The Role of IL-17 Cytokines in Psoriasis

Discovery and preclinical evaluation of KYS202004A, a novel bispecific fusion protein targeting TNF-α and IL-17A, in autoimmune disease models

The treatment of autoimmune and inflammatory diseases often requires targeting multiple pathogenic pathways. KYS202004A is a novel bispecific fusion protein designed to antagonize TNF-α and IL-17A, pivotal in the pathophysiology of autoimmune and inflammatory diseases. Our initial efforts focused on screening for optimal structure by analyzing expression levels, purity, and binding capabilities. The binding affinity of KYS202004A to TNF-α and IL-17A was evaluated using SPR. In vitro, we assessed the inhibitory capacity of KYS202004A on cytokine-induced CXCL1 expression in HT29 cells. In vivo, its efficacy was tested using a Collagen-Induced Arthritis (CIA) model in transgenic human-IL-17A mice and an imiquimod-induced psoriasis model in cynomolgus monkeys. KYS202004A demonstrated significant inhibition of IL-17A and TNF-α signaling pathways, outperforming the efficacy of monotherapeutic agents ixekizumab and etanercept in reducing CXCL1 expression in vitro and ameliorating disease markers in vivo. In the CIA model, KYS202004A significantly reduced clinical symptoms, joint destruction, and serum IL-6 concentrations. The psoriasis model revealed that KYS202004A, particularly at a 2  mg/kg dose, was as effective as the combination of ixekizumab and etanercept. This discovery represents a significant advancement in treating autoimmune and inflammatory diseases, offering a dual-targeted therapeutic approach with enhanced efficacy over current monotherapies.

Improvement effects of a novel Chinese herbal formula in imiquimod and IL-23-stimulated mouse models of psoriasis

BACKGROUND

Psoriasis is a long-term inflammatory skin disease. A novel herbal formula containing nine Chinese herbal medicines, named Inflammation Skin Disease Formula (ISDF), has been prescribed in clinics for decades.

AIMS

To investigate the efficacy and action mechanisms of ISDF on psoriasis using imiquimod (IMQ) and Interleukin-23 (IL-23)-induced models in mice and reveal the pharmacokinetics profile of ISDF in rats.

METHODS

Topical administration of IMQ and intradermal injection with IL-23 respectively induced skin lesions like psoriasis on the dorsal area of Balb/c and C57 mice. The mice's body weight, skin thickness, and psoriasis area and severity index (PASI) were assessed weekly. SD rats were used in the pharmacokinetics study and the contents of berberine and baicalin were determined.

RESULTS

The PASI scores and epidermal thickness of mice were markedly decreased after ISDF treatment in both models. ISDF treatment significantly decreased the contents of IL-17A and IL-22 in the serum of IMQ- and IL-23-treated mice. Importantly, ISDF markedly downregulated IL-4, IL-6, IL-1β, and tumor necrosis factor α (TNF-α) gene expression, and the phosphorylation of NF-κB p65, JNK, ERKs and MAPK p38 in IMQ-treated mice. The protein phosphorylation of Jak1, Jak2, Tyk2 and Stat3 was significantly mitigated in the ISDF-treated groups. The absorption of baicalin and berberine of ISDF through the gastrointestinal tract of rats was limited, and their distribution and metabolism in rats were also very slow, which suggested ISDF could be used in the long-term application.

CONCLUSIONS

ISDF has a strong anti-psoriatic therapeutic effect on mouse models induced with psoriasis through IMQ and IL-23, which is achieved by inhibiting the activation of the Jak/Stat3-activated IL-23/Th17 axis and the downstream NF-κB signalling and MAPK signalling pathways. ISDF holds great potential to be a therapy for psoriasis and should be further developed for this purpose.

Safety, Tolerability, and Pharmacokinetics of an Oral Small Molecule Inhibitor of IL-17A (LY3509754): A Phase I Randomized Placebo-Controlled Study

