Targeting IL-36 in Inflammatory Skin Diseases

Monocytes Expressing IL-36G Play a Crucial Role in Atopic Dermatitis

Atopic dermatitis (ad) is a chronic inflammatory skin disease, with recent studies indicating that immune cells, such as monocytes and inflammatory cytokines, play a crucial role. By retrieving datasets from public databases and analysing immune cell infiltration in lesional skin using CIBERSORT, we found that monocytes and M2 macrophages were significantly upregulated in atopic dermatitis. Differentially expressed gene (DEG) functional enrichment analysis revealed that cytokine-cytokine receptor interaction was the most significantly enriched pathway. Further analysis of cytokines and their receptors, along with their correlation with infiltrating immune cells, identified IL36G-expressing monocytes as a key target in atopic dermatitis. We compared immune cell infiltration and cytokine-related targets in similar inflammatory skin diseases, such as psoriasis and urticaria, to evaluate similarities and differences among these three skin conditions. The analysis revealed that IL36G-expressing monocytes were also highly expressed in psoriasis but did not play a pivotal role in urticaria. Finally, we used molecular docking to predict and validate drugs targeting IL36G. Our study highlights IL36G-expressing monocytes as a common key target in atopic dermatitis and psoriasis, offering novel insights and therapeutic strategies for these related diseases.

Updated genetic background of generalized pustular psoriasis as an autoinflammatory keratinization disease

Generalized pustular psoriasis (GPP) is a severe autoinflammatory keratinization disease (AiKD) characterized by acute flares of widespread sterile pustules and high fever. GPP is potentially life-threatening. Recently clarified genetic predisposing factors for GPP suggest that the excessive activation of innate immune pathways in the skin, including of interleukin (IL)-1 and IL-36 signaling, plays a significant role in the GPP pathogenesis. IL36RN, CARD14, AP1S3, MPO, SERPINA3, BTN3A3, and MEFV have been identified as GPP-related genes. The pathogenesis of GPP provoked by variants in these seven genes is tightly associated with the excessive activation of innate immune pathways and the resulting autoinflammation in the skin. Various biologics, including inhibitors for the tumor necrosis factor, IL-17, and IL-23 pathways, are used as treatments for GPP. The new understanding of the genetic background of GPP, mentioned above, indicates that the genetic predisposing factors are predominantly related to the excessive activation of innate immunity and autoinflammation. In this context, inhibitors of inflammatory signaling, including of the IL-1 and IL-36 pathways, have been used in clinical practice and investigated as potential future therapies.

Advances in Biologic Therapies for Allergic Diseases: Current Trends, Emerging Agents, and Future Perspectives

Biologic therapies have revolutionized the treatment of severe allergic diseases, including asthma, atopic dermatitis (AD), chronic spontaneous urticaria (CSU), chronic rhinosinusitis with nasal polyps (CRSwNP), eosinophilic gastrointestinal diseases (EGIDs), and allergic rhinitis (AR). These molecularly targeted agents provide significant benefits for patients unresponsive to conventional treatments by addressing underlying immune mechanisms, particularly type 2 inflammation driven by cytokines such as IL-4, IL-5, and IL-13. Recent advancements include biologics targeting alarmins like thymic stromal lymphopoietin (TSLP) and IL-33, which may address both type 2 and non-type 2 inflammation, broadening their therapeutic scope. Despite their effectiveness, biologics remain expensive, posing socioeconomic challenges, and there are concerns regarding long-term safety and inter-individual variability in responses. Promising innovations such as bispecific antibodies and ultra-long-acting agents are under investigation, alongside digital health tools like remote biomarker monitoring and AI-driven decision support systems, which aim to enhance personalized care. However, disparities in access, particularly for underserved populations, underscore the need for policy reforms and affordable biosimilars. This review synthesizes recent findings and emerging trends, highlighting the evolving role of biologics in transforming allergic disease management and offering insights into future research directions.

