The IL-23/IL-17 Pathway in Inflammatory Skin Diseases: From Bench to Bedside

Neuroinflammation evoked mechanisms for neuropathic itch in the spared nerve injury mouse model of neuropathic pain

A large portion of neuropathic pain suffering patients may also concurrently experience neuropathic itch, with a negative impact on the quality of life. The limited understanding of neuropathic itch and the low efficacy of current anti-itch therapies dictate the urgent need of a better comprehension of molecular mechanisms involved and development of relevant animal models. This study was aimed to characterize the itching phenotype in a model of trauma-induced peripheral neuropathy, the spared nerve injury (SNI), and the molecular events underlying the overlap with the nociceptive behavior. SNI mice developed hyperknesis and spontaneous itch 7-14 days after surgery that was prevented by gabapentin treatment. Itch was associated with pain hypersensitivity, loss of intraepidermal nerve fiber (IENF) density and increased epidermal thickness. In coincidence with the peak of scratching behavior, SNI mice showed a spinal overexpression of IBA1 and GFAP, microglia and astrocyte markers respectively. An increase of the itch neuropeptide B-type natriuretic peptide (BNP) in NeuN+ cells, of its downstream effector interleukin 17 (IL17) along with increased pERK1/2 levels occurred in the spinal cord dorsal horn and DRG. A raise in BNP and IL17 was also detected at skin level. Stimulation of HaCat cells with conditioned medium from BV2-stimulated SH-SY5Y cells produced a dramatic reduction of HaCat cell viability. This study showed that SNI mice might represent a model for neuropathic itch and pain. Collectively, our finding suggest that neuropathic itch might initiate at spinal level, then affecting skin epidermis events, through a glia-mediated neuroinflammation-evoked BNP/IL17 mechanism.

Gut microbiota and skin pathologies: Mechanism of the gut-skin axis in atopic dermatitis and psoriasis

Atopic dermatitis (AD) and psoriasis are chronic skin diseases with a global impact, posing significant challenges to public health systems and severely affecting patients' quality of life. This review delves into the key role of the gut microbiota in these diseases, emphasizing the importance of the gut-skin axis in inflammatory mediators and immune regulation and revealing a complex bidirectional communication system. We comprehensively assessed the pathogenesis, clinical manifestations, and treatment strategies for AD and psoriasis, with a particular focus on how the gut microbiota and their metabolites influence disease progression via the gut-skin axis. In addition, personalized treatment plans based on individual patient microbiome characteristics have been proposed, offering new perspectives for future treatment approaches. We call for enhanced interdisciplinary cooperation to further explore the interactions between gut microbiota and skin diseases and to assess the potential of drugs and natural products in modulating the gut-skin axis, aiming to advance the treatment of skin diseases.

Unlocking milk thistle's anti-psoriatic potential in mice: Targeting PI3K/AKT/mTOR and KEAP1/NRF2/NF-κB pathways to modulate inflammation and oxidative stress

Silybum marianum, known as milk thistle (MT), is traditionally used to manage liver diseases. This study aimed to investigate the role of MT extract topical application as a potential treatment for imiquimod (IMQ)-induced psoriatic lesions in mice with particular emphasis on phosphoinositol-3 Kinase (PI3K)/ protein kinase B (AKT)/ mammalian target of rapamycin (mTOR) and Kelch-like ECH-associated protein 1 (KEAP1)/ nuclear factor erythroid-2-related factor (NRF2)/ nuclear factor-kappa B (NF-κB) molecular cascades involvement. To address this aim, forty male Swiss albino mice were subdivided into four groups (n = 10 mice/group): control, IMQ model, standard group where mice were treated topically with IMQ, then the anti-psoriatic mometasone cream, and MT extract-treated group where mice were treated topically with IMQ followed by MT extract. In most measured parameters, MT extract, rich in silymarin, exhibited potent anti-psoriatic activity comparable to the standard cortisone treatment. MT extract mitigated dorsal skin erythema, scaling, and epidermal thickening, reflected by lowering the Psoriasis Area Severity Index (PASI) score. Moreover, it alleviated IMQ-induced splenomegaly. Mechanistically, the PI3K/AKT/mTOR pathway was the main functional pathway behind such improvements, where it was significantly inhibited by MT extract application. This led to NRF2 activation via KEAP1 downregulation with subsequent anti-inflammatory effect proven by reducing NF-κB, interleukin (IL)-23, and IL-17A and antioxidant ability proven by boosting the antioxidant glutathione and heme oxygenase-1. Such improvements were confirmed by alleviating the histopathological alteration. Thus, MT extract could be a promising therapeutic agent for psoriasis treatment by inhibiting PI3K/AKT/mTOR cascade, along with NRF2 signaling activation.

Peripheral and central regulation of neuro-immune crosstalk

The neural and immune systems sense and respond to external stimuli to maintain tissue homeostasis. These systems do not function independently but rather interact with each other to effectively exert biological actions and prevent disease pathogenesis, such as metabolic, inflammatory, and infectious disorders. Mutual communication between these systems is also affected by tissue niche-specific signals that reflect the tissue environment. However, the regulatory mechanisms underlying these interactions are not completely understood. In addition to the peripheral regulation of neuro-immune crosstalk, recent studies have reported that the central nervous system plays essential roles in the regulation of systemic neuro-immune interactions. In this review, we provide an overview of the molecular basis of peripheral and systemic neuro-immune crosstalk and explore how these multilayered interactions are maintained.

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

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

Flavonoid compounds and their synergistic effects: Promising approaches for the prevention and treatment of psoriasis with emphasis on keratinocytes - A systematic and mechanistic review

Psoriasis, a chronic autoimmune skin disorder, causes rapid and excessive skin cell growth due to immune system dysfunction. Numerous studies have shown that flavonoids have anti-psoriatic effects by modulating various molecular mechanisms involved in inflammation, cytokine production, keratinocyte proliferation, and more. This study reviewed experimental data reported in scientific literature and used network analysis to identify the potential biological roles of flavonoids' targets in treating psoriasis. 947 records from Web of Sciences, ScienceDirect database, Scopus, PubMed, and Cochrane library were reviewed without limitations until June 26, 2023. 66 articles were included in the systematic review. The ten genes with the highest scores, including interleukin (IL)-10, IL-12A, IL-1β, IL-6, Tumor necrosis factor-α (TNF-α), Janus kinase 2 (JAK 2), Jun N-terminal kinase (JUN), Proto-oncogene tyrosine-protein kinase Src (SRC), Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), and Signal transducer and activator of transcription 3 (STAT3), were identified as the hub genes. KEGG pathway analysis identified connections related to inflammation and autoimmune responses, which are key characteristics of psoriasis. IL-6, STAT3, and JUN's presence in both hub and enrichment genes suggests their important role in flavonoid's effect on psoriasis. This comprehensive study highlights how flavonoids can target biological processes in psoriasis, especially when combined for enhanced effectiveness.

Cellular indexing of transcriptomes and epitopes (CITE-Seq) in hidradenitis suppurativa identifies dysregulated cell types in peripheral blood and facilitates diagnosis via machine learning

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition characterized by painful nodules, abscesses, and scarring, predominantly affecting intertriginous regions and it is often underdiagnosed. This study aimed to utilize single cell RNA and cell-surface protein sequencing (CITE-Seq) to delineate the immune composition of circulating cells in Hidradenitis suppurativa (HS) peripheral blood compared to healthy controls. CITE-Seq was used to analyze the gene and protein expression profiles of peripheral blood mononuclear cells (PBMCs) from 9 HS and 29 healthy controls. The study identified significant differences cell composition between HS patients and healthy controls, including increased proportions of CD14+ and CD16+ monocytes, cDC2, plasmablasts, and proliferating CD4+ T cells in HS patients. Differential expression analysis revealed upregulation of inflammatory markers such as TNF, IL1B, and NF-κB in monocytes, as well as chemokines and cell adhesion molecules involved in immune cell recruitment and tissue infiltration. Pathway enrichment analysis highlighted the involvement of IL-17, IL-26 and TNF signaling pathways in HS pathogenesis. Machine learning identified key markers for diagnostics and therapeutic development. The findings also support the potential for machine learning models to aid in the diagnosis of HS based on immune cell markers. These insights may inform future therapeutic strategies targeting specific immune pathways in HS.

