Pathophysiology Of Atopic Dermatitis Research Articles

Abrocitinib-associated adverse events: a real-world pharmacovigilance study using the FAERS database

ABSTRACT Background Atopic dermatitis (AD) is a common chronic inflammatory skin disease. Janus kinase (JAK) modulates cytokines involved in AD pathophysiology, and JAK inhibitors have emerged as effective pharmacotherapeutic remedies for AD. Abrocitinib, an oral selective inhibitor of JAK1, is indicated for the management of moderate-to-severe AD. The current study evaluated the adverse events (AEs) associated with abrocitinib in a real-world setting. Methods To quantify the signals of abrocitinib-associated AEs, we used the US Food and Drug Administration Adverse Event Reporting System (FAERS) for this pharmacovigilance study with two established pharmacovigilance methods. Results A total of 1071 AEs of abrocitinib were investigated as the primary suspected from the FAERS to detect and characterize relevant safety signals. The analysis revealed 85 signals for abrocitinib. The most common AE for abrocitinib was drug ineffective. The signal strength of eczema herpeticum was 515.87 (277.80–957.98) and 510.59 (5148.65) and exhibited the highest strength for abrocitinib. Rare AEs such as aggravated condition, pruritus, and hypersensitivity were not listed on the label, and attention to these AEs is required. Conclusion The analysis of the AE signals may provide support for clinical monitoring and risk identification of abrocitinib.

Interplay of cytokines in the pathophysiology of atopic dermatitis: insights from Murin models and human.

The pathogenesis of atopic dermatitis (AD) is understood to be crucially influenced by three main factors: dysregulation of the immune response, barrier dysfunction, and pruritus. In the lesional skin of AD, various innate immune cells, including Th2 cells, type 2 innate lymphoid cells (ILC2s), and basophils, produce Th2 cytokines [interleukin (IL)-4, IL-5, IL-13, IL-31]. Alarmins such as TSLP, IL-25, and IL-33 are also produced by epidermal keratinocytes, amplifying type 2 inflammation. In the chronic phase, not only Th2 cells but also Th22 and Th17 cells increase in number, leading to suppression of filaggrin expression by IL-4, IL-13, and IL-22, which further deteriorates the epidermal barrier function. Dupilumab, which targets IL-4 and IL-13, has shown efficacy in treating moderate to severe AD. Nemolizumab, targeting IL-31RA, effectively reduces pruritus in AD patients. In addition, clinical trials with fezakinumab, targeting IL-22, have demonstrated promising results, particularly in severe AD cases. Conversely, in murine models of AD, several cytokines, initially regarded as promising therapeutic targets, have not demonstrated sufficient efficacy in clinical trials. IL-33 has been identified as a potent activator of immune cells, exacerbating AD in murine models and correlating with disease severity in human patients. However, treatments targeting IL-33 have not shown sufficient efficacy in clinical trials. Similarly, thymic stromal lymphopoietin (TSLP), integral to type 2 immune responses, induces dermatitis in animal models and is elevated in human AD, yet clinical treatments like tezepelumab exhibit limited efficacy. Therapies targeting IL-1α, IL-5, and IL-17 also failed to achieve sufficient efficacy in clinical trials. It has become clear that for treating AD, IL-4, IL-13, and IL-31 are relevant therapeutic targets during the acute phase, while IL-22 emerges as a target in more severe cases. This delineation underscores the necessity of considering distinct pathophysiological aspects and therapeutic targets in AD between mouse models and humans. Consequently, this review delineates the distinct roles of cytokines in the pathogenesis of AD, juxtaposing their significance in human AD from clinical trials against insights gleaned from AD mouse models. This approach will improve our understanding of interspecies variation and facilitate a deeper insight into the pathogenesis of AD in humans.

Unraveling Atopic Dermatitis: Insights into Pathophysiology, Therapeutic Advances, and Future Perspectives.