Advances in understanding the role of interleukins in pulmonary fibrosis (Review)

Pulmonary fibrosis (PF) is a progressive, irreversible disease characterized by heterogeneous interstitial lung tissue damage. It originates from persistent or repeated lung epithelial injury and leads to the activation and differentiation of fibroblasts into myofibroblasts. Interleukins (ILs) are a group of lymphokines crucial for immunomodulation that are implicated in the pathogenesis of PF. However, different types of ILs exert disparate effects on PF. In the present review, based on the effect on PF, ILs are classified into three categories: i) Promotors of PF; ii) inhibitors of PF; and iii) those that exert dual effects on PF. Several types of ILs can promote PF by provoking inflammation, initiating proliferation and transdifferentiation of epithelial cells, exacerbating lung injury, while other ILs can inhibit PF through suppressing expression of inflammatory factors, modulating the Th1/Th2 balance and autophagy. The present review summarizes the association of ILs and PF, focusing on the roles and mechanisms of ILs underlying PF.

Current therapeutic overview and future perspectives regarding the treatment of psoriasis

Psoriasis is a chronic inflammatory skin disease affecting millions of people worldwide, characterized by rapid proliferation of keratinocytes, immune cell infiltration, and systemic inflammation. Over time, treatment strategies have evolved significantly from traditional topical therapies and phototherapy to advanced systemic options such as biologics and, more recently, oral small molecule drugs. This review aims to provide an in-depth examination of current psoriasis therapies, with a focus on biologics, oral small molecules, and new and emerging treatments. Several classes of biologic therapies have received regulatory approval for psoriasis, including inhibitors of TNF-α, IL-12/23, IL-17, and IL-23. Biologics have transformed psoriasis care, offering improved disease management and quality of life for patients, with generally favorable safety profiles. However, challenges such as high cost, potential immunogenicity and complexity of administration have sparked interest in alternative treatment options. Oral small molecules, particularly Janus kinase (JAK) inhibitors, have gained attention for their efficacy and ease of use, being orally administered drugs. These drugs mark a shift in therapeutic paradigms by providing an oral option that precisely targets specific signaling pathways. In addition to existing therapies, this review also highlights emerging treatments that could shape the future of psoriasis care, including new small-molecule inhibitors. Early clinical trials suggest that these agents could improve treatment outcomes for psoriasis patients. Current research is increasingly focused on understanding disease recurrence, particularly the influence of tissue-resident memory T cells (TRMs). Avoiding the proliferation of these cells may be crucial in attenuating recurrence. In particular, interleukin-23 (IL-23), produced by CD301b+ cells, has been linked to stimulation of TRM cell proliferation in the skin. This finding highlights that IL-23 inhibitors and treatments targeting CD301b+ cells are promising strategies for maintaining remission and preventing relapse. In summary, the landscape of psoriasis treatments is advancing rapidly, with an increasing focus on personalized, patient-specific therapies. Research is expected to continue to refine and improve therapeutic approaches for this complex disease.

Interleukin 38 reduces antigen-presentation capacity and antibody production after vaccination

The mechanisms that underpin low vaccine responses, which can lead to inadequate protection against infection, are still partially unclear. Interleukin (IL)-38 is a member of the IL-1 family, expressed by B cells among others, that regulates inflammatory responses. A recent study shows that IL-38 suppresses plasma cell generation and antibody production upon immune activation. We hypothesis that IL-38 affects antigen-presentation capacity of innate immune cells, effecting antibody production. Here, we investigated the effect of recombinant human IL-38 on human peripheral blood mononuclear cells and myeloid-derived DCs regarding cytokine production, phagocytosis, and expression of MCH II and co-stimulatory proteins in vitro, and further relate circulating plasma IL-38 concentrations to antibody responses in a cohort of 75 females aged 18-48 vaccinated with BCG and Tdap-IPV. To this end, we found that IL-38 decreased the expression of HLA-DR, HLA-DM, and CD83 on PBMCs, and CD40 and CD86 on MDDCs. IL-38 further impaired phagocytosis capacity of monocytes. Lastly, antibody production against diphtheria toxoids up to eight months post-vaccination was negatively associated with IL-38 plasma concentrations. These data suggest that IL-38 could dampen the effectiveness of antigen-presentation and phagocytosis, and could therefore modulate the immunogenicity of some vaccine types.

