The IL-13-OVOL1-FLG axis in atopic dermatitis

Targeting IL-13 with tralokinumab normalizes type 2 inflammation in atopic dermatitis both early and at 2 years

BACKGROUND

Tralokinumab is a monoclonal antibody that specifically neutralizes interleukin (IL)-13, a key driver of skin inflammation and barrier abnormalities in atopic dermatitis (AD). This study evaluated early and 2-year impacts of IL-13 neutralization on skin and serum biomarkers following tralokinumab treatment in adults with moderate-to-severe AD.

METHODS

Skin biopsies and blood samples were evaluated from a subset of patients enrolled in the Phase 3 ECZTRA 1 (NCT03131648) and the long-term extension ECZTEND (NCT03587805) trials. Gene expression was assessed by RNA sequencing; protein expression was assessed by immunohistochemistry and immunoassay.

RESULTS

Tralokinumab improved the transcriptomic profile of lesional skin by Week 4. Mean improvements in the expression of genes dysregulated in AD were 39% at Week 16 and 85% at 2 years with tralokinumab, with 15% worsening at Week 16 with placebo. At Week 16, tralokinumab significantly decreased type 2 serum biomarkers (CCL17/TARC, periostin, and IgE), reduced epidermal thickness versus placebo, and increased loricrin coverage versus baseline. Two years of tralokinumab treatment significantly reduced expression of genes in the Th2 (IL4R, IL31, CCL17, and CCL26), Th1 (IFNG), and Th17/Th22 (IL22, S100A7, S100A8, and S100A9) pathways as well as increased expression of epidermal differentiation and barrier genes (CLDN1 and LOR). Tralokinumab also shifted atherosclerosis signaling pathway genes (SELE, IL-37, and S100A8) toward non-lesional expression.

CONCLUSION

Tralokinumab treatment improved epidermal pathology, reduced systemic markers of type 2 inflammation, and shifted expression of key AD biomarkers in skin towards non-lesional levels, further highlighting the key role of IL-13 in the pathogenesis of AD.

CLINICAL TRIAL REGISTRATION

NCT03131648, NCT03587805.

Atopic dermatitis: treatment and innovations in immunotherapy

Atopic dermatitis (AD) is a common inflammatory skin disease characterized by itching and skin barrier dysfunction. Moderate to severe AD is often refractory to first-line topical treatments, and systemic immunosuppressants have been shown to be effective but have significant adverse effects. The paucity of basic treatments has contributed to the development of targeted topical and systemic immunotherapies based on the use of small molecules and biologic drugs which can directly interact with AD pathogenetic pathways. They represent a new era of therapeutic innovation. Additional new treatments are desirable since AD is a heterogeneous disease marked by different immunological phenotypes. This manuscript will review the mechanism of action, safety profile, and efficacy of promising new systemic immunological treatments for AD. Since moderate to severe AD can result in poor quality of life, the development of targeted and well-tolerated immunomodulators is a crucial purpose. The introduction of new pharmacological agents may offer new therapeutic options. However, there is the need to evaluate how "narrow-acting" agents, such as individual interleukin inhibitors, will perform under the safety and efficacy profiles compared with "broad-acting" agents, such as JAK inhibitors.

Effectiveness and safety of systemic therapy for moderate-to-severe atopic dermatitis in children and adolescent patients: a systematic review

Importance

Due to comorbidities and associated safety risks, the management of severe atopic dermatitis (AD) in pediatric and adolescent patients poses significant challenges.

Objective

To examine the efficacy and safety of systemic therapies for the treatment of moderate-to-severe atopic dermatitis in children and adolescents.

Evidence review

On Feb 29, 2024, a systematic literature search was conducted in Embase, PubMed, and the Cochrane Central Register of Controlled Trials (Central). No date restrictions were applied. Randomized clinical trials, cohort studies, large case series, and meta-analyses were assessed to evaluate the efficacy (or effectiveness) and/or safety of systemic treatments for moderate-to-severe atopic dermatitis in children and adolescents.

Findings

A preliminary search yielded 1457 results, from which 19 unique articles with a total of 3741 patients were included in the analysis. Overall, the available data for each systemic medication are limited, and the overall quality of the included studies on conventional systemic treatments is relatively low. When Dupilumab was used as a standalone treatment, 30%-40% of infants and toddlers aged 6 months to 2 years achieved EASI-75, while 50% of patients aged 2 to 6 years achieved EASI-75. In children aged 6 to 12 years, 33.0%-59.0% of atopic dermatitis patients achieved EASI-75, and when combined with topical corticosteroids (TCS), 69.7%-74.6% achieved EASI-75. Long-term data showed EASI-75 rates ranging from 75.0% to 94.0% for this age group. For adolescents aged 12 to 18 years, 40%-71% of patients achieved EASI-75 within 12 to 16 weeks, and by week 52, 80.8% of patients achieved EASI-75.Abrocitinib treatment resulted in 68.5%-72.0% of patients achieving EASI-75. Omalizumab treatment at week 24 showed a percentage change in SCORAD scores of -12.4%. In the Methotrexate treatment group, there was a SCORAD change of -26.25% at week 12, while the Cyclosporine A group had a SCORAD change of -25.01%. Patients treated with IVIG (Intravenous Immunoglobulin) showed a -34.4% change in SCORAD percentage scores at week 4, which further decreased by 47.12% at week 24. Patients receiving 4mg of Baricitinib and TCS had a 52.5% rate of EASI-75 at 16 weeks, and patients receiving different doses of upadacitinib had a 63-75% rate of EASI-75 at 16 weeks. The rate of EASI-75 at 16 weeks was around 28% in patients who received various doses of Tralokinumab.The most common adverse events observed were nasopharyngitis, respiratory events and dermatitis atopic.

Conclusions and relevance

Awareness of adverse events and concomitant medications is crucial, and appropriate dosing and frequent laboratory and clinical monitoring are also essential. More real-world evidence and prospective cohort studies analyzing the effectiveness and safety of systemic therapies in children and adolescents are of paramount importance for optimizing personalized, effective, and safe management of the growing population of patients with atopic dermatitis in this age group.

Filaggrin loss-of-function variants are associated with atopic dermatitis phenotypes in a diverse, early-life prospective cohort

Loss-of-function (LoF) variants in the filaggrin (FLG) gene are the strongest known genetic risk factor for atopic dermatitis (AD), but the impact of these variants on AD outcomes is poorly understood. We comprehensively identified genetic variants through targeted region sequencing of FLG in children participating in the Mechanisms of Progression of Atopic Dermatitis to Asthma in Children cohort. Twenty FLG LoF variants were identified, including 1 novel variant and 9 variants not previously associated with AD. FLG LoF variants were found in the cohort. Among these children, the presence of 1 or more FLG LoF variants was associated with moderate/severe AD compared with those with mild AD. Children with FLG LoF variants had a higher SCORing for Atopic Dermatitis (SCORAD) and higher likelihood of food allergy within the first 2.5 years of life. LoF variants were associated with higher transepidermal water loss (TEWL) in both lesional and nonlesional skin. Collectively, our study identifies established and potentially novel AD-associated FLG LoF variants and associates FLG LoF variants with higher TEWL in lesional and nonlesional skin.

