New Frontiers in Psoriatic Disease Research, Part I: Genetics, Environmental Triggers, Immunology, Pathophysiology, and Precision Medicine

Impact of topical and systemic therapy on carotid-intima media thickness in psoriasis

Atherosclerosis, in which chronic inflammation is also effective in it's pathogenesis, is an important cause of morbidity and mortality in psoriasis patients. Early diagnosis and management of atherosclerosis is important. Measurement of carotid intima media thickness is a method used to determine subclinical atherosclerosis. Our aim in this study is to evaluate subclinical atherosclerosis in psoriasis patients and to examine the effects of targeted therapies on atherosclerosis. This study included 105 psoriasis patients who applied to psoriasis outpatient clinic between May 2022 and December 2022. The patients' age, gender, psoriasis area severity index (PASI) and the initiated treatment agent (topical treatment, sekukinumab, iksekizumab, guselkumab, risankizumab) were noted. Carotid intima-media thickness measurements were taken at baseline and after 6 months of treatment. In patients who were treated with secukinumab, ixekizumab, risankizumab, and guselkumab, there was a statistically significant decrease in catorid-intima media thickness at 6th month when compared with the baseline measurements (p = 0,002 p < 0,001 p < 0,001 p = 0,036 p < 0,001). On the other hand, an increase in the thickness was observed in the topical treatment group. According to our study results, targeted systemic treatments contribute to the improvement of subclinical atherosclerosis in psoriasis patients, while this effect was not seen in topical treatments. These results are consistent with literature data reporting that psoriasis is a systemic inflammatory disease.

The role of C-reactive protein and genetic predisposition in the risk of psoriasis: results from a national prospective cohort

BACKGROUND

Psoriasis is an immune-mediated chronic inflammatory disease associated with multiple factors. To evaluate the extent to which C-reactive protein (CRP) and genetic predisposition affect the incidence of psoriasis.

METHODS

The cohort study retrieved 420,040 participants without psoriasis at baseline from the UK Biobank. Serum CRP was categorized into two levels: < 2 mg/L (normal) and ≥ 2 mg/L (elevated). The polygenic risk score (PRS) was used to estimate genetic predisposition, and was characterized as low, moderate and high PRS. The possible interaction and joint associations between CRP and PRS were assessed using Cox proportional hazards models.

RESULTS

Participants with high CRP levels had an increased risk of incident psoriasis compared to those with low CRP levels (HR: 1.26, 95% CI: 1.18-1.34). Participants with high CRP levels and high PRS had the highest risk of incident psoriasis [2.24 (95% CI: 2.01, 2.49)], compared with those had low CRP levels and low PRS. Significant additive and multiplicative interaction were found between CRP and PRS in relation to the incidence of psoriasis.

CONCLUSIONS

Our results suggest that higher CRP concentration may be associated with higher psoriasis incidence, with a more pronounced association observed in individuals with high PRS for psoriasis. So, clinicians should be aware that the risk of incident psoriasis may increase in general population with high CRP levels and high PRS, so that early investigation and intervention can be initiated.

Current treatment of Psoriasis triggered by Cytokine Storm and future immunomodulation strategies

Psoriasis is a chronic condition caused by an inflammation mediated mainly by cytokines and T cells. In COVID-19, the same type of imbalance is common, generating the Cytokine Storm and promoting a worsening in the skin conditions of patients with autoimmune disorders, such as Psoriasis. In this context, one of the main mediators of immune responses presented by SARS-CoV-2 infected patients is the Purinergic System. This immunological resource is capable of stimulating the hyperinflammatory state presented by infected individuals, mainly by the activity of the P2X7 receptor, culminating in the Cytokine Storm and consequently in the Psoriasis crisis. Currently, different drugs are used for patients with Psoriasis, such as immunosuppressants and small molecules; however, the safety of these drugs in infected patients has not been analyzed yet. In this context, studies are being developed to evaluate the possible administration of these traditional drugs to COVID-19 patients with Psoriasis crisis. Along with that, researchers must evaluate the potential of administrating P2X7 antagonists to these patients as well, improving both the systemic and the dermatological prognostics of patients, by reducing the Cytokine Storm and its general effects, but also avoiding the provocation of Psoriasis crisis.