Dual blockade of IL-17A and IL-36 pathways via a bispecific antibody exhibits enhanced anti-inflammatory potency

Antibody drugs targeting single inflammatory cytokines have revolutionized the treatment of immune-mediated inflammatory diseases. To investigate whether dual targeting interleukin-17 (IL-17) and IL-36 enhances anti-inflammatory activity, bispecific Ab HB0043 was generated by linking the single chain fragment variables (scFvs) from humanized anti-IL-36R antibody (HB0034) to the C-terminus of the heavy chain of anti-IL-17A IgG1 (HB0017) Fc using a flexible peptide linker. HB0043 largely maintained the binding affinities and biological activities of the two parent monoclonal antibodies (mAbs) in vitro. IL-17 and IL-36 cooperated to amplify the expression of pro-inflammatory and pro-fibrotic genes in normal human dermal fibroblasts (NHDF). However, HB0043 more effectively blocked IL-6 and IL-8 production in NHDF stimulated by IL-17A and IL-36 compared to two monoclonal antibodies. In a mouse model of Oxazolone (OXA)-induced atopic dermatitis and Imiquimod (IMQ)-induced skin inflammation, administration of both anti-IL17A mAb HB0017 and anti-mouse IL-36R surrogate antibody HB0034SA showed improved effectiveness in alleviating skin thickening and inflammation based on histological assessment. Further, in cynomolgus monkeys, HB0043 showed no enhanced target-related toxicity compared with the two parental mAbs in vivo and with a moderate increase in production of anti-drug antibodies. Together, dual blockade of IL-17A and IL-36R in the form of a bispecific antibody may have advantages in blocking the overlapping and non-overlapping functions of these two cytokines in skin inflammation that could not optimally be curtailed with single mAbs. In conclusion, as monotherapy may reach therapeutic celling for certain difficult-to-treat inflammatory and fibrotic diseases, dual targeting could potentially pave a way to combat these diseases.

Therapeutic Advances in Psoriasis: From Biologics to Emerging Oral Small Molecules

Psoriasis is a persistent, inflammatory condition affecting millions globally, marked by excessive keratinocyte proliferation, immune cell infiltration, and widespread inflammation. Over the years, therapeutic approaches have developed significantly, shifting from conventional topical treatments and phototherapy to more sophisticated systemic interventions such as biologics and, recently, oral small-molecule drugs. This review seeks to present a comprehensive investigation of the existing psoriasis treatment options, focusing on biologic agents, oral small molecules, and emerging treatments. Several categories of biologic treatments have received regulatory approval for psoriasis, including TNF-α, IL-17, IL-12/23, and IL-23 inhibitors. Biologics have revolutionized the treatment of psoriasis. These targeted therapies offer significant improvement in disease control and quality of life, with acceptable safety profiles. However, limitations such as cost, potential immunogenicity, and administration challenges have driven the exploration of alternative treatment modalities. Oral small molecules, particularly inhibitors of Janus kinase (JAK), have emerged as options due to their convenience and efficacy. These agents represent a paradigm shift in the management of the condition, offering oral administration and targeted action on specific signaling pathways. In addition to existing therapies, the review explores emerging treatments that hold promise for the future of psoriasis care. These include innovative small-molecule inhibitors. Early-stage clinical trials suggest these agents may enhance outcomes for psoriasis patients. In conclusion, the therapeutic landscape of psoriasis is rapidly evolving, emphasizing targeted, patient-centered treatments. Ongoing research and development are expected to lead to more personalized and effective management strategies for this complex condition.