Microbiome modulators for atopic eczema: a systematic review of experimental and investigational therapeutics

INTRODUCTION

Atopic dermatitis (AD) is a common inflammatory cutaneous disease that arises due to dysregulation of the Th2 immune response, impaired skin barrier integrity, and dysbiosis of the skin and gut microbiota. An abundance of Staphylococcus aureus biofilms in AD lesions increases the Th2 immune response, and gut bacteria release breakdown products such as Short Chain Fatty Acids that regulate the systemic immune response.

AREAS COVERED

We aim to evaluate therapies that modulate the microbiome in humans and discuss the clinical implications of these treatments. We performed a review of the literature in which 2,673 records were screened, and describe the findings of 108 studies that were included after full-text review. All included studies discussed the effects of therapies on the human microbiome and AD severity. Oral probiotics, topical probiotics, biologics, and investigational therapies were included in our analysis.

EXPERT OPINION

Oral probiotics demonstrate mixed efficacy at relieving AD symptoms. Topical probiotics reduce S. aureus abundance in AD lesional skin, yet for moderate-severe disease, these therapies may not reduce AD severity scores to the standard of biologics. Dupilumab and tralokinumab target key inflammatory pathways in AD and modulate the skin microbiome, further improving disease severity.

Skin barrier-inflammatory pathway is a driver of the psoriasis-atopic dermatitis transition

As chronic inflammatory conditions driven by immune dysregulation are influenced by genetics and environment factors, psoriasis and atopic dermatitis (AD) have traditionally been considered to be distinct diseases characterized by different T cell responses. Psoriasis, associated with type 17 helper T (Th17)-mediated inflammation, presents as well-defined scaly plaques with minimal pruritus. AD, primarily linked to Th2-mediated inflammation, presents with poorly defined erythema, dry skin, and intense itching. However, psoriasis and AD may overlap or transition into one another spontaneously, independent of biological agent usage. Emerging evidence suggests that defects in skin barrier-related molecules interact with the polarization of T cells, which forms a skin barrier-inflammatory loop with them. This loop contributes to the chronicity of the primary disease or the transition between psoriasis and AD. This review aimed to elucidate the mechanisms underlying skin barrier defects in driving the overlap between psoriasis and AD. In this review, the importance of repairing the skin barrier was underscored, and the significance of tailoring biologic treatments based on individual immune status instead of solely adhering to the treatment guidelines for AD or psoriasis was emphasized.

N-benzyl-N-methyldecan-1-amine, derived from garlic, and its derivative alleviate 2,4-dinitrochlorobenzene-induced atopic dermatitis-like skin lesions in mice

Given the intricate etiology and pathogenesis of atopic dermatitis (AD), the complete cure of AD remains challenging. This study aimed to investigate if topically applying N-benzyl-N-methyldecan-1-amine (BMDA), derived from garlic, and its derivative [decyl-(4-methoxy-benzyl)-methyl-1-amine] (DMMA) could effectively alleviate AD-like skin lesions in 2,4-dinitrochlorobenzene (DNCB)-treated mice. Administering these compounds to the irritated skin of DNCB-treated mice significantly reduced swelling, rash, and excoriation severity, alongside a corresponding decrease in inflamed epidermis and dermis. Moreover, they inhibited spleen and lymph node enlargement and showed fewer infiltrated mast cells in the epidermis and dermis through toluidine-blue staining. Additionally, they led to a lower IgE titer in mouse sera as determined by ELISA, compared to vehicle treatment. Analyzing skin tissue from the mice revealed decreased transcript levels of inflammatory cytokines (TNF-α, IL-1β, and IL-6), IL-4, iNOS, and COX-2, compared to control mice. Simultaneously, the compounds impeded the activation of inflammation-related signaling molecules such as JNK, p38 MAPK, and NF-κB in the mouse skin. In summary, these findings suggest that BMDA and DMMA hold the potential to be developed as a novel treatment for healing inflammatory AD.

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.

A critical evaluation of suitability of tralokinumab for treatment of moderate-to-severe atopic dermatitis in adolescents and adults

INTRODUCTION

Atopic dermatitis (AD) is a chronic, intensely pruritic disease associated with significant patient burden. Recent advancements in AD pathogenesis have expanded its therapeutics pipeline. Tralokinumab is a fully human monoclonal antibody that binds specifically Interleukin (IL)-13, inhibiting the downstream IL-13 signaling. Phase 3 clinical trials and some real-world studies showed that tralokinumab, as monotherapy or in combination with topical corticosteroids, is efficacious and safe in adult patients with moderate-to-severe AD. Similar results were reported in a phase 3 trial in adolescents (aged ≥12 years).

AREAS COVERED

We review the role of IL-13 in AD and discuss the value of tralokinumab for treating moderate-to-severe AD, comparing efficacy and safety results derived from clinical trials and real-life data.

EXPERT OPINION

The role of IL-13 in AD supports a targeted therapeutic approach. Tralokinumab has proven efficacious and well-tolerated in a large proportion of patients confirming its value for treating moderate-to-severe AD from age 12 years onwards; it quickly improves itching and can maintain a high-level of response over time; it can be administered with flexible dosing schedules. Future studies will further clarify the role of IL-13 pathway and which patients would be best suited to tralokinumab, shifting AD treatment into an era of precision medicine.

Tralokinumab Provides Clinically Meaningful Responses at Week 16 in Adults with Moderate-to-Severe Atopic Dermatitis Who Do Not Achieve IGA 0/1

BACKGROUND AND OBJECTIVE

Investigator's Global Assessment of clear/almost clear skin (IGA 0/1) is a difficult endpoint to achieve after short-term treatment of chronic moderate-to-severe atopic dermatitis, and does not fully reflect clinically meaningful changes in other parameters. We assessed the impact of tralokinumab versus placebo on other clinically meaningful parameters in patients not achieving IGA 0/1 at week 16 using pooled data from two monotherapy phase III trials, ECZTRA 1 and 2.

METHODS

This post hoc analysis included patients (n = 1328) from ECZTRA 1 and 2 who did not achieve the co-primary endpoint, IGA 0/1 at week 16 without rescue medication. Endpoints evaluating atopic dermatitis extent and severity included proportions of patients achieving IGA 0/1, 50%, 75%, and 90% improvement in Eczema Area and Severity Index (EASI-50/75/90); endpoints evaluating patient-reported outcomes included a ≥ 3-point improvement in worst daily pruritus Numerical Rating Scale (NRS), a ≥ 3-point improvement in eczema-related sleep interference (sleep) NRS, a ≥ 4-point improvement in Dermatology Life Quality Index (DLQI), and DLQI ≤ 5. Specifically, clinically meaningful responses were defined as EASI-50, a ≥ 3-point improvement in itch NRS, or a ≥ 4-point improvement in DLQI at week 16.

RESULTS

Among ECZTRA 1 and 2 patients who did not achieve IGA 0/1 at week 16 without rescue medication, a significantly greater proportion of patients receiving tralokinumab versus placebo achieved EASI-50 (33.0% vs 13.0%), a ≥ 3-point improvement in itch NRS (22.6% vs 9.4%), or a ≥ 4-point improvement in DLQI (41.2% vs 24.5%) at week 16. In addition, compared with placebo, a numerically greater proportion of tralokinumab-treated patients achieved all three measures of clinically meaningful response (30% vs 18%) or a clinically meaningful change in at least one outcome (48.8% vs 28.5%). Significantly greater proportions of patients receiving tralokinumab versus placebo achieved additional clinician-reported and patient-reported outcomes, such as EASI-75 (13.5% vs 4.1%), EASI-90 (3.5% vs 1.1%), DLQI ≤ 5 (22.5% vs 12.5%), and a ≥ 3-point improvement in sleep NRS (24.5% vs 11.5%).

