The expression of mCTLA-4 in skin lesion inversely correlates with the severity of psoriasis

Psoriasis: What Is New in Markers of Disease Severity?

Introduction. Psoriasis is a chronic inflammatory skin disease and is the result of the interaction between numerous external and internal factors. Psoriasis presents a wide range of skin manifestations encompassing individual lesions varying from pinpoint to large plaques that can evolve into generalised forms. The lesions mirror the pathophysiological mechanisms involved in psoriasis pathogenesis, such as inflammation, dysregulation of immune response, uncontrolled proliferation of keratinocytes and angiogenesis. In this article, we present the latest advances achieved regarding markers that correlate with psoriasis severity. Material and method. We have performed a narrative review on markers of psoriasis severity, including articles published between March 2018-March 2023. Results. We have identified four categories of markers: inflammation markers, oxidative stress markers, hormonal markers and cancer-related markers. The main focus was on inflammation biomarkers, including immunomodulatory molecules, haematological parameters, inflammatory cells and costimulatory molecules. Conclusions. The analysed data indicate that markers associated with inflammation, oxidative stress and hormones, and cancer-related markers could be useful in assessing the severity of psoriasis. Nevertheless, additional research is required to ascertain the practical importance of these biomarkers in clinical settings.

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.

The elevation of plasma galectin-9 levels in patients with psoriasis and its associations with inflammatory and immune checkpoint molecules in skin tissues

Psoriasis is a chronic, immune-mediated disorder that mainly affects the skin, with an estimated global prevalence of 2-3%. Galectin-9 (Gal-9) is a β-galactoside-binding lectin capable of promoting or suppressing the progression of infectious and immune-mediated diseases. Here, we determined if the expression of Gal-9 is observed in psoriasis. Gal-9 levels were measured in plasma of psoriasis (n = 62) and healthy control (HC) (n = 31) using an enzyme-linked immunosorbent assay. In addition, skin samples from seven patients were screened for RNA transcriptomes and the expression of Gal-9 was compared with inflammatory, immune checkpoint molecules (ICMs) and Foxp3. The plasma Gal-9 levels in patients with psoriasis were significantly higher (841 pg/mL) than in HCs (617 pg/mL) (P < 0.0001) and were associated with white blood cell numbers, eosinophils (%) and alanine transaminase. The levels of inflammatory molecules IL-36B, IL-17RA, IL-6R, IL-10, IRF8, TGFb1, and IL-37, and those of ICMs of Tim-3, CTLA-4, CD86, CD80, PD-1LG2, CLEC4G, and Foxp3 were significantly correlated with Gal-9 (LGALS9) in skin. However, HMGB1, CD44, CEACAM1 and PDL1-known to be associated with a variety of Gal-9 biological functions were not correlated with LGALS9. Thus, it is likely that Gal-9 expression affects the disease state of PS.

Exploring the role of growth factors as potential regulators in psoriatic plaque formation

Psoriasis is a chronic inflammatory skin disease in which growth activity is more prominent than inflammatory activity at the centre of lesional skin (CE skin). This growth activity is partly influenced by growth factors (GFs) that play an important role in cell growth and inflammation during the plaque development. In this study, we identified potential GFs in CE skin and predicted their regulatory functions and biological activity in mediating transcripts in the plaques. Samples of uninvolved skin (UN skin) and CE skin were biopsied from patients with psoriasis vulgaris for RNA-sequencing analysis in order to identify differentially expressed genes (DEGs). Our finding revealed that epidermal growth factor (EGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF) and hepatocyte growth factor (HGF) signalling were enriched by CE/UN skin-derived DEGs. Additionally, several EGFR ligands, namely EGF, heparin-binding EGF like growth factor (HB-EGF), amphiregulin (AREG) and transforming growth factor (TGF)-α, as well as TGF-β1, TGF-β2, vascular endothelial growth factor-A, FGFs, PDGF-B and HGF, were predicted to be GF regulators. The regulatory pattern and biological activity of these GF regulators on mediating the CE/UN skin-derived DEGs was demonstrated. This study provides a novel hypothesis regarding the overall regulatory function of GFs, which appear to modulate the expression of the transcripts involved in inflammation and growth in the CE skin. In addition, some GFs may exert anti-inflammatory effects. Further investigations on the mechanisms underlying this regulation may contribute to a deeper understanding of psoriasis and the identification of potential therapeutic targets for patients with psoriasis.