For some patients with psoriasis, orally administered small molecule inhibitors of interleukin (IL)-17A may represent a convenient alternative to IL-17A-targeting monoclonal antibodies. This first-in-human study assessed the safety, tolerability, pharmacokinetics (PKs), and peripherally circulating IL-17A target engagement profile of single or multiple oral doses of the small molecule IL-17A inhibitor LY3509754 (NCT04586920). Healthy participants were randomly assigned to receive LY3509754 or placebo in sequential escalating single ascending dose (SAD; dose range 10-2,000 mg) or multiple ascending dose (MAD; dose range 100-1,000 mg daily for 14 days) cohorts. The study enrolled 91 participants (SAD, N = 51 and MAD, N = 40) aged 21-65 years (71% men). LY3509754 had a time to maximum concentration (Tmax) of 1.5-3.5 hours, terminal half-life of 11.4-19.1 hours, and exhibited dose-dependent increases in exposure. LY3509754 had strong target engagement, indicated by elevated plasma IL-17A levels within 12 hours of dosing. Four participants from the 400-mg (n = 1) and 1,000-mg (n = 3) MAD cohorts experienced increased liver transaminases or acute hepatitis (onset ≥ 12 days post-last LY3509754 dose), consistent with drug-induced liver injury (DILI). One case of acute hepatitis was severe, resulted in temporary hospitalization, and was classified as a serious adverse event. No adverse effects on other major organ systems were observed. Liver biopsies from three of the four participants revealed lymphocyte-rich, moderate-to-severe lobular inflammation. We theorize that the DILI relates to an off-target effect rather than IL-17A inhibition. In conclusion, despite strong target engagement and a PK profile that supported once-daily administration, this study showed that oral dosing with LY3509754 was poorly tolerated.

Small-Molecule Inhibitors and Biologics for Palmoplantar Psoriasis and Palmoplantar Pustulosis: A Systematic Review and Network Meta-Analysis

BACKGROUND

The comparative efficacy of biologics and small-molecule inhibitors in treating palmoplantar psoriasis (PP) and palmoplantar pustulosis (PPP) remains uncertain.

OBJECTIVE

The aim was to perform a systematic review and network meta-analysis (NMA) to compare the efficacy of biologics and small-molecule inhibitors for the treatment of PP and PPP.

METHODS

MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were searched for eligible studies from inception to May 13, 2023. This NMA was conducted and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension Statement for Network Meta-Analyses guidelines. Frequentist random-effects models NMA was performed with the surface under the cumulative ranking curve calculated for ranking. Our primary outcome was the proportion of patients achieving a clear/minimal Palmoplantar Psoriasis/Pustulosis Physician Global Assessment score (PPPGA 0/1 or PPPPGA 0/1) response at 12-16 weeks. Secondary outcomes consisted of the percentage of overall improvement in palmoplantar score and of improvement ≥ 75%, at 12-16 weeks.

RESULTS

The study comprised a total of 29 randomized controlled trials (RCTs), involving 4798 psoriasis patients with palmoplantar diseases. For PP, 16 RCTs with nine different treatments, including adalimumab, apremilast, bimekizumab, etanercept, guselkumab, infliximab, ixekizumab, secukinumab, and ustekinumab were included for the analysis. In the NMA of PP, secukinumab 300 mg ranked highest (odds ratio [OR] 33.50, 95% confidence interval [CI] 4.37-256.86) in achieving PPPGA 0/1, followed by guselkumab 100 mg (OR 18.68, 95% CI 10.07-34.65). In the case of PPP, seven RCTs with six treatments, including apremilast, etanercept, guselkumab, imsidolimab, spesolimab, and ustekinumab, were included for the analysis. In the NMA of PPP, although no treatment demonstrated a significant difference compared to placebo in achieving PPPPGA 0/1, guselkumab 100 mg showed the greatest statistically significant improvement in the palmoplantar score (weighted mean difference 31.73, 95% CI 19.89-43.57) as a secondary outcome.

CONCLUSION

Among all available biologics and small-molecule inhibitors, secukinumab 300 mg and guselkumab 100 mg had the most favorable efficacy in treating PP and PPP, respectively.

Pharmacokinetic Profile of Brepocitinib with Topical Administration in Atopic Dermatitis and Psoriasis Populations: Strategy to Inform Clinical Trial Design in Adult and Pediatric Populations

INTRODUCTION

Topical brepocitinib, a tyrosine kinase (TYK)2/Janus kinase (JAK)1 inhibitor, is in development for psoriasis (PsO) and atopic dermatitis (AD). Quantitative analyses of prior clinical trial data were used to inform future clinical trial designs.

METHODS

Two phase 2b studies in patients with AD and PsO were used to characterize the amount of topical brepocitinib and the resultant systemic trough concentration (CTrough) using a linear mixed-effects regression (LMER). This model was used to predict brepocitinib systemic CTrough for higher treated body surface areas (BSAs) in adults and children. Information from non-clinical and clinical trials with oral brepocitinib was leveraged to set safety thresholds. This combined approach was used to inform future dose-strength selection and treated BSA limits.