CONCLUSIONS

Tralokinumab provided clinically meaningful responses in patients with moderate-to-severe atopic dermatitis who did not achieve IGA 0/1 at week 16 and/or used rescue medication. Using multiple validated outcome measures of both efficacy and quality of life, alongside IGA scores, can better characterize tralokinumab treatment responses in patients with moderate-to-severe atopic dermatitis. [Video abstract available] CLINICAL TRIAL REGISTRATION: NCT03131648 (ECZTRA 1); study start date: 30 May, 2017; primary completion date: 7 August, 2018; study completion date: 10 October, 2019. NCT03160885 (ECZTRA 2); study start date: 12 June, 2017; primary completion date: 4 September, 2019; study completion date: 14 August, 2019. Video abstract: Tralokinumab provides clinically meaningful responses at week 16 in adults with moderate-to-severe atopic dermatitis who do not achieve IGA 0/1 (MP4 362818 KB).

Fine-mapping causal tissues and genes at disease-associated loci

Heritable diseases often manifest in a highly tissue-specific manner, with different disease loci mediated by genes in distinct tissues or cell types. We propose Tissue-Gene Fine-Mapping (TGFM), a fine-mapping method that infers the posterior probability (PIP) for each gene-tissue pair to mediate a disease locus by analyzing GWAS summary statistics (and in-sample LD) and leveraging eQTL data from diverse tissues to build cis-predicted expression models; TGFM also assigns PIPs to causal variants that are not mediated by gene expression in assayed genes and tissues. TGFM accounts for both co-regulation across genes and tissues and LD between SNPs (generalizing existing fine-mapping methods), and incorporates genome-wide estimates of each tissue's contribution to disease as tissue-level priors. TGFM was well-calibrated and moderately well-powered in simulations; unlike previous methods, TGFM was able to attain correct calibration by modeling uncertainty in cis-predicted expression models. We applied TGFM to 45 UK Biobank diseases/traits (average N = 316 K ) using eQTL data from 38 GTEx tissues. TGFM identified an average of 147 PIP > 0.5 causal genetic elements per disease/trait, of which 11% were gene-tissue pairs. Implicated gene-tissue pairs were concentrated in known disease-critical tissues, and causal genes were strongly enriched in disease-relevant gene sets. Causal gene-tissue pairs identified by TGFM recapitulated known biology (e.g., TPO-thyroid for Hypothyroidism), but also included biologically plausible novel findings (e.g., SLC20A2-artery aorta for Diastolic blood pressure). Further application of TGFM to single-cell eQTL data from 9 cell types in peripheral blood mononuclear cells (PBMC), analyzed jointly with GTEx tissues, identified 30 additional causal gene-PBMC cell type pairs at PIP > 0.5-primarily for autoimmune disease and blood cell traits, including the well-established role of CTLA4 in CD8+ T cells for All autoimmune disease. In conclusion, TGFM is a robust and powerful method for fine-mapping causal tissues and genes at disease-associated loci.

Tralokinumab Efficacy Over 1 Year in Adults with Moderate-to-Severe Atopic Dermatitis: Pooled Data from Two Phase III Trials

BACKGROUND

Two phase III trials, ECZTRA 1 and 2, confirmed the efficacy and safety of tralokinumab versus placebo in adults with moderate-to-severe atopic dermatitis (AD). To further explore the long-term efficacy of tralokinumab for AD, a pooled analysis of these trials was conducted.

METHODS

ECZTRA 1 and 2 patients (n = 1596 total) were randomized to tralokinumab 300 mg or placebo every 2 weeks (q2w) over 16 weeks. Patients achieving Investigator's Global Assessment of clear/almost clear skin (IGA 0/1) and/or 75% improvement in the Eczema Area and Severity Index (EASI-75) at Week 16, were re-randomized to tralokinumab q2w, every 4 weeks (q4w), or placebo (tralokinumab withdrawal) for another 36 weeks. Patients not achieving the response criteria at Week 16 received open-label tralokinumab q2w plus optional topical corticosteroids (TCS). A pooled, prespecified analysis assessed the proportions of Week 16 responders that maintained IGA 0/1 and/or EASI-75 at Week 52. Pooled data from all patients initiated with tralokinumab, regardless of the response at Week 16 or dosing regimen received thereafter, were analyzed post hoc.

RESULTS

In patients who achieved the primary endpoints at Week 16, IGA 0/1 responses were maintained at Week 52 without rescue treatment (including TCS) by 55.9%, 42.4%, and 34.0% of patients re-randomized to tralokinumab q2w, q4w, or placebo (tralokinumab withdrawal), respectively, while EASI-75 responses were maintained by 57.3%, 50.4%, and 26.4%, respectively (prespecified analysis). In a post hoc analysis of all patients initiated with tralokinumab, response rates improved over time with continued tralokinumab treatment beyond Week 16 to Week 52 for EASI-50 (63.1-82.7%), EASI-75 (37.6-61.8%), EASI-90 (20.4-37.3%), and IGA 0/1 (23.0-36.2%).

CONCLUSIONS

Tralokinumab treatment provides progressive and sustained improvement over 1 year in the extent and severity of AD in patients with moderate-to-severe AD.

CLINICAL TRIAL REGISTRATION

NCT03131648 (ECZTRA 1); study start date: 30 May 2017; primary completion date: 7 August 2018; study completion date: 10 October 2019. NCT03160885 (ECZTRA 2); study start date: 12 June 2017; primary completion date: 4 September 2019; study completion date: 14 August 2019. INFOGRAPHIC.

The role of tralokinumab in the treatment of atopic dermatitis and future perspectives for adolescents

Atopic dermatitis (AD) is an inflammatory skin disease that frequently occurs in adolescents. Although there are many treatment options, the challenge for clinicians is finding an effective long-term drug for AD with a favorable safety profile. The purpose of this review is to describe the role of tralokinumab, an IL-13 inhibitor, in treating adolescent AD. The clinical efficacy and safety of tralokinumab were established in clinical trials for adults with moderate-to-severe AD. Based on the results of these trials and the preliminary results of trials conducted on adolescents with AD, tralokinumab effectively alleviates symptoms with tolerable adverse effects. Extending the use of tralokinumab to adolescents with moderate-to-severe AD seems promising for the future.