Gasdermin E-mediated keratinocyte pyroptosis participates in the pathogenesis of psoriasis by promoting skin inflammation

BACKGROUND

Psoriasis is a common chronic inflammatory disease with an unclear aetiology. Keratinocytes in psoriasis are susceptible to exogenous triggers that induce inflammatory cell death.

OBJECTIVES

To investigate whether gasdermin E (GSDME)-mediated pyroptosis in keratinocytes contributes to the pathogenesis of psoriasis.

METHODS

Skin samples from patients with psoriasis and from healthy controls were collected to evaluate the expression of GSDME, cleaved caspase-3 and inflammatory factors. We then analysed the data series GSE41662 to further compare the expression of GSDME between lesional and nonlesional skin samples in those with psoriasis. In vivo, a caspase-3 inhibitor and GSDME-deficient mice (Gsdme-/-) were used to block caspase-3/GSDME activation in an imiquimod-induced psoriasis model. Skin inflammation, disease severity and pyroptosis-related proteins were analysed. In vitro, tumour necrosis factor (TNF)-α-induced caspase-3/GSDME-mediated pyroptosis in the HACAT cell line was explored.

RESULTS

Our analysis of the GSE41662 data series found that GSDME was upregulated in psoriasis lesions vs. normal skin. High levels of inflammatory cytokines such as interleukin (IL)-1β, IL-6 and TNF-α were also found in psoriasis lesions. In mice in the Gsdme-/- and caspase-3 inhibitor groups, the severity of skin inflammation was attenuated and GSDME and cleaved caspase-3 levels decreased after imiquimod treatment. Similarly, IL-1β, IL-6 and TNF-α expression was decreased in the Gsdme-/- and caspase-3 inhibitor groups. In vitro, TNF-α induced HACAT cell pyroptosis through caspase-3/GSDME pathway activation, which was suppressed by blocking caspase-3 or silencing Gsdme.

CONCLUSIONS

Our study provides a novel explanation of TNF-α/caspase-3/GSDME-mediated keratinocyte pyroptosis in the initiation and -acceleration of skin inflammation and the progression of psoriasis.

ERAP Inhibitors in Autoimmunity and Immuno-Oncology: Medicinal Chemistry Insights

Endoplasmic reticulum aminopeptidases ERAP1 and 2 are intracellular aminopeptidases that trim antigenic precursors and generate antigens presented by major histocompatibility complex class I (MHC-I) molecules. They thus modulate the antigenic repertoire and drive the adaptive immune response. ERAPs are considered as emerging targets for precision immuno-oncology or for the treatment of autoimmune diseases, in particular MHC-I-opathies. This perspective covers the structural and biological characterization of ERAP, their relevance to these diseases and the ongoing research on small-molecule inhibitors. We describe the chemical and pharmacological space explored by medicinal chemists to exploit the potential of these targets given their localization, biological functions, and family depth. Specific emphasis is put on the binding mode, potency, selectivity, and physchem properties of inhibitors featuring diverse scaffolds. The discussion provides valuable insights for the future development of ERAP inhibitors and analysis of persisting challenges for the translation for clinical applications.

Caffeine Boosts Weight-Lifting Performance in Rats: A Pilot Study

Caffeine is a well-described ergogenic aid used to enhance athletic performance. Using animal models can greatly increase our understanding of caffeine's mechanisms in performance. Here, we adapted an animal weight-lifting exercise model to demonstrate caffeine's ergogenic effect in rats. Male Wistar rats (315 ± 35 g) were randomly divided into two groups: one group received 5 mg·kg-1 of caffeine (0.5 mL; CEx; n = 5) and the other 0.9% NaCl (0.5 mL; PEx; n = 4) through an orogastric probe (gavage) one hour before exercise. Weight-lifting exercise sessions were performed over three subsequent days, and the number of complete squats performed was counted. Analyses of the area under the curve in all three experiments showed that the CEx group responded more to stimuli, performing more squats (1.7-, 2.0-, and 1.6-fold; p < 0.05) than the control group did. These three days' data were analyzed to better understand the cumulative effect of this exercise, and a hyperbolic curve was fitted to these data. Data fitting from the caffeine-supplemented group, CEx, also showed larger Smax and Kd (2.3-fold and 1.6-fold, respectively) than the PEx group did. Our study demonstrated an acute ergogenic effect of caffeine in an animal weight-lifting exercise model for the first time, suggesting potential avenues for future research.

