data as promising new strategies for CLE treatment.

SUMMARY

Continued research to understand the mechanisms driving CLE will facilitate the development and approval of new targets. The pipeline for new treatments is rich.

Cutaneous Lupus Erythematosus: Progress and Challenges

PURPOSE OF REVIEW

The review provides an update on the diagnosis, pathogenesis, and treatment of cutaneous lupus erythematosus (CLE).

RECENT FINDINGS

Diagnostic challenges exist in better defining CLE as an independent disease distinct from systemic lupus erythematosus with cutaneous features and further classifying CLE based on clinical, histological, and laboratory features. Recent mechanistic studies revealed more genetic variations, environmental triggers, and immunologic dysfunctions that are associated with CLE. Drug induction specifically has emerged as one of the most important triggers for CLE. Treatment options include topical agents and systemic therapies, including newer biologics such as belimumab, rituximab, ustekinumab, anifrolumab, and BIIB059 that have shown good clinical efficacy in trials. CLE is a group of complex and heterogenous diseases. Future studies are warranted to better define CLE within the spectrum of lupus erythematosus. Better insight into the pathogenesis of CLE could facilitate the design of more targeted therapies.

Helper-like Innate Lymphoid Cells in Humans and Mice

The innate lymphoid cell (ILC) family consists of natural killer (NK) cells, helper-like lymphoid cells (ILC1s, ILC2s, and ILC3s), and lymphoid tissue inducer (LTi) cells. Helper-like ILCs are considered the innate counterpart of T-helper cells because of similarities in their cytokine output and expression of key transcription factors. ILCs provide and regulate innate immune functions before the development of adaptive immunity. They are involved in host defense against pathogens, inflammation, tissue repair, and metabolic homeostasis. However, they can also be involved in inflammatory disorders and carcinogenesis. In this review, we summarize the latest research on ILC development and plasticity in humans and mice, focusing on the pathogenic role of helper-like ILCs in inflammatory disorders, such as asthma, Crohn's disease (CD), and rheumatoid arthritis (RA).

Cutaneous Lupus Erythematosus: Current and Future Pathogenesis-Directed Therapies

Cutaneous lupus erythematosus (CLE) is an autoimmune disease of the skin with significant morbidity. Current treatments are often inadequate to control disease and there are no Food and Drug Administration (FDA)-approved therapies for this potentially debilitating disease, underscoring an unmet medical need. Recent insights into disease pathogenesis have implicated innate and adaptive immune components, including type I and type III interferons in the development of CLE. Promising clinical trials based on these insights are now underway. However, the full spectrum of immune cells, cytokines, and environmental triggers contributing to disease remain to be elucidated. In this review, we will highlight the current understanding of CLE immunopathogenesis, the ongoing clinical trial landscape, and provide a framework for designing future therapeutic strategies for CLE based on new insights into disease pathogenesis.

Robust measurement of clinical improvement in patients with cutaneous lupus erythematosus

Objective

The severity and disease course of cutaneous lupus erythematosus (CLE) are highly variable. Consequently, outcome measures for CLE clinical improvement are heterogeneous, complicating treatment decisions and therapeutic development. This study characterises CLE outcome measures and identifies the influence of clinical improvement thresholds on strengths of associations with patient demographic and clinical factors.

Methods

In this pilot cohort study, multivariable models identified factors associated with CLE activity and skin damage improvement, defined as relative decreases in Cutaneous Lupus Activity and Severity Index (CLASI) activity (CLASI-A) and damage (CLASI-D) scores, over ranges of response thresholds.

