Efficacy of dupilumab on chronic rhinosinusitis with nasal polyps and concomitant asthma in biologic-naive and biologic-pretreated patients.

OBJECTIVES: Dupilumab, an anti-IL-4 receptor monoclonal antibody (mAb), was recently approved for the treatment of severe chronic rhinosinusitis with nasal polyps (CRSwNP). The main objective of this study was to assess whether previous exposure to biological treatment affected the clinical outcomes in CRSwNP and asthma patients, treated with dupilumab over time. A collateral secondary objective was to analyse the effects over time of dupilumab in patients with and without aeroallergen sensitization. METHODS: Single-centre retrospective observational study on severe CRSwNP patients treated with dupilumab. Nasal polyp score (NPS), visual analogue scale (VAS) symptom score, sinonasal outcome test (SNOT-22), aeroallergen sensitization, total serum IgE levels, and blood eosinophil counts were assessed at baseline and after 4, 6 and 12 months. RESULTS: 42 patients were included, 40 (95.2%) had asthma. Twenty-one (50%) patients received dupilumab without prior biological treatment (Group A: naive) and 50% switched to dupilumab from previous biological treatment (Group B: pre-treated). NPS, VAS symptoms, SNOT-22 improved significantly after 12 months treatment in both groups of patients (p < 0.001). After 12 months, VAS overall symptom score showed a significant reduction from 6 (IQR, 4.6-8.6) and 6 (IQR, 3.8-7.1) for Group A and Group B patients respectively, to 1.2 (IQR, 0.8-2.7) and 1.2 (IQR, 0.2-2.5); NPS from 6 (IQR, 4.0-7.0) and 5 (IQR, 3.5-6.0), respectively, to 1 (IQR, 0.0-2.0) and 0 (IQR, 0.0-3.0) and SNOT-22 from 64 (IQR, 56-78) and 71 (IQR, 47.5-76.0) respectively, to 5.5 (IQR, 4-21) and 6 (IQR, 4-15). IgE reduced from 57 to 22.1 and from 46.9 to 30.2 in Group A and Group B respectively (p < 0.001). CONCLUSIONS: Dupilumab improves symptom severity, polyp size, and health-related quality of life, regardless of the presence or absence of comorbid aeroallergen sensitization and previous administration of biologic therapy.

Dupilumab proved to be effective in patients with severe chronic rhinosinusitis with nasal polyps (CRSwNP).We observed that dupilumab for CRSwNP leads to a very rapid improvement in polyps, symptoms, and quality of life, regardless of previous biologic treatment status and presence or absence of allergic rhinitis.VAS, SNOT-22 and NPS may be established as outcome markers in everyday clinical practice during dupilumab treatment.

TIM-3-driven macrophage polarisation is associated to recalcitrant chronic rhinosinusitis with nasal polyps.

Objective: This study evaluated the expression of TIM-3 and its influence on macrophage polarisation in recalcitrant chronic rhinosinusitis with nasal polyps (CRSwNP). Methods: We detected TIM-3 expression in serum and tissue samples of healthy controls (HC), primary CRSwNP, and patients with recurrent CRSwNP. Macrophage markers were detected among three groups, and their correlations with TIM-3 levels were examined. Macrophages from circulating blood were collected and used to examine the impact of TIM-3 on polarisation in vitro. Results: TIM-3 levels were enhanced in the CRSwNP group compared to the HC group. Tissue immunofluorescence revealed elevated TIM-3 expression in patients with CRSwNP, and patients with multiple recurrences exhibited higher TIM-3 levels compared to their first recurrence and baseline levels. Tissue CD163 and CD206 levels were higher in recurrent CRSwNP in comparison with primary cases and HCs, and had a positive correlation with TIM-3 levels. TIM-3 overexpression promoted M2 polarisation and enhanced TGF-ß1 and IL-10 secretion. Conclusions: TIM-3 expression was enhanced in patients with CRSwNP, especially in those undergoing revision surgeries. TIM-3 may be a novel biomarker for recalcitrant CRSwNP. TIM-3-driven M2 polarisation might be involved in the mechanisms of recurrent CRSwNP.