Tralokinumab therapy for moderate-to-severe atopic dermatitis: Clinical outcomes with targeted IL-13 inhibition

Atopic dermatitis (AD) is a chronic, inflammatory, intensely pruritic skin disorder associated with significant patient burden. Interleukin (IL)-13 is a cytokine that acts as a driver of immune dysregulation, skin-barrier dysfunction, and microbiome dysbiosis that characterizes AD, and is consistently overexpressed in AD skin. Tralokinumab is a fully human immunoglobulin (Ig) G4 monoclonal antibody that binds specifically to IL-13 with high affinity, thereby inhibiting subsequent downstream IL-13 signaling. Three pivotal phase 3 clinical trials demonstrated that tralokinumab 300 mg every other week, as monotherapy or in combination with topical corticosteroids as needed, provides significant improvements in signs and symptoms of moderate-to-severe AD, as measured by Investigator's Global Assessment 0/1 (clear/almost clear) and Eczema Area and Severity Index-75 at Week 16. Improvements were observed soon after tralokinumab initiation and were maintained over 52 weeks of therapy. Tralokinumab significantly improved patient-reported outcomes such as itch and sleep, and demonstrated a safety profile comparable with placebo; conjunctivitis during tralokinumab therapy was generally mild. Similar results were observed in a phase 3 adolescent trial. The role of IL-13 in the pathophysiology of AD justifies a targeted approach and a wealth of clinical data supports tralokinumab as a new therapeutic option for people with moderate-to-severe AD.

Critical role of epigenetic modification in the pathogenesis of atopic dermatitis

Atopic dermatitis is a chronic inflammatory skin disease characterised by recurrent eczema-like lesions and severe pruritus, along with drying and decrustation of skin. Current research relates the pathogenesis of atopic dermatitis mainly to genetic susceptibility, abnormal skin barrier function, immune disorders, Staphylococcus aureus colonisation, microbiological dysfunction and vitamin D insufficiency. Epigenetic modifications are distinct genetic phenotypes resulting from environment-driven changes in chromosome functions in the absence of nuclear DNA sequence variation. Classic epigenetic events include DNA methylation, histone protein modifications and non-coding RNA regulation. Increasing evidence has indicated that epigenetic events are involved in the pathogenesis of atopic dermatitis by their effects on multiple signalling pathways which in turn influence the above factors. This review primarily analyses the function of epigenetic regulation in the pathogenesis of atopic dermatitis. In addition, it tries to make recommendations for personalised epigenetic treatment strategies for atopic dermatitis in the future.

Advanced In Vitro Three-Dimensional Skin Models of Atopic Dermatitis

Atopic dermatitis (AD) is one of the most prevalent inflammatory skin diseases that is characterized by eczematous rashes, intense itching, dry skin, and sensitive skin. Although AD significantly impacts the quality of life and the number of patients keeps increasing, its pathological mechanism is still unknown because of its complexity. The importance of developing new in vitro three-dimensional (3D) models has been underlined in order to understand the mechanisms for the development of therapeutics since the limitations of 2D models or animal models have been repeatedly reported. Thus, the new in vitro AD models should not only be created in 3D structure, but also reflect the pathological characteristics of AD, which are known to be associated with Th2-mediated inflammatory responses, epidermal barrier disruption, increased dermal T-cell infiltration, filaggrin down-regulation, or microbial imbalance. In this review, we introduce various types of in vitro skin models including 3D culture methods, skin-on-a-chips, and skin organoids, as well as their applications to AD modeling for drug screening and mechanistic studies.

The hidden sentinel of the skin: An overview on the role of interleukin-13 in atopic dermatitis

Recent evidence suggests that interleukin (IL)-13 is a crucial cytokine involved in the pathogenesis of atopic dermatitis (AD). It is a central driver of type-2 T-helper inflammation and is overexpressed in lesional skin of AD patients. Upon release in peripheral skin, IL-13 activates its receptors, recruits inflammatory cells, and modifies the skin microbiome. IL-13 also reduces the expression of epidermal barrier proteins and activates sensory nerve mediating the itch transmission signal. Novel therapeutics that target IL-13 seem to be efficacious and safe for the treatment of patients with moderate-to-severe AD. The aim of our manuscript is to review the role that IL-13 plays in AD immunopathogenesis.

Targeting Interleukin 13 for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a common chronic inflammatory skin condition that has a significant impact on a patient's quality of life and requires ongoing management. Conventional topical and systemic therapies do not target specific components of AD pathogenesis and, therefore, have limited efficacy and may be associated with long-term toxicity. Thus, AD management is challenging, with a significant proportion of patients not achieving clear skin or a reduction in pruritus. There remains a large unmet need for effective therapeutic strategies with favorable safety profiles that can be used long-term in patients with refractory AD. The emergence of targeted biological and small molecule therapies has effectively broadened available treatment options for moderate-to-severe AD. Most recently, interleukin 13 (IL-13) inhibitors were shown to be efficacious and well-tolerated, with tralokinumab already approved for use in this patient population. It is important for dermatologists to be aware of the evidence behind this emerging class of biologic agents to guide treatment choices and improve outcomes in patients with AD. The main objective of this paper is to review the current literature regarding the efficacy and safety of current and emerging anti-IL-13 monoclonal antibodies, including tralokinumab, lebrikizumab, cendakimab, and eblasakimab, for the treatment of moderate-to-severe AD.

Oral Janus kinase inhibitors for atopic dermatitis

Atopic dermatitis (AD) is one of the most common inflammatory skin conditions. The pathogenesis of AD involves skin barrier disruption and immune activation of T-helper (T_H)2 and T_H22 and varying degrees of T_H1 and T_H17 activation in various patient subtypes. Although AD is mainly driven by T_H2, the molecular and clinical heterogeneity of AD underscores the need for more efficacious treatments that target multiple immune axes. Janus kinase (JAK) inhibitors are novel therapeutics that broadly block many AD-related proinflammatory cytokines (interleukin [IL]-4, IL-5, IL-13, IL-31, thymic stromal lymphopoietin, interferon gamma, IL-12, IL-23, IL-17) across different immune pathways. Oral JAK inhibitors have been found to be efficacious in AD, with 2 (abrocitinib and upadacitinib) recently gaining US Food and Drug Administration approval and several others under investigation in clinical trials with promising results. These systemic agents have surpassed conventional thresholds of treatment response, with many patients achieving complete or almost complete skin clearance, and provide a fast-acting alternative therapy for patients who are not responsive to biologics or other conventional therapies. However, systemic JAK inhibitors come with health concerns, requiring additional long-term clinical trials to characterize their safety profile in patients with AD. This review summarizes the current literature on the safety and efficacy of oral JAK inhibitors in AD and discusses future directions for research.

Interleukin-13 and its receptor are synaptic proteins involved in plasticity and neuroprotection

Immune system molecules are expressed by neurons, yet their functions are often unknown. We have identified IL-13 and its receptor IL-13Ra1 as neuronal, synaptic proteins in mouse, rat, and human brains, whose engagement upregulates the phosphorylation of NMDAR and AMPAR subunits and, in turn, increases synaptic activity and CREB-mediated transcription. We demonstrate that increased IL-13 is a hallmark of traumatic brain injury (TBI) in male mice as well as in two distinct cohorts of human patients. We also provide evidence that IL-13 upregulation protects neurons from excitotoxic death. We show IL-13 upregulation occurring in several cohorts of human brain samples and in cerebrospinal fluid (CSF). Thus, IL-13 is a physiological modulator of synaptic physiology of neuronal origin, with implications for the establishment of synaptic plasticity and the survival of neurons under injury conditions. Furthermore, we suggest that the neuroprotection afforded through the upregulation of IL-13 represents an entry point for interventions in the pathophysiology of TBI.