Results

66 patients with 119 visit-pairs were included in the CLASI-A analysis. 74 patients with 177 visit-pairs were included in the CLASI-D analysis. Factors associated with CLE activity and damage improvement depended on the response threshold. Some associations were stronger at more stringent thresholds, including subacute CLE predominance with increased likelihood of CLASI-A improvement (R²=0.73; 50% reduction: OR 1.724 (95% CI 0.537 to 5.536); 75%: 5.67 (95% CI 1.56 to 20.5)) and African-American race with decreased likelihood of CLASI-D improvement (R²=0.80; 20%: 0.40 (95% CI 0.17 to 0.93); 40%: 0.25 (95% CI 0.08 to 0.82)). Other associations were stable across multiple thresholds, including older age of CLE development with increased likelihood of CLASI-A improvement (R²=0.25; 50%: 1.05 (95% CI 1.01 to 1.09]; 75%: 1.05 (95% CI 1.00 to 1.10)) and higher initial disease activity with decreased likelihood of CLASI-D improvement (R²=0.55; 20%: 0.91 (95% CI 0.84 to 0.98); 40%: 0.88 (95% CI 0.79 to 0.97)).

Conclusions

Examining a range of CLASI threshold outcomes can comprehensively characterise changes in disease course in patients with CLE. Insufficiently stringent thresholds may fail to distinguish meaningful clinical change from natural fluctuation in disease activity.

Vesiculobullous diseases in relation to lupus erythematosus

Vesiculobullous lesions in lupus erythematosus (LE) are a rare cutaneous manifestation of cutaneous and/or systemic LE with variable presentation. While the minor forms of LE-associated vesiculobullous disease may cause disfigurement and discomfort, the severe forms can present with hyperacute reaction and life-threatening consequences. Specific LE and aspecific cutaneous LE are defined by the presence or absence of interface change on histopathology that can be applied to vesiculobullous diseases in relation to LE. However, the diagnosis of LE-associated vesiculobullous diseases remains difficult, due to the poorly defined nosology and the similarities in clinical and immunohistopathological features among them. Herein, we thoroughly review the topic of vesiculobullous skin disorders that can be encountered in LE patients and organize them into four groups: LE-specific and aspecific vesiculobullous diseases, LE-related autoimmune bullous diseases, and LE in association to non-autoimmune conditions. We sought to provide an updated overview highlighting the pathogenesis, clinical, histological, and immunopathological features, laboratory findings, and treatments and prognosis among vesiculobullous conditions in LE.

IFNγ: signalling, epigenetics and roles in immunity, metabolism, disease and cancer immunotherapy

IFNγ is a cytokine with important roles in tissue homeostasis, immune and inflammatory responses and tumour immunosurveillance. Signalling by the IFNγ receptor activates the Janus kinase (JAK)-signal transducer and activator of transcription 1 (STAT1) pathway to induce the expression of classical interferon-stimulated genes that have key immune effector functions. This Review focuses on recent advances in our understanding of the transcriptional, chromatin-based and metabolic mechanisms that underlie IFNγ-mediated polarization of macrophages to an 'M1-like' state, which is characterized by increased pro-inflammatory activity and macrophage resistance to tolerogenic and anti-inflammatory factors. In addition, I describe the newly discovered effects of IFNγ on other leukocytes, vascular cells, adipose tissue cells, neurons and tumour cells that have important implications for autoimmunity, metabolic diseases, atherosclerosis, neurological diseases and immune checkpoint blockade cancer therapy.

Management of cutaneous manifestations of lupus erythematosus: A systematic review

BACKGROUND

Cutaneous lupus erythematosus (CLE), occurring with or without systemic lupus erythematosus (SLE), is a group of inflammatory skin diseases that can be very debilitating, causing significant psychological distress, and sometimes scarring.

OBJECTIVES

We sought to comprehensively present the evidence for different treatment modalities in patients with cutaneous manifestations of lupus erythematosus (LE).

METHODS

Medline, Embase, Scopus and Cochrane CENTRAL were searched electronically from 1990 to March 2019, using keywords related to cutaneous lupus and synonyms and treatment. Articles retrieved were screened for relevance, including reference lists of retrieved reviews. We included clinical trials, observational studies or case series with ≥5 patients focussing on treatment of CLE, with or without SLE.