RESULTS

Data from 256 patients were analyzed. Patient type, dose strength, and frequency had significant impacts on the dose-exposure relationship. Systemic concentration in patients with PsO was predicted to be 45% lower than in patients with AD from the same dose. When topically applied to the same percentage BSA, brepocitinib systemic exposures are expected to be comparable between adults and children. The systemic steady-state exposure after 3% once daily and twice daily (2 mg/cm2) cream applied to less than 50% BSA in patients with AD and PsO, respectively, maintains at least a threefold margin to non-clinical safety findings and clinical hematologic markers.

CONCLUSION

The relationship between the amount of active drug applied and brepocitinib systemic CTrough, described by LMER, may inform the development strategy for dose optimization in the brepocitinib topical program.

Cytoneme-mediated intercellular signaling in keratinocytes essential for epidermal remodeling

The skin, the largest organ, functions as a primary defense mechanism. Epidermal stem cells supply undifferentiated keratinocytes that differentiate as they migrate toward the outermost skin layer. Although such a replenishment process is disrupted in various human skin diseases, its underlying mechanisms remain elusive. With high-resolution live imaging and in vivo manipulations, we revealed that Notch signaling between keratinocytes is mediated by signaling filopodia called cytonemes and is essential for proper keratinocyte differentiation and proliferation. Inhibiting keratinocyte cytonemes reduced Notch expression within undifferentiated keratinocytes, leading to abnormal differentiation and hyperproliferation, resembling human skin disease phenotypes. Overproduction of Interleukin (IL)-17 signal, associated with skin diseases like psoriasis, induces psoriatic phenotypes via cytonemes in zebrafish. Our study suggests that intercellular signaling between keratinocytes through cytonemes is critical for epidermal maintenance, and its misregulation could be an origin of human skin diseases.

Case report of crusted scabies, brief review of its pathophysiology and latest data

Background

Crusted scabies is a rare form of parasitic infection provoked by a massive infestation of the ectoparasite Sarcoptes scabiei varietas hominis on human skin. It is an extremely contagious type of disease and can even lead to a social stigma. In European countries like Greece, many cases remain undiagnosed for long periods, causing extreme distress in the patient's everyday life and social environment.

Case Description

Herein, we present a case of an 86-year-old woman with crusted scabies in Greece, who remained undiagnosed for 5 months. Massive hyperkeratotic plaques on the extremities, and face, palmoplantar keratoderma, and numerous small erythematous papules on the torso with extreme itch were the main clinical manifestations of the patient. Dermoscopy revealed the parasite. All necessary decontamination measures were taken by personnel. Treatment was administered and a complete cure of the disease was observed.

Conclusions

In this case, the use of dermoscopy has attributed to precise crusted scabies diagnosis and acute pharmacological management of the patient. Early diagnosis of such diseases not only saves patients from lethal secondary infections, but also reduces the risk of a massive scabies outbreak. We also conducted a mini-review, analyzing all recent data concerning crusted scabies macroscopic, dermatoscopic, and histological images. All new information concerning the pathophysiological mechanism of crusted scabies manifestation, updated treatment options, and potential resistance to widely-used treatments are provided.

Dynamic Boolean modeling of molecular and cellular interactions in psoriasis predicts drug target candidates

Psoriasis arises from complex interactions between keratinocytes and immune cells, leading to uncontrolled inflammation, immune hyperactivation, and a perturbed keratinocyte life cycle. Despite the availability of drugs for psoriasis management, the disease remains incurable. Treatment response variability calls for new tools and approaches to comprehend the mechanisms underlying disease development. We present a Boolean multiscale population model that captures the dynamics of cell-specific phenotypes in psoriasis, integrating discrete logical formalism and population dynamics simulations. Through simulations and network analysis, the model predictions suggest that targeting neutrophil activation in conjunction with inhibition of either prostaglandin E2 (PGE2) or STAT3 shows promise comparable to interleukin-17 (IL-17) inhibition, one of the most effective treatment options for moderate and severe cases. Our findings underscore the significance of considering complex intercellular interactions and intracellular signaling in psoriasis and highlight the importance of computational approaches in unraveling complex biological systems for drug target identification.