Safety and effectiveness of guselkumab in Japanese patients with psoriasis: 20-week interim analysis of a postmarketing surveillance study

A 52-week postmarketing surveillance study was initiated to evaluate the safety and effectiveness of guselkumab, a human anti-interleukin 23 subunit p19 monoclonal antibody, in Japanese patients with psoriasis vulgaris, psoriatic arthritis, generalized pustular psoriasis, and erythrodermic psoriasis in real-world practice. Here, we report results of the 20-week interim analysis of the ongoing postmarketing surveillance study. Patients who received guselkumab between May 2018 (the date of commercial launch in Japan) and October 2020 were registered in this study. In total, 411 and 245 patients were included in the safety and effectiveness analysis sets, respectively. Adverse drug reactions (ADRs) occurred in 6.6% (27 of 411) and serious ADRs in 2.2% (nine of 411) of patients. The most frequent ADRs by System Organ Class were "Infections and infestations" (2.4%), with nasopharyngitis being the most frequently observed ADR (0.7%). The mean Psoriasis Area Severity Index score decreased from 11.6 at baseline to 6.5 at week 4 and 2.2 at week 20, with improvements achieving statistical significance at each time point. Clinical Global Impression, Dermatology Life Quality Index, and Nail Psoriasis Severity Index outcomesalso showed substantial improvements. Our findings demonstrate that guselkumab is well tolerated and effective in Japanese patients with psoriasis through 20 weeks of treatment in real-world clinical practice, showing significant effectiveness observed as early as 4 weeks. The study was officially registered with the University Hospital Medical Information Network Clinical Trials Registry with the identifier UMIN000032969.

Psoriasis and Psoriatic Arthritis-Associated Genes, Cytokines, and Human Leukocyte Antigens

In recent years, research has intensified in exploring the genetic basis of psoriasis (PsO) and psoriatic arthritis (PsA). Genome-wide association studies (GWASs), including tools like ImmunoChip, have significantly deepened our understanding of disease mechanisms by pinpointing risk-associated genetic loci. These efforts have elucidated biological pathways involved in PsO pathogenesis, particularly those related to the innate immune system, antigen presentation, and adaptive immune responses. Specific genetic loci, such as TRAF3IP2, REL, and FBXL19, have been identified as having a significant impact on disease development. Interestingly, different genetic variants at the same locus can predispose individuals to either PsO or PsA (e.g., IL23R and deletion of LCE3B and LCE3C), with some variants being uniquely linked to PsA (like HLA B27 on chromosome 6). This article aims to summarize known and new data on the genetics of PsO and PsA, their associated genes, and the involvement of the HLA system and cytokines.

Rare coding variants in NOX4 link high ROS levels to psoriatic arthritis mutilans

Psoriatic arthritis mutilans (PAM) is the rarest and most severe form of psoriatic arthritis, characterized by erosions of the small joints and osteolysis leading to joint disruption. Despite its severity, the underlying mechanisms are unknown, and no susceptibility genes have hitherto been identified. We aimed to investigate the genetic basis of PAM by performing massive parallel sequencing in sixty-one patients from the PAM Nordic cohort. We found rare variants in the NADPH oxidase 4 (NOX4) in four patients. In silico predictions show that the identified variants are potentially damaging. NOXs are the only enzymes producing reactive oxygen species (ROS). NOX4 is specifically involved in the differentiation of osteoclasts, the cells implicated in bone resorption. Functional follow-up studies using cell culture, zebrafish models, and measurement of ROS in patients uncovered that these NOX4 variants increase ROS levels both in vitro and in vivo. We propose NOX4 as the first candidate susceptibility gene for PAM. Our study links high levels of ROS caused by NOX4 variants to the development of PAM, offering a potential therapeutic target.

Systemic pharmacological treatments for chronic plaque psoriasis: a network meta-analysis

BACKGROUND

Psoriasis is an immune-mediated disease with either skin or joints manifestations, or both, and it has a major impact on quality of life. Although there is currently no cure for psoriasis, various treatment strategies allow sustained control of disease signs and symptoms. The relative benefit of these treatments remains unclear due to the limited number of trials comparing them directly head-to-head, which is why we chose to conduct a network meta-analysis.