Evidence on Hidradenitis Suppurativa as an Autoinflammatory Skin Disease

Hidradenitis suppurativa (HS) is a chronic and debilitating inflammatory skin disease that often exhibits heterogeneity in its clinical presentation, especially in the context of its rare syndromic forms. The pathogenesis of HS results from a complex interplay of genetic predisposition, innate and adaptive immunity dysregulation, smoking, obesity and environmental factors. In the early phase of the disease, the innate immune system is hyperactivated, contributing to tissue damage and triggering the activation and amplification of the adaptive immune response, which plays a pivotal role in the chronic stages of the disease. Recent studies focused on elucidating the importance of innate immunity impairment and autoinflammation in HS and increasing evidence has emerged on the occurrence of the disease in the context of well-known monogenic and polygenic autoinflammatory syndromes (AIDs). This review provides a comprehensive examination of the current scientific background supporting the contribution of autoinflammation to HS etiology, including genetic data, molecular studies and clinical evidence, as well as the association between HS and AIDs. However, further research is needed to shed light on the pathogenic mechanism of this challenging condition and to identify potential perspectives for future therapeutic approaches.

Identification of plasma protein markers of allergic disease risk: a mendelian randomization approach to proteomic analysis

BACKGROUND

While numerous allergy-related biomarkers and targeted treatment strategies have been developed and employed, there are still signifcant limitations and challenges in the early diagnosis and targeted treatment for allegic diseases. Our study aims to identify circulating proteins causally associated with allergic disease-related traits through Mendelian randomization (MR)-based analytical framework.

METHODS

Large-scale cis-MR was employed to estimate the effects of thousands of plasma proteins on five main allergic diseases. Additional analyses including MR Steiger analyzing and Bayesian colocalisation, were performed to test the robustness of the associations; These findings were further validated utilizing meta-analytical methods in the replication analysis. Both proteome- and transcriptome-wide association studies approach was applied, and then, a protein-protein interaction was conducted to examine the interplay between the identified proteins and the targets of existing medications.

RESULTS

Eleven plasma proteins were identified with links to atopic asthma (AA), atopic dermatitis (AD), and allergic rhinitis (AR). Subsequently, these proteins were classified into four distinct target groups, with a focus on tier 1 and 2 targets due to their higher potential to become drug targets. MR analysis and extra validation revealed STAT6 and TNFRSF6B to be Tier 1 and IL1RL2 and IL6R to be Tier 2 proteins with the potential for AA treatment. Two Tier 1 proteins, CRAT and TNFRSF6B, and five Tier 2 proteins, ERBB3, IL6R, MMP12, ICAM1, and IL1RL2, were linked to AD, and three Tier 2 proteins, MANF, STAT6, and TNFSF8, to AR.

CONCLUSION

Eleven Tier 1 and 2 protein targets that are promising drug target candidates were identified for AA, AD, and AR, which influence the development of allergic diseases and expose new diagnostic and therapeutic targets.

Spesolimab in the Management of Generalized Pustular Psoriasis With Concurrent Bullous Pemphigoid and Psoriasis

Autoimmune diseases often co-occur due to shared immunological mechanisms, necessitating strategic treatment approaches to manage overlapping conditions without exacerbating each other. A 75-year-old male with a history of psoriasis vulgaris and bullous pemphigoid (BP) developed new-onset pustular psoriasis under systemic corticosteroid therapy, which is known to potentially worsen psoriasis into its pustular form. Histological examination confirmed the diagnosis, showing features typical of pustular psoriasis. The patient was successfully treated with spesolimab, an anti-IL-36 neutralizing antibody, achieving complete remission without aggravating the BP. This case highlights the necessity of cautious treatment selection in patients with multiple autoimmune disorders and underscores the potential role of IL-36 in exacerbating inflammatory responses in BP. Further research into the interaction between IL-36 and BP may provide deeper insights into managing such complex clinical scenarios.