Atopic dermatitis (AD) is an inflammatory skin condition that frequently develops before the onset of allergic rhinitis or asthma. More than 10% of children are affected by this serious skin condition, which is painful for the sufferers. Recent research has connected the environment, genetics, the skin barrier, drugs, psychological factors, and the immune system to the onset and severity of AD. The causes and consequences of AD and its cellular and molecular origins are reviewed in this paper. The exploration of interleukins and their influence on the immunological pathway in AD has been facilitated by using relevant biomarkers in clinical trials. This approach enables the identification of novel therapeutic modalities, fostering the potential for targeted translational research within the realm of personalized medicine. This review focuses on AD's pathophysiology and the ever-changing therapeutic landscape. Beyond the plethora of biologic medications in various stages of approval or development, a range of non-biologic targeted therapies, specifically small molecules, have emerged. These include Janus kinase (JAK) inhibitors like Baricitinib, Upadacitinib, and Abrocitinib, thus expanding the spectrum of therapeutic options. This review also addresses the latest clinical efficacy data and elucidates the scientific rationale behind each targeted treatment for atopic dermatitis.

Recent Advancements in the Atopic Dermatitis Mechanism.

Atopic dermatitis (AD) is a recurrent, chronic, inflammatory, itchy skin disorder that affects up to 20% of the pediatric population and 10% of the adult population worldwide. Onset typically occurs early in life, and although cardinal disease features are similar across all ages, different age groups and ethnicities present distinct clinical characteristics. The disease imposes a significant burden in all health-related quality of life domains, both in children and adults, and a substantial economic cost both at individual and national levels. The pathophysiology of AD includes a complex and multifaceted interplay between the impaired dysfunctional epidermal barrier, genetic predisposition, and environmental contributors, such as chemical and/or biological pollutants and allergens, in the context of dysregulated TH2 and TH17 skewed immune response. Regarding the genetic component, the loss of function mutations encoding structural proteins such as filaggrin, a fundamental epidermal protein, and the more recently identified variations in the epidermal differentiation complex are well-established determinants resulting in an impaired skin barrier in AD. More recently, epigenetic factors have facilitated AD development, including the dysbiotic skin microbiome and the effect of the external exposome, combined with dietary disorders. Notably, the interleukin (IL)-31 network, comprising several cell types, including macrophages, basophils, and the generated cytokines involved in the pathogenesis of itch in AD, has recently been explored. Unraveling the specific AD endotypes, highlighting the implicated molecular pathogenetic mechanisms of clinically relevant AD phenotypes, has emerged as a crucial step toward targeted therapies for personalized treatment in AD patients. This review aims to present state-of-the-art knowledge regarding the multifactorial and interactive pathophysiological mechanisms in AD.

The vicious circle mechanism in atopic dermatitis: psychological distress as cause and effect of atopic dermatitis

Introduction and purpose: Atopic dermatitis (AD) is chronic inflammatory skin disorder. It typically begins in infancy or childhood and might persist into adulthood. AD is characterized by dry, itchy, eczematous skin. The lesions can vary in intensification from mild to severe according to patient age or body region. AD requires ongoing management to control the symptoms. Skin manifestations along with the demand of treatment and care regimens significantly impact quality of life (QOL) in patients with AD. Individuals suffering from this condition are more prone to developing mental health disorders, which are often linked to emotional stress they experience. Exposure to stress exacerbates AD and stimulates skin changes, which in turn leads to intensification of treatment regimens. This cause-and-effect chain can be considered as a vicious circle mechanism. The aim of the review is to highlight the phenomenon by examining current literature on this topic in order to raise the awareness of healthcare professionals regarding this subject as well as implement appropriate and complete support for patients struggling with AD. A brief description of the state of knowledge: The pathophysiology of AD is multifactorial. Numerous studies explore the impact of stress on the deterioration of AD symptoms and delve into its pathogenic concepts. Simultaneously, researchers highlight increased psychological distress in AD patients, which surpass that observed in many other chronic conditions. Summary: Psychological factors play a significant role in AD. It demands considering mental health screening and support as a part of clinical practice, treating AD patients. Further research is necessary to provide efficient and comprehensive interventions.