Twist1 as a target for prevention of cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (cSCC) represents an important clinical problem requiring novel approaches for both prevention and treatment. The transcription factor, Twist-related protein 1 (Twist1), has been identified as having a key mechanistic role in the development and progression of cSCC. Studies in relevant mouse models of cSCC have shown that Twist1 regulates epithelial-mesenchymal transition (EMT) and stemness driving progression and metastasis of cSCC. In addition, further research has shown that Twist1 regulates the balance between keratinocyte proliferation and differentiation and therefore impacts earlier stages of cSCC development. Through use of keratinocyte specific Twist1 knockout models, a role for this gene in keratinocyte stem cell homeostasis has been revealed. As a transcription factor, Twist1 regulates a large number of genes both in a positive, as well as a negative manner across several interdependent pathways. Studies in keratinocyte specific knockout models have shown that Twist1 upregulates the expression of genes involved in proliferation, stemness, and EMT while downregulating the expression of genes associated with differentiation. Furthermore, a number of compounds, including naturally occurring compounds, have been identified that target Twist1 and can block its effects in cancer cells and in keratinocytes in vivo. Collectively, the current understanding of Twist1 function in cSCC development and progression suggests that it represents a potential target for prevention and treatment of cSCC.

Efficacy and Safety of Upadacitinib for Management of Moderate-to-Severe Atopic Dermatitis: An Evidence-Based Review

Atopic dermatitis (AD) is a common skin condition characterized by inflammation that presents with erythematous and pruritic skin. Its chronic relapse-remitting nature has a significant impact on the quality of life, and often requires ongoing management. Given the limited treatments available for AD, there remains a large need for effective and safe alternative therapies for long-term use. Janus kinase (JAK) inhibitors are a new class of agents that target the JAK-STAT pathway, which plays an important role in the production of proinflammatory cytokines involved in AD pathogenesis. Phase II and III clinical trials revealed that JAK inhibitors, such as upadacitinib, are effective and well-tolerated agents for the treatment of moderate-to-severe AD. As a result, upadacitinib was approved for use in patients with moderate-to-severe AD by the European Medicines Agency (2021), Health Canada (2021) and the FDA (2022) in the last year. It is important for dermatologists to be aware of the clinical evidence to continue incorporating the use of upadacitinib into the treatment algorithm for AD, which will ultimately lead to improved patient outcomes. Therefore, this review is an up-to-date summary of the clinical data available on the efficacy and safety of upadacitinib treatment for AD.

Galactomyces Ferment Filtrate Potentiates an Anti-Inflammaging System in Keratinocytes

Skincare products play a crucial role in preventing the dry skin induced by various causes. Certain ingredients can help to improve the efficacy of skincare products. Galactomyces ferment filtrate (GFF) is such a functional ingredient. Its use originated from the empirical observation that the hands of sake brewers who deal with yeast fermentation retain a beautiful and youthful appearance. Consequently, skincare products based on GFF are widely used throughout the world. Recent studies have demonstrated that GFF activates an aryl hydrocarbon receptor (AHR) and upregulates the expression of filaggrin, a pivotal endogenous source of natural moisturizing factors, in epidermal keratinocytes. It also activates nuclear factor erythroid-2-related factor 2 (NRF2), the antioxidative master transcription factor, and exhibits potent antioxidative activity against oxidative stress induced by ultraviolet irradiation and proinflammatory cytokines, which also accelerate inflammaging. GFF-mediated NRF2 activation downregulates the expression of CDKN2A, which is known to be overexpressed in senescent keratinocytes. Moreover, GFF enhances epidermal terminal differentiation by upregulating the expression of caspase-14, claudin-1, and claudin-4. It also promotes the synthesis of the antiinflammatory cytokine IL-37 and downregulates the expression of proallergic cytokine IL-33 in keratinocytes. In addition, GFF downregulates the expression of the CXCL14 and IL6R genes, which are involved in inflammaging. These beneficial properties might underpin the potent barrier-protecting and anti-inflammaging effects of GFF-containing skin formulae.

Allergen-specific immunotherapy induces monocyte-derived dendritic cells but attenuates their maturation and cytokine production in the lesional skin of an atopic dermatitis mouse model

Atopic dermatitis (AD) is a common inflammatory skin disease, but current treatments for AD are mostly limited to the alleviation of symptoms and inhibition of inflammation. Allergen-specific immunotherapy (ASIT) is the only curative approach for allergic diseases and could be a promising way to cure AD. Although ASIT has been gradually applied to patients with AD, there are still few studies on its efficacy evaluation and mechanisms. Based on our previous established AD mouse model by dinitrofluorobenzene and an extract of Dermatophagoides farina, we performed ASIT on this AD model through subcutaneous injection of Dermatophagoides farina extracts to evaluate the efficacy of ASIT and study its underlying mechanisms. Our results showed that ASIT could not only alleviate skin lesions and scratching behaviors of AD mice but also inhibit their Th2-type immune responses. Furthermore, ASIT could increase the infiltration of monocyte-derived dendritic cells in skin lesions but attenuated their maturation and production of interleukin 1α and interleukin 12/23 p40. As immature and semi-mature dendritic cells preferentially induce tolerance, accumulation but inhibition of maturation of monocyte-derived dendritic cells after ASIT may indicate a novel mechanism of ASIT and a potential therapeutic target for AD.

Immunotherapy in atopic dermatitis

In the past decade, the emergence of biologics targeting human cytokine networks has advanced a new era in atopic dermatitis therapy. Dupilumab, in particular, the most widely studied and used IL-4/IL-13 inhibitor, has been considered a milestone in the treatment of patients with moderate-to-severe atopic dermatitis. In addition to the IL-4 and IL-13 pathways, many other cytokines and receptors have been newly targeted as therapeutic options. In this review, the authors provide an overview of the approved and tested biologics and JAK inhibitors for the treatment of atopic dermatitis, including their advantages and limitations.

Potential Therapeutic Skin Microbiomes Suppressing Staphylococcus aureus-Derived Immune Responses and Upregulating Skin Barrier Function-Related Genes via the AhR Signaling Pathway

Disruption of the skin microbial balance can exacerbate certain skin diseases and affect prognosis and treatment. Changes in the distribution and prevalence of certain microbial species on the skin, such as Staphylococcus aureus (SA), can impact the development of severe atopic dermatitis (AD) or psoriasis (Pso). A dysfunctional skin barrier develops in AD and Pso due to SA colonization, resulting in keratinization and chronic or progressive chronic inflammation. Disruption of the skin barrier following SA colonization can elevate the production of T helper 2 (Th2)-derived cytokines, which can cause an imbalance in Th1, Th2, and Th17 cells. This study examined the ability of potential therapeutic skin microbiomes, such as Cutibacterium avidum R-CH3 and Staphylococcus hominis R9, to inhibit SA biofilm formation and restore skin barrier function-related genes through the activation of the aryl hydrocarbon receptor (AhR) and the nuclear factor erythroid-2-related factor 2 (Nrf2) downstream target. We observed that IL-4/IL-13-induced downregulation of FLG, LOR, and IVL induced by SA colonization could be reversed by dual AhR/Nrf2 activation. Further, OVOL1 expression may be modulated by functional microbiomes via dual AhR/Nrf2 activation. Our results suggest that our potential therapeutic skin microbiomes can prevent SA-derived Th2-biased skin barrier disruption via IL-13 and IL-4-dependent FLG deregulation, STAT3 activation, and AhR-mediated STAT6 expression.