RESULTS

The search identified 6637 studies, of which 107 were included. Each study commonly included a heterogeneous mixture of CLE subtypes, with or without SLE. The 107 included studies investigated 11 different categories of treatment in 7343 patients. Treatments included topical calcineurin inhibitors (13 studies), sun protection (5 studies), R-salbutamol cream (2 studies), antimalarials (22 studies), synthetic DMARDs (10 studies), retinoids (2 studies), thalidomide/lenalidomide (22 studies), biologic therapies (15 studies), intravenous immune globulin (3 studies), laser (6 studies) and other therapies (7 studies). General measures to be considered include smoking cessation, sun protection measures and optimisation of vitamin D levels. Moderate evidence exists for benefit with topical CNIs, particularly as a steroid sparing agent in areas at high risk of steroid complications (e.g. facial skin). There is moderate evidence for hydroxychloroquine, which is first-line in SLE patients, limited evidence to support other synthetic DMARDs, and moderate evidence supporting thalidomide but with significant risk of toxicity. Of biologic therapies, there are moderate data to support belimumab. Limited evidence exists for other therapies.

CONCLUSION

Many management options are available for CLE, including topical, systemic and biologic therapies, with a variable balance of efficacy and toxicity. There is a paucity of high-quality clinical trial data. Further trials are required to better understand optimal management of CLE, particularly in specific subgroups.

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).

High levels of circulating interferons type I, type II and type III associate with distinct clinical features of active systemic lupus erythematosus

Background and aim

Interferons (IFNs) are considered to be key molecules in the pathogenesis of systemic lupus erythematosus (SLE). We measured levels of type I, II and III IFNs in a large cohort of patients with systemic lupus erythematosus (SLE) and controls and explored associations among high levels of different IFN types and distinct SLE features.

Methods

Four hundred ninety-seven well-characterized SLE patients and 322 population controls were included. Disease activity was assessed by SLE Disease Activity Index (SLEDAI) and Systemic Lupus Activity Measure (SLAM). Functional type I IFN activity was estimated by a WISH reporter cell assay. Levels of IFN-γ were estimated by MSD 30-plex assay. IFN-α and IFN-λ1 were measured by ELISA. Values above the third quartile of patients’ measurements were defined as high. Associations among high IFN results and SLE features were investigated by nominal regression analysis.

Results

All IFN measurements were higher in SLE patients than in controls. High type I IFN activity correlated with levels of IFN-γ and IFN-α and associated with active SLE in most domains: weight loss, fatigue, fever, rash, lymphadenopathy, arthritis, nephritis and haematological manifestations. Specific SLE subsets were linked to the upregulation of different subtypes of circulating IFNs: high IFN-γ to arthritis, nephritis and anti-Ro60 antibodies and high IFN-α to mucocutaneous engagement and anti-Ro52 and anti-La antibodies. Isolated high IFN-λ1 was coupled to anti-nucleosome antibodies and less severe SLE.

Conclusions

High functional type I IFN activity captures active SLE in most domains, but more distinct patterns of organ involvement are associated with profiles of circulating IFNs. High IFN-γ as well as high functional type I IFN activity is a characteristic of severe SLE with nephritis and arthritis, while elevated levels of IFN-α associate with active mucocutaneous inflammation and a more benign cardiovascular profile. IFN-λ1 in isolation is associated with milder disease. Our findings suggest that IFNs contribute to the heterogeneity of clinical manifestations in SLE, and measuring circulating IFNs could assist in designing clinical trials with therapies targeting IFN pathways.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1878-y) contains supplementary material, which is available to authorized users.