Differential regulation of viral entry-associated genes modulated by inflammatory cytokines in the nasal epithelium.

This study aimed to investigate the impact of different types of nasal inflammation on the regulation of entry-associated genes of respiratory viruses, including severe acute respiratory syndrome coronavirus 2 (SARS CoV-2), Middle East respiratory syndrome coronavirus (MERS-CoV), human coronavirus 229E (HCoV-229E), and influenza virus, in the nasal epithelium. Subjects were classified into three groups: control, eosinophilic chronic rhinosinusitis (ECRS), and noneosinophilic CRS (NECRS) groups. Angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine subtype 2 (TMPRSS2), alanyl aminopeptidase (ANPEP), dipeptidyl peptidase 4 (DPP4), and beta-galactoside alpha-2,6-sialyltransferase 1 (ST6GAL1), and beta-galactoside alpha-2,3-sialyltransferase 4 (ST3GAL4) were selected as key entry-associated genes for SARS-CoV-2, HCoV-229E, MERS-CoV, and influenza, respectively, and were evaluated. Brushing samples obtained from each group and human nasal epithelial cells cultured using an air-liquid interface system were treated for 7 days with typical inflammatory cytokines and analyzed using real-time polymerase chain reaction. Western blot analysis and confocal microscopy were performed. The entry-associated genes showed distinct regulation patterns in response to each interleukin-4 (IL-4), interleukin-13 (IL-13), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ). Specifically, ACE2 significantly decreased in type 2 cytokines (IL-4 and IL-13), while TMPRSS2 significantly decreased in type 1 cytokines (TNF-α and IFN-γ). ANPEP significantly decreased in both types of cytokines. Remarkably, DPP4 significantly increased in type 2 cytokines and decreased in type 1 cytokines. Moreover, ST6GAL1 and ST3GAL4 significantly increased in type 2 cytokines and decreased in type 1 cytokines, particularly IFN-γ. These findings were supported by western blot analysis and confocal imaging results, especially for ACE2 and DPP4. The findings regarding differential regulation suggest that patients with ECRS, primarily mediated by type 2 inflammation, may have lower susceptibility to SARS-CoV-2 and HCoV-229E infections but higher susceptibility to MERS-CoV and influenza infections.

Functions and Clinical Applications of Extracellular Vesicles in TH2 Cell-Mediated Airway Inflammatory Diseases: A Review.

Type 2 airway inflammation (T2AI), driven by type 2 innate lymphoid and CD4+ T helper 2 cells, leads to various diseases and conditions, such as chronic rhinosinusitis with nasal polyps, allergic rhinitis, and asthma. Emerging evidence suggests the involvement of extracellular vesicles (EVs) in these diseases. In this review, we describe the immunological T2AI pathogenic mechanisms, outline EV characteristics, and highlight their applications in the diagnosis and treatment of T2AI. An extensive literature search was conducted using appropriate strategies to identify relevant articles from various online databases. EVs in various biological samples showed disease-specific characteristics for chronic rhinosinusitis with nasal polyps, allergic rhinitis, and asthma, with some demonstrating therapeutic effects against these conditions. However, most studies have been limited to in vitro and animal models, highlighting the need for further clinical research on the diagnostic and therapeutic applications of EVs.

Rare presence and function of neuroendocrine cells in the nasal mucosa.