An Atopic Dermatitis-Like Mouse Model by Alternate Epicutaneous Application of Dinitrofluorobenzene and an Extract of Dermatophagoides Farinae

Several studies have tried to establish mice models of atopic dermatitis (AD) through the allergen of Dermatophagoides farinae (Df). However, there are no typical skin lesions after epicutaneous application of an extract of Df (DfE) on BALB/c mice. Dinitrofluorobenzene (DNFB) is a common hapten that brings about contact dermatitis. Skin dysfunction induced by DNFB may be a way to enhance the effects of DfE on mice skin. Thus, we hypothesized that alternate epicutaneous application of DNFB and DfE could induce AD-like skin lesions on BALB/c mice. To test this hypothesis, we alternately applied the DNFB and DfE to the back skin of BALB/c mice for 8 weeks. Changes in mice skin lesions and the frequency of scratching behavior were recorded. The variation of Th1-related cytokines (interferon-γ [IFN-γ] and interleukin two [IL-2]) and Th2-related cytokines (IL-4 and IL-13) was detected in serum and lesional skin. Eventually, the BALB/c mice developed severe erythema, erosion, scarring, and excoriation on the entire back, showing a high frequency of scratching behavior. In addition, Th2 cells' dominant cytokines appeared in both serum and lesional skin. Those results indicate that alternating epicutaneous exposure to DNFB and DfE can produce AD-like models with typical clinical features and Th2-type immune responses in BALB/c mice. This model could be valuable for studying the pathogenesis of AD and developing novel therapeutic agents for it.

Immune system changes in those with hypertension when infected with SARS-CoV-2

The coronavirus disease 2019 (COVID-19) outbreak has become an evolving global health crisis. With an increasing incidence of primary hypertension, there is greater awareness of the relationship between primary hypertension and the immune system [including CD4+, CD8+ T cells, interleukin-17 (IL-17)/T regulatory cells (Treg) balance, macrophages, natural killer (NK) cells, neutrophils, B cells, and cytokines]. Hypertension is associated with an increased risk of various infections, post-infection complications, and increased mortality from severe infections. Despite ongoing reports on the epidemiological and clinical features of COVID-19, no articles have systematically addressed the role of primary hypertension in COVID-19 or how COVID-19 affects hypertension or specific treatment in these high-risk groups. Here, we synthesize recent advances in understanding the relationship between primary hypertension and COVID-19 and its underlying mechanisms and provide specific treatment guidelines for these high-risk groups.

Safety and Efficacy of Nemolizumab for Atopic Dermatitis With Pruritus: A Systematic Review and Meta-Regression Analysis of Randomized Controlled Trials

Background

Nemolizumab is deemed as a promising drug for atopic dermatitis (AD) patients with pruritus.

Objective

This study aimed to evaluate the efficacy of nemolizumab in treating patients with AD and the association between the dosage or regimen of nemolizumab with the improvement in clinical indices.

Methods and Materials

PubMed, Embase, and the Cochrane Library were searched for randomized controlled trials (RCTs) published from inception to August 2021.

Results

A total of 14 cohorts of participants from six randomized controlled studies were included in the meta-analysis. Nemolizumab significantly reduced the pruritus VAS (WMD = -18.86, 95% CI: -27.57 to -10.15, p < 0.001; I ² = 56.2%, p _{heterogeneity} = 0.005) and EASI (WMD = -11.76, 95% CI: -20.55 to -2.96, p = 0.009; I ² = 0%, p _{heterogeneity} = 0.978) scores compared with placebo. No significant difference was observed in the occurrence of any AEs (RR = 1.03, 95% CI: 0.93 to 1.13, p = 0.593; I ² = 0%, p _{heterogeneity} = 0.980) between the two groups. The univariate meta-regression showed that both the dosage and study duration had no association with the change of pruritus VAS score.

Conclusion

Nemolizumab presented a promising effect based on the difference in the average change in pruritus VAS and EASI scores compared with placebo. The results indicated its efficacy in relieving pruritus and the severity of AD and improving patients' quality of life.

Epidermis-Intrinsic Transcription Factor Ovol1 Coordinately Regulates Barrier Maintenance and Neutrophil Accumulation in Psoriasis-Like Inflammation

Skin epidermis constitutes the exterior barrier that protects the body from dehydration and environmental assaults. Barrier defects underlie common inflammatory skin diseases, but the molecular mechanisms that maintain barrier integrity and regulate epidermal-immune cell cross-talk in inflamed skin are not fully understood. In this study, we show that skin epithelia-specific deletion of Ovol1, which encodes a skin disease‒linked transcriptional repressor, impairs the epidermal barrier and aggravates psoriasis-like skin inflammation in mice in part by enhancing neutrophil accumulation and abscess formation. Through molecular studies, we identify IL-33, a cytokine with known pro-inflammatory and anti-inflammatory activities, and Cxcl1, a neutrophil-attracting chemokine, as potential weak and strong direct targets of Ovol1, respectively. Furthermore, we provide functional evidence that elevated Il33 expression reduces disease severity in imiquimod-treated Ovol1-deficient mice, whereas persistent accumulation and epidermal migration of neutrophils exacerbate it. Collectively, our study uncovers the importance of an epidermally expressed transcription factor that regulates both the integrity of the epidermal barrier and the behavior of neutrophils in psoriasis-like inflammation.

Atopic Dermatitis: The Fate of the Fat

Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease in which dry and itchy skin may develop into skin lesions. AD has a strong genetic component, as children from parents with AD have a two-fold increased chance of developing the disease. Genetic risk loci and epigenetic modifications reported in AD mainly locate to genes involved in the immune response and epidermal barrier function. However, AD pathogenesis cannot be fully explained by (epi)genetic factors since environmental triggers such as stress, pollution, microbiota, climate, and allergens also play a crucial role. Alterations of the epidermal barrier in AD, observed at all stages of the disease and which precede the development of overt skin inflammation, manifest as: dry skin; epidermal ultrastructural abnormalities, notably anomalies of the lamellar body cargo system; and abnormal epidermal lipid composition, including shorter fatty acid moieties in several lipid classes, such as ceramides and free fatty acids. Thus, a compelling question is whether AD is primarily a lipid disorder evolving into a chronic inflammatory disease due to genetic susceptibility loci in immunogenic genes. In this review, we focus on lipid abnormalities observed in the epidermis and blood of AD patients and evaluate their primary role in eliciting an inflammatory response.

Polyinosinic:polycytidylic acid aggravates calcipotriol-induced atopic dermatitis-like skin lesions in mice by increasing the expression of thymic stromal lymphopoietin

Background

Polyinosinic:polycytidylic acid [poly (I:C)] is a synthetic viral double-stranded RNA analog that can activate Toll-like receptor 3 (TLR3) and induce the release of thymic stromal lymphopoietin (TSLP). TSLP has been shown to contribute to atopic dermatitis (AD). This study explored the effects of poly (I:C) in a calcipotriol-induced model of murine AD.