Role of Calcineurin Inhibitors in the Management of Atopic Dermatitis in Children

Atopic dermatitis (AD) is a widespread chronic inflammatory skin disease that has a significant impact on various aspects of patient's life. This review presents modern view on AD pathophysiology, its correlation with other concomitant diseases, and covers practical aspects of external anti-inflammatory therapy implementation. The analysis of clinical studies has shown the significant role of calcineurin inhibitors in the effective treatment of AD in children from its first manifestations at early age.

Cutaneous Components Leading to Pruritus, Pain, and Neurosensitivity in Atopic Dermatitis: A Narrative Review.

Atopic dermatitis (AD) is a chronic, relapsing immunoinflammatory skin condition characterized by sensations such as pruritis, pain, and neuronal hypersensitivity. The mechanisms underlying these sensations are multifactorial and involve complex crosstalk among several cutaneous components. This review explores the role these components play in the pathophysiology of atopic dermatitis. In the skin intercellular spaces, sensory nerves interact with keratinocytes and immune cells via myriad mediators and receptors. These interactions generate action potentials that transmit pruritis and pain signals from the peripheral nervous system to the brain. Keratinocytes, the most abundant cell type in the epidermis, are key effector cells, triggering crosstalk with immune cells and sensory neurons to elicit pruritis, pain, and inflammation. Filaggrin expression by keratinocytes is reduced in atopic dermatitis, causing a weakened skin barrier and elevated skin pH. Fibroblasts are the main cell type in the dermis and, in atopic dermatitis, appear to reduce keratinocyte differentiation, further weakening the skin barrier. Fibroblasts and mast cells promote inflammation while dermal dendritic cells appear to attenuate inflammation. Inflammatory cytokines and chemokines play a major role in AD pathogenesis. Type 2 immune responses typically generate pruritis, and the type 1 and type 3 responses generate pain. Type 2 responses and increased skin pH contribute to barrier dysfunction and promote dysbiosis of the skin microbiome, causing the proliferation of Staphyloccocus aureus. In conclusion, understanding the dynamic interactions between cutaneous components in AD could drive the development of therapies to improve the quality of life for patients with AD.

Atopic Dermatitis: Pathophysiology.

The pathophysiology of atopic dermatitis is complex and multifactorial, involving elements of barrier dysfunction, alterations in cell-mediated immune responses, IgE-mediated hypersensitivity, and environmental factors. Loss-of-function mutations in filaggrin have been implicated in severe atopic dermatitis due to a potential increase in trans-epidermal water loss, pH alterations, and dehydration. Other genetic changes have also been identified, which may alter the skin's barrier function, resulting in an atopic dermatitis phenotype. The imbalance of Th2 to Th1 cytokines observed in atopic dermatitis can create alterations in the cell-mediated immune responses and can promote IgE-mediated hypersensitivity, both of which appear to play a role in the development of atopic dermatitis. One must additionally take into consideration the role of the environment on the causation of atopic dermatitis and the impact of chemicals such as airborne formaldehyde, harsh detergents, fragrances, and preservatives. Use of harsh alkaline detergents in skin care products may also unfavorably alter the skin's pH causing downstream changes in enzyme activity and triggering inflammation. Environmental pollutants can trigger responses from both the innate and adaptive immune pathways. This chapter will discuss the multifaceted etiology of atopic dermatitis, which will help us to elucidate potential therapeutic targets. We will also review existing treatment options and their interaction with the complex inflammatory and molecular triggers of atopic dermatitis.

Nonprescription Treatment Options.

The pathogenesis of atopic dermatitis (AD) is complex and multifactorial. However, recent advancements in the genetics and pathophysiology of AD suggest that epidermal barrier dysfunction is paramount in the development and progression of the condition (Boguniewicz M, Leung DYM, Immunol Rev 242(1):233-246, 2011). In addition to standard therapy for AD, there are a plethora of nonprescription treatment modalities which may be employed. Over-the-counter treatments for atopic dermatitis can come in the form of topical corticosteroids, moisturizers/emollients, and oral antihistamines. Though these treatments are beneficial, prescription treatments may be quicker acting and more efficacious in patients with moderate to severe disease or during flares. OTC agents are best used for maintenance between flares and to prevent progression of mild disease. Alternative and complementary treatments lack strong efficacy evidence. However, wet wraps, bleach baths, and other treatments appear to be promising when used in conjunction with conventional treatments. With the financial burden of atopic dermatitis ranging from 364million to 3.8billion dollars each year in the United States, we suspect this topic will gain further research attention.