Lipidomic profiling reveals metabolic signatures in psoriatic skin lesions

Psoriasis is a chronic immune-mediated inflammatory disease. Lipids play an important role in regulating the inflammatory response. However, the alteration of lipids involved in psoriasis particular in skin lesions remain unclear. Here, we performed the lipidomics to investigate lipid profiling in the skin lesions of the imiquimod-induced psoriasis-like dermatitis and psoriasis patients. The findings showed that ceramides phosphate (CerP) and ceramides were enriched in psoriatic lesions compared with controls from both psoriasis patients and psoriasis-like mouse model. Psoriasis patients were classified into two subtypes, the CC1 and CC2, by consensus clustering of these lipid signatures. The CC1 was characterized by the higher levels of CerP, uric acid, and more severe psoriasis, compared with CC2 subtype. Interestingly, ceramide-1-phosphate (C1P), dramatically enriched in CC1 subtype, facilitated imiquimod-induced psoriasis-like inflammatory responses. Mechanistically, C1P induced the expression of inflammatory factors and activated DNA replication and cell cycle signaling pathways in the primary keratinocytes. Inhibiting the production of C1P with ceramide kinase inhibitor effectively alleviated the imiquimod-induced psoriasis-like inflammation. Taken together, we described the landscape of lipids alteration and established lipids classification based on pattern of abundance of lipids in psoriatic skin lesions. Suppression of C1P pathway is a novel potential strategy for psoriasis treatment.

Inborn Errors of Immunity and Their Phenocopies: CTLA4 and PD-1

Elucidating links between genotype and phenotype in patients with rare inborn errors of immunity (IEIs) provides insights into mechanisms of immune regulation. In many autosomal dominant IEIs, however, variation in expressivity and penetrance result in complex genotype-phenotype relations, while some autosomal recessive IEIs are so rare that it is difficult to draw firm conclusions. Phenocopies arise when an environmental or non-genetic factor replicates a phenotype conferred by a specific genotype. Phenocopies can result from therapeutic antibodies or autoantibodies that target a protein to replicate aspects of the phenotype conferred by mutations in the gene encoding the same protein. Here, we consider IEIs arising from rare genetic variants in CTLA4 and PDCD1 and compare clinical and laboratory manifestations arising as drug-induced phenocopies (immune related adverse events, IRAEs) in cancer patients treated with immune checkpoint inhibitors (ICI) and identify outstanding questions regarding mechanism of disease.

Clinicoprognostic and Histopathological Features of Guttate and Plaque Psoriasis Based on PD-1 Expression

Several studies have determined the correlation between programmed cell death protein-1 (PD-1) and chronic plaque psoriasis (CPP). However, limited studies have assessed the association between PD-1 expression and the clinicoprognostic and distinct clinicopathological characteristics of CPP and guttate psoriasis (GP). Twenty-nine patients with skin biopsy-confirmed CPP were recruited at the Asan Medical Center between January 2018 and June 2020, and 33 patients with biopsy-confirmed GP were enrolled between January 2002 and June 2020. The clinicoprognostic and histopathological characteristics were analyzed according to immunohistochemical PD-1 expression in the epidermal or dermal inflammatory infiltrates. The CPP and GP lesions were divided into PD-1-low and PD-1-high groups. The CPP epidermal PD-1-high group had typical histopathological changes and significantly higher psoriasis area and severity index scores (p = 0.014) and disease duration (p = 0.009) than the epidermal PD-1-low group. In patients with GP, compared with the dermal PD-1-high group, the dermal PD-1-low group exhibited significantly higher disease duration (p = 0.002) and relapse rate of plaque psoriasis (p = 0.005) and significantly lower relapse-free survival (p = 0.016). Upregulated epidermal PD-1 expression was correlated with the chronicity and severity of CPP, while downregulated dermal PD-1 expression was correlated with poor prognosis of GP.

The Role of Co-Signaling Molecules in Psoriasis and Their Implications for Targeted Treatment

Psoriasis is a chronic, systemic immune-mediated inflammatory disease manifesting in the skin, joint or both. Co-signaling molecules are essential for determining the magnitude of the T cell response to the antigen. According to the function of co-signaling molecules, they can be divided into co-stimulatory molecules and co-inhibitory molecules. The role of co-signaling molecules in psoriasis is recognized, mainly including the co-stimulatory molecules CD28, CD40, OX40, CD27, DR3, LFA-1, and LFA-3 and the co-inhibitory molecules CTLA-4, PD-1, and TIM-3. They impact the pathological process of psoriasis by modulating the immune strength of T cells, regulating the production of cytokines or the differentiation of Tregs. In recent years, immunotherapies targeting co-signaling molecules have made significant progress and shown broad application prospects in psoriasis. This review aims to outline the possible role of co-signaling molecules in the pathogenesis of psoriasis and their potential application for the treatment of psoriasis.