The Impact of Thyroiditis on the Immune Profile in Young Patients with Uncomplicated Type 1 Diabetes

Autoimmune thyroid disease (AIT) is the most frequently linked autoimmune condition to type 1 diabetes (T1D). The analysis of immune profiles could provide valuable insights into the study of these diseases. This knowledge could play a crucial role in understanding the relationship between immune profiles and microcirculation structures and functions. The present study aimed to test the hypothesis that cytokine levels in T1D patients without and those with comorbid Hashimoto's disease differ significantly. The total study group (total T1D) consisted of 62 diabetic young patients: 43 T1D and 19 T1D + AIT matched for age, age at onset, and duration of diabetes. The control group consisted of 32 healthy young subjects. The levels of cytokines (including TNF-α, IL-35, IL-4, IL-10, IL-18, IL-12, VEGF, and angiogenin) were quantified throughout this investigation. A comparative assessment of the cytokines profiles between the control group and total T1D revealed a statistically significant elevation in the levels of IL-4, TNF-α, IL-18, VEGF, and angiogenin, accompanied by a notable decline in IL-10. However, IL-35 and IL-12 exhibited comparable levels between the two groups. A comparison of cytokine levels between T1D + AIT and T1D groups revealed that only angiogenin levels were statistically significantly higher in T1D + AIT. The results of our study indicated that the alterations in cytokine levels associated with AIT did not correspond to the observed changes in T1D-related outcomes. The sole notable observation was the elevation of angiogenin expression, an angiogenic factor.

Neutrophil exhaustion and impaired functionality in psoriatic arthritis patients

Background

Neutrophils (polymorphonuclear leukocytes, PMNs) are the most abundant subtype of white blood cells and are among the main actors in the inflammatory response. Psoriatic arthritis (PsA) is a chronic inflammatory disease affecting both the axial and peripheral joints. Typically associated with psoriasis, PsA can also affect multiple systems and organs, including the nails and entheses. Despite the involvement of PMNs in PsA, their specific role in the disease remains poorly understood. This study aimed to characterize the biological functions of PMNs and neutrophil-related mediators in PsA patients.

Materials and methods

31 PsA patients and 22 healthy controls (HCs) were prospectively recruited. PMNs were isolated from peripheral blood and subjected to in vitro stimulation with lipopolysaccharide (LPS), N-Formylmethionyl-leucyl-phenylalanine (fMLP), tumor necrosis factor (TNF), phorbol 12-myristate 13-acetate (PMA), or control medium. Highly purified peripheral blood PMNs (>99%) were evaluated for activation status, reactive oxygen species (ROS) production, phagocytic activity, granular enzyme and neutrophil extracellular traps (NETs) release. Serum levels of matrix metalloproteinase-9 (MMP-9), myeloperoxidase (MPO), TNF, interleukin 23 (IL-23), and interleukin 17 (IL-17) were measured by ELISA. Serum Citrullinated histone H3 (CitH3) was measured as a NET biomarker.

Results

Activated PMNs from PsA patients displayed reduced activation, decreased ROS production, and impaired phagocytic activity upon stimulation with TNF, compared to HCs. PMNs from PsA patients also displayed reduced granular enzyme (MPO) and NET release. Serum analyses revealed elevated levels of MMP-9, MPO, TNF, IL-23, IL-17, and CitH3 in PsA patients compared to HCs. Serum CitH3 levels positively correlated with MPO and TNF concentrations, and IL-17 concentrations were positively correlated with IL-23 levels in PsA patients. These findings indicate that PMNs from PsA patients show reduced in vitro activation and function, and an increased presence of neutrophil-derived mediators (MMP-9, MPO, TNF, IL-23, IL-17, and CitH3) in their serum.

Conclusions

Taken together, our findings suggest that PMNs from PsA patients exhibit an "exhausted" phenotype, highlighting their plasticity and multifaceted roles in PsA pathophysiology.

The role of cytokines in the pathogenesis of SAPHO syndrome

SAPHO syndrome is a complex inflammatory disorder affecting the skin and bones, characterized by osteomyelitis, acne, and pustulosis. Cytokines play a pivotal role in the pathogenesis of SAPHO syndrome, especially in inflammatory responses and immune regulation. This article reviews the cytokines involved in the pathogenesis of SAPHO syndrome, such as tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), IL-6, IL-10, and transforming growth factor-β (TGF-β), and discusses their potential as intervention points for treatment. These findings elucidate the intricate immune regulatory network of SAPHO syndrome and provide a theoretical foundation for the development of new targeted therapeutic strategies.

Efficacy and Safety of Brodalumab, an Anti-interleukin-17 Receptor A Monoclonal Antibody, for Palmoplantar Pustulosis: 16-Week Results of a Randomized Clinical Trial

BACKGROUND

Palmoplantar pustulosis (PPP), a refractory skin disease characterized by repeated eruptions of sterile pustules and vesicles on palms and/or soles, involves interleukin-17 pathway activation. Brodalumab, a fully human anti-interleukin-17 receptor A monoclonal antibody, is being investigated for use in PPP treatment.

OBJECTIVE

The aim was to assess the efficacy and safety of brodalumab in Japanese PPP patients with moderate or severe pustules/vesicles.

METHODS

A phase 3, randomized, double-blind, placebo-controlled trial was conducted between July 2019 and August 2022, at 41 centers in Japan. Patients aged 18-70 years with a diagnosis of PPP for ≥ 24 weeks, a PPP Area Severity Index (PPPASI) score of ≥ 12, a PPPASI subscore of pustules/vesicles of ≥ 2, and inadequate response to therapy were included. Participants were randomized 1:1 to receive brodalumab 210 mg or placebo, subcutaneously (SC) at baseline, weeks 1 and 2, and every 2 weeks (Q2W) thereafter until week 16. Changes from baseline to week 16 in the PPPASI total score (primary endpoint) and other secondary skin-related endpoints and safety endpoints were assessed.

RESULTS

Of the 126 randomized patients, 50 of 63 in the brodalumab group and 62 of 63 in the placebo group completed the 16-week period. Reasons for discontinuation were adverse event (n = 6), withdrawal by patient/parent/guardian (n = 3), progressive disease (n = 3), and lost to follow-up (n = 1) in the brodalumab group and Good Clinical Practice deviation (n = 1) in the placebo group. Change from baseline in the PPPASI total score at week 16 was significantly higher (p = 0.0049) with brodalumab (least-squares mean [95% confidence interval {CI}] 13.73 [10.91-16.56]) versus placebo (8.45 [5.76-11.13]; difference [95% CI] 5.29 [1.64-8.94]). At week 16, brodalumab showed a trend of rapid improvement versus placebo for PPPASI-50/75/90 response (≥ 50%/75%/90% improvement from baseline) and Physician's Global Assessment 0/1 score: 54% versus 24.2%, 36.0% versus 8.1%, 16.0% versus 0.0%, and 32.0% versus 9.7%, respectively. Infection was the dominant treatment-emergent adverse event (TEAE); the commonly reported TEAEs were otitis externa (25.4%/1.6%), folliculitis (15.9%/3.2%), nasopharyngitis (14.3%/4.8%), and eczema (14.3%/12.9%) in the brodalumab/placebo groups, respectively. The severity of most TEAEs reported was Grade 1 or 2 and less frequently Grade ≥ 3.

CONCLUSIONS

Brodalumab SC 210 mg Q2W demonstrated efficacy in Japanese PPP patients. The most common TEAEs were mild infectious events.

TRIAL REGISTRATION

NCT04061252 (Date of Trial Registration: August 19, 2019).

Therapeutic Potential and Mechanisms of Mesenchymal Stem Cell and Mesenchymal Stem Cell-Derived Extracellular Vesicles in Atopic Dermatitis

Atopic dermatitis (AD) is a chronic and inflammatory skin disease with intense itchiness that is highly prevalent worldwide.The pathogenesis of AD is complex and closely related to genetic factors, immunopathogenic factors, environmental factors, and skin infections. Mesenchymal stem cells (MSCs) are non-hematopoietic progenitor cells derived from the mesenchymal stroma. They have anti-inflammatory, anti-apoptotic, and regenerative properties. Numerous studies demonstrate that MSCs can play a therapeutic role in AD by regulating various immune cells, maintaining immune homeostasis, and promoting the repair of damaged tissues. The key mediators for their biological functions are extracellular vesicles (MSC-Evs) and soluble cytokines derived from MSCs. The safety and efficacy of MSCs have been demonstrated in clinical Phase I / IIa trials for AD. This paper provides a comprehensive review of the pathogenesis of AD and the currently published studies on the function of MSCs and MSC-Evs in AD, primarily including the pathogenesis and the immunomodulatory impacts of MSCs and MSC-Evs, along with advancements in clinical studies. It provides insights for comprehending AD pathogenesis and investigating treatments based on MSCs.