Steroid-sparing effect of emollients in atopic dermatitis and psoriasis

The aim of the present article is to analyze the role of emollients in the topical management of atopic dermatitis and psoriasis and also to review the clinical studies available on the beneficial effect of co-therapy of emollients and topical corticosteroids. Understanding the stratum corneum's key involvement in the pathophysiology of atopic dermatitis and psoriasis has led to the development of new therapeutic approaches for treating not just inflammation but also restoring a healthy skin barrier. While topical corticosteroids are the cornerstones of treatment for atopic dermatitis and psoriasis, the potential risks of overuse (including atrophy, striae, dyspigmentation, and loss in epidermal barrier homeostasis) must be weighed against the benefits. These risks futher increase the necessity of finding non-steroidal treatments. Emollients aid the epidermal barrier function as they improve the oil and lipid levels and restore its protective function. Used regularly, emollients may reduce flare-ups and may also have a direct anti-inflammatory effect and may reduce the need to use topical corticosteroids, i.e. they have a ‘steroid sparing effect’.

Effectiveness Of Treatment Of Tralokinumab In Treatment Of Atopic Dermatitis In Adolescents.

Respected Madam, Atopic dermatitis (AD) is a prevalent inflammatory skin condition that affects people of all ages and can cause significant distress based on the severity of the condition. Researchers have examined focussed therapies that rely on a better understanding of the underlying pathophysiology of AD. While some therapies that target specific molecules, such as IL-13, IL-31, and OX40 (CD134), have been assessed, there is still much to be done regarding narrow-acting agents which act on a single molecule only.1 Tralokinumab, targeting interleukin-13 in patients with moderate-to-severe atopic dermatitis, was found to be an effective treatment hence beneficial in enhancing health-related quality of life (QoL) in adults.2 Paller et al. recently conducted a clinical trial focussing on adolescents (aged 12-17) with moderate to severe atopic dermatitis, finding that tralokinumab was both effective and safe, showcasing its potential as a treatment option for the said age group.3 Tralokinumab is a fully human monoclonal immunoglobulin G4 antibody that binds with remarkable affinity to the IL-13 cytokine, blocking its interaction with the IL-13 receptor and thus preventing downstream signalling and its ensuing inflammatory effects.4 Atopic dermatitis can be treated with the use of Janus Kinase inhibitors; however, these treatments have shown to result in unexpected adverse effects (AEs) due to the interaction of unintended pathways as well as the target ones; the most common being acne.5 Dupilumab, another therapeutic agent for atopic dermatitis, has been observed to cause conjunctivitis in adolescent patients. The study revealed that Tralokinumab (150mg/300mg) demonstrated to be an effectual treatment for atopic dermatitis, as the primary and secondary endpoints of the trial between Tralokinumab and placebo were statistically significant (p<0.05) while the frequency of conjunctivitis in adolescents was numerically lower than that reported with Dupilumab and the frequency of acne was numerically lower than that reported with Janus kinase inhibitors. As safe and efficient treatment of acute dermatitis for adolescents is already limited, Tralokinumab’s narrow focus on IL-13 molecule provides a more precise approach to treat atopic dermatitis in adolescents with fewer complications. Hence, it is imperative to look into this discovery for more effective treatment of the disease.