There is growing evidence that neurogenic inflammation contributes to the pathophysiology of upper airway diseases, with nasal hyperreactivity (NHR) being a key symptom. The rare neuroendocrine cells (NECs) in the epithelium have been linked to the pathophysiology of bronchial and intestinal hyperreactivity, however their presence in the nasal mucosa and their potential role in NHR remains unclear. Therefore, we studied the presence of NECs in the nasal epithelium of controls, allergic rhinitis patients and chronic rhinosinusitis with nasal polyps patients, and their link to NHR. The expression of typical NECs markers, CHGA, ASCL1 and CGRP, were evaluated on gene and protein level in human samples using real-time quantitative PCR (RT-qPCR), western blot, immunohistochemistry fluorescence staining, RNA scope assay, flow cytometry and single cell RNA-sequencing. Furthermore, the change in peak nasal inspiratory flow after cold dry air provocation and visual analogue scale scores were used to evaluate NHR or disease severity, respectively. Limited gene expression of the NECs markers CHGA and ASCL1 was measured in patients with upper airway diseases and controls. Gene expression of these markers did not correlate with NHR severity nor disease severity. In vitro, CHGA and ASCL1 expression was also evaluated in primary nasal epithelial cell cultures from patients with upper airway disease and controls using RT-qPCR and western blot. Both on gene and protein level only limited CHGA and ASCL1 expression was found. Additionally, NECs were studied in nasal biopsies of patients with upper airway diseases and controls using immunohistochemistry fluorescence staining, RNA scope and flow cytometry. Unlike in ileum samples, CHGA could not be detected in nasal biopsies of patients with upper airway diseases and control subjects. Lastly, single cell RNA-sequencing of upper airway tissue could not identify a NEC cluster. In summary, in contrast to the bronchi and gut, there is only limited evidence for the presence of NECs in the nasal mucosa, and without correlation with NHR, thereby questioning the relevance of NECs in upper airway pathology.

Suppressor of Cytokine Signaling Proteins 3 and 5 Potentially Delineate Polarization of Th cells in Chronic Rhinosinusitis.

Background: Chronic rhinosinusitis (CRS) is an inflammatory condition classified into chronic rhinosinusitis with nasal polyps (CRSwNP) and chronic rhinosinusitis without nasal polyps (CRSsNP). Th cells manage inflammatory cells in CRS. Suppressor of Cytokine Signaling (SOCS) proteins regulate Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway in Th cells by polarizing toward Th1, Th2, and Th17 cells. This study evaluated the levels of SOCS1,3,5 in CRS patients to find associations with Th cells. Methods: In this cross-sectional study, 20 CRSwNP patients, 12 CRSsNP patients, and 12 controls participated. The infiltration of CD4+ T cells was determined using immunohistochemistry. The expression of specific transcription factors and SOCS proteins was assessed using real-time PCR. Cytokine levels were evaluated using ELISA. SOCS protein levels were investigated using western blot analysis. Results: The expression of SOCS3 increased in the CRSwNP group compared to CRSsNP and control groups (p <0.001). SOCS3 protein levels increased in the CRSwNP group compared to CRSsNP (p <0.05) and control (p <0.001) groups. Although there was a significant difference in SOCS5 expression between CRSsNP and control groups, SOCS5 protein levels were significantly different between CRSsNP and control (p <0.001) and CRSwNP (p <0.05) groups. Conclusions: Targeted therapies may be suggested for CRS by modulating SOCS3 and SOCS5 proteins that are responsible for polarization of Th cells toward Th2 or Th1 cells, respectively. JAK-STAT pathway targeting, which encompasses numerous cells, can be limited to SOCS proteins to more effectively orchestrate Th cell differentiation.

Activation of the PGE2-EP2 pathway as a potential drug target for treating eosinophilic rhinosinusitis.