Increased expression of psoriasin (S100A7) and interleukin 17 (IL-17) in lesional skin in lichen planopilaris

Introduction

Lichen planopilaris (LPP) is an inflammatory, primary scarring alopecia, however its pathogenesis is not completely elucidated. S100A7 is a multifunctional, antimicrobial protein with proinflammatory properties. Interleukin-17 (IL-17) is implicated in the development of various autoimmune skin diseases.

Aim

To determine the tissue expression of S100A7, S100A4 and IL-17 in LPP.

Material and methods

The immunohistochemical analysis was performed on biopsy specimens obtained from individuals with histologically confirmed lichen planopilaris (n = 23), alopecia areata (AA) (n = 11), and healthy controls (n = 14). The expression was evaluated using Zeiss Axio Imager A2 light microscope.

Results

The number of cells showing S100A7 expression was significantly higher in LPP lesional skin compared to AA lesional skin (p = 0.0002) and normal skin of healthy controls (p < 0.0001). The number of cells showing IL-17 expression was significantly higher in LPP lesional skin compared to normal skin of healthy controls (p < 0.0001) and the number of cells showing IL-17 expression was significantly higher in AA lesional skin compared to normal skin of healthy controls (p < 0.0001). The number of cells showing IL-17 expression was not significantly different in LPP lesional skin and in AA lesional skin (p > 0.05). The number of cells showing S100A4 expression was not significantly different in LPP lesional skin, AA lesional skin and in normal skin of healthy controls.

Conclusions

The results of our study suggest the possible role of S100A7 and IL-17 in the pathogenesis of LPP.

Unveiling the value of C-reactive protein as a severity biomarker and the IL4/IL13 pathway as a therapeutic target in recessive dystrophic epidermolysis bullosa: A multiparametric cross-sectional study

Patients with recessive dystrophic epidermolysis bullosa (RDEB) experience numerous complications, which are exacerbated by inflammatory dysregulation and infection. Understanding the immunological mechanisms is crucial for selecting medications that balance inflammation control and immunocompetence. In this cross-sectional study, aiming to identify potential immunotherapeutic targets and inflammatory biomarkers, we delved into the interrelationship between clinical severity and systemic inflammatory parameters in a representative RDEB cohort. Encompassing 84 patients aged 1-67 and spanning all three Epidermolysis Bullosa Disease Activity and Scarring Index (EBDASI) severity categories, we analysed the interrelationship of infection history, standard inflammatory markers, systemic cytokines and Ig levels to elucidate their roles in RDEB pathophysiology. Our findings identify C-reactive protein as an excellent biomarker for disease severity in RDEB. A type 2 inflammatory profile prevails among moderate and severe RDEB patients, correlating with dysregulated circulating IgA and IgG. These results underscore the IL4/IL13 pathways as potential evidence-based therapeutic targets. Moreover, the complete inflammatory scenario aligns with Staphylococcus aureus virulence mechanisms. Concurrently, abnormalities in IgG, IgE and IgM levels suggest an immunodeficiency state in a substantial number of the cohort's patients. Our results provide new insights into the interplay of infection and immunological factors in the pathogenesis of RDEB.

Hidradenitis suppurativa: a new therapeutic approach for an old disease

Hidradenitis suppurativa (HS) is a chronic inflammatory disease characterised by recurrent painful nodules, abscesses, fistulas and scarring. The primary distinguishing factor in the complex, yet still not fully understood, pathogenesis is an inflammation occurring within the hair follicle, followed by an immune response leading to further development of the skin lesions seen in HS. The treatment of patients with HS is very difficult due to the complexity of the lesions and the frequent tendency to recurrence, which also has a negative impact on the psychological state of patients and directly translates into a reduced quality of life. This review article addresses the pathogenesis, clinical presentation of HS and, in particular, explores the new therapeutic options available.

Emerging Role of Biologic Drugs Targeting IL-17 and IL-23: Pityriasis Rubra Pilaris

Pityriasis rubra pilaris (PRP) is a rare, papulosquamous, inflammatory skin disease. PRP represents a therapeutic challenge. The rarity of this disease and its possible spontaneous remission makes the conduction and interpretation of therapeutic studies particularly difficult. Moreover, PRP not infrequently proves resistant to common topical and conventional systemic therapies. In this context, numerous biologic agents have been reported in PRP treatment. The aim of our manuscript was to review the current literature to evaluate the possible role of biologics targeting the IL17/23 axis in PRP management. Recent cases in the literature have highlighted the use of several promising drugs: IL-17 inhibitors, IL-23 inhibitors, and the IL-12/23p40 inhibitor ustekinumab. However, it should be noted that all these drugs are approved for moderate-to-severe plaque psoriasis and their use in PRP is off label. The treatment of PRP is based on clinical experience, case reports or case series reported in the literature, as randomized controlled trials are difficult to conduct due to the rarity of the condition. Despite data on the efficacy of drugs targeting IL-17 and IL-23 being promising, they are still limited. Certainly, further studies are desirable to better characterize PRP and establish shared guidelines.

Hair follicles modulate skin barrier function

Our skin provides a protective barrier that shields us from our environment. Barrier function is typically associated with the interfollicular epidermis; however, whether hair follicles influence this process remains unclear. Here, we utilize a potent genetic tool to probe barrier function by conditionally ablating a quintessential epidermal barrier gene, Abca12, which is mutated in the most severe skin barrier disease, harlequin ichthyosis. With this tool, we deduced 4 ways by which hair follicles modulate skin barrier function. First, the upper hair follicle (uHF) forms a functioning barrier. Second, barrier disruption in the uHF elicits non-cell-autonomous responses in the epidermis. Third, deleting Abca12 in the uHF impairs desquamation and blocks sebum release. Finally, barrier perturbation causes uHF cells to move into the epidermis. Neutralizing IL-17a, whose expression is enriched in the uHF, partially alleviated some disease phenotypes. Altogether, our findings implicate hair follicles as multi-faceted regulators of skin barrier function.

Therapeutic Effect of Lecigel, Cetiol®CC, Activonol-6, Activonol-M, 1,3-Propanediol, Soline, and Fucocert® (LCAA-PSF) Treatment on Imiquimod-Induced Psoriasis-like Skin in Mice

The individual ingredients of 1,3-Propanediol, Soline, and Fucocert® (PSF) are often used as cosmetic formulations in skin care. In addition, the mixture of Lecigel, Cetiol®CC, Activonol-6, and Activonol-M (LCAA) is often used as a cosmetic base. However, whether the combination of LCAA with PSF (LCAA-PSF) exerts a therapeutic effect on psoriasis remains unclear. In this study, mice induced with imiquimod (IMQ) were divided into three groups and administered 100 mg/day of LCAA, 100 mg/day of LCAA-PSF, or Vaseline on the dorsal skin of each mouse. Weight-matched mice treated with Vaseline alone were used as controls. Hematoxylin and eosin (H&E) staining and enzyme-linked immunosorbent assay(ELISA) were used to assess tissue morphology and inflammatory cytokines. RNA sequencing analysis was used to predict the mechanism underlying the action of LCAA-PSF against psoriasis, while immunohistochemical analysis validation was used to identify pertinent molecular pathways. The results demonstrated that LCAA-PSF alleviated IMQ-induced keratinocyte differentiation/ proliferation bydecreasingthe serum levels of inflammatory cytokines such as IL-6, TNF-α, IL-23, and IL-17A and the epidermisof TGFβ, Ki67, CK5/6, and VEGF expression, which is associated with angiogenesis and keratinocyte differentiation/ proliferation. These findings highlight the antipsoriatic activity of LCAA-PSF in a psoriasis-like mouse model and suggest this may occurvia the inhibition of inflammatory factor secretionand the TGFβ-related signal pathway.

A Novel Human Interleukin-23A Overexpressing Mouse Model of Systemic Lupus Erythematosus

OBJECTIVE

Interleukin-23 (IL-23) is a crucial cytokine implicated in chronic inflammation and autoimmunity, associated with various diseases such as psoriasis, psoriatic arthritis, and systemic lupus erythematosus (SLE). This study aimed to create and characterize a transgenic mouse model overexpressing human IL-23A (TghIL-23A), providing a valuable tool for investigating the pathogenic role of human IL-23A and evaluating the efficacy of anti-human IL-23A therapeutics.

METHODS

TghIL-23A mice were generated via microinjection of CBA × C57BL/6 zygotes with a fragment of the human IL23A gene, flanked by its 5'-regulatory sequences and the 3' untranslated region of human β-globin. The TghIL-23A pathology was assessed through hematologic and biochemic analyses, cytokine and antinuclear antibody detection, and histopathologic examination of skin and renal tissues. The response to the anti-human IL-23A therapeutic agent guselkumab was evaluated in groups of eight mixed-sex mice receiving subcutaneous treatment twice weekly for 10 weeks using clinical, biomarker, and histopathologic readouts.