Reactive and proactive treatment in atopic dermatitis: Long-term disease control

Atopic dermatitis (AD) is a common, chronic, relapsing, inflammatory skin disease. The condition is prevalent worldwide affecting children more than the adult population. AD is associated with a significant adverse impact on a patient’s physical, psychological, and social life. Control of symptoms and disease activity and minimizing the number of flares are the goal of AD treatment. Available treatment options for AD include topical and/or systemic therapy. Despite significant advancements in the systemic treatment landscape including biologics and tyrosine kinase inhibitors, topical therapy remains valuable in the treatment of AD. In this article, we cover the pathophysiology of AD in brief along with the definitions of reactive and proactive approach of treatment. The concept of proactive treatment with topical therapy to control the disease and prevent flares is discussed along with the supporting published evidence.

The immunological and structural epidermal barrier dysfunction and skin microbiome in atopic dermatitis-an update.

Atopic dermatitis (AD) is a common, chronic and relapsing inflammatory skin disease with various clinical presentations and combinations of symptoms. The pathophysiology of AD is complex and multifactorial. There are several factors involved in the etiopathogenesis of AD including structural and immunological epidermal barrier defect, imbalance of the skin microbiome, genetic background and environmental factors. Alterations in structural proteins, lipids, proteases, and their inhibitors, lead to the impairment of the stratum corneum which is associated with the increased skin penetration and transepidermal water loss. The elevated serum immunoglobulin E levels and blood eosinophilia have been shown in the majority of AD patients. Type 2 T-helper cell immune pathway with increased expression of interleukin (IL)-4, IL-5, and IL-13, has an important role in the etiopathogenesis of AD. Both T cells and keratinocytes contribute to epidermal barrier impairment in AD via a dynamic interaction of cytokines and chemokines. The skin microbiome is another factor of relevance in the etiopathogenesis of AD. It has been shown that during AD flares, Staphylococcus aureus (S. aureus) colonization increased, while Staphylococcus epidermidis (S. epidermidis) decreased. On the contrary, S. epidermidis and species of Streptococcus, Corynebacterium and Propionibacterium increased during the remision phases. However, it is not clear whether skin dysbiosis is one of the symptoms or one of the causes of AD. There are several therapeutic options, targeting these pathways which play a critical role in the etiopathogenesis of AD. Although topical steroids are the mainstay of the treatment of AD, new biological therapies including IL-4, IL-13, and IL-31 inhibitors, as well as Janus kinase inhibitors (JAKi), increasingly gain more importance with new advances in the therapy of AD. In this review, we summarize the role of immunological and structural epidermal barrier dysfunction, immune abnormalities, impairment of lipids, filaggrin mutation and skin microbiome in the etiopathogenesis of AD, as well as the therapeutic options for AD and their effects on these abnormalities in AD skin.

Pathogenic mechanisms underlying itch in atopic dermatitis: the emerging role of neuroimmune interactions.

Itch is a frequent dermatological sensation that can occur in a variety of skin conditions, including atopic dermatitis, inflammatory disorders characterised by eczematous lesions and chronic itch. The pathogenic mechanisms that lead to itch in atopic dermatitis are not fully understood. The current knowledge of its aetiology highlights the complex interplay among multiple pathogenic factors such as epidermal barrier dysfunction, immune dysregulation, and its interaction with the nervous system. Furthermore, a relationship between itch intensity and certain factors such as stress, sleep disturbance, and pollutant exposure has often been shown in patients with itch. This article reviews the current advances in the processes behind itch signalling from the skin to the nervous system, focusing on atopic dermatitis pathophysiology. Studies investigating the underlying pathogenic mechanisms of atopic dermatitis have shown that itch management at the nervous system level may be sufficient to reduce itch sensation and improve skin lesions.

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.

Atopic Dermatitis: A Common Pediatric Diagnosis That Is Not Just Another Rash.

Emergency nurse practitioners are expected to assess and manage a variety of patients. These patients may present with urgent care-type complaints to severe life-threatening illnesses or injuries. For some, dermatological problems can sometimes be just as challenging as a critically ill patient. Atopic dermatitis (AD) is one, if not, the most common chronic inflammatory disease. Its presentation can vary depending on the age of the patient, the patient's skin tone, and other comorbidities. Patients often seek emergency care related to the condition itself or associated complications. This article includes a review of the pathophysiology, clinical manifestations, and standard management of AD. Finally, the potential complications of AD are discussed. A better understanding of AD will allow emergency nurse practitioners to properly identify and treat this chronic condition, as well as its complications.