Targeted review of IL36RN mutations in patients with generalised pustular psoriasis

Background

Generalised pustular psoriasis (GPP) is a rare and chronic skin disease historically treated with therapies that were originally intended to treat plaque psoriasis (PsO). However, GPP and plaque PsO have distinct pathogeneses and clinical courses.

Objectives

This study aimed to further characterise the unique genetic background of GPP by summarising evidence on the frequency and type of IL36RN gene mutation, a gene that normally suppresses proinflammatory responses, in patients with GPP compared to patients with GPP and plaque PsO, and patients with plaque PsO only.

Methods and Results

A targeted literature review was conducted to identify studies reporting IL36RN mutations and/or HLA-Cw6 allele frequency in patients with GPP. Meta-analyses showed a significantly higher rate of IL36RN mutations in the GPP-only population compared to the GPP + plaque PsO population (OR 3.51; 95% CI 2.29, 5.38). Monoallelic mutations of IL36RN were found in up to 33.3%, and biallelic mutations in up to 73.2% of patients with GPP (GPP-only and GPP + plaque PsO), in contrast with mono- and biallelic frequencies of only 0%-11.9% and 0%, respectively, in patients with plaque PsO only. Mean age-of-onset ranged from 5.9 to 48.9 years old, with most studies reporting a GPP age-of-onset between 20 and 40 years old. Twenty-one mutations were identified in the biallelic state and three in monoallelic. The most reported mutations were c.115 + 6T > C (p. Arg10ArgfsX1) (18 studies); c.227 C > T (p.Pro76Leu) (10 studies); and c.338 C > T (p.Ser113Leu) (8 studies). Mutations varied depending on geography and ethnicity, with the most frequently reported mutation predominantly reported in East Asian studies and international studies that included Asian patients. Rates of HLA-Cw6, the risk allele most strongly associated with plaque PsO, were 0%-28.6% for patients with GPP, similar to rates in the general population (10.5%-20%).

Conclusion

Considering the differences between GPP and plaque PsO in aetiology and disease symptoms, effective, GPP-specific treatment options are needed, and recent research suggests that blockade of IL-36 signalling may be an effective target for treatment of GPP.

The impact of current investigational drugs for acne on future treatment strategies

INTRODUCTION

Acne vulgaris is one of the most prevalent diseases worldwide with a considerably high cost and a burden on quality of life. There are currently many topical and systemic therapies for acne; however, many are limited by their local adverse event profile. This review provides an update on current, novel Phase I and II trials for acne vulgaris.

AREAS COVERED

This review searched the National Institutes of Health US National Library of Medicine online database of clinical trials (ClinicalTrials.gov) for ongoing Phase I and II trials. Only papers discussing novel therapies were discussed, and combinations of previously FDA-approved drugs were excluded.

EXPERT OPINION

The current investigational approaches to acne treatment reflect an attempt to mitigate the underlying cause of acne pathogenesis. By targeting key mechanisms involved, studies aim to show long-term improvement with less frequent treatment use. This provides potential for more tolerable treatments with better patient adherence, in turn leading to increased efficacy.

Secukinumab in Hidradenitis Suppurativa Patients Who Failed Adalimumab: A 52-Week Real-Life Study

Background

The treatment of hidradenitis suppurativa (HS) has always been a real challenge for dermatologists; to date, adalimumab the only biologic drug approved for HS is adalimumab, an anti-tumor necrosis factor (TNF)-α drug, the approval of this drug dates to 2015, data provided by real life show an effectiveness rate of about 60% percent. Recently (31 October 2023) FDA approves secukinumab for moderate-severe HS. The treatment and management of HS is very challenging as available treatments are very limited and show very variable outcomes.

Methods

We conducted a prospective monocentric study designed to evaluate the efficacy and safety of secukinumab treatment in HS patients in a real-life setting.