RESULTS

TghIL-23A mice exhibited interactions between human IL-23A and mouse IL-23/IL-12p40 and developed a chronic multiorgan autoimmune disease marked by proteinuria, anti-double-stranded DNA antibodies, severe inflammatory lesions in the skin, and milder phenotypes in the kidneys and lungs. The TghIL-23A pathologic features exhibited significant similarities to those observed in human patients with SLE, and they were reversed following guselkumab treatment.

CONCLUSION

We have generated and characterized a novel genetic mouse model of SLE, providing proof-of-concept for the etiopathogenic role of human IL-23A. This new model has a normal life span and integrates several characteristics of the human disease's complexity and chronicity, making it an attractive preclinical tool for studying IL-23-dependent pathogenic mechanisms and assessing the efficacy of anti-human IL-23A or modeled disease-related therapeutics.

Cordycepin Ameliorates Psoriasis-Like Skin Lesion by Regulating p53/MDM2 Feedback Loop

Apoptosis is a natural physiological process of programmed cell death. It is essential for maintaining the homeostasis of the body and the immune system. The dysfunction of apoptosis can lead to the development of autoimmune diseases. In psoriasis, the dysfunction of keratinocyte proliferation manifests as an impairment of apoptosis. Cordycepin is the major active component in cordyceps militaris and has pharmacological effects, including regulation of apoptosis. The pharmacological mechanism of Cordycepin in psoriasis remains unclear. In this study, bioinformatics analysis revealed that the mechanism may be associated with the p53 apoptotic pathway. Further, we confirmed in the experiments that cordycepin inhibited the interleukin (IL)-17A-induced proliferation of HaCaT cells and down-regulated the expression of proliferating cell nuclear antigen (PCNA) and Ki-67. Regulating the expression of apoptotic proteins BAX, Bcl-2, and p53 promote apoptosis. Further investigation of the upstream pathway of apoptosis revealed that cordycepin could normalize the abnormal p53-mouse double minute 2 (MDM2) feedback loop. In vivo results showed that the cordycepin gel could effectively improve imiquimod (IMQ)-induced psoriasis-like skin lesions in mice, and the p53-MDM2 pathway was verified at the protein level. In conclusion, the anti-psoriasis effect of Cordycepin and its potential mechanism have not been discussed in detail. However, our work supports the idea that Cordycepin can be further developed as an Active Pharmaceutical Ingredient (API) for the treatment of psoriasis.

Single-cell analysis identifies conserved features of immune dysfunction in simulated microgravity and spaceflight

Microgravity is associated with immunological dysfunction, though the mechanisms are poorly understood. Here, using single-cell analysis of human peripheral blood mononuclear cells (PBMCs) exposed to short term (25 hours) simulated microgravity, we characterize altered genes and pathways at basal and stimulated states with a Toll-like Receptor-7/8 agonist. We validate single-cell analysis by RNA sequencing and super-resolution microscopy, and against data from the Inspiration-4 (I4) mission, JAXA (Cell-Free Epigenome) mission, Twins study, and spleens from mice on the International Space Station. Overall, microgravity alters specific pathways for optimal immunity, including the cytoskeleton, interferon signaling, pyroptosis, temperature-shock, innate inflammation (e.g., Coronavirus pathogenesis pathway and IL-6 signaling), nuclear receptors, and sirtuin signaling. Microgravity directs monocyte inflammatory parameters, and impairs T cell and NK cell functionality. Using machine learning, we identify numerous compounds linking microgravity to immune cell transcription, and demonstrate that the flavonol, quercetin, can reverse most abnormal pathways. These results define immune cell alterations in microgravity, and provide opportunities for countermeasures to maintain normal immunity in space.

Challenges in Psoriasis Research: A Systematic Review of Preclinical Models

INTRODUCTION

Psoriasis is a chronic inflammatory skin disease with variable clinical presentation, multifactorial etiology and an immunogenetic basis. Several studies demonstrate that it results from a dysregulated interaction between skin keratinocytes, immune cells, and the environment that leads to a persistent inflammatory process modulated by cytokines and T cells. The development of new treatment options requires increased understanding of pathogenesis. However, the successful implementation of effective drugs requires well-characterized and highly available preclinical models that allow researchers to quickly and reproducibly determine their safety and efficacy.

METHODS

A systematic search on PubMed and Scopus databases was performed and assessed to find appropriate articles about psoriasis models applying the key words previously defined. The PRISMA guidelines were employed.

RESULTS

A total of 45 original articles were selected that met the selection criteria. Among these, there are articles on in vivo, in vitro, and ex vivo models, with the in vitro model being the majority due to its ease of use. Within animal models, the most widely used in recent years are chemically induced models using a compound known as imiquimod. However, the rest of the animal models used throughout the disease's research were also discussed. On the other hand, in vitro models were divided into two and three dimensions. The latter were the most used due to their similarity to human skin. Lastly, the ex vivo models were discussed, although they were the least used due to their difficulty in obtaining them.

CONCLUSIONS

Therefore, this review summarizes the current preclinical models (in vivo, in vitro, and ex vivo), discussing how to develop them, their advantages, limitations, and applications. There are many challenges to improve the development of the different models. However, research in these in vitro model studies could reduce the use of animals. This is favored with the use of future technologies such as 3D bioprinting or organ-on-a-chip technologies.

Cytokine-Mediated Molecular Pathophysiology of Hidradenitis Suppurativa: A Narrative Review

Background

Hidradenitis suppurativa (HS) is a chronic inflammatory condition of the skin that mainly affects the apocrine gland-rich intertriginous areas. The disease manifests as painful nodules, abscesses, and pus-filled tunnels, which can severely impact patient's quality of life. While diagnosis is clinical, successful treatment options for this condition are limited. There has been an increase in research and clinical trials focusing on biomarkers and cytokines for clinical use. Understanding the potential biomarkers and cytokines implicated in HS pathogenesis may allow efficacious and safe treatment options.

Summary

A literature review was conducted on nine biomarkers and cytokines. IL-1, IL-10, IL-17, IL-23, TNF-α, YKL-40, G-CSF, NOD2, and the complement system were identified due to their potential clinical utilization and pathophysiological involvement in HS.

Key Messages

With further research expanding our understanding of the pathophysiology of HS and the roles these cytokines and biomarkers play, there is potential for utilization as diagnostic markers or development of antagonists against these specific agents for HS management.

IL-17 in wound repair: bridging acute and chronic responses

Chronic wounds, resulting from persistent inflammation, can trigger a cascade of detrimental effects including exacerbating inflammatory cytokines, compromised blood circulation at the wound site, elevation of white blood cell count, increased reactive oxygen species, and the potential risk of bacterial infection. The interleukin-17 (IL-17) signaling pathway, which plays a crucial role in regulating immune responses, has been identified as a promising target for treating inflammatory skin diseases. This review aims to delve deeper into the potential pathological role and molecular mechanisms of the IL-17 family and its pathways in wound repair. The intricate interactions between IL-17 and other cytokines will be discussed in detail, along with the activation of various signaling pathways, to provide a comprehensive understanding of IL-17's involvement in chronic wound inflammation and repair.

CD169+ Skin Macrophages Function as a Specialized Subpopulation in Promoting Psoriasis-like Skin Disease in Mice

Skin macrophages are critical to maintain and restore skin homeostasis. They serve as major producers of cytokines and chemokines in the skin, participating in diverse biological processes such as wound healing and psoriasis. The heterogeneity and functional diversity of macrophage subpopulations endow them with multifaceted roles in psoriasis development. A distinct subpopulation of skin macrophages, characterized by high expression of CD169, has been reported to exist in both mouse and human skin. However, its role in psoriasis remains unknown. Here, we report that CD169+ macrophages exhibit increased abundance in imiquimod (IMQ) induced psoriasis-like skin lesions. Specific depletion of CD169+ macrophages in CD169-ditheria toxin receptor (CD169-DTR) mice inhibits IMQ-induced psoriasis, resulting in milder symptoms, diminished proinflammatory cytokine levels and reduced proportion of Th17 cells within the skin lesions. Furthermore, transcriptomic analysis uncovers enhanced activity in CD169+ macrophages when compared with CD169- macrophages, characterized by upregulated genes that are associated with cell activation and cell metabolism. Mechanistically, CD169+ macrophages isolated from IMQ-induced skin lesions produce more proinflammatory cytokines and exhibit enhanced ability to promote Th17 cell differentiation in vitro. Collectively, our findings highlight the crucial involvement of CD169+ macrophages in psoriasis development and offer novel insights into the heterogeneity of skin macrophages in the context of psoriasis.