Efficacy of the Radical Scavenger, Tempol, to Reduce Inflammation and Oxidative Stress in a Murine Model of Atopic Dermatitis.

Atopic dermatitis (AD) is the most common chronically relapsing inflammatory skin disease, predominantly common in children; it is characterized by an eczematous pattern generally referable to skin dryness and itchy papules that become excoriated and lichenified in the more advanced stages of the disease. Although the pathophysiology of AD is not completely understood, numerous studies have demonstrated the complex interaction between genetic, immunological, and environmental factors, which acts to disrupt skin barrier function. Free radicals play a key role by directly damaging skin structure, inducing inflammation and weakening of the skin barrier. Tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl) is a membrane-permeable radical scavenger, known to be a stable nitroxide, which exhibits excellent antioxidant effects in several human disorders, such as osteoarthritis and inflammatory bowel diseases. Considering the few existing studies on dermatological pathologies, this study aimed to evaluate tempol, in a cream formulation, in a murine model of AD. Dermatitis was induced in mice via dorsal skin application of 0.5% Oxazolone, three times a week for two weeks. After induction, mice were treated with tempol-based cream for another two weeks at three different doses of 0.5%, 1% and 2%. Our results demonstrated the ability of tempol, at the highest percentages, to counteract AD by reducing the histological damage, decreasing mast cell infiltration, and improving the skin barrier properties, by restoring the tight junction (TJs) and filaggrin. Moreover, tempol, at 1% and 2%, was able to modulate inflammation by reducing the nuclear factor kappa-light-chain-enhancer of the activated B cell (NF-κB) pathway, as well as tumor necrosis factor (TNF)-α and interleukin (IL)-1β expression. Topical treatment also attenuated oxidative stress by modulating nuclear factor erythroid 2-related factor 2 (Nrf2), manganese superoxide dismutase (MnSOD), and heme oxygenase I (HO-1) expression levels. The obtained results demonstrate the numerous advantages provided by the topical administration of a tempol-based cream formulation, in reducing inflammation and oxidative stress through modulation of the NF-κB/Nrf2 signaling pathways. Therefore, tempol could represent an alternative anti-atopic approach to treating AD, thereby improving skin barrier function.

Binding, Neutralization and Internalization of the Interleukin-13 Antibody, Lebrikizumab.

IL-13 is the primary upregulated cytokine in atopic dermatitis (AD) skin and is the pathogenic mediator driving AD pathophysiology. Lebrikizumab, tralokinumab and cendakimab are therapeutic monoclonal antibodies (mAb) that target IL-13. We undertook studies to compare in vitro binding affinities and cell-based functional activities of lebrikizumab, tralokinumab and cendakimab. Lebrikizumab bound IL-13 with higher affinity (as determined using surface plasma resonance) and slower off-rate. It was more potent in neutralizing IL-13-induced effects in STAT6 reporter and primary dermal fibroblast periostin secretion assays than either tralokinumab or cendakimab. Live imaging confocal microscopy was employed to determine the mAb effects on IL-13 internalization into cells via the decoy receptor IL-13Rα2, using A375 and HaCaT cells. The results showed that only the IL-13/lebrikizumab complex was internalized and co-localized with lysosomes, whereas IL-13/tralokinumab or IL-13/cendakimab complexes did not internalize. Lebrikizumab is a potent, neutralizing high-affinity antibody with a slow disassociation rate from IL-13. Additionally, lebrikizumab does not interfere with IL-13 clearance. Lebrikizumab has a different mode of action to both tralokinumab and cendakimab, possibly contributing to the clinical efficacy observed by lebrikizumab in Ph2b/3 AD studies.

The association between eosinophils (CD16+ eosinophils), basophils (CD203+ basophils), and CD23 B lymphocytes in patients with atopic dermatitis on dupilumab therapy: pilot study.