Lithocholic acid derivatives as potent modulators of the nuclear receptor RORγt

Retinoic acid receptor-related orphan receptor γt (RORγt) is a nuclear receptor found in various tissues that plays a crucial role in the differentiation and proliferation of T helper 17 (Th17) cells, as well as in their generation of the pro-inflammatory cytokine IL-17A. RORγt represents a promising therapeutic target for autoimmune diseases, metabolic disorders, and multiple tumors. Despite extensive research efforts focused on the development of small molecule RORγt modulators, no drug candidates have advanced to phase 3 clinical trials owing to a lack of efficacy or safety margin. This outcome highlights the unmet need to optimize small molecule drug candidates targeting RORγt to develop effective therapies for autoimmune and inflammatory diseases. In this study, we synthesized and evaluated 3-oxo-lithocholic acid amidates as a new class of RORγt modulators. Our evaluation entailed biophysical screening, cellular screening in different platforms, molecular docking, and in vitro pharmacokinetic profiling. The top compound from our study (3-oxo-lithocholic acid amidate, A2) binds to RORγt at an equilibrium dissociation constant (KD) of 16.5 ± 1.34 nM based on microscale thermophoresis (MST). Assessment of the efficacy of A2 in the cellular RORγt reporter luciferase assay revealed a half-maximal inhibitory concentration (IC50) value of 225 ± 10.4 nM. Unlike 3-oxo-lithocholic acid, A2 demonstrated the ability to reduce the IL-17A mRNA expression levels in EL4 cells with RORγt expression using quantitative reverse transcriptase PCR (RT-PCR). Validation of the desirable physicochemical properties and stability of A2 sets the stage for the preclinical evaluation of this new class of RORγt modulators in animal models of autoimmune diseases.

IL-17A Orchestrates Reactive Oxygen Species/HIF1α-Mediated Metabolic Reprogramming in Psoriasis

Immune cell-derived IL-17A is one of the key pathogenic cytokines in psoriasis, an immunometabolic disorder. Although IL-17A is an established regulator of cutaneous immune cell biology, its functional and metabolic effects on nonimmune cells of the skin, particularly keratinocytes, have not been comprehensively explored. Using multiomics profiling and systems biology-based approaches, we systematically uncover significant roles for IL-17A in the metabolic reprogramming of human primary keratinocytes (HPKs). High-throughput liquid chromatography-tandem mass spectrometry and nuclear magnetic resonance spectroscopy revealed IL-17A-dependent regulation of multiple HPK proteins and metabolites of carbohydrate and lipid metabolism. Systems-level MitoCore modeling using flux-balance analysis identified IL-17A-mediated increases in HPK glycolysis, glutaminolysis, and lipid uptake, which were validated using biochemical cell-based assays and stable isotope-resolved metabolomics. IL-17A treatment triggered downstream mitochondrial reactive oxygen species and HIF1α expression and resultant HPK proliferation, consistent with the observed elevation of these downstream effectors in the epidermis of patients with psoriasis. Pharmacological inhibition of HIF1α or reactive oxygen species reversed IL-17A-mediated glycolysis, glutaminolysis, lipid uptake, and HPK hyperproliferation. These results identify keratinocytes as important target cells of IL-17A and reveal its involvement in multiple downstream metabolic reprogramming pathways in human skin.

[Pelotherapy and pelotherapy combined with intravenous laser blood irradiation at the sanatorium-resort stage of treatment of patients with psoriasis vulgaris]

Search of new rational ways to increase the effectiveness of treatment and rehabilitation measures for patients with psoriasis vulgaris continues to be one of the urgent problems in modern clinical dermatology.

OBJECTIVE

To carry out a comparative analysis of the impact of different variants of sanatorium-resort treatment (SRT) - pelotherapy and pelotherapy in combination with intravenous laser blood irradiation (ILBI) - on the level of IL-17 and TNF-a, dermatological status, psychoemotional state and quality of life (QL) assessment of patients with psoriasis vulgaris.

MATERIAL AND METHODS

A naturalistic comparative study included 120 patients with psoriasis vulgaris, who were undergoing SRT: 57 patients in the pelotherapy group and 63 in the group of pelotherapy in combination with ILBI. The SRT effectiveness was assessed using the PASI index, the HARS and HDRS scales and the DLQI questionnaire. The dynamics of IL-17 and TNF-a plasma levels in blood plasma was studied. The study duration was 6 months 14 days.