Current treatments of eosinophilic chronic rhinosinusitis (ECRS) involve corticosteroids with various adverse effects and costly therapies such as dupilumab, highlighting the need for improved treatments. However, because of the lack of a proper mouse ECRS model that recapitulates human ECRS, molecular mechanisms underlying this disease are incompletely understood. ECRS is often associated with aspirin-induced asthma, suggesting that dysregulation of lipid mediators in the nasal mucosa may underlie ECRS pathology. We herein found that the expression of microsomal PGE synthase-1 (encoded by PTGES) was significantly lower in the nasal mucosa of ECRS patients than that of non-ECRS subjects. Histological, transcriptional, and lipidomics analyses of Ptges-deficient mice revealed that defective PGE2 biosynthesis facilitated eosinophil recruitment into the nasal mucosa, elevated expression of type-2 cytokines and chemokines, and increased pro-allergic and decreased anti-allergic lipid mediators following challenges with Aspergillus protease and ovalbumin. A nasal spray containing agonists for the PGE2 receptor EP2 or EP4, including omidenepag isopropyl that has been clinically used for treatment of glaucoma, markedly reduced intranasal eosinophil infiltration in Ptges-deficient mice. These results suggest that the present model using Ptges-deficient mice is more relevant to human ECRS than are previously reported models and that eosinophilic inflammation in the nasal mucosa can be efficiently blocked by activation of the PGE2-EP2 pathway. Furthermore, our findings suggest that drug repositioning of omidenepag isopropyl may be useful for treatment of patients with ECRS.

Dupilumab: Mechanism of action, clinical, and translational science.

Allergic disease prevalence has increased globally with the subset of type 2 inflammatory diseases playing a substantial role. Type 2 inflammatory diseases may differ in clinical presentation, but they exhibit shared pathophysiology that is targeted by the unique pharmacology of dupilumab. Dupilumab binds to the interleukin (IL)-4 receptor alpha subunit (IL-4Rα) that blocks IL-4 and IL-13 signaling, two key drivers of type 2 inflammation. Herein, we review the mechanism of action and pharmacology of dupilumab, and the clinical evidence that led to the regulatory approvals of dupilumab for the treatment of numerous type 2 inflammatory diseases: atopic dermatitis, asthma, chronic rhinosinusitis with nasal polyposis, eosinophilic esophagitis, and prurigo nodularis.

CHI3L1 on fibrinolytic system imbalance in chronic rhinosinusitis with nasal polyp.

Background: Chronic rhinosinusitis (CRS) is an inflammatory disease affecting more than 10% of the global adult population. It is classified into Th1, Th2, and Th17 endotypes and eosinophilic and non-eosinophilic types. Th2-based inflammation and eosinophilic CRS (ECRS) are associated with tissue remodeling and fibrinolytic system impairment. Objective: To elucidate the role of eosinophils in inducing fibrin deposition in CRS nasal polyp tissues and explore potential regulatory mechanisms. Methods: We analyzed the expression of genes related to the serpin family and fibrinolytic system using Gene Expression Omnibus and Next-generation sequencing data. Differentially expression genes (DEGs) analysis was used to compare control and nasal polyp tissues, followed by KEGG and Gene ontology (GO) analysis. We measured the expression and correlation of plasminogen activator-1 (PAI-1), tissue plasminogen activator (t-PA), urokinase plasminogen activator (u-PA), and urokinase plasminogen activator surface receptor (u-PAR) in CRS tissues, and evaluated the effect of eosinophils on the fibrinolytic system using a cytokine array and co-culture. Results: Nasal polyp tissues showed upregulated PAI-1, u-PA, and u-PAR expression and downregulated t-PA expression. Fibrinolytic system-related genes positively correlated with Th2 cytokines, except for t-PA. Eosinophil-derived Chitinase-3-like protein 1 (CHI3L1) increased PAI-1 expression and decreased t-PA levels in fibroblasts and epithelial cells. The inhibition of CHI3L1 suppresses these alterations. Conclusion: CHI3L1 contributes to fibrin deposition by impairing the fibrinolytic system during nasal polyp formation. The regulation of CHI3L1 expression may inhibit fibrin deposition and edema in ECRS, presenting a potential treatment for this condition.

Rat nasal mucosa-derived ectodermal mesenchymal stem cells: A new therapeutic option for chronic rhinosinusitis.