Advancing understanding, diagnosis, and therapies for cutaneous lupus erythematosus within the broader context of systemic lupus erythematosus

Cutaneous lupus erythematosus (CLE) is an autoimmune disease that can be associated with systemic lupus erythematosus (SLE) symptoms. The pathogenesis of both CLE and SLE is multifactorial, involving genetic susceptibility, environmental factors, and innate and adaptive immune responses. Despite the efficacy of current medications, many patients remain refractory, highlighting the necessity for new treatment options. Unfortunately, owing to challenges related in part to trial design and disease heterogeneity, only one new biologic in the last 50 years has been approved by the US Food and Drug Administration for the treatment of SLE. Thus, although SLE and CLE have a similar pathogenesis, patients with CLE who do not meet criteria for SLE cannot benefit from this advancement. This article discusses the recent trials and emphasizes the need to include patients with single-organ lupus, such as CLE, in SLE trials.

Type I and II interferons commit to abnormal expression of chemokine receptor on B cells in patients with systemic lupus erythematosus

Memory B cells are increased in systemic lupus erythematosus (SLE) cases, but the qualitative abnormalities and induction mechanism of these cells are unclear. Here, we subclassified B cells by their chemokine receptor expression and investigated their induction mechanism. The peripheral blood of patients with SLE showed higher levels of CXCR5^- and CXCR3⁺ B cells. CXCR5^-CXCR3⁺ B cell levels were elevated in patients with active SLE, which decreased with improving disease conditions. Interferon (IFN)-γ stimulation increased CXCR3 expression, whereas IFN-β stimulation reduced CXCR5 expression in B cells. Furthermore, CXCR5^-CXCR3⁺ B cells were induced by a combination of IFN-β and IFN-γ stimulation. Renal tissue examination of patients with active lupus nephritis confirmed the presence of CD19⁺CXCR3⁺ B cells. Collectively, the results revealed qualitative abnormalities accompanying reduced CXCR5 expression via type I IFN and enhanced CXCR3 expression via type II IFN in SLE, suggesting their involvement in B cell infiltration into tissues and inflammatory pathogenesis.

Evaluation of the reliability and validity of the Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI) in paediatric cutaneous lupus among paediatric dermatologists and rheumatologists

BACKGROUND

The Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI) is a reliable outcome measure for cutaneous lupus erythematosus (CLE) in adults used in clinical trials. However, it has not been validated in children, limiting clinical trials for paediatric CLE.

OBJECTIVES

This study aimed to validate the CLASI in paediatrics.

METHODS

Eleven paediatric patients with CLE, six dermatologists and six rheumatologists participated. The physicians were trained to use the CLASI and Physician's Global Assessment (PGA), and individually rated all patients using both tools. Each physician reassessed two randomly selected patients. Within each physician group, the intraclass correlation coefficient (ICC) was calculated to assess the reliability of each measure.

RESULTS

CLASI activity scores demonstrated excellent inter- and intrarater reliability (ICC > 0·90), while the PGA activity scores had good inter-rater reliability (ICC 0·73-0·77) among both specialties. PGA activity scores showed excellent (ICC 0·89) and good intrarater reliability (ICC 0·76) for dermatologists and rheumatologists, respectively. Limitations of this study include the small sample size of patients and potential recall bias during the physician rerating session.

CONCLUSIONS

CLASI activity measurement showed excellent inter- and intrarater reliability in paediatric CLE and superiority over the PGA. These results demonstrate that the CLASI is a reliable and valid outcome instrument for paediatric CLE.

Biologics in Chronic Rhinosinusitis: An Update and Thoughts for Future Directions