RESULTS

After 14 days of SRT, a decrease in IL-17 and TNF-a levels in blood plasma was statistically significant both in the pelotherapy group and in the group of pelotherapy in combination with ILBI, no statistically significant differences between the groups were found. Furthermore, the comprehensive use of pelotherapy in combination with ILBI has contributed to a more pronounced statistically significant decrease in the PASI index, the HARS and HDRS scales' total scores and an increase in the level of QL. The number of patients with clinical remission was statistically higher in the group of pelotherapy combined with ILBI compared to the pelotherapy group (87.3% versus 42.1%) six months after SRT.

CONCLUSION

The advantage of comprehensive application of pelotherapy and ILBI in comparison with pelotherapy in patients with psoriasis vulgaris in SRT has been shown. The comprehensive application of pelotherapy and ILBI reduces the level of inflammatory biomarkers, improves dermatological and psychoemotional status, improves QL and is well tolerated by patients.

Unraveling Transcriptome Profile, Epigenetic Dynamics, and Morphological Changes in Psoriasis-like Keratinocytes: "Insights into Similarity with Psoriatic Lesional Epidermis"

Keratinocytes are one of the primary cells affected by psoriasis inflammation. Our study aimed to delve deeper into their morphology, transcriptome, and epigenome changes in response to psoriasis-like inflammation. We created a novel cytokine mixture to mimic mild and severe psoriasis-like inflammatory conditions in cultured keratinocytes. Upon induction of inflammation, we observed that the keratinocytes exhibited a mesenchymal-like phenotype, further confirmed by increased VIM mRNA expression and results obtained from confocal microscopy. We performed RNA sequencing to achieve a more global view, revealing 858 and 6987 DEGs in mildly and severely inflamed keratinocytes, respectively. Surprisingly, we found that the transcriptome of mildly inflamed keratinocytes more closely mimicked that of the psoriatic epidermis transcriptome than the severely inflamed keratinocytes. Genes involved in the IL-17 pathway were a major contributor to the similarities of the transcriptomes between mildly inflamed KCs and psoriatic epidermis. Mild and severe inflammation led to the gene regulation of epigenetic modifiers such as HATs, HDACs, DNMTs, and TETs. Immunofluorescence staining revealed distinct 5-hmC patterns in inflamed versus control keratinocytes, and consistently low 5-mC intensity in both groups. However, the global DNA methylation assay detected a tendency of decreased 5-mC levels in inflamed keratinocytes versus controls. This study emphasizes how inflammation severity affects the transcriptomic similarity of keratinocytes to psoriatic epidermis and proves dynamic epigenetic regulation and adaptive morphological changes in inflamed keratinocytes.

Tapinarof cream 1% once daily for the treatment of adults with mild to severe plaque psoriasis: A novel topical therapy targeting the aryl hydrocarbon receptor

Plaque psoriasis is a chronic, immunemediated skin disease characterized by scaly, erythematous, pruritic plaques. The effects of psoriasis are often debilitating and stigmatizing, significantly impacting patients' physical and psychological well-being and quality of life. Current guideline-recommended psoriasis therapies (topicals, oral systemics, and biologics) have substantial limitations that include overall efficacy, safety, tolerability, sites of application, disease severity, and duration and extent of body surface area treated. Due to these limitations, psoriasis treatment regimens often require combination therapy, especially for moderate to severe disease, leading to increased treatment burden. Psoriasis is also associated with increased indirect costs (eg, reduced work productivity), leading to greater total costs expenditures. Thus, more effective, safe, well-tolerated, and cost-effective therapeutic options are needed. Tapinarof cream 1% once daily is a first-in-class, nonsteroidal, topical aryl hydrocarbon receptor agonist approved by the US Food and Drug Administration in 2022 for the treatment of plaque psoriasis in adults. Tapinarof cream has been evaluated in plaque psoriasis, including 2 pivotal phase 3 trials (NCT03956355 and NCT03983980) and a long-term extension trial (NCT04053387). These trials demonstrated high rates of complete skin clearance with tapinarof cream, durable effects while on treatment (a lack of tachyphylaxis for up to 52 weeks), an approximately 4-month remittive effect off therapy after achieving complete clearance and stopping treatment (ie, duration during which psoriasis does not recur off therapy), and no rebound effects after cessation of therapy. According to the US Food and Drug Administration-approved prescribing information, tapinarof may be used to treat plaque psoriasis of any severity and in any location, has no restrictions on duration of use or extent of total body surface area treated, and has no contraindications, warnings, precautions, or drug-drug interactions. Tapinarof cream is thus an efficacious, well-tolerated, steroid-free topical option that addresses many of the limitations of current recommended therapies. Here we review current knowledge on the physical, psychological, and financial burdens of plaque psoriasis and identify how the clinical profile of tapinarof cream can address key treatment gaps important in the management of plaque psoriasis and patient quality of life. In this article, we aim to assist pharmacists and other managed care practitioners by providing an evidence-based overview of tapinarof cream to support patient-centric decision-making.