Methods

Calcipotriol (MC903) was used to establish AD-like mice model. Mice in the MC903 + poly (I:C) group were then treated with poly (I:C) in a concentration of 5 µg/g bodyweight. The impact of poly (I:C) treatment on these animals was assessed based upon changes in lesions, bodyweight, ear thickness, and histopathological findings. In addition, serum interleukin 4 (IL-4), interferon-γ (IFN-γ), immunoglobulin E (IgE), IL-13, and TSLP levels were measured using enzyme-linked immunosorbent assay (ELISA), while tissue IL-13 and TSLP levels were assessed using ELISA, Western blotting, and immunohistochemical staining, and mast cell infiltration was assessed through toluidine blue (TBO) staining.

Results

Relative to vehicle control treatment, poly (I:C) administration was associated with a significant exacerbation of calcipotriol-induced AD-like murine skin lesions. In animals treated with poly (I:C), the levels of serum IL-4, IL-13 and TSLP increased significantly, while the level of IFN-γ did not change. It also increased IL-13 and TSLP levels in skin lesions relative to the control-group mice and increased dermal mast cell infiltration and IgE production.

Conclusions

These data indicate that poly (I:C) treatment and exogenous activation of TLR3 exacerbate murine calcipotriol-induced AD-like skin lesions in part by increasing the production of TSLP and other T-helper 2 (Th2)-related cytokines.

Keywords

Atopic dermatitis (AD); polyinosinic:polycytidylic acid [poly (I:C)]; thymic stromal lymphopoietin (TSLP); Toll-like receptor 3 (TLR3)

Overcoming drug delivery barriers and challenges in topical therapy of atopic dermatitis: A nanotechnological perspective

Atopic dermatitis (AD) is an inflammatory disorder centered around loss of epidermal barrier function, and T helper 2 (Th2) immune responses. The current understanding of disease heterogeneity and complexity, limits the rational use of existing topical, systemic therapeutic agents, but paves way for development of advanced therapeutic agents. Additionally, advanced nanocarriers that deliver therapeutics to target cells, seem to offer a promising strategy, to overcome intrinsic limitations and challenges of conventional, and traditional drug delivery systems. Ever-evolving understanding of molecular target sites and complex pathophysiology, adverse effects of current therapeutic options, inefficient disease recapitulation by existing animal models are some of the challenges that we face. Also, despite limited success in market translatibility, nanocarriers have demonstrated excellent preclinical results and have been extensively studied for AD. Detailed research on behavior of nanocarriers in different patients and tailored therapy to account for phenotypic variability of the disease are the new research avenues that we look forward to.

IL-12 regulates type 3 immunity through interfollicular keratinocytes in psoriasiform inflammation

[Figure: see text].

Systematic Review on the Efficacy and Safety of Oral Janus Kinase Inhibitors for the Treatment of Atopic Dermatitis

Background: Atopic dermatitis is a chronic, relapsing and remitting disease that can be difficult to treat despite a recently approved biologic therapy targeting IL-4/IL-13 receptor. Oral janus kinase inhibitors (JAKi) represent a novel therapeutic class of targeted therapy to treat moderate-to-severe atopic dermatitis (AD). Objective: To review the efficacy, safety, and pharmacokinetic characteristics of oral JAKi in the treatment of AD. Methods: A PRISMA systematic review was conducted using MEDLINE, EMBASE (Ovid), and PubMed databases for studies assessing the efficacy, safety, and/or pharmacokinetic properties of oral forms of JAKi in the treatment of AD in pediatric or adult populations from inception to June 2021. Results: 496 papers were reviewed. Of 28 articles that underwent full text screening, 11 met our inclusion criteria for final qualitative review. Four studies examined abrocitinib; three studies examined baricitinib; three examined upadacitinib and one examined gusacitinib (ASN002). Significant clinical efficacy and a reassuring safety profile was reported for all JAKi agents reviewed. Rapid symptom control was reported for abrocitinib, baricitinib and upadacitinib. Limitations: Given the relatively limited evidence for each JAKi and the differences in patient eligibility criteria between studies, the data was not deemed suitable for a meta-analysis at this time. Conclusion: Given their ability to achieve rapid symptom control with a reassuring safety profile, we recommend considering the use of JAKi as a reliable systemic treatment option for adult patients with moderate-to-severe AD, who are unresponsive to topical or skin directed treatments.

Interleukin (IL)-13/IL-22/IL-31 skewing within the skin-homing T-cell population in papuloerythroderma

Papuloerythroderma (PEO) is a representative form of senile erythroderma with an unclear pathogenesis. This study aimed to characterize the T-cell phenotypes responsible for the pathogenesis of PEO. Cytokine profiles and cutaneous lymphocyte antigen (CLA) expression on circulating T lymphocytes in patients with PEO were simultaneously analyzed using flow cytometry. The patients with PEO showed significantly higher circulating interleukin (IL)-4-, IL-13-, IL-22-, and IL-31-producing CD4+ and CD8+ T-cell levels than healthy subjects. However, their levels significantly decreased after remission of PEO. No difference was observed in the proportions of circulating interferon (IFN)-γ- and IL-17-producing CD4+ and CD8+ T cells between the patients with PEO and healthy subjects. In particular, the proportion of circulating IL-4-, IL-13-, IL-22-, and IL-31-producing CD4+ and CD8+ T cells was much higher in the CLA+ subset than in the CLA- subset. There was a positive correlation between IL-13-, IL-22-, and IL-31-producing CD4+ T cells and the disease severity score of PEO. Moreover, a positive correlation was also observed between the proportion of IL-22- or IL-31-producing cells and circulating IL-13-producing cells in both CD4+ and CD8+ T cells, and approximately 50% of both IL-22- and IL-31-producing CD4+ and CD8+ T cells coproduced IL-13. IL-13/IL-22/IL-31 skewing within the skin-homing T-cell population may be involved in the pathogenesis of PEO.

Tralokinumab for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a relapsing or chronic heterogeneous inflammatory skin disorder with a substantial economic and social impact. AD is a multifactorial disease regulated by a diverse set of environmental and genetic determinants. The main factors involved in the pathogenesis of AD are epidermal barrier dysfunction, immune dysregulation, and dysbiosis. Current data have valued interleukin (IL)-13 as conceivably the crucial cytokine in the underlying inflammation of AD. Advances in understanding AD pathophysiology have driven the progress of targeted immunomodulatory treatments for the treatment of AD, including tralokinumab, a selective IL-13 inhibitor. A phase IIb clinical trial showed that a dosing regimen of 150 or 300 mg every 2 weeks effectively treated moderate-to-severe AD in adults with an acceptable tolerability profile. Phase III clinical trials demonstrated that results with tralokinumab in monotherapy were superior to those with placebo at 16 weeks of treatment. It was also well tolerated up to 52 weeks in the vast majority of patients. In addition, in association with topical corticosteroids, tralokinumab was well tolerated and effective and had a favorable risk-benefit profile. These data provide additional evidence that IL-13 is central to AD pathogenesis, suggesting that tralokinumab may be seen as an innovative option for the treatment of moderate-to-severe AD.

Interactions Between Specific Immune Status of Pregnant Women and SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogen responsible for the Coronavirus Disease 2019 (COVID-19) global pandemic. Because it is a new and highly contagious coronavirus, most people, especially pregnant women, lack immunity. It is therefore important to understand the interaction between why pregnant women are susceptible to SARS-CoV-2 and the specific immune systems of pregnant women. Here, we provide an overview of the changes that occur in the immune system during pregnancy, the activation and response of the immune system in pregnant women with COVID-19, adverse pregnancy outcomes in pregnant women with COVID-19, and the treatment and prevention of COVID-19 in this population.

