Search

The clinical manifestations of atopic dermatitis (AD) and chronic nodular prurigo (CNPG) include pruritus and eczema/lesions, posing significant challenges for patients. Th2 cells and ILC2, marked by cytokine production—particularly IL-4/13—are crucial therapeutic targets. Despite displaying a dose-dependent lack of pruritus induction post-injection, IL-13 acts through the IL-13Rα1 and IL-13Rα2 receptor system. Our study focused on investigating ex vivo skin biopsies in AD (n = 17), CNPG (n = 14) and healthy controls (HC; n = 10), examining the gene expression landscape of interleukins linked with pruritus (IL-13, IL-4, IL-31) and their corresponding receptors. Compared to HC, results revealed a significant upregulation of IL-4, IL-13, and IL-13RA1 in AD, whereas CNPG did not show increased IL13 expression. Notably, the decoy receptor IL-13RA2 displayed intriguing patterns, with AD showing a marked increase compared to both HC and CNPG. Positive correlations between receptor expression and itch intensity and hyperkinesis sensation underscore clinical relevance, potentially serving as biomarkers. The findings suggest a pivotal role of IL-4 and IL-13, along with IL-13RA1, in pruritus pathogenesis in both entities, while IL-13 upregulation in AD is countered by IL-13RA2. The comparable expression of IL-13RA2 to HC in CNPG suggests the absence of this regulatory mechanism, potentially worsening the disease and leading to prolonged scratching behavior. These insights illuminate the intricate interplay of interleukins and receptors in different pruritus phenotypes, laying the groundwork for understanding underlying mechanisms and offering avenues for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Chronic prurigo (CPG) is a neuroinflammatory dermatosis characterized by prolonged pruritus lasting more than 6 weeks, pruriginous skin lesions, and repeated scratching. Patients with CPG suffer significantly from psychological distress and a marked impairment in their quality of life. The most common subtype of CPG is chronic nodular prurigo (CNPG, also called prurigo nodularis). In addition to the clinical features of CPG and the burden of disease, this CME article provides an overview of the significant advances in understanding the pathophysiology, including the associated therapeutic options for CPG. Dupilumab is the first approved therapy for moderate and severe CNPG to date from the European Medicines Agency (EMA) and the US Food & Drug Administration (FDA). It also highlights other agents currently being studied in Phase II and Phase III clinical, randomized, placebo-controlled trials. These include biologics such as nemolizumab (anti-IL-31-RA-mAb), vixarelimab/KPL-716 (anti-Oncostatin-M receptor β-mAb), and barzolvolimab/CDX-0159 (anti-KIT-mAb), as well as Janus kinase inhibitors such as povorcitinib/INCB054707 and abrocitinib, and opioid modulators such as nalbuphine., (© 2024 The Authors. Journal der Deutschen Dermatologischen Gesellschaft published by John Wiley & Sons Ltd on behalf of Deutsche Dermatologische Gesellschaft.)