Tapinarof cream 1% once daily for the treatment of adults with mild to severe plaque psoriasis: A novel topical therapy targeting the aryl hydrocarbon receptor

Plaque psoriasis is a chronic, immunemediated skin disease characterized by scaly, erythematous, pruritic plaques. The effects of psoriasis are often debilitating and stigmatizing, significantly impacting patients' physical and psychological well-being and quality of life. Current guideline-recommended psoriasis therapies (topicals, oral systemics, and biologics) have substantial limitations that include overall efficacy, safety, tolerability, sites of application, disease severity, and duration and extent of body surface area treated. Due to these limitations, psoriasis treatment regimens often require combination therapy, especially for moderate to severe disease, leading to increased treatment burden. Psoriasis is also associated with increased indirect costs (eg, reduced work productivity), leading to greater total costs expenditures. Thus, more effective, safe, well-tolerated, and cost-effective therapeutic options are needed. Tapinarof cream 1% once daily is a first-in-class, nonsteroidal, topical aryl hydrocarbon receptor agonist approved by the US Food and Drug Administration in 2022 for the treatment of plaque psoriasis in adults. Tapinarof cream has been evaluated in plaque psoriasis, including 2 pivotal phase 3 trials (NCT03956355 and NCT03983980) and a long-term extension trial (NCT04053387). These trials demonstrated high rates of complete skin clearance with tapinarof cream, durable effects while on treatment (a lack of tachyphylaxis for up to 52 weeks), an approximately 4-month remittive effect off therapy after achieving complete clearance and stopping treatment (ie, duration during which psoriasis does not recur off therapy), and no rebound effects after cessation of therapy. According to the US Food and Drug Administration-approved prescribing information, tapinarof may be used to treat plaque psoriasis of any severity and in any location, has no restrictions on duration of use or extent of total body surface area treated, and has no contraindications, warnings, precautions, or drug-drug interactions. Tapinarof cream is thus an efficacious, well-tolerated, steroid-free topical option that addresses many of the limitations of current recommended therapies. Here we review current knowledge on the physical, psychological, and financial burdens of plaque psoriasis and identify how the clinical profile of tapinarof cream can address key treatment gaps important in the management of plaque psoriasis and patient quality of life. In this article, we aim to assist pharmacists and other managed care practitioners by providing an evidence-based overview of tapinarof cream to support patient-centric decision-making.

Inflammation and Psoriasis: A Comprehensive Review

Psoriasis is an immune-mediated disease with a strong genetic component that brings many challenges to sick individuals, such as chronic illness, and which has multiple associated comorbidities like cardiovascular disease, metabolic syndrome, inflammatory bowel disease, and psychological disorders. Understanding the interplay between the innate and adaptative immune system has led to the discovery of specific cytokine circuits (Tumor Necrosis Factor-alpha (TNF-α), IL-23, IL-17), which has allowed scientists to discover new biomarkers that can be used as predictors of treatment response and pave the way for personalized treatments. In this review, we describe the footprint psoriasis leaves on the skin and beyond, key pathophysiological mechanisms, current available therapeutic options, and drawbacks faced by existing therapies, and we anticipate potential future perspectives that may improve the quality of life of affected individuals.

A panel of blood-based circulatory miRNAs with diagnostic potential in patients with psoriasis

Psoriasis is a chronic inflammatory skin disease with keratinocyte hyperproliferation and T cells as key mediators of lesional and systemic inflammatory changes. To date, no suitable differential biomarkers are available for the disease diagnosis. More recently, microRNAs have been identified as critical regulators of lesional and systemic immune changes in psoriasis with diagnostic potential. We have performed expression profiling of T cell-specific miRNAs in 38 plasma samples from psoriasis vulgaris patients and an equal number of age- and gender-matched healthy subjects. Our findings have identified a panel of five blood-based circulatory miRNAs with a significant change in their expression levels, comprising miR-215, miR-148a, miR-125b-5p, miR-223, and miR-142-3p, which can differentiate psoriasis vulgaris patients from healthy individuals. The receiver operating characteristic (ROC) curves for all five miRNAs individually and in combination exhibited a significant disease discriminatory area under the curve with an AUC of 0.762 and a p < 0.0001 for all the miRNAs together. Statistically, all five miRNAs in combination depicted the best-fit model in relation to disease severity (PASI) compared with individual miRNAs, with the highest R2 value of 0.94 and the lowest AIC score of 131.8. Each of the miRNAs also exhibited a significant association with at least one of the other miRNAs in the panel. Importantly, the five miRNAs in the panel regulate one or more immune-inflammation pathways based on target prediction, pathway network analysis, and validated roles in the literature. The miRNA panel provides a rationalized combination of biomarkers that can be tested further on an expanded cohort of patients for their diagnostic value.