OBJECTIVES

To compare the benefits and harms of non-biological systemic agents, small molecules, and biologics for people with moderate-to-severe psoriasis using a network meta-analysis, and to provide a ranking of these treatments according to their benefits and harms.

SEARCH METHODS

For this update of the living systematic review, we updated our searches of the following databases monthly to October 2022: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of systemic treatments in adults over 18 years with moderate-to-severe plaque psoriasis, at any stage of treatment, compared to placebo or another active agent. The primary outcomes were: proportion of participants who achieved clear or almost clear skin, that is, at least Psoriasis Area and Severity Index (PASI) 90; proportion of participants with serious adverse events (SAEs) at induction phase (8 to 24 weeks after randomisation).

DATA COLLECTION AND ANALYSIS

We conducted duplicate study selection, data extraction, risk of bias assessment, and analyses. We synthesised data using pairwise and network meta-analysis (NMA) to compare treatments and rank them according to effectiveness (PASI 90 score) and acceptability (inverse of SAEs). We assessed the certainty of NMA evidence for the two primary outcomes and all comparisons using CINeMA, as very low, low, moderate, or high. We contacted study authors when data were unclear or missing. We used the surface under the cumulative ranking curve (SUCRA) to infer treatment hierarchy, from 0% (worst for effectiveness or safety) to 100% (best for effectiveness or safety).

MAIN RESULTS

This update includes an additional 12 studies, taking the total number of included studies to 179, and randomised participants to 62,339, 67.1% men, mainly recruited from hospitals. Average age was 44.6 years, mean PASI score at baseline was 20.4 (range: 9.5 to 39). Most studies were placebo-controlled (56%). We assessed a total of 20 treatments. Most (152) trials were multicentric (two to 231 centres). One-third of the studies (65/179) had high risk of bias, 24 unclear risk, and most (90) low risk. Most studies (138/179) declared funding by a pharmaceutical company, and 24 studies did not report a funding source. Network meta-analysis at class level showed that all interventions (non-biological systemic agents, small molecules, and biological treatments) showed a higher proportion of patients reaching PASI 90 than placebo. Anti-IL17 treatment showed a higher proportion of patients reaching PASI 90 compared to all the interventions. Biologic treatments anti-IL17, anti-IL12/23, anti-IL23, and anti-TNF alpha showed a higher proportion of patients reaching PASI 90 than the non-biological systemic agents. For reaching PASI 90, the most effective drugs when compared to placebo were (SUCRA rank order, all high-certainty evidence): infliximab (risk ratio (RR) 49.16, 95% CI 20.49 to 117.95), bimekizumab (RR 27.86, 95% CI 23.56 to 32.94), ixekizumab (RR 27.35, 95% CI 23.15 to 32.29), risankizumab (RR 26.16, 95% CI 22.03 to 31.07). Clinical effectiveness of these drugs was similar when compared against each other. Bimekizumab and ixekizumab were significantly more likely to reach PASI 90 than secukinumab. Bimekizumab, ixekizumab, and risankizumab were significantly more likely to reach PASI 90 than brodalumab and guselkumab. Infliximab, anti-IL17 drugs (bimekizumab, ixekizumab, secukinumab, and brodalumab), and anti-IL23 drugs except tildrakizumab were significantly more likely to reach PASI 90 than ustekinumab, three anti-TNF alpha agents, and deucravacitinib. Ustekinumab was superior to certolizumab. Adalimumab, tildrakizumab, and ustekinumab were superior to etanercept. No significant difference was shown between apremilast and two non-biological drugs: ciclosporin and methotrexate. We found no significant difference between any of the interventions and the placebo for the risk of SAEs. The risk of SAEs was significantly lower for participants on methotrexate compared with most of the interventions. Nevertheless, the SAE analyses were based on a very low number of events with very low- to moderate-certainty evidence for all the comparisons. The findings therefore have to be viewed with caution. For other efficacy outcomes (PASI 75 and Physician Global Assessment (PGA) 0/1), the results were similar to the results for PASI 90. Information on quality of life was often poorly reported and was absent for several of the interventions.