OBJECTIVE: To investigate the effect of nasal mucosa-derived ectodermal mesenchymal stem cells (NM-EMSCs) on the inflammatory state of rats with chronic rhinosinusitis (CRS) and the underlying therapeutic mechanism. METHODS: NM-EMSCs were isolated and extracted to construct a rat model of CRS. Fifteen Sprague‒Dawley (SD) rats were randomly divided into three groups: CK + NS group rats were injected locally with saline in the nasal mucosa; CRS + NS group rats were injected locally with saline in the nasal mucosa; and CRS + EMSCs group rats were injected locally with NM-EMSCs in the nasal mucosa. One rat from the CRS + EMSCs group was randomly euthanized at 2, 4, and 6 days after injection, and the nasal mucosa tissues were collected for HE staining, Masson's trichrome staining, and periodic acid-Schiff staining. RESULTS: NM-EMSCs specifically expressing CD73, CD105, and CD90 were successfully isolated from the nasal mucosa of rats and were able to differentiate into adipocytes, osteoblasts, and chondrocytes. After saline and NM-EMSC injection, compared with those in the blank control CK + NS group, the nasal mucosa in the CRS + NS and CRS + EMSC groups exhibited obvious thickening, a large amount of inflammatory cell infiltration, and increased collagen and mucin distribution. Four days post-NM-EMSC injection, the thickening of the nasal mucosa in the CRS group was gradually alleviated, the inflammatory cell infiltration gradually decreased, and the distribution of collagen and mucin and the collagen-positive area gradually decreased. Moreover, only a small number of inflammatory cells were visible, and the distribution of mucins was limited to 6 days post-NM-EMSC injection. CONCLUSION: NM-EMSCs effectively attenuated inflammation in the nasal mucosa of CRS model rats.

Nasal brushing molecular endotyping distinguishes patients with chronic rhinosinusitis with nasal polyps with better response to dupilumab.

BACKGROUND: There is evidence of pathophysiologic diversity in chronic rhinosinusitis with nasal polyps (CRSwNP), but data characterizing the molecular endotypes of CRSwNP and their association with treatment are lacking. OBJECTIVE: This study aimed to identify gene signatures associated with CRSwNP endotypes, clinical features, and dupilumab treatment response. METHODS: Nasal brushing samples were collected from 89 patients randomized to dupilumab 300 mg every 2 weeks or placebo in the SINUS-52 trial (NCT02898454). Microarrays were used to identify transcriptional clusters and assess the relationship between gene expression and baseline clinical features and clinical response to dupilumab. Endotype signatures were determined using differential expression analysis. RESULTS: Two distinct transcriptional clusters (C1 and C2) were identified, both with elevated type 2 biomarkers. At baseline, C2 patients had higher mean Nasal Polyp Score and higher type 2 biomarker levels than C1 patients. At week 24, significant improvements in clinical outcomes (dupilumab vs placebo) were observed in both clusters, although the magnitude of improvements was significantly greater in C2 than in C1, and more C2 patients demonstrated clinically meaningful responses. Gene set enrichment analysis supported the existence of 2 molecular endotypes: C2 was enriched in genes associated with type 2 inflammation (including periostin, cadherin-26, and type 2 cysteine protease inhibitors), while C1 was enriched in genes associated with T cell activation and IL-12 production. CONCLUSIONS: Two distinct gene signatures associated with CRSwNP clinical features were identified; the endotype signatures were associated with clinical outcome measures and magnitude of dupilumab response.

Comparative safety of monoclonal antibodies in chronic inflammatory airway diseases (chronic sinusitis with nasal polyposis and asthma): A network meta-analysis.