Results

The initial cohort of patients recruited included 21 HS patients including 12 females and 9 males. About 57.1% of patients achieved the primary endpoint and recorded significant decrease in all the severity assessment scales (IHS4, DLQI and VAS pain scale) at week 16 and 52, when HiSCR reached 71.4%.

Conclusion

The results of our study highlight that treatment with secukinumab in patients with severe HS who failed adalimumab may be a safe and effective therapeutic weapon.

Spesolimab for the Treatment of Generalized Pustular Psoriasis

Generalized pustular psoriasis (GPP) is a rare but severe skin inflammatory disorder characterized by the eruption of widespread sterile neutrophilic pustules, often accompanied by systemic inflammation. Given its life-threatening potential, GPP requires prompt accurate diagnosis and effective treatment, but its rarity and relapsing-remitting nature pose challenges in performing large-scale randomized controlled clinical trials. Established international guidelines are currently lacking and management guidance often follows that for plaque psoriasis. However, while it can co-exist with plaque psoriasis and has traditionally been classified as a most severe form of psoriasis, GPP is now recognized as a distinct entity, with its own clinicopathological, autoinflammatory, immunologic and genetic features. Research conducted over the past decade revealed that an imbalance of interleukin (IL)-36 signaling favoring the proinflammatory activity is the central driver of the pathogenesis of GPP, thereby laying the groundwork for the development of targeted therapies for the disease. This article reviews the evidence thus far on spesolimab, a selective humanized antibody against the IL-36 receptor that was recently licensed in Europe and the United States for the treatment of GPP flares in adults. In phase II, randomized controlled clinical trials, spesolimab led to rapid and effective skin clearance in patients experiencing a GPP flare and demonstrated superiority to placebo in preventing flares for up to 48 weeks with maintenance treatment, with reassuring safety and tolerability profiles. Spesolimab is considered to be a first-in-class medication establishing itself as the standard of care for the treatment of GPP flares, thus changing the paradigm of the management of GPP to a new era of scientifically- and evidence-based targeted therapy for this distinctive disease.

Spesolimab: a comprehensive review on the anti-IL-36 receptor antibody in dermatology

Interleukin-36 (IL-36) cytokines contribute to the pathogenesis of various inflammatory skin conditions and are potential therapeutic targets. Spesolimab is a monoclonal antibody that inhibits IL-36 signaling recently approved by the Food and Drug Administration for the management of generalized pustular psoriasis flares in adults. Clinical trials are evaluating the efficacy of this monoclonal antibody in a few other dermatological conditions. Here, this review comprehensively summarizes the safety and efficacy of spesolimab treatment in various dermatological conditions.

Knowledge Mapping and Research Hotspots of Generalized Pustular Psoriasis: A Bibliometric Analysis from 2003 to 2023

Background

Generalised pustular psoriasis (GPP) is a chronic inflammatory skin disease. We aimed to visualize the research hotspots and trends of GPP using bibliometric analysis to enhance our comprehension of the future advancements in both basic science and clinical research.

Methods

Relevant publications from July 2003 to July 2023 were obtained from the Web of Science Core Collection on July 12, 2023. The analysis of countries, institutions, authors, references, and keywords associated with this subject was conducted through the utilisation of CiteSpace 6.2.R4, VOSviewer 1.6.18, and Microsoft Excel 2019.

Results

A total of 578 papers were analyzed, authored by 2758 researchers from 191 countries/regions and 1868 institutions, published in 174 academic journals. There was an overall upward trajectory in the volume of annual publications, accompanied by a gradual intensification of research interest in GPP. The United States, UDICE-French Research Universities, and Akiyama M of Nagoya University were the most productive and influential country, institution, and author, respectively. The Journal of Dermatology ranked first with the highest publications, and the Journal of the American Academy of Dermatology received the most citations. High-frequency keywords included "generalized pustular psoriasis", "psoriasis, interleukin-36", "plaque psoriasis", "skin-disease", and "antagonist deficiency". Recent research focuses have included "safety", "secukinumab", "spesolimab", "ap1s3 mutations", and "interleukin-36". Burst detection analysis of keywords showed that "moderate", "ixekizumab treatment", "mutations", "efficacy", and "safety" are current research frontiers in this field.