AUTHORS' CONCLUSIONS

Our review shows that, compared to placebo, the biologics infliximab, bimekizumab, ixekizumab, and risankizumab were the most effective treatments for achieving PASI 90 in people with moderate-to-severe psoriasis on the basis of high-certainty evidence. This NMA evidence is limited to induction therapy (outcomes measured from 8 to 24 weeks after randomisation), and is not sufficient for evaluating longer-term outcomes in this chronic disease. Moreover, we found low numbers of studies for some of the interventions, and the young age (mean 44.6 years) and high level of disease severity (PASI 20.4 at baseline) may not be typical of patients seen in daily clinical practice. We found no significant difference in the assessed interventions and placebo in terms of SAEs, and the safety evidence for most interventions was very low to moderate quality. More randomised trials directly comparing active agents are needed, and these should include systematic subgroup analyses (sex, age, ethnicity, comorbidities, psoriatic arthritis). To provide long-term information on the safety of treatments included in this review, an evaluation of non-randomised studies is needed. Editorial note: This is a living systematic review. Living systematic reviews offer a new approach to review updating, in which the review is continually updated, incorporating relevant new evidence as it becomes available. Please refer to the Cochrane Database of Systematic Reviews for the current status of this review.

Safety of guselkumab treatment for up to 5 years in patients with moderate-to-severe psoriasis: pooled analyses across seven clinical trials with more than 8600 patient-years of exposure

BACKGROUND

Guselkumab has demonstrated favourable safety and efficacy across individual clinical studies in adults with moderate-to-severe plaque psoriasis.

OBJECTIVES

To evaluate the safety of guselkumab in patients with psoriasis using pooled data from seven phase II/III studies (X-PLORE, VOYAGE 1, VOYAGE 2, NAVIGATE, ORION, ECLIPSE, Japan registration).

METHODS

All studies, except NAVIGATE and ECLIPSE (active comparator-controlled only), included a 16-week placebo-controlled period; X-PLORE, VOYAGE 1 and VOYAGE 2 included both placebo and active controls. In most studies, guselkumab-treated patients received 100-mg subcutaneous injections at week 0, week 4, and then every 8 weeks thereafter. Safety data were summarized for the placebo-controlled period (weeks 0-16) and through the end of the reporting period (up to 5 years). Incidence rates of key safety events were integrated post hoc, adjusted for the duration of follow-up and reported per 100 patient-years (PY).

RESULTS

During the placebo-controlled period, 544 patients received placebo (165 PY) and 1220 received guselkumab (378 PY). Through the end of the reporting period, 2891 guselkumab-treated patients contributed 8662 PY of follow-up. During the placebo-controlled period, in the guselkumab and placebo groups, respectively, rates of adverse events (AEs) were 346/100 PY and 341/100 PY, and infections were 95.9/100 PY and 83.6/100 PY. Rates of serious AEs (6.3/100 PY vs. 6.7/100 PY), AEs leading to discontinuation (5.0/100 PY vs. 9.7/100 PY), serious infections (1.1/100 PY vs. 1.2/100 PY), malignancy (0.5 patients/100 PY vs. 0.0 patients/100 PY) and major adverse cardiovascular events (MACE; 0.3/100 PY vs. 0.0/100 PY) were low and comparable between guselkumab and placebo. Through the end of the reporting period, safety event rates were lower than or comparable to the placebo-controlled period in guselkumab-treated patients: AEs, 169/100 PY; infections, 65.9/100 PY; serious AEs, 5.3/100 PY; AEs leading to discontinuation, 1.6/100 PY; serious infections, 0.9/100 PY; malignancy, 0.7/100 PY; and MACE, 0.3/100 PY. There were no cases of Crohn disease, ulcerative colitis, opportunistic infection or active tuberculosis related to guselkumab.

CONCLUSIONS

In this comprehensive analysis of 2891 guselkumab-treated patients with psoriasis followed for up to 5 years (8662 PY), guselkumab demonstrated favourable safety, consistent with previous reports. Safety event rates in guselkumab-treated patients were similar to those observed with placebo and were consistent throughout long-term treatment.