OBJECTIVE: Several monoclonal antibodies (MoAbs) targeting specific type 2 immune reactions have been developed as innovative therapeutic approaches for chronic inflammatory airway diseases, such as chronic sinusitis with nasal polyps (CRSwNP) and asthma. However, the clinical safety of these MoAbs and how to choose them are not clear. Therefore, we aimed to assess the systemic drug- and dose-based safety of MoAbs in chronic airway inflammation using network meta-analysis (NMA). METHODS: Electronic databases were systematically searched for relevant studies published in English between January 2009 and December 2022. Eligible studies must have clearly reported adverse events (AEs) among the MoAbs' safety data. RESULTS: 1). Regarding serious AEs, mepolizumab was significantly safer than placebo; in terms of permanent treatment discontinuation, reslizumab and dupilumab were significantly safer than benralizumab. 2). Regarding asthma worsening, dupilumab was associated with the best safety profile; was safer than dupilumab/300 mg/q2-4w. 3). In terms of injection-site reactions, dupilumab posed a higher risk than placebo; dupilumab/300 mg/qw posed a higher risk than dupilumab/300 mg/q2w and dupilumab/300 mg/q2-4w; lebrikizumab/250 mg/q4w posed a higher risk than lebrikizumab/37.5 mg/q4w; mepolizumab/100 mg/q4w posed a higher risk than mepolizumab/75 mg/q4w; benralizumab/30 mg/q4-8w posed a higher risk than benralizumab/20 mg/q4-8w. 4) In CRSwNP patients combined with asthma, the risks of experiencing AEs were not increased. CONCLUSION: Overall, biologics are safe and well tolerated in chronic inflammatory airway disease. This drug- and dose-based NMA provides further evidence on the different safety profiles of different emerging MoAbs. This information may help guide rational drug use and provide clinical recommendations for choosing MoAbs. TRIAL REGISTRATION: SYSTEMATIC REVIEW REGISTRATION (PROSPERO #CRD42023387610).

The role of autophagy regulated by the PI3K/AKT/mTOR pathway and innate lymphoid cells in eosinophilic chronic sinusitis with nasal polyps.

BACKGROUND: The PI3K/Akt/mTOR pathway and autophagy are important physiological processes. But their roles in eCRSwNP remains controversial. METHODS: In this study, we used the eCRSwNP mouse model, PI3K/Akt/mTOR pathway inhibitors, and autophagy inhibitors and activators to investigate the regulatory effects of the PI3K/Akt/mTOR pathway on autophagy, and their effects on eosinophilic inflammation, and tissue remodeling. The role of ILC2s in eCRSwNP was also studied, and the relationship between ILC2s and autophagy was preliminarily determined. RESULTS: Our results show that eosinophilic inflammation in eCRSwNP mice could be inhibited by promoting the autophagy; otherwise, eosinophilic inflammation could be promoted. Meanwhile, inhibition of the PI3K/Akt/mTOR pathway can further promote autophagy and inhibit eosinophilic inflammation. Meanwhile, inhibiting the PI3K/Akt/mTOR pathway and promoting autophagy can reduce the number of ILC2s and the severity of tissue remodeling in the nasal polyps of eCRSwNP mice. CONCLUSIONS: We conclude that the PI3K/Akt/mTOR pathway plays roles in eosinophilic inflammation and tissue remodeling of eCRSwNP, in part by regulating the level of autophagy. The downregulation of autophagy is a pathogenesis of eCRSwNP; therefore, the recovery of normal autophagy levels might be a new target for eCRSwNP therapy. Furthermore, autophagy might inhibit eosinophilic inflammation and tissue remodeling, in part by reducing the number of ILC2s.

Sinonasal immunoglobulin G4-related disease: a case report of an atypical and rare entity.

BACKGROUND: Immunoglobulin G4-related disease is marked by extensive inflammation and fibrosis of an unknown autoimmune component, with an overall incidence ranging from 0.78 to 1.39 per 105 person-years. Sinonasal immunoglobulin G4-related disease is atypical and exceedingly uncommon in the existing literature, frequently manifesting clinically as chronic rhinosinusitis, epistaxis, and facial pain. CASE PRESENTATION: This report describes a 25-year-old Iraqi female who has been suffering from symptoms of chronic rhinosinusitis for 8 years. Despite undergoing several surgeries, there has been no improvement in her symptoms. A tissue biopsy that revealed dense lymphoplasmocytosis with noticeable plasma cell infiltration, storiform fibrosis, and obliterative angitis, along with positive immunohistochemical staining for Immunoglobulin G4 plasma cells, finally confirmed the diagnosis of sinonasal immunoglobulin G4-related disease. The patient responded well to oral prednisolone and methotrexate treatments. CONCLUSIONS: The main objective of the current report is to raise awareness among physicians about the significance of promptly identifying and diagnosing this rarity, thus preventing the adverse consequences linked to delayed diagnosis and treatment initiation.