Infliximab modifies regulatory T cells and co-inhibitory receptor expression on circulating T cells in psoriasis

BACKGROUND

Psoriasis is a T cell-mediated autoimmune skin disease. Accumulating evidence has demonstrated that co-inhibitory receptors (CIRs) play a vital role in regulating T cell-mediated immune response, especially in neoplasm and autoimmunity. However, the immuno-function of CIRs in the development of psoriasis remains unclear.

OBJECTIVE

We investigated the expression of CIRs on the circulating T lymphocytes of psoriasis patients before and after anti-tumor necrosis factor-α (TNF-α) therapy.

METHODS

We enrolled 17 patients with moderate-to-severe plaque psoriasis, 17 patients with mild plaque psoriasis, and 18 healthy controls in this study. Fourteen of the moderate-to-severe psoriasis patients were treated with infliximab, a monoclonal antibody against TNF-α. Peripheral blood was collected, and peripheral blood mononuclear cells were extracted. The proportion of T cell subsets along with their expression of CIRs, namely T cell immunoreceptor with Ig and ITIM domains (TIGIT), lymphocyte activating gene 3 (LAG-3), cytotoxic T-lymphocyte associated protein 4 (CTLA-4), B and T lymphocyte-associated protein (BTLA), endothelial protein C receptor (PROCR), podoplanin (PDPN), programmed cell death 1 (PD-1), and T cell immunoglobulin mucin family containing molecule 3 (TIM-3), were determined by flow cytometric assay.

RESULTS

The moderate-to-severe plaque psoriasis patients had less circulating Tregs, which increased after infliximab treatment. They also had decreased TIGIT, LAG-3 but increased PDPN expression on peripheral CD4⁺ T cells. Infliximab enhanced TIGIT, LAG-3, CTLA-4 but reduced PROCR expression on circulating CD4⁺ T cells. Remarkably, both the frequency of circulating Tregs and the expression level of TIGIT on CD4⁺ T cells at baseline (pre-treatment) negatively correlated with the extent of PASI score reduction benefited from infliximab therapy.

CONCLUSION

Anti-TNF-α therapy increased the frequency of Tregs and TIGIT, LAG-3, CTLA-4 expression but reduced PROCR expression on circulating CD4⁺ T cells in psoriasis patients. The baseline proportion of Tregs and the expression level of TIGIT on circulating CD4⁺ T cells might serve as predictive markers for the degree of disease remission benefited from infliximab treatment.

Acitretin Promotes the Differentiation of Myeloid-Derived Suppressor Cells in the Treatment of Psoriasis

Increased numbers of myeloid-derived suppressor cells (MDSCs) are involved in the development of psoriasis. Acitretin is used to treat psoriasis by regulating the proliferation and differentiation of keratinocytes, but little is known about the effect of acitretin on immune cells. Here, we reported that psoriasis patients had an expansion of MDSCs and monocytic-MDSCs (M-MDSCs) in peripheral blood and skin lesions. The number of MDSCs and M-MDSCs in peripheral blood correlated positively with disease severity. Acitretin could reduce the number of MDSCs and M-MDSCs in the peripheral blood of psoriasis patients as well as the spleen and skin lesions of IMQ-induced psoriasis-like model mice. Moreover, acitretin promoted the differentiation of MDSCs into macrophages, especially CD206⁺ M2 macrophages, and CD11c⁺MHC-II⁺ dendritic cells. Mechanically, acitretin dramatically increased the glutathione synthase (GSS) expression and glutathione (GSH) accumulation in MDSCs. Interruption of GSH synthesis abrogated the acitretin effect on MDSCs differentiation. Acitretin regulated GSS expression via activation of extracellular signal-regulated kinase 1/2. Thus, our data demonstrated a novel mechanism underlying the effects of acitretin on psoriasis by promoting MDSCs differentiation.

New insights into different adipokines in linking the pathophysiology of obesity and psoriasis

Psoriasis is a chronic, systemic, hyper-proliferative immune-mediated inflammatory skin disease. The results of epidemiological investigations have shown that psoriasis affects around 2% of the general population worldwide, and the total number of psoriasis patients is more than 6 million in China. Apart from the skin manifestations, psoriasis has been verified to associate with several metabolic comorbidities, such as insulin resistance, diabetes and obesity. However, the underlying mechanism is still not elucidated. Adipocytes, considered as the active endocrine cells, are dysfunctional in obesity which displays increased synthesis and secretion of adipokines with other modified metabolic properties. Currently, growing evidence has pointed to the central role of adipokines in adipose tissue and the immune system, providing new insights into the effect of adipokines in linking the pathophysiology of obesity and psoriasis. In this review, we summarize the current understanding of the pathological role of adipokines and the potential mechanisms whereby different adipokines link obesity and psoriasis. Furthermore, we also provide evidence which identifies a potential therapeutic target aiming at adipokines for the management of these two diseases.