Metabolic dysfunction associated steatotic liver disease in patients with plaque psoriasis: a case-control study and serological comparison

Background

The relationship between plaque psoriasis and both MASLD and lean MASLD has not been sufficiently explored in the current literature.

Method

This retrospective and observational study was carried out from January 2021 to January 2023 at The First Affiliated Hospital of Zhejiang Chinese Medical University. Patients diagnosed with plaque psoriasis and a control group consisting of individuals undergoing routine physical examinations were enrolled. The incidence of MASLD and lean MASLD among these groups was compared. Additionally, patients with plaque psoriasis were divided into those with MASLD, those with lean MASLD, and a control group with only psoriasis for a serological comparative analysis.

Results

The incidence of MASLD in the observation group and the control group was 43.67% (69/158) and 22.15% (35/158), respectively (p < 0.01). Furthermore, the incidence of lean MASLD within the observation group and the control group was 10.76% (17/158) and 4.43% (7/158), respectively (p < 0.01). After controlling for potential confounding variables, plaque psoriasis was identified as an independent risk factor for MASLD with an odds ratio of 1.88 (95% cl: 1.10-3.21). In terms of serological comparison, compared to the simple psoriasis group, we observed a significant elevation in the tumor marker CYFRA21-1 levels in both groups compared to the control group with simple psoriasis (p < 0.01). Moreover, the MASLD group exhibited elevated levels of inflammatory markers and psoriasis score, whereas these effects were mitigated in the lean MASLD group.

Conclusion

The prevalence of MASLD and lean MASLD is higher among patients with psoriasis. Those suffering from psoriasis along with MASLD show increased psoriasis scores and inflammatory markers compared to those without metabolic disorders. MASLD likely worsens psoriasis conditions, indicating the necessity of targeted health education for affected individuals to reduce the risk of MASLD, this education should include guidelines on exercise and diet. In serological assessments, elevated levels of cytokeratin 19 fragment (CYFRA21-1) were noted in both MASLD and lean MASLD groups, implying a potential synergistic role between psoriasis and MASLD.

Periodic heat waves-induced neuronal etiology in the elderly is mediated by gut-liver-brain axis: a transcriptome profiling approach

Heat stress exposure in intermittent heat waves and subsequent exposure during war theaters pose a clinical challenge that can lead to multi-organ dysfunction and long-term complications in the elderly. Using an aged mouse model and high-throughput sequencing, this study investigated the molecular dynamics of the liver-brain connection during heat stress exposure. Distinctive gene expression patterns induced by periodic heat stress emerged in both brain and liver tissues. An altered transcriptome profile showed heat stress-induced altered acute phase response pathways, causing neural, hepatic, and systemic inflammation and impaired synaptic plasticity. Results also demonstrated that proinflammatory molecules such as S100B, IL-17, IL-33, and neurological disease signaling pathways were upregulated, while protective pathways like aryl hydrocarbon receptor signaling were downregulated. In parallel, Rantes, IRF7, NOD1/2, TREM1, and hepatic injury signaling pathways were upregulated. Furthermore, current research identified Orosomucoid 2 (ORM2) in the liver as one of the mediators of the liver-brain axis due to heat exposure. In conclusion, the transcriptome profiling in elderly heat-stressed mice revealed a coordinated network of liver-brain axis pathways with increased hepatic ORM2 secretion, possibly due to gut inflammation and dysbiosis. The above secretion of ORM2 may impact the brain through a leaky blood-brain barrier, thus emphasizing intricate multi-organ crosstalk.

Mild cognitive impairment in pemphigus

BACKGROUND

Pemphigus is a group of autoimmune blistering disorders that have been associated with dementia in previous studies. Mild cognitive impairment (MCI) can be the first stage of progression into dementia. The objective of the present study was to evaluate the frequency of MCI in pemphigus patients compared to a control group.

METHODS

This case-control study included 80 patients with pemphigus referred to the dermatology clinics of Shohadaye Tajrish and Loghman Hakim hospitals, Tehran, Iran, in 2021. A group of 80 individuals without pemphigus who visited the same clinics for cosmetic consultation or interventions were regarded as controls. Age, sex, marital status, and education were recorded for all participants. Disease duration, medications, and severity were noted for pemphigus patients. The Persian version of the Montreal Cognitive Assessment (MoCA) test was used to assess cognitive function.

RESULTS

MCI was significantly more frequent in pemphigus patients than in controls (55% vs. 37.5%, P = 0.026). Furthermore, the total MoCA score was significantly lower in pemphigus patients compared to controls (23.98 ± 3.77 vs. 25.21 ± 3.45, P = 0.032); however, among MoCA's different domains, only the executive functions score was significantly lower in pemphigus patients (P = 0.010). After adjustment, multivariable logistic regression analysis revealed that every 1-year higher education in patients decreased the odds of MCI by 52% (adjusted odds ratio = 0.483, 95% confidence interval 0.326; 0.715, P < 0.001).

CONCLUSIONS

The frequency of MCI was found to be significantly higher, and overall scores of the MoCA test, as well as its executive function domain, were significantly lower among pemphigus patients in this study compared to the control group. Additionally, a higher level of education was associated with decreased odds of MCI in pemphigus patients. Identifying pemphigus patients with MCI through the use of the MoCA test can facilitate early intervention, enabling them to seek help and support.

The mind-skin connection: A narrative review exploring the link between inflammatory skin diseases and psychological stress

Inflammatory skin diseases are known to negatively impact patient psychology, with individuals experiencing higher rates of stress and subsequent diminished quality of life, as well as mental health issues including anxiety and depression. Moreover, increased psychological stress has been found to exacerbate existing inflammatory skin diseases. The association between inflammatory skin diseases and psychological stress is a timely topic, and a framework to better understand the relationship between the two that integrates available literature is needed. In this narrative review article, we discuss potential neurobiological mechanisms behind psychological stress due to inflammatory skin diseases, focusing mainly on proinflammatory cytokines in the circulating system (the brain-gut-skin communications) and the default mode network in the brain. We also discuss potential descending pathways from the brain that lead to aggravation of inflammatory skin diseases due to psychological stress, including the central and peripheral hypothalamic-pituitary-adrenal axes, peripheral nerves and the skin barrier function.

Association of the Complement System with Subclinical Atherosclerosis in Psoriasis: Findings from an Observational Cohort Study

Psoriasis is a chronic and inflammatory disease that affects the skin and joints and is associated with multiple comorbidities and cardiovascular risk factors. Consequently, patients with psoriasis have an increased risk of cardiovascular diseases such as atherosclerosis, a chronic pathology that shares common inflammatory and immune-response mechanisms with psoriasis, including vascular inflammation and complement activation. To better understand the relationship between atherosclerosis and psoriasis, a proteomics study followed by a bioinformatics analysis was carried out, with a subsequent validation step using ELISA and western blotting. When the plasma from patients with psoriasis alone was compared with that from patients with psoriasis and atherosclerosis, 31 proteins of interest related to the complement system and oxygen transport were identified. After the validation phase, 11 proteins appeared to define the presence of subclinical atherosclerosis in patients with psoriasis, indicating the importance of complement cascades in the development of atherosclerotic plaques in individuals with psoriasis. These results are a step forward in understanding the pathological pathways implicated in the cardiovascular risk associated with this population, which may represent an interesting starting point for developing predictive tools that improve the follow-up of these patients and design more effective therapies.

Hair follicles modulate skin barrier function

Our skin provides a protective barrier that shields us from our environment. Barrier function is typically associated with interfollicular epidermis; however, whether hair follicles influence this process remains unclear. Here, we utilize a potent genetic tool to probe barrier function by conditionally ablating a quintessential epidermal barrier gene, Abca12, which is mutated in the most severe skin barrier disease, harlequin ichthyosis. With this tool, we deduced 4 ways by which hair follicles modulate skin barrier function. First, the upper hair follicle (uHF) forms a functioning barrier. Second, barrier disruption in the uHF elicits non-cell autonomous responses in the epidermis. Third, deleting Abca12 in the uHF impairs desquamation and blocks sebum release. Finally, barrier perturbation causes uHF cells to move into the epidermis. Neutralizing Il17a, whose expression is enriched in the uHF, partially alleviated some disease phenotypes. Altogether, our findings implicate hair follicles as multi-faceted regulators of skin barrier function.

The therapeutic efficacy and mechanism action of Si Cao formula in the treatment of psoriasis: A pilot clinical investigation and animal validation

ETHNOPHARMACOLOGICAL RELEVANCE

Psoriasis is a chronic inflammation and relapsing disease that affected approximately 100 million individuals worldwide. In previous clinical study, it was observed that the topical application of Si Cao Formula (SCF) ameliorated psoriasis skin lesions and reduced the recurrence rate of patients over a period of three months. However, the precise mechanism remains unclear.