The Implications of Pruritogens in the Pathogenesis of Atopic Dermatitis

Atopic dermatitis (AD) is a prototypic inflammatory disease that presents with intense itching. The pathophysiology of AD is multifactorial, involving environmental factors, genetic susceptibility, skin barrier function, and immune responses. A recent understanding of pruritus transmission provides more information about the role of pruritogens in the pathogenesis of AD. There is evidence that pruritogens are not only responsible for eliciting pruritus, but also interact with immune cells and act as inflammatory mediators, which exacerbate the severity of AD. In this review, we discuss the interaction between pruritogens and inflammatory molecules and summarize the targeted therapies for AD.

New Treatments for Atopic Dermatitis Targeting Skin Barrier Repair via the Regulation of FLG Expression

Atopic dermatitis (AD) is one of the most common chronic, inflammatory skin disorders with a complex etiology and a broad spectrum of clinical phenotypes. Despite its high prevalence and effect on the quality of life, safe and effective systemic therapies approved for long-term management of AD are limited. A better understanding of the pathogenesis of atopic dermatitis in recent years has contributed to the development of new therapeutic approaches that target specific pathophysiological pathways. Skin barrier dysfunction and immunological abnormalities are critical in the pathogenesis of AD. Recently, the importance of the downregulation of epidermal differentiation complex (EDC) molecules caused by external and internal stimuli has been extensively emphasized. The purpose of this review is to discuss the innovations in the therapy of atopic dermatitis, including biologics, small molecule therapies, and other drugs by highlighting regulatory mechanisms of skin barrier-related molecules, such as filaggrin (FLG) as a crucial pathway implicated in AD pathogenesis.

OVOL1 Regulates Psoriasis-Like Skin Inflammation and Epidermal Hyperplasia

Psoriasis is a common inflammatory skin disease characterized by aberrant inflammation and epidermal hyperplasia. Molecular mechanisms that regulate psoriasis-like skin inflammation remain to be fully understood. Here, we show that the expression of Ovol1 (encoding ovo-like 1 transcription factor) is upregulated in psoriatic skin, and its deletion results in aggravated psoriasis-like skin symptoms following stimulation with imiquimod. Using bulk and single-cell RNA sequencing, we identify molecular changes in the epidermal, fibroblast, and immune cells of Ovol1-deficient skin that reflect an altered course of epidermal differentiation and enhanced inflammatory responses. Furthermore, we provide evidence for excessive full-length IL-1α signaling in the microenvironment of imiquimod-treated Ovol1-deficient skin that functionally contributes to immune cell infiltration and epidermal hyperplasia. Collectively, our study uncovers a protective role for OVOL1 in curtailing psoriasis-like inflammation and the associated skin pathology.

Potential effect of fish oil to preserve expression of cell cycle and tight junction regulating genes in colon after di-isononyl phthalate ingestion in albino Wistar rats

Di-isononyl phthalate (DIP) is considered a high molecular-weight subtype of phthalates that are commonly used and could easily affect the gastrointestinal tract (GIT). Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the main active components of fish oil (FO), and their anti-inflammatory potential was previously documented. The current study was designed to investigate the protective potential of fish oil against the impacts of DIP exposure on the colon of albino Wistar rats. Sixty albino Wistar rats were divided into Control group received corn oil for ten days. Di-isononyl phthalate treated group received DIP. Di-isononyl phthalate + fish oil treated group received both DIP and FO. FO was found to preserve the histological architecture, tight junction and cell cycle of the colon. In conclusion, the current study provided an evidence that FO has a protective potential against DIP further examinations to be done to fully understand the molecular basis of this potential as a step for further clinical applications.

New and Emerging Systemic Treatments for Atopic Dermatitis

Atopic dermatitis (AD) is a prevalent inflammatory skin condition that, depending on its severity, can cause enormous morbidity. Corticosteroids and systemic immunosuppression, traditionally standard of care for difficult-to-treat disease, have many undesirable side effects. The desire for targeted treatments along with an improved understanding of the pathophysiology of AD has spurred the development of novel treatments. In this article, we review promising new treatments and discuss how their targets—IL-13, IL-31, OX40 (CD134), and the Janus kinase family of proteins—participate in the pathogenesis of AD. We review the published phase II and III data for dupilumab, tralokinumab, lebrikizumab, nemolizumab, anti-OX40 antibody, baricitinib, abrocitinib, and upadacitinib. The introduction of new agents may offer new options, but it remains to be seen how narrow-acting agents, like single interleukin inhibitors, will compare in safety and efficacy to broad-acting agents such as JAK inhibitors.

EAACI Biologicals Guidelines-dupilumab for children and adults with moderate-to-severe atopic dermatitis

Atopic dermatitis imposes a significant burden on patients, families and healthcare systems. Management is difficult, due to disease heterogeneity, co-morbidities, complexity in care pathways and differences between national or regional healthcare systems. Better understanding of the mechanisms has enabled a stratified approach to the management of atopic dermatitis, supporting the use of targeted treatments with biologicals. However, there are still many issues that require further clarification. These include the definition of response, strategies to enhance the responder rate, the duration of treatment and its regimen (in the clinic or home-based), its cost-effectiveness and long-term safety. The EAACI Guidelines on the use of dupilumab in atopic dermatitis follow the GRADE approach in formulating recommendations for each outcome and age group. In addition, future approaches and research priorities are discussed.

Selective IL-13 inhibitors for the treatment of atopic dermatitis

Background

Atopic dermatitis (AD) is one of the most common chronic inflammatory skin diseases worldwide. AD pathogenesis is multifactorial, involving environmental and genetic factors. IL-13 stands out as one of the main cytokines in the pathophysiology of AD. Currently, dupilumab, which targets both IL-4 and IL-13 signalling, is the only biologic agent approved for the treatment of moderate-to-severe AD. New targeted biologic therapies are being developed, such as lebrikizumab and tralokinumab, two selective IL-13 inhibitors. This article reviews the role of IL-13 in AD and the most recent data on lebrikizumab and tralokinumab.

Methods

A narrative review of the literature was written after retrieving relevant articles in the PubMed database (up until December 2020) using the following keywords present in the title, abstract or body: atopic dermatitis; interleukin 13; IL-13; tralokinumab; lebrikizumab, biologic therapy.

Discussion

A phase IIb trial showed that all three dosing regimens evaluated (lebrikizumab 125 mg every 4 weeks (Q4W), 250 mg Q4W or 250 mg every 2 weeks) achieved rapid and dose-dependent efficacy concerning the signs and symptoms of AD, with a statistically significant improvement, at week 16. Tralokinumab was studied in three phase III clinical trials and reached its primary endpoints at week 16 (ECZTRA 1 and 2 in monotherapy and ECZTRA 3 with concomitant topical corticosteroids), with response maintained over time. Both lebrikizumab and tralokinumab exhibited good safety profiles in AD trials, with adverse effects usually being comparable between the control and treatment groups.

Conclusion

The evidence supports the hypothesis that selective antagonism of IL-13 is sufficient to control AD, providing an improvement in the patient’s quality of life. Therefore, the development of lebrikizumab and tralokinumab represents a new and exciting phase in the management of AD.