Cell-Specific and Variant-Linked Alterations in Expression of ERAP1, ERAP2, and LNPEP Aminopeptidases in Psoriasis

ERAP1, ERAP2, and LNPEP are aminopeptidases implicated in autoimmune pathophysiology. In this study, we show that ERAP2 is upregulated and ERAP1 is downregulated in patients with psoriasis who are homozygous for autoimmune-linked variants of ERAP. We also demonstrate that aminopeptidase expression is not uniform in the skin. Specifically, the intracellular antigen-processing aminopeptidases ERAP1 and ERAP2 are strongly expressed in basal and early spinous layer keratinocytes, whereas granular layer keratinocytes expressed predominantly LNPEP, an aminopeptidase specialized in the processing of extracellular antigens for presentation to T cells. In psoriasis, basal keratinocytes also expressed the T-cell- and monocyte-attracting chemokine, CCL2, and the T-cell-supporting cytokine, IL-15. In contrast, TGF-β1 was the major cytokine expressed by healthy control basal keratinocytes. SFRP2-high dermal fibroblasts were also noted to have an ERAP2-high expression phenotype and elevated HLA-C. In psoriasis, the SFRP2-high fibroblast subpopulation also expressed elevated CXCL14. From these results, we postulate that (i) an increased ERAP2/ERAP1 ratio results in altered antigen processing, a potential mechanism by which ERAP risk alleles predispose individuals to autoimmunity; (ii) ERAP2-high expressing cells display a unique major histocompatibility complex-bound peptidome generated from intracellular antigens; and (iii) the granular layer peptidome is skewed toward extracellular antigens.

Implications of interleukin-17 in psoriatic lesions as Koebner phenomenon caused by recurrent occupational burns

The Koebner phenomenon (KP) is the emergence of new lesions in an uninvolved skin area caused by different types of stimulations, including mechanical stress, chemical stress, trauma, or injury. KP affects patients with certain skin diseases and is frequently observed in patients with psoriasis. We report the case of a 43-year-old obese male welder who developed psoriatic lesions only in areas of repeated burns due to his occupation. He was repeatedly exposed to mild burns in his anterior neck and the periorbital region as he was welding without shield protection. Subsequently, erythema appeared in the same region. Skin appearance and skin biopsy suggested psoriasis vulgaris (PV), and immunohistochemical analysis of anti-interleukin (IL)-17, a crucial element in the development of PV, showed the positivestained cells. The anti-IL-17 staining was prominent around the thickened epidermis as psoriatic lesions. IL-17 produced by T helper 17 cells stimulates keratinized cells and promotes chemokine secretion involved in neutrophil migration. Our case showed that patients, even without a history of PV, may have a risk of developing KP and PV via the enhanced production of IL- 17 locally in the repeated burn area. No recurrence of skin symptoms was observed when the patient used a fully defensive shield during welding.

Proteomic and Metabolomic Changes in Psoriasis Preclinical and Clinical Aspects

Skin diseases such as psoriasis (Ps) and psoriatic arthritis (PsA) are immune-mediated inflammatory diseases. Overlap of autoinflammatory and autoimmune conditions hinders diagnoses and identifying personalized patient treatments due to different psoriasis subtypes and the lack of verified biomarkers. Recently, proteomics and metabolomics have been intensively investigated in a broad range of skin diseases with the main purpose of identifying proteins and small molecules involved in the pathogenesis and development of the disease. This review discusses proteomics and metabolomics strategies and their utility in research and clinical practice in psoriasis and psoriasis arthritis. We summarize the studies, from in vivo models conducted on animals through academic research to clinical trials, and highlight their contribution to the discovery of biomarkers and targets for biological drugs.

Pharmacogenomics on the Treatment Response in Patients with Psoriasis: An Updated Review

The efficacy and the safety of psoriasis medications have been proved in trials, but unideal responses and side effects are noted in clinical practice. Genetic predisposition is known to contribute to the pathogenesis of psoriasis. Hence, pharmacogenomics gives the hint of predictive treatment response individually. This review highlights the current pharmacogenetic and pharmacogenomic studies of medical therapy in psoriasis. HLA-Cw*06 status remains the most promising predictive treatment response in certain drugs. Numerous genetic variants (such as ABC transporter, DNMT3b, MTHFR, ANKLE1, IL-12B, IL-23R, MALT1, CDKAL1, IL17RA, IL1B, LY96, TLR2, etc.) are also found to be associated with treatment response for methotrexate, cyclosporin, acitretin, anti-TNF, anti-IL-12/23, anti-IL-17, anti-PDE4 agents, and topical therapy. Due to the high throughput sequencing technologies and the dramatic increase in sequencing cost, pharmacogenomic tests prior to treatment by whole exome sequencing or whole genome sequencing may be applied in clinical in the future. Further investigations are necessary to manifest potential genetic markers for psoriasis treatments.