AIM OF THE STUDY

The objective of this study was to assess the effectiveness and safety of SCF in patients diagnosed with psoriasis and explore the molecular mechanisms that contribute to SCF's therapeutic efficacy in psoriasis treatment.

MATERIALS AND METHODS

A randomized, controlled, and pilot clinical study was performed. This study assessed 30 individuals diagnosed with mild to moderate plaque psoriasis. 15 of them underwent local SCF treatment, the others received calcipotriol intervention. The outcome measure focused on Psoriasis Area and Severity Index (PASI), Dermatology Life Quality Index (DLQI), and recurrence rate. In addition, IMQ-induced psoriasis-like mice model were used to assess the impact of SCF on ameliorating epidermal hyperplasia, suppressing angiogenesis, and modulating immune response. Furthermore, we performed bioinformatics analysis on transcriptome data obtained from skin lesions of mice model. This analysis allowed us to identify the targets and signaling pathways associated with the action of SCF. Subsequently, we conducted experimental validation to confirm the core targets.

RESULTS

Our clinical pilot study demonstrated that SCF could ameliorate skin lesions in psoriasis patients with comparable efficacy of calcipotriol in drop of PASI and DLQI scores. SCF exhibited a significantly reduced recurrence rate within 12 weeks (33.3%). Liquid Chromatography Mass Spectrometry (LC-MS) identified 41 active constituents of SCF (26 cations and 15 anions). Animal experiments showed SCF ameliorates the skin lesions of IMQ-induced psoriasis like mice model and suppresses epidermal hyperkeratosis and angiogenesis. There were 845 up-regulated and 764 down-regulated DEGs between IMQ and IMQ + SCF groups. GO analysis revealed that DEGs were linked to keratinization, keratinocyte differentiation, organic acid transport epidermal cell differentiation, and carboxylic acid transport interferon-gamma production. KEGG pathway analysis showed that SCF may play a vital part through IL-17 and JAK/STAT signaling pathway. In addition, SCF could reduce the number of positive cells expressing PCNA, CD31, pSTAT3, CD3, and F4/80 within the epidermis of psoriatic lesions, as well as the expression of Il-17a and Stat3 in IMQ-induced psoriasis mice.

CONCLUSIONS

Our research suggests that SCF serves as a reliable and efficient local approach for preventing and treating psoriasis. The discovery of plausible molecular mechanisms and therapeutic targets associated with SCF may support its broad implementation in clinical settings.

Th17 Cell and Inflammatory Infiltrate Interactions in Cutaneous Leishmaniasis: Unraveling Immunopathogenic Mechanisms

The inflammatory response during cutaneous leishmaniasis (CL) involves immune and non-immune cell cooperation to contain and eliminate Leishmania parasites. The orchestration of these responses is coordinated primarily by CD4+ T cells; however, the disease outcome depends on the Th cell predominant phenotype. Although Th1 and Th2 phenotypes are the most addressed as steers for the resolution or perpetuation of the disease, Th17 cell activities, especially IL-17 release, are recognized to be vital during CL development. Th17 cells perform vital functions during both acute and chronic phases of CL. Overall, Th17 cells induce the migration of phagocytes (neutrophils, macrophages) to the infection site and CD8+ T cells and NK cell activation. They also provoke granzyme and perforin secretion from CD8+ T cells, macrophage differentiation towards an M2 phenotype, and expansion of B and Treg cells. Likewise, immune cells from the inflammatory infiltrate have modulatory activities over Th17 cells involving their differentiation from naive CD4+ T cells and further expansion by generating a microenvironment rich in optimal cytokines such as IL-1β, TGF-β, IL-6, and IL-21. Th17 cell activities and synergies are crucial for the resistance of the infection during the early and acute stages; however, if unchecked, Th17 cells might lead to a chronic stage. This review discusses the synergies between Th17 cells and the inflammatory infiltrate and how these interactions might destine the course of CL.

The Immunology of Psoriasis-Current Concepts in Pathogenesis

Psoriasis is one of the most common inflammatory skin diseases with a chronic, relapsing-remitting course. The last decades of intense research uncovered a pathological network of interactions between immune cells and other types of cells in the pathogenesis of psoriasis. Emerging evidence indicates that dendritic cells, TH17 cells, and keratinocytes constitute a pathogenic triad in psoriasis. Dendritic cells produce TNF-α and IL-23 to promote T cell differentiation toward TH17 cells that produce key psoriatic cytokines IL-17, IFN-γ, and IL-22. Their activity results in skin inflammation and activation and hyperproliferation of keratinocytes. In addition, other cells and signaling pathways are implicated in the pathogenesis of psoriasis, including TH9 cells, TH22 cells, CD8+ cytotoxic cells, neutrophils, γδ T cells, and cytokines and chemokines secreted by them. New insights from high-throughput analysis of lesional skin identified novel signaling pathways and cell populations involved in the pathogenesis. These studies not only expanded our knowledge about the mechanisms of immune response and the pathogenesis of psoriasis but also resulted in a revolution in the clinical management of patients with psoriasis. Thus, understanding the mechanisms of immune response in psoriatic inflammation is crucial for further studies, the development of novel therapeutic strategies, and the clinical management of psoriasis patients. The aim of the review was to comprehensively present the dysregulation of immune response in psoriasis with an emphasis on recent findings. Here, we described the role of immune cells, including T cells, B cells, dendritic cells, neutrophils, monocytes, mast cells, and innate lymphoid cells (ILCs), as well as non-immune cells, including keratinocytes, fibroblasts, endothelial cells, and platelets in the initiation, development, and progression of psoriasis.

Bridging the gender gap in autoimmunity with T-cell-targeted biomaterials

Autoimmune diseases are caused by malfunctions of the immune system and generally impact women at twice the frequency of men. Many of the most serious autoimmune diseases are accompanied by a dysregulation of T-cell phenotype, both regarding the ratio of CD4+ to CD8+ T-cells and proinflammatory versus regulatory phenotypes. Biomaterials, in the form of particles and hydrogels, have shown promise in ameliorating this dysregulation both in vivo and ex vivo. In this review, we explore the role of T-cells in autoimmune diseases, particularly those with high incidence rates in women, and evaluate the promise and efficacy of innovative biomaterial-based approaches for targeting T-cells.

Unravelling the anti-inflammatory mechanism of Allium cepa: an integration of network pharmacology and molecular docking approaches

Allium cepa, commonly known as onion, is a widely consumed spice that possesses numerous pharmacological properties. A. cepa bioactive components are often explored in the treatment of inflammation-related complications. However, the molecular mechanism via which they exert their anti-inflammatory effects remains unknown. Therefore, this study aimed to elucidate the anti-inflammatory mechanism of A. cepa bioactive components. Consequently, the bioactive compounds of A. cepa were obtained from a database, while the potential targets of the sixty-nine compounds with desirable pharmacokinetic properties were predicted. Subsequently, the targets of inflammation were acquired from the GeneCards database. The protein-protein interaction (PPI) between the sixty-six shared targets of the bioactive compounds and inflammation was retrieved from the String database and visualized using Cytoscape v3.9.1 software. Gene Ontology (GO) analysis of the ten core targets from the PPI network revealed that A. cepa bioactive compounds could be involved in regulating biological processes such as response to oxygen-containing compounds and response to inflammation while Kyoto Encyclopaedia of Genes and Genomes (KEGG) analysis revealed that A. cepa compounds might modulate pathways including AGE-RAGE signaling pathway, interleukin (IL)-17 signalling pathway, and tumor necrosis factor signaling pathway. Molecular docking analysis showed that 1-O-(4-Coumaroyl)-beta-D-glucose, stigmasterol, campesterol, and diosgenin have high binding affinities for core targets including EGFR, ALB, MMP9, CASP3, and CCL5. This study successfully elucidated the potential anti-inflammatory mechanism of A. cepa bioactive compounds, hence, providing new insights into the development of alternative anti-inflammatory drugs.