Conclusion

This bibliometric analysis delineated the landmark publications in GPP that have defined current research hotspots and development trends, notably the applications, efficacy, and safety of biological agents. Future research endeavors are warranted to explore other biological therapeutic options for both acute GPP and the long-term management of chronic GPP.

Pro-inflammatory cytokine IL-6 regulates LMO4 expression in psoriatic keratinocytes via AKT/STAT3 pathway

The transcription factor LIM-only protein 4 (LMO4) is overexpressed in the psoriatic epidermis and regulates keratinocyte proliferation and differentiation. High LMO4 expression levels are induced by interleukin-23 (IL-23) to activate the AKT/STAT3 signaling pathway. Interleukin-6 (IL-6) is mainly involved in regulating T cell functions and development in patients with psoriasis. However, whether LMO4 expression is regulated by IL-6 remains unclear. Therefore, the purpose of this study is to explore the role and molecular mechanisms of IL-6 in regulating LMO4 expression. The interleukin-6 (IL-6) levels in human plasma were determined using a chemiluminescence immunoassay system. A psoriasis-like mouse model was established using imiquimod induction. Epidermal keratinocytes (HaCaT) were cultured in defined keratinocyte-serum-free medium and stimulated by IL-6 alone or with inhibitors. The proteins of interest were detected using western blot analysis, immunofluorescence, and immunohistochemistry. The 5-ethynyl-2'-deoxyuridine assay was used to detect cell proliferation. The results revealed that IL-6 levels were markedly increased in the plasma of patients with psoriasis, compared to healthy control. The high expression of LMO4 was consistent with high levels of IL-6, p-AKT, and p-STAT3 in the lesions of both psoriasis patients and imiquimod-induced psoriasis-like mice. IL-6 activates the AKT/STAT3 signaling pathway, followed by LMO4 high-expression in HaCaT cells. IL-6 induces HaCaT proliferation and differentiation via AKT/STAT3 signaling pathway activation. We think that the high expression of LMO4 in psoriatic keratinocytes requires IL-6 to activate the AKT/STAT3 signaling pathway and leads to epidermal keratinocytes abnormal proliferation and differentiation.

Signaling pathways and targeted therapies for psoriasis

Psoriasis is a common, chronic, and inflammatory skin disease with a high burden on individuals, health systems, and society worldwide. With the immunological pathologies and pathogenesis of psoriasis becoming gradually revealed, the therapeutic approaches for this disease have gained revolutionary progress. Nevertheless, the mechanisms of less common forms of psoriasis remain elusive. Furthermore, severe adverse effects and the recurrence of disease upon treatment cessation should be noted and addressed during the treatment, which, however, has been rarely explored with the integration of preliminary findings. Therefore, it is crucial to have a comprehensive understanding of the mechanisms behind psoriasis pathogenesis, which might offer new insights for research and lead to more substantive progress in therapeutic approaches and expand clinical options for psoriasis treatment. In this review, we looked to briefly introduce the epidemiology, clinical subtypes, pathophysiology, and comorbidities of psoriasis and systematically discuss the signaling pathways involving extracellular cytokines and intracellular transmission, as well as the cross-talk between them. In the discussion, we also paid more attention to the potential metabolic and epigenetic mechanisms of psoriasis and the molecular mechanistic cascades related to its comorbidities. This review also outlined current treatment for psoriasis, especially targeted therapies and novel therapeutic strategies, as well as the potential mechanism of disease recurrence.