Real-life experience with ixekizumab in plaque psoriasis: a multi-center, retrospective, 3-year study

BACKGROUND

Confirmatory data on the long-term effectiveness and safety of ixekizumab in psoriatic patients from real-world studies are needed.

OBJECTIVES

The primary aim was to evaluate the 3-year drug survival of ixekizumab in the treatment of patients with moderate-to-severe plaque psoriasis, in a multicenter real-world setting. The secondary aim was to assess the influence of predictive factors on the drug survival of ixekizumab.

METHODS

A retrospective analysis was performed on a cohort of patients with chronic plaque psoriasis, who received at least one dose of ixekizumab before December 2018. The drug survival analysis was performed and descriptively analyzed using Kaplan-Meier survival curves. Multivariable Cox regression analyses were carried out including variables considered to be of clinical importance.

RESULTS

A total of 306 patients were enrolled. The overall drug survival at 12, 24, and 36 months of treatment with ixekizumab was 92.11%, 83.85%, and 80.19%, respectively. A higher probability (HR 2.34) of drug withdrawal was found among patients who had already received an anti-IL-17 agent compared with bio-naive patients (p 0.017).

CONCLUSIONS

We found that ixekizumab is a biological agent characterized by long-term effectiveness, not influenced by several clinical factors and associated with a good safety profile.

A shared tissue transcriptome signature and pathways in psoriasis and ulcerative colitis

Despite multiple efficacious therapies in common between psoriasis (PS) and Ulcerative Colitis (UC), mechanisms underlying their common pathophysiology remain largely unclear. Here we sought to establish a link by evaluating expression differences and pathway alterations in diseased tissues. We identified two sets of differentially expressed genes (DEGs) between lesional and nonlesional tissues in meta-analyses of data collected from baseline samples in 3 UC and then 3 PS available clinical studies from Pfizer. A shared gene signature was defined by 190 DEGs common to both diseases. Commonly dysregulated pathways identified via enrichment analysis include interferon signaling, partly driven by genes IFI6, CXCL9, CXCL10 and CXCL11, which may attract chemotaxis of Th1 cells to inflammatory sites; IL-23 pathway (IL-23A, CCL20, PI3, CXCL1, LCN2); and Th17 pathway except IL-17A. Elevated expression of costimulatory molecules ICOS and CTLA4 suggests ongoing T-cell activation in both diseases. The clinical value of the shared signature is demonstrated by a gene set improvement score reflecting post-treatment molecular improvement for each disease. This is the first study using transcriptomic meta-analysis to define a tissue gene signature and pathways dysregulated in both PS and UC. These findings suggest immune mechanisms may initiate and sustain inflammation similarly in the two diseases.

A Review of the Safety of Interleukin-17A Inhibitor Secukinumab

Secukinumab is an anti-interleukin (IL)-17A IgG1-κ monoclonal antibody approved for psoriasis, psoriatic arthritis, and ankylosing spondylitis. Its efficacy is well documented, but the complete safety profile of secukinumab, especially on long-term use, needs to be studied. IL-17 inhibitors increase the risk of infections, especially respiratory tract infections and candidiasis, and inflammatory bowel disease; the causal relationships are well described. However, evidence regarding the other adverse events is scarce, and causal associations between the adverse events and the biologic remain unresolved. This review aims to present a narrative perspective on the safety of secukinumab and identify some key areas where the safety of secukinumab may potentially be useful in understanding the scope of secukinumab therapy and making informed clinical decisions.