Hidradenitis suppurativa as a potential risk factor of periodontitis: a multi-center, propensity-score-matched cohort study

Background: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease associated with systemic symptoms. Periodontitis, a prevalent dental disease, shares immune-mediated inflammatory characteristics with HS. This cohort study aims to evaluate the association between HS and periodontitis. Methods: Using the TriNetX research network, a global-federated database of electronic health records, we conducted a retrospective cohort study. People being diagnosed of HS were identified and propensity score matching was performed to identify proper control group, via balancing critical covariates Within the follow-up time of 1 year, 3 year and 5 years, hazard ratios were calculated to assess the risk of periodontitis in HS patients compared to controls. Results: Within the 53,968 HS patients and the same number of matched controls, the HS patients exhibited a significantly increased risk of developing periodontitis compared to controls after 3 years of follow-up (HR: 1.64, 95% CI: 1.11, 2.44) and 5 years of follow-up (HR: 1.64, 95% CI: 1.21, 2.24) of follow-up. Sensitivity analyses supported these findings under various matching models and washout periods. While comparing with patients with psoriasis, the association between HS and periodontitis remained significant (HR: 1.73, 95% CI: 1.23, 2.44). Conclusion: The observed increased risk suggests the need for heightened awareness and potential interdisciplinary care for individuals with HS to address periodontal health.

Theoretical Studies of DNA Microarray Present Potential Molecular and Cellular Interconnectivity of Signaling Pathways in Immune System Dysregulation

Autoimmunity is defined as the inability to regulate immunological activities in the body, especially in response to external triggers, leading to the attack of the tissues and organs of the host. Outcomes include the onset of autoimmune diseases whose effects are primarily due to dysregulated immune responses. In past years, there have been cases that show an increased susceptibility to other autoimmune disorders in patients who are already experiencing the same type of disease. Research in this field has started analyzing the potential molecular and cellular causes of this interconnectedness, bearing in mind the possibility of advancing drugs and therapies for the treatment of autoimmunity. With that, this study aimed to determine the correlation of four autoimmune diseases, which are type 1 diabetes (T1D), psoriasis (PSR), systemic sclerosis (SSc), and systemic lupus erythematosus (SLE), by identifying highly preserved co-expressed genes among datasets using WGCNA. Functional annotation was then employed to characterize these sets of genes based on their systemic relationship as a whole to elucidate the biological processes, cellular components, and molecular functions of the pathways they are involved in. Lastly, drug repurposing analysis was performed to screen candidate drugs for repositioning that could regulate the abnormal expression of genes among the diseases. A total of thirteen modules were obtained from the analysis, the majority of which were associated with transcriptional, post-transcriptional, and post-translational modification processes. Also, the evaluation based on KEGG suggested the possible role of TH17 differentiation in the simultaneous onset of the four diseases. Furthermore, clomiphene was the top drug candidate for regulating overexpressed hub genes; meanwhile, prilocaine was the top drug for regulating under-expressed hub genes. This study was geared towards utilizing transcriptomics approaches for the assessment of microarray data, which is different from the use of traditional genomic analyses. Such a research design for investigating correlations among autoimmune diseases may be the first of its kind.

Unraveling the skin; a comprehensive review of atopic dermatitis, current understanding, and approaches

Atopic dermatitis, also known as atopic eczema, is a chronic inflammatory skin disease characterized by red pruritic skin lesions, xerosis, ichthyosis, and skin pain. Among the social impacts of atopic dermatitis are difficulties and detachment in relationships and social stigmatization. Additionally, atopic dermatitis is known to cause sleep disturbance, anxiety, hyperactivity, and depression. Although the pathological process behind atopic dermatitis is not fully known, it appears to be a combination of epidermal barrier dysfunction and immune dysregulation. Skin is the largest organ of the human body which acts as a mechanical barrier to toxins and UV light and a natural barrier against water loss. Both functions face significant challenges due to atopic dermatitis. The list of factors that can potentially trigger or contribute to atopic dermatitis is extensive, ranging from genetic factors, family history, dietary choices, immune triggers, and environmental factors. Consequently, prevention, early clinical diagnosis, and effective treatment may be the only resolutions to combat this burdensome disease. Ensuring safe and targeted drug delivery to the skin layers, without reaching the systemic circulation is a promising option raised by nano-delivery systems in dermatology. In this review, we explored the current understanding and approaches of atopic dermatitis and outlined a range of the most recent therapeutics and dosage forms brought by nanotechnology. This review was conducted using PubMed, Google Scholar, and ScienceDirect databases.

Microwave ablation enhances the systemic immune response in patients with lung cancer

Microwave ablation (MWA) is a key alternative therapy to conventional surgery for the treatment of lung cancer. In addition to eliminating local tumors, MWA may promote antitumor immunological responses, such as abscopal effects in distant lesions. However, the intensity of MWA is limited and the underlying mechanisms are not well-defined. The present study assessed the impact of MWA on immune cell subsets and cytokines in patients with lung cancer. A total of 45 patients with lung cancer who underwent percutaneous lung tumor MWA were enrolled. Peripheral blood samples were collected before and 24 h after MWA and changes in immune cell subsets [lymphocytes, CD3+, CD4+ and CD8+ T cells, B cells and natural killer (NK) cells] and serum cytokine levels (IL-1β, IL-2, IL-4-6, IL-8, IL-10, IL-12p70, IL-17A and F, IL-22, TNF-α, TNF-β and IFN-γ) were assessed by flow cytometry and ELISA. The number of total lymphocytes, CD4+ T and NK cells in the peripheral blood significantly decreased 24 h after MWA, while number of CD8+ T cells remained stable, leading to a higher proportion of CD8+ T cells. In addition, the serum levels of IL-2, IL-1β, IL-6, IL-12p70, IL-22, TNF-α and IFN-γ were significantly increased 24 h after MWA, indicating a T helper 1 type immune response. The immune response in patients with advanced stage disease was comparable with patients in the early stage group; however, the number of total lymphocytes and CD3+ T cells significantly decreased and the ratio of CD4/CD8 and IL-2 levels significantly increased. The early immune response after MWA may contribute to systemic antitumor immunity in patients with both early and advanced disease. Thus, MWA may exhibit potential as a local therapy and trigger abscopal effects in distant lesions in patients with lung cancer.

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.

Human Amniotic MSC Response in LPS-Stimulated Ascites from Patients with Cirrhosis: FOXO1 Gene and Th17 Activation in Enhanced Antibacterial Activation

Spontaneous bacterial peritonitis (SBP) is a severe complication in patients with decompensated liver cirrhosis and is commonly treated with broad spectrum antibiotics. However, the rise of antibiotic resistance requires alternative therapeutic strategies. As recently shown, human amnion-derived mesenchymal stem cells (hA-MSCs) are able, in vitro, to promote bacterial clearance and modulate the immune and inflammatory response in SBP. Our results highlight the upregulation of FOXO1, CXCL5, CXCL6, CCL20, and MAPK13 in hA-MSCs as well as the promotion of bacterial clearance, prompting a shift in the immune response toward a Th17 lymphocyte phenotype after 72 h treatment. In this study, we used an in vitro SBP model and employed omics techniques (next-generation sequencing) to investigate the mechanisms by which hA-MSCs modify the crosstalk between immune cells in LPS-stimulated ascitic fluid. We also validated the data obtained via qRT-PCR, cytofluorimetric analysis, and Luminex assay. These findings provide further support to the hope of using hA-MSCs for the prevention and treatment of infective diseases, such as SBP, offering a viable alternative to antibiotic therapy.

HMGB1 regulates Th17 cell differentiation and function in patients with psoriasis

BACKGROUND

Psoriasis is an immune-mediated chronic inflammatory skin disease, in which T helper 17 (Th17) cells and its effective cytokine interleukin (IL)-17A play a pivotal pathogenic role. High mobility group box 1 (HMGB1) is an important proinflammatory cytokine, which has been confirmed to be highly expressed in the peripheral circulation and epidermis tissues of psoriasis patients. The regulatory effect of HMGB1 on IL-17A expression and function has been reported in some inflammatory and autoimmune diseases by the HMGB1-Toll-like receptor 4 (TLR4)-interleukin (IL)-23-IL-17A pathway. While, in the pathological environment of psoriasis, whether HMGB1 can exert the regulatory effect on IL-17A is not clear.

OBJECTIVE

We aimed to evaluate the role of HMGB1-TLR4-IL-23-IL-17A pathway in the pathogenesis of psoriasis and explore the possible regulatory mechanism of HMGB1 on Th17 cell differentiation.

METHODS

Serum levels of HMGB1, TLR4, IL-23, and IL-17A were quantified in 50 patients with moderate-to-severe plaque psoriasis and 30 healthy controls. Peripheral blood mononuclear cells  were acquired from 10 severe psoriasis patients and administrated by different concentrations of recombinant-HMGB1 (rHMGB1) to detect the Th17 cell percentage, mRNA and protein levels of TLR4, IL-23, IL-17A and retinoid-related orphan receptor γt (RORγt).

RESULTS

The serum levels of HMGB1, TLR4, IL-23, and IL-17A in psoriasis patients were significantly higher than healthy controls, especially in severe patients, and positively correlated with the severity index. There were also positive correlations between every two detected indicators of HMGB1, TLR4, IL-23, and IL-17A. In vitro study, rHMGB1 can promote the elevated expression of Th17 cell percentage as well as TLR4, IL-23, IL-17A, and RORγt in a dose-dependent manner.