Palmoplantar Pustulosis: A Systematic Review of Risk Factors and Therapies

Palmoplantar pustulosis (PPP) is a chronic, relapsing, inflammatory disease that can occur alone or in association with arthritis. There is still controversy about whether it should be separated from psoriasis or classified as pustular psoriasis. Furthermore, drug-induced paradoxical PPP is a special variant of PPP that differs from classic PPP in several ways. Treatment of PPP is still challenging, and there are a number of treatment-resistant cases. This review summarizes the risk factors for the development of PPP and the currently available treatment modalities. Female sex, smokers or ex-smokers, obesity, thyroid dysfunction, and treatment with a tumor necrosis factor (TNF)-α inhibitor have been identified as risk factors for the disease's development, severity, and course. Topical treatments and phototherapy are effective for some patients and are used as a first-line or adjuvant treatment modality. Conventional treatments including retinoids and fumaric acid show good effects and can increase the efficacy of treatment with psoralen + ultraviolet light therapy (PUVA). Ciclosporin is fast acting, but relapse mostly occurs immediately after cessation. TNF-α inhibitors are efficient, and an even better response can be achieved with IL-17 and IL-23 blockers as well as apremilast. The effect of Janus kinase inhibitors seems to be promising according to case reports, but further investigations with larger cohorts are needed.

The emerging role of IL-38 in diseases: A comprehensive review

INTRODUCTION

Interleukin-38 (IL-38) is a new type of anti-inflammatory cytokine, which is mainly expressed in the immunity-related organs and is involved in various diseases including cardiovascular and cerebrovascular diseases, lung diseases, viral infectious diseases and autoimmune diseases.

AIM

This review aims to detail the biological function, receptors and signaling of IL-38, which highlights its therapeutic potential in related diseases.

CONCLUSION

This article provides a comprehensive review of the association between interleukin-38 and related diseases, using interleukin-38 as a keyword and searching the relevant literature through Pubmed and Web of science up to July 2023.

Challenges and Future Trends in Atopic Dermatitis

Atopic dermatitis represents a complex and multidimensional interaction that represents potential fields of preventive and therapeutic management. In addition to the treatment armamentarium available for atopic dermatitis, novel drugs targeting significant molecular pathways in atopic dermatitis biologics and small molecules are also being developed given the condition's complex pathophysiology. While most of the patients are expecting better efficacy and long-term control, the response to these drugs would still depend on numerous factors such as complex genotype, diverse environmental triggers and microbiome-derived signals, and, most importantly, dynamic immune responses. This review article highlights the challenges and the recently developed pharmacological agents in atopic dermatitis based on the molecular pathogenesis of this condition, creating a specific therapeutic approach toward a more personalized medicine.

Hidradenitis Suppurativa and JAK Inhibitors: A Review of the Published Literature

Background: Hidradenitis suppurativa (HS), also known as acne inversa or Verneuil's disease, is a chronic, inflammatory, recurrent, and debilitating skin disease of the hair follicles characterized by inflammatory, painful, deep-rooted lesions in the areas of the body characterized by the presence of the apocrine glands. Unfortunately, huge unmet needs still remain for its treatment. Objective: The purpose of our review was collecting all cases, case series, trials, and ongoing studies available in the literature on the use of this class of drugs for HS. Materials and Methods: The investigated manuscripts included trials, reviews, letters to the editor, real-life studies, case series, and reports. Manuscripts were identified, screened, and extracted for the relevant data following the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. Results: We selected 56 articles of which 25 met the selection criteria for our review. Among the JAK inhibitors to date, there is only one published clinical trial in the literature (Janus kinase 1 inhibitor INCB054707), a real-life study with 15 patients up to week 24 in which upadacitinib was used and a case series where tofacitinib was successfully used. Conversely, there are several ongoing clinical trials. Conclusions: Results to date in the literature show promising levels of efficacy and the safety of JAK inhibitors in HS. Several clinical trials are underway from which it will be very important to compare the available data. There are still too few studies conducted with a low sample size, so it remains critical to investigate this issue further in the future with a real-life study involving a large sample of patients in order to provide safe and viable therapeutic alternatives for HS.