Eosinophils, basophils, and the molecule CD23 on B cells are involved in the pathophysiology of atopic dermatitis (AD). The molecule CD23isinvolved in the regulation of IgE synthesis and is expressed by activated B cells. The molecule CD16 is used to assess the activation of eosinophils and CD203 of basophils. The association between the count of eosinophils, basophils, CD16+ eosinophils, CD203+ basophils and the expression of the activation marker CD23 on B cells in patients with AD (with and without dupilumab therapy) is not described. The aim of this pilot study is to evaluate the association between the blood count of eosinophils, basophils, relative CD16+ eosinophils, relative CD203+ basophils, and the expression of molecule CD23 on B cells and on their subsets (total, memory, naive, switched, non-switched) in patients suffering from AD (with and without dupilumab therapy) and in control group. A total of 45 patients suffering from AD were examined; 32 patients without dupilumab treatment (10 men, 22 women, average age 35years), 13 patients with dupilumab treatment (7 men, 6 women, average age 43.4years), and 30 subjects as a control group (10 men, 20 women, average age 44.7years). Immunophenotype was examined by flow cytometry in which monoclonal antibodies with fluorescent molecules were used. For statistical analysis we used non-parametric Kruskal-Wallis one-factor analysis of variance with posthoc by Dunn's test with Bonferroni modification and the Spearman's rank correlation coefficient; for coefficients higher than 0.41, we report R2 (percent of variation explained). The absolute count of eosinophils was significantly higher in patients with AD (with and without dupilumab) in comparison to healthy subjects. The difference in the relative count of CD16+ eosinophils in patients with AD (with and without dupilumab therapy) compared with control is not statistically significant. In patients with dupilumab therapy the significantly lower count of relative CD203+ basophils was confirmed compared with control. The higher association between the count of eosinophils (absolute and relative) and the expression of CD23 marker on B cells was confirmed in patients with dupilumab therapy; in contrast, this association was low in patients with AD without dupilumab therapy and in healthy subjects. The higher association between the count of eosinophils (absolute and relative) and the expression of CD23 marker on B cells was confirmed in patients with AD under dupilumab therapy. It suggests that IL-4 production by eosinophils may play a role in B lymphocyte activation. The significantly lower count of CD203+ basophils has been demonstrated in patients with dupilumab therapy. This reduction of CD203+ basophil count may contribute to the therapeutic effects of dupilumab by reducing the inflammatory response and allergic reactions in patients with AD.

The Associations of Single Nucleotide Polymorphisms of the COL3A1, COL6A5, and COL8A1 Genes with Atopic Dermatitis.

The pathophysiology of atopic dermatitis (AD) is complex, multifactorial, and not fully understood. Genes encoding collagens, the most abundant proteins in the extracellular matrix (ECM), may play a potential role in the pathogenesis of AD. Our study aimed to estimate the associations between Col3A1/rs1800255, Col6A5 /29rs12488457, and Col8A1/rs13081855 polymorphisms and the occurrence, course, and features of AD in the Polish population. Blood samples were collected from 157 patients with AD and 111 healthy volunteers. The genotype distribution of the investigated collagens genes did not differ significantly between the AD and control subjects (p > 0.05). The AA genotype of Col3A1/rs1800255 was significantly associated with the occurrence of mild SCORAD (OR = 0.16; 95% Cl: 0.03-0.78; p = 0.02) and mild pruritus (OR = 18.5; 95% Cl: 3.48-98.40; p = 0.0006), while the GG genotype was significantly associated with severe SCORAD (OR = 6.6; 95% Cl: 1.23-32.35; p = 0.03). Regarding Col6A5/29rs12488457 polymorphism, the average SCORAD score was significantly lower in the group of patients with genotype AA than in patients with the AC genotype (39.8 vs. 53.4; p = 0.04). Nevertheless, both average SCORAD scores were high, and represent the moderate and severe grades of the diseases, respectively. The single nucleotide polymorphisms (SNPs) of COL3A1/ rs1800255 and Col6A5/29rs12488457 seem to be associated with AD courses and symptoms, suggesting new disease biomarkers. The modulation of collagens, the major component of the ECM, may serve as a therapeutic target of AD in the future.