Living with Psoriasis Vulgaris and Multi-Treatment Failure: A Patient and Dermatologist Perspective

Psoriasis vulgaris is a systemic, chronic inflammatory disease affecting 2-3% of the population. Recent advances in the understanding of the pathophysiology of psoriatic disease have facilitated the development of novel therapeutic options with improved safety and efficacy. This article is coauthored by a patient with a lifelong history of psoriasis who experienced multiple treatment failures. He details his diagnosis and treatment experiences, as well as the physical, mental, and social ramifications of his skin condition. He then goes on to elaborate how evolutions in the treatment of psoriatic disease have impacted his life. This case is then discussed from the perspective of a dermatologist specializing in inflammatory skin disorders. We highlight the clinical features of psoriasis, its medical and psychosocial comorbidities, and the current landscape of psoriatic disease treatments.

Mendelian Randomization Studies in Psoriasis and Psoriatic Arthritis: A Systematic Review

Psoriasis (PSO) and psoriatic arthritis (PSA) are inflammatory diseases with complex genetic and environmental contributions. Although studies have identified environmental and clinical associations with PSO/PSA, causality is difficult to establish. Mendelian randomization (MR) employs the random assortment of genetic alleles at birth to evaluate the causal impact of exposures. We systematically reviewed 27 MR studies in PSO/PSA examining health behaviors, comorbidities, and biomarkers. Exposures, including smoking, obesity, cardiovascular disease, and Crohn's disease, were causal for PSO and PSA, whereas PSO was causally associated with several comorbidities. These findings provide insights that can guide preventive counseling and precision medicine.

An innovative framework to determine the implementation level of personalized medicine: A systematic review

Background

Personalized medicine (PM) is now the new frontier in patient care. The application of this new paradigm extends to various pathologies and different patient care phases, such as diagnosis and treatment. Translating biotechnological advances to clinical routine means adapting health services at all levels is necessary.

Purpose

This article aims to identify the elements for devising a framework that will allow the level of PM implementation in the country under study to be quantitatively and qualitatively assessed and that can be used as a guideline for future implementation plans.

Methods

A systematic review was conducted per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The research question was: What are the domains for determining the level of implementation of PM at the national level? The domains for assessing the degree of PM implementation, which would form the framework, were established.

Results

19 full-text studies that met the inclusion criteria were peer-selected in the systematic review. From all the studies that were included, 37 elements-encompassed in 11 domains-were extracted for determining the degree of PM implementation. These domains and their constituent elements comprise the qualitative and quantitative assessment framework presented herein. Each of the elements can be assessed individually. On the other hand, the domains were standardized to all have the same weight in an overall assessment.

Conclusions

A framework has been developed that takes a multi-factorial approach to determine the degree of implementation of PM at the national level. This framework could also be used to rank countries and their implementation strategies according to the score they receive in the application of the latter. It could also be used as a guide for developing future national PM implementation strategies.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022338611, Identifier: CRD42022338611.

Functional Interplay between IL-9 and Peptide YY Contributes to Chronic Skin Inflammation

