Multiomics analysis identified IL-4-induced IL1RL1high eosinophils characterized by prominent cysteinyl leukotriene metabolism.

BACKGROUND: Clinical studies have demonstrated that IL-4, a type 2 cytokine, plays an important role in the pathogenesis of chronic rhinosinusitis and eosinophilic asthma. However, the direct effect of IL-4 on eosinophils remains unclear. OBJECTIVE: We aimed to elucidate the inflammatory effects of IL-4 on the functions of human eosinophils. METHODS: A multiomics analysis comprising transcriptomics, proteomics, lipidomics, quantitative RT-PCR, and flow cytometry was performed by using blood eosinophils from healthy subjects stimulated with IL-4, IL-5, or a combination thereof. RESULTS: Transcriptomic and proteomic analyses revealed that both IL-4 and IL-5 upregulate the expression of γ-gultamyl transferase 5, a fatty acid-metabolizing enzyme that converts leukotriene C4 into leukotriene D4. In addition, IL-4 specifically upregulates the expression of IL-1 receptor-like 1 (IL1RL1), a receptor for IL-33 and transglutaminase-2. Additional transcriptomic analysis of cells stimulated with IL-13 revealed altered gene expression profiles, characterized by the upregulation of γ-gultamyl transferase 5, transglutaminase-2, and IL1RL1. The IL-13-induced changes were not totally different from the IL-4-induced changes. Lipidomic analysis revealed that IL-5 and IL-4 additively increased the extracellular release of leukotriene D4. In vitro experiments revealed that STAT6 and IL-4 receptor-α control the expression of these molecules in the presence of IL-4 and IL-13. Analysis of eosinophils derived from patients with allergic disorders indicated the involvement of IL-4 and IL-13 at the inflamed sites. CONCLUSIONS: IL-4 induces the proallergic phenotype of IL1RL1high eosinophils, with prominent cysteinyl leukotriene metabolism via STAT6. These cellular changes represent potential therapeutic targets for chronic rhinosinusitis and eosinophilic asthma.

Development of allergic bronchopulmonary aspergillosis in a patient with nontuberculous mycobacterial-pulmonary disease successfully treated with dupilumab: A case report and literature review.

Pulmonary manifestations in patients with allergic bronchopulmonary aspergillosis (ABPA) and nontuberculous mycobacterial-pulmonary disease (NTM-PD) include bronchiectasis and mucus plugging. A 68-year-old woman, treated with antibiotics and inhaled corticosteroids for NTM-PD and asthma, presented with fever and wheezing. ABPA was diagnosed based on laboratory findings (elevated peripheral blood eosinophil counts and serum total IgE levels and positive Aspergillus-specific IgE and IgG) and imaging observation of a high-attenuation mucus plug. Systemic prednisolone was avoided to prevent NTM-PD progression. Dupilumab, a monoclonal antibody that blocks IL-4/13, was introduced to improve the clinical findings. Herein, we discuss the pathophysiological mechanisms underlying this rare comorbidity.