CONCLUSION

HMGB1 can contribute to the pathogenesis of psoriasis by regulating Th17 cell differentiation through HMGB1-TLR4-IL-23-RORγt pathway, then promotes IL-17A production and aggravates inflammation process. Targeting HMGB1 may be a possible potential candidate for the immunotherapy of psoriasis.

Hidradenitis Suppurativa: An Understanding of Genetic Factors and Treatment

Hidradenitis suppurativa (HS), recognized as a chronic and debilitating skin disease, presents significant challenges in both diagnosis and treatment. This review explores the clinical manifestations, genetic landscape, and molecular mechanisms underlying HS. The disease's association with a predisposing genetic background, obesity, smoking, and skin occlusion underscores the complexity of its etiology. Genetic heterogeneity manifests in sporadic, familial, and syndromic forms, with a focus on mutations in the γ-secretase complex genes, particularly NCSTN. The dysregulation of immune mediators, including TNF-α, IL-17, IL-1β, and IL-12/23, plays a crucial role in the chronic inflammatory nature of HS. Recent advancements in genetic research have identified potential therapeutic targets, leading to the development of anti-TNF-α, anti-IL-17, anti-IL-1α, and anti-IL-12/23 therapies and JAK inhibitors. These interventions offer promise in alleviating symptoms and improving the quality of life for HS patients.

Exploring the causal relationship between inflammatory cytokines and immunoinflammatory dermatoses: a Mendelian randomization study

Objectives

Previous studies have shown that the onset and progression of several immunoinflammatory dermatoses are closely related to specific immune-inflammatory responses. To further assess the causal relationship between 41 inflammatory cytokines and immunoinflammatory dermatoses, we used a Mendelian randomization method.

Methods

Mendelian two-sample randomization utilized inflammatory cytokines from a GWAS abstract containing 8,293 healthy participants as well as psoriasis (4,510 cases and 212,242 controls), atopic dermatitis (7,024 cases and 198,740 controls), and vitiligo (131 cases and 207,482 controls). The causal relationship between exposure and outcome was explored primarily using inverse variance weighting. In addition, multiple sensitivity analyses, including MR-Egger, weighted median, simple model, weighted model, and MR-PRESSO, were simultaneously applied to enhance the final results.

Results

The results showed that in clinical practice, IL-4 and IL-1RA were suggestive indicators of atopic dermatitis risk (OR = 0.878, 95% CI = 0.78-0.99, p = 0.036; OR = 0.902, 95% CI = 0.82-1.00, p = 0.045). SCGF-b was a suggestive indicator of psoriasis risk (OR = 1.095, 95% CI = 1.01-1.18, p = 0.023). IL-4 is a suggestive indicator of vitiligo risk (OR = 2.948, 95% CI = 1.28-6.79, p = 0.011).

Conclusion

Our findings suggest that circulating inflammatory cytokines may play a crucial role in the pathogenesis of chronic skin inflammation. IL-4 and IL-1RA may have inhibitory roles in the risk of developing atopic dermatitis, while SCGF-b may have a promoting role in the risk of developing psoriasis. Furthermore, IL-4 may contribute to the risk of developing vitiligo. These results provide insights into further understanding the mechanisms of chronic skin inflammation and offer new targets and strategies for the prevention and treatment of related diseases.

Single-cell analysis of psoriasis resolution demonstrates an inflammatory fibroblast state targeted by IL-23 blockade

Biologic therapies targeting the IL-23/IL-17 axis have transformed the treatment of psoriasis. However, the early mechanisms of action of these drugs remain poorly understood. Here, we perform longitudinal single-cell RNA-sequencing in affected individuals receiving IL-23 inhibitor therapy. By profiling skin at baseline, day 3 and day 14 of treatment, we demonstrate that IL-23 blockade causes marked gene expression shifts, with fibroblast and myeloid populations displaying the most extensive changes at day 3. We also identify a transient WNT5A+/IL24+ fibroblast state, which is only detectable in lesional skin. In-silico and in-vitro studies indicate that signals stemming from these WNT5A+/IL24+ fibroblasts upregulate multiple inflammatory genes in keratinocytes. Importantly, the abundance of WNT5A+/IL24+ fibroblasts is significantly reduced after treatment. This observation is validated in-silico, by deconvolution of multiple transcriptomic datasets, and experimentally, by RNA in-situ hybridization. These findings demonstrate that the evolution of inflammatory fibroblast states is a key feature of resolving psoriasis skin.

A systematic review of Janus kinase inhibitors and spleen tyrosine kinase inhibitors for Hidradenitis suppurativa treatment

BACKGROUNDS AND AIMS

Hidradenitis suppurativa (HS) is a challenging skin disease with an underlying inflammatory process. Substantial progress has been made in our understanding of HS over the last few years, with the advancement of novel treatment approaches. The current systematic review aims to evaluate the safety and efficacy of Janus kinase (JAK) inhibitors and spleen tyrosine kinase (Syk) inhibitors in treating HS.

METHOD

A thorough systematic search was performed on PubMed/Medline, Web of Science, and Ovid Embase databases up to September 23th, 2023. Clinical studies published in English were included.

RESULTS

Our search yielded ten articles with a total of 165 patients treated with four types of JAK inhibitors (upadacitinib, povorcitinib, tofacitinib, and baricitinib) and one Syk inhibitor (fostamatinib). Upadacitinib, povorcitinib, and tofacitinib improved clinical outcomes, with a significant reduction in hidradenitis suppurativa clinical response (HiSCR) and abscess and inflammatory nodule count (AN count) during the treatment period. Also, these drugs are well tolerated in most HS patients with minimal adverse events (AEs). Moreover, baricitinib depicted an amelioration in signs and symptoms of HS in one case report. Also, fostamatinib exhibited favorable tolerability throughout a 12-week in moderate-to-severe HS patients. The remarkable clinical improvement, as assessed through HiSCR and hidradenitis suppurativa severity (IHS4), corresponded closely with serological indicators of inflammation following fostamatinib administration was achieved.

CONCLUSION

JAK and Syk inhibitors are potentially efficacious in managing moderate-to-severe HS since the proinflammatory cytokines are mediated by JAK and Syk signaling pathways. However, further research with a more rigorous examination is mandatory to evaluate such medication's long-term safety and efficacy.

Tryptophan, an important link in regulating the complex network of skin immunology response in atopic dermatitis

Atopic dermatitis (AD) is a common chronic relapsing inflammatory skin disease, of which the pathogenesis is a complex interplay between genetics and environment. Although the exact mechanisms of the disease pathogenesis remain unclear, the immune dysregulation primarily involving the Th2 inflammatory pathway and accompanied with an imbalance of multiple immune cells is considered as one of the critical etiologies of AD. Tryptophan metabolism has long been firmly established as a key regulator of immune cells and then affect the occurrence and development of many immune and inflammatory diseases. But the relationship between tryptophan metabolism and the pathogenesis of AD has not been profoundly discussed throughout the literatures. Therefore, this review is conducted to discuss the relationship between tryptophan metabolism and the complex network of skin inflammatory response in AD, which is important to elucidate its complex pathophysiological mechanisms, and then lead to the development of new therapeutic strategies and drugs for the treatment of this frequently relapsing disease.

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.

Assessment of safety profile of secukinumab in real-world scenario using United States food and drug administration adverse event reporting system database

Secukinumab is an anti-IL-17 monoclonal antibody approved for treating psoriasis and various arthritides. A comprehensive evaluation of its safety, especially in a real-world setting, is necessary. This study aimed to describe the adverse events (AE) associated with secukinumab use using the United States Food and Drug Administration Adverse Event Reporting System (FAERS) database. FAERS data files containing AE reports from 2015 to 2021 were downloaded for data mining. Primary or secondary suspect medications indicated for psoriasis were identified and analyzed. Medical dictionary for regulatory activities (MedDRA version 24.1) was used to analyze the AE terms. To detect potential safety signals of AE from secukinumab use, disproportionality analysis was used. A total of 365,590 adverse event reports were identified; of these, 44,761 reports involved the use of secukinumab. Safety signals were identified for ocular infections and gastrointestinal adverse events at the standardised MedDRA query level. Safety signals for oral candidiasis, oral herpes, conjunctivitis, eye infections, and ulcerative colitis were identified at the preferred term level. The findings of our study are consistent with those of earlier studies, such as the increased risk of infections and inflammatory bowel disease. However, our study also identified additional safety signals that need to be further evaluated.