Background Potential biologic therapies for chronic rhinosinusitis (CRS) is a growing field of interest and research. Biologics target specific immune cells or inflammatory pathways within a disease process, increasing drug efficacy while reducing complications. The success of biologics in other inflammatory conditions such as asthma and atopic dermatitis has spurred much of the corresponding research in CRS. A rapid expansion in the volume of research concerning biologic therapies with potential crossover to treating CRS has made it difficult to stay current. Furthermore, much of the literature has been focused on allergy, asthma, and immunology subspecialties. As the role for biologic therapies in CRS continues to expand, it is increasingly important for otolaryngologists to remain up to date on their progression. Objective The objectives of this review are to provide an update on the growing field of biologics for otolaryngologists who treat CRS and discuss potential future areas of research. Methods A literature review of biologic therapies studied in CRS was performed. In addition, a detailed review of all biologic therapies targeting inflammatory markers involved in Th1-, Th2-, and Th17-mediated inflammation was performed to identify potential areas for future research. The role for biologic therapies in CRS, endotypes of CRS, current biologic therapies studies in CRS, and future areas for research were reviewed. Results Sixty-nine unique biologic therapies have been developed for Th1-, Th2-, and Th17-mediated inflammation. Five biologics are currently being investigated for use in patients with CRS with nasal polyposis. Conclusions As the field of biologics continues to expand, remaining up to date on the current literature may help clinicians identify patients who may benefit from biologic therapies. In addition, ongoing research in other inflammatory disorders with shared pathophysiology to CRS may reveal other potential therapies for CRS that have not previously been investigated.

The 2018 pipeline of targeted therapies under clinical development for Systemic Lupus Erythematosus: a systematic review of trials

Currently, Systemic Lupus Erythematosus (SLE) therapies range from antimalarials to glucocorticoids, in addition to immunosupressive agents or biologics such as rituximab or belimumab, when needed. Several unmet needs remain in the treatment SLE and more targeted drugs with improved safety profiles are expected. Based on recent advances in the understanding of the complex pathogenesis of SLE, several targeted treatments are currently assessed in clinical trials. In this study, we performed a systematic review of all targeted therapies under clinical development in SLE in 17 online registries of clinical trials. The search yielded a total of 1140 trials, from which we identified 74 targeted therapies for SLE. Those treatments target inflammatory cytokines, chemokines, or their receptors (n = 17), B cells or plasma cells (n = 17), intracellular signalling pathways (n = 10), T/B cells costimulation molecules (n = 8), interferons (n = 7), plasmacytoid dendritic cells (pDC) (n = 3), as well as various other targets (n = 12). Not all these candidate drugs will reach phase III, but the broad spectrum of drugs being investigated may satisfy the urgent need for improved lupus medications. The identification of biomarkers that would allow adequate prediction of response-to-therapy remains high, but when solved will allow a more rationale selection of the optimal pharmacological agent at the patient level.

Key genes and functional coexpression modules involved in the pathogenesis of systemic lupus erythematosus

We performed a systematic review of genome-wide gene expression datasets to identify key genes and functional modules involved in the pathogenesis of systemic lupus erythematosus (SLE) at a systems level. Genome-wide gene expression datasets involving SLE patients were searched in Gene Expression Omnibus and ArrayExpress databases. Robust rank aggregation (RRA) analysis was used to integrate those public datasets and identify key genes associated with SLE. The weighted gene coexpression network analysis (WGCNA) was adapted to identify functional modules involved in SLE pathogenesis, and the gene ontology enrichment analysis was utilized to explore their functions. The aberrant expressions of several randomly selected key genes were further validated in SLE patients through quantitative real-time polymerase chain reaction. Fifteen genome-wide gene expression datasets were finally included, which involved a total of 1,778 SLE patients and 408 healthy controls. A large number of significantly upregulated or downregulated genes were identified through RRA analysis, and some of those genes were novel SLE gene signatures and their molecular roles in etiology of SLE remained vague. WGCNA further successfully identified six main functional modules involved in the pathogenesis of SLE. The most important functional module involved in SLE included 182 genes and mainly enriched in biological processes, including defense response to virus, interferon signaling pathway, and cytokine-mediated signaling pathway. This study identifies a number of key genes and functional coexpression modules involved in SLE, which provides deepening insights into the molecular mechanism of SLE at a systems level and also provides some promising therapeutic targets.

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.