Autophagy: Guardian of Skin Barrier

Autophagy is a major degradation pathway that removes harmful intracellular substances to maintain homeostasis. Various stressors, such as starvation and oxidative stress, upregulate autophagy, and the dysregulation of autophagy is associated with various human diseases, including cancer and skin diseases. The skin is the first defense barrier against external environmental hazards such as invading pathogens, ultraviolet rays, chemical toxins, and heat. Although the skin is exposed to various stressors that can activate autophagy, the roles of autophagy in the skin have not yet been fully elucidated. Accumulating evidence suggests that autophagy is closely associated with pathogenesis and the treatment of immune-related skin diseases. In this study, we review how autophagy interacts with skin cells, including keratinocytes and immune cells, enabling them to successfully perform their protective functions by eliminating pathogens and maintaining skin homeostasis. Furthermore, we discuss the implications of autophagy in immune-related skin diseases, such as alopecia areata, psoriasis, and atopic dermatitis, and suggest that a combination of autophagy modulators with conventional therapies may be a better strategy for the treatment of these diseases.

Oxidative Stress Induced by High Salt Diet—Possible Implications for Development and Clinical Manifestation of Cutaneous Inflammation and Endothelial Dysfunction in Psoriasis vulgaris

Although oxidative stress is recognized as an important effector mechanism of the immune system, uncontrolled formation of reactive oxygen and nitrogen species promotes excessive tissue damage and leads to disease development. In view of this, increased dietary salt intake has been found to damage redox systems in the vessel wall, resulting in endothelial dysfunction associated with NO uncoupling, inflammation, vascular wall remodeling and, eventually, atherosclerosis. Several studies have reported increased systemic oxidative stress accompanied by reduced antioxidant capacity following a high salt diet. In addition, vigorous ionic effects on the immune mechanisms, such as (trans)differentiation of T lymphocytes are emerging, which together with the evidence of NaCl accumulation in certain tissues warrants a re-examination of the data derived from in vitro research, in which the ionic influence was excluded. Psoriasis vulgaris (PV), as a primarily Th17-driven inflammatory skin disease with proven inflammation-induced accumulation of sodium chloride in the skin, merits our interest in the role of oxidative stress in the pathogenesis of PV, as well as in the possible beneficial effects that could be achieved through modulation of dietary salt intake and antioxidant supplementation.

Rosmarinic acid ameliorated psoriatic skin inflammation in mice through the novel inhibition of the interleukin-17A/interleukin-17A receptor interaction

The interaction between interleukin-17A (IL-17A) and IL-17A receptor (IL-17RA) is a crucial target of psoriasis. Several natural compounds from foods or herbs have displayed efficacies on the amelioration of psoriasis. However, the anti-psoriatic mechanisms are mostly through the common anti-inflammatory effects and rarely via the blockage of the IL-17A/IL-17RA interaction. In this study, the IL-17A/IL-17RA-targeting effects of phenylpropanoids, a large class of secondary metabolites in plants, were analyzed. By screening 17 phenylpropanoids, we found that top four compounds with IL-17A/IL-17RA-blocking abilities were rosmarinic acid, eugenol, syringic acid, and gallic acid, with inhibitory concentrations at 50% of 2.14 ± 0.35 mM, 6.35 ± 0.1 mM, 4.79 ± 0.2 mM, and >10 mM, respectively. The oral administration of rosmarinic acid ameliorated redness and scaling on the dorsal skin of imiquimod-induced psoriatic mice in a dose-dependent manner. Rosmarinic acid suppressed the production of IL-23 and IL-17A and the infiltration of granulocyte subsets in skin tissues. Docking analysis showed that rosmarinic acid docked into IL-17A/IL-17RA interaction regions and exhibited hydrogen bonding with Arg-61, Glu-68, Arg-100, and Ser-118 of IL-17A, which are located in the epitope regions recognized by IL-17A neutralizing antibodies Fab6785 and Fab6468. In conclusion, this is the first study reporting that rosmarinic acid is an IL-17A-targeting agent that ameliorates psoriatic skin inflammation in mice via blocking the IL-17A/IL-17RA interaction.

Cytokines and chemokines modulation of itch

Itch (pruritus) is a common cutaneous symptom widely associated with many skin complaints, and chronic itch can be a severe clinical problem. The onset and perpetuation of itch are linked to cytokines, such as interleukin (IL)-31, IL-4, IL-13, IL-33, thymic stromal lymphopoietin, and tumor necrosis factor-alpha, and chemokines, such as chemokine (C-C motif) ligand 2 and C-X-C motif chemokine ligand 10. This review highlights research that has attempted to determine the attributes of various cytokines and chemokines concerning the development and modulation of itch. Through such research, clinical approaches targeting cytokines and/or chemokines may arise, which may further the development of itch therapeutics.