Complex interactions between keratinocytes and various cell types, such as inflammatory cells and stromal cells, contribute to the pathogenesis of chronic inflammatory skin lesions. In proinflammatory cytokine‒mediated disease settings, IL-9 plays a pathological role in inflammatory dermatitis. However, IL-9‒related mechanisms remain incompletely understood. In this study, we established tamoxifen-induced keratinocyte-specific IL-9RA-deficient mice (K14^CRE/ERTIl9ra^Δ/Δ mice) to examine the role of IL-9 in multicellular interactions under chronic skin inflammatory conditions. Studies using an imiquimod-induced psoriasis-like model showed that K14^CRE/ERTIl9ra^Δ/Δ mice exhibited a significantly reduced severity of dermatitis and mast cell infiltration compared with control K14^WTIl9ra^fl/fl mice. Transcriptome analyses of psoriasis-like lesions showed that the level of peptide Y-Y (Pyy), a member of the neuropeptide Y family, was markedly downregulated in K14^CRE/ERTIl9ra^Δ/Δ epidermis. Pyy blockade suppressed epidermal thickening and mast cell numbers in imiquimod-treated wild-type mice. Together with in vitro studies indicating that Pyy induced IL-9 production and chemotactic activity in bone marrow‒derived mast cells, these findings suggest that Pyy-mediated interplay between keratinocytes and mast cells contributes to psoriasiform inflammation. Further investigation focusing on the IL-9‒Pyy axis may provide valuable information for the development of new treatment modalities for inflammatory dermatitis.

Prevention and risk assessment of cardiovascular events in a population of patients with psoriasis and psoriatic arthritis

Psoriasis is a chronic, inflammatory, often relapsing disease that is frequently associated with other diseases of similar pathogenesis. The multi-morbidity in the psoriasis population significantly impedes both diagnosis and implementation of appropriate preventive measures. However, the common denominator for this group of diseases is the inflammatory process that initiates the appearance of subsequent symptoms and health consequences, most of which can be avoided or alleviated by modifying the patient’s lifestyle and incorporating appropriate treatment. Health consequences associated with systemic inflammation include cardiovascular incidents and other cardiometabolic diseases.

This article was based on available publications on the onset, incidence, and prevention of cardiovascular disease in the psoriasis patient population.

Roles of Infection in Psoriasis

Psoriasis is a chronic, immune-mediated disorder with cutaneous and systemic manifestations. Genetic predisposition, environmental factors, and immune dysfunction all contribute to the pathogenesis of psoriasis with host-microbe interaction governing the progression of this disease. Emerging evidence has indicated that infection is an environmental trigger for psoriasis and plays multiple roles in its maintenance as evidenced by the frequent association between guttate psoriasis onset and acute streptococcal infection. Different infectious factors act on immune cells to produce inflammatory cytokines that can induce or aggravate psoriasis. In addition to bacterial infections, viral and fungal infections have also been shown to be strongly associated with the onset or exacerbation of psoriasis. Intervention of skin microbiota to treat psoriasis has become a hot research topic. In this review, we summarize the effects of different infectious factors (bacteria, viruses, and fungi) on psoriasis, thereby providing insights into the manipulation of pathogens to allow for the identification of improved therapeutic options for the treatment of this condition.

Climatotherapy at the Dead Sea for psoriasis is a highly effective anti-inflammatory treatment in the short term; an immunohistochemical study

Climatotherapy is a well‐described treatment of psoriasis. Dead Sea climatotherapy (DSC) in Israel consists of intensive sun and Dead Sea bathing and is very effective in improving clinical and patient‐reported outcomes. However, the effect of DSC has not been widely studied. We aimed to investigate the effect of DSC on psoriasis skin using quantitative immunohistochemistry techniques and analysis of blood samples. Skin punch biopsies from 18 psoriasis patients from a previous cohort study were used. Biopsies were obtained from non‐lesional skin and from a psoriasis target lesion at baseline. A biopsy was acquired from the target lesion after DSC. Among patients who achieved complete visual clearance, a biopsy was also obtained at relapse. Blood samples were obtained at the same time points. We performed haematoxylin and eosin staining and quantitative immunohistochemical analysis of CD3, CD4, CD8, CD11c, CD103, CD163, CD207, forkhead box P3, Ki67 and myeloperoxidase. We performed blood tests of cholesterol, c‐reactive protein, glucose, haemoglobin A1c and triglycerides. All skin biomarkers except for CD207 were decreased after DSC. At relapse, none of the biomarkers were significantly different from the baseline lesional measurements. Total CD207 staining correlated with psoriasis area and severity index at baseline while CD163 staining correlated with psoriasis area and severity index at EOT. No changes were observed in selected blood tests during the study. Consistent with clinical results, DSC is highly effective in the short term almost normalising all investigated biomarkers. However, at relapse, biomarkers were upregulated to the baseline level.