The efficacy of psychological interventions on psoriasis treatment: a systematic review and meta-analysis of randomized controlled trials

Background

Previous observational studies have shown comorbidity between psoriasis and psychological disorders. However, the evidence of the efficacy of psychological interventions, including cognitive behavioral therapy (CBT) and other treatments, on psoriasis is still debated.

Objectives

The aim of this study was to systematically review the psychological interventions used in the treatment of psoriasis and to meta-analyze the efficacy of psychological interventions on psoriasis with respect to area and severity reduction.

Materials and methods

A systematic review and meta-analysis were conducted. PubMed, Web of Science, EMbase, and major Chinese academic journal databases were searched for articles published before January 2018. Studies of randomized controlled trials (RCTs) that applied psychological interventions in the treatment of psoriasis and used area and severity as the outcome measures were meta-analyzed. The pooled mean difference between groups was estimated using either fixed-effects models or random-effects models in the presence of heterogeneity. Subgroup analysis was performed by method of intervention and severity of psoriasis.

Results

Out of the 4,152 potentially relevant studies, 8 RCTs were included. The pooled mean difference was −1.36 (95% CI: −2.52 to −0.19; P=0.02). The pooled estimate was −1.80 (95% CI: −2.57 to −1.03; P<0.001) for CBT intervention and was −0.70 (95% CI: −2.39 to 0.99; P=0.42) for non-CBT intervention. The pooled estimates for mild and moderate-to-severe psoriasis were −1.95 (95% CI: −3.91 to 0.00; P=0.05) and −0.61 (95% CI: −1.61 to 0.38; P=0.23), respectively.

Conclusion

CBT is effective in the treatment of psoriasis in terms of area and severity reduction. Systemic treatment does not further enhance the efficacy of CBT. The effect of the psychological intervention is stronger in patients with moderate-to-severe psoriasis.

Abatacept in the treatment of psoriatic arthritis: biological and clinical profiles of the responders

Abatacept (CTLA4Ig), a selective T-cell costimulation modulator, has been approved for the treatment of psoriatic arthritis patients with an inadequate response to conventional synthetic disease-modifying antirheumatic drugs, but not for those with uncontrolled skin lesions, nor with axial involvement. In this review, we will try to interpret such a differential efficacy of abatacept on the psoriatic arthritis clinical domains, on the basis of its differential effectiveness on the diverse T-cell subsets at different sites. Clinical and biological profiles of possible responders to abatacept will be provided.

Frizzled-related proteins 4 (SFRP4) rs1802073G allele predicts the elevated serum lipid levels during acitretin treatment in psoriatic patients from Hunan, China

Background

Acitretin is a second-generation synthetic retinoid, and is widely used for treating the severe psoriasis vulgaris. However, it should be chosen with caution for its cardiovascular risk, and it is reported that acitretin may increase the serum lipids. The purpose of this study is to investigate the relationship between the Frizzled-related proteins 4 (SFRP4) rs1802073 polymorphism and the changes of serum lipids in Chinese psoriatic patients during the treatment with acitretin.

Methods

In our study, 100 psoriatic patients were recruited systematically treated with acitretin (30 mg/day) for at least eight weeks. Data of the patients’ demographic and clinical characteristics and the results of serum triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were collected pre- and post-treatment.

Results

A total of 84 psoriatic patients were enrolled and divided into three groups by SFRP4 rs1802073 genotypes. The patients who carried with TT genotype had maintained levels of TG and LDL-C after acitretin treatment, while patients with GG/GT genotypes had significantly elevated levels of serum TG and LDL-C compared to the TT genotype (ΔTG%: 27.53 ± 59.13 vs −1.47 ± 37.79, p = 0.026, ΔLDL-C%: 10.62 ± 26.57 vs −1.29 ± 17.07, p = 0.042). The association of rs1802073 with TG and LDL-C profiles remained significant after adjusting for age, gender, and body mass index. Although without significance, the pre-post change in serum level of TC across rs1802073 GG/GT genotypes demonstrated a trend similar to TG and LDL, and the serum level of HDL-C demonstrated a trend opposite to TG, TC and LDL.

Conclusions

Our results demonstrated that SFRP4 rs1802073 polymorphism was found to be associated with elevated serum lipid levels after acitretin treatment, and it may serve as a genetic marker of safe and precise treatment for individual psoriatic patients.