Single cell RNA sequencing of human eosinophils from nasal polyps reveals eosinophil heterogeneity in chronic rhinosinusitis tissue.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by type 2 inflammation in the United States, but the actual roles that eosinophils play in CRSwNP remain largely unclear. OBJECTIVE: To reveal the roles and heterogeneity of eosinophils in nasal polyp (NP) tissue, we performed single cell RNA sequencing (scRNA-Seq) analysis of NP tissue. METHODS: Sinonasal tissues (NP and control sinus tissue) and patient matched peripheral blood (PB) samples were obtained from 5 control patients and 5 patients with CRSwNP. Eosinophils were enriched before processing for scRNA-Seq. The gene expression profiles in eosinophils were determined by microwell-based scRNA-Seq technology (BD Rhapsody platform). We predicted the overall function of NP eosinophils by Gene Ontology (geneontology.org) enrichment and pathway analyses and confirmed expression of selected genes by flow cytometry. RESULTS: After filtering out contaminating cells, we detected 5,542 eosinophils from control PB, 3,883 eosinophils from CRSwNP PB, 101 eosinophils from control sinus tissues (not included in further analyses), and 9,727 eosinophils from NPs by scRNA-Seq. We found that 204 genes were downregulated and 354 genes upregulated in NP eosinophils compared to all PB eosinophils (>1.5-fold, Padj < .05). Upregulated genes in NP eosinophils were associated with activation, cytokine-mediated signaling, growth factor activity, NF-κB signaling, and antiapoptotic molecules. NP eosinophils displayed 4 clusters revealing potential heterogeneity of eosinophils in NP tissue. CONCLUSIONS: Elevated eosinophils in NP tissue appear to exist in several subtypes that may play important pathogenic roles in CRSwNP, in part by controlling inflammation and hyperproliferation of other cells.

Serum Aspergillus fumigatus-Specific IgG as a Complementary Biomarker in Differentiating Endotypes of Chronic Rhinosinusitis: A Study on Its Role and Diagnostic Efficacy in Type 2 Inflammation.

BACKGROUND: Aspergillus is one of the most common pathogens causing fungal allergy in the respiratory tract. Serum Aspergillus fumigatus-specific immunoglobulin G (Af-sIgG) levels have been used as a biomarker for the diagnosis and treatment response monitoring in airway allergic diseases such as allergic bronchopulmonary aspergillosis and allergic fungal rhinosinusitis. However, its role in common primary chronic rhinosinusitis (CRS) was unclear. OBJECTIVE: This study aims to evaluate whether serum Af-sIgG level could serve as a biomarker for the disease presentation of primary CRS. METHODS: We obtained serum Af-sIgG levels from patients diagnosed as bilateral primary CRS refractory to medical treatment and evaluated the correlations between serum Af-sIgG levels and disease severity in patients with type 2 (T2) and non-T2 CRS. RESULTS: Patients with T2 CRS exhibited significantly higher serum Af-sIgG levels than non-T2 CRS patients. The cut-off value of serum Af-sIgG in T2 CRS was 20.9 mg/L, with an odds ratio of 3.8 (95% CI 1.17-12.20, P = .026). Furthermore, serum Af-sIgG levels were positively correlated with symptom scores evaluated by the Sino-Nasal Outcome Test-22 (SNOT-22) scores in T2 patients (P = .009). While stratified by SNOT-22 total scores, patients with severe disease had higher serum Af-sIgG levels only in T2 CRS (P = .034). In individual domains of SNOT-22 analysis, serum Af-sIgG levels showed a significant correlation with "ear/facial" symptom scores in the T2 group (P < .001). CONCLUSIONS: Serum Af-sIgG levels may serve as a supplementary objective biomarker that correlates with identification and subjective measurements of T2 CRS, and may be associated with symptoms arising from Eustachian tube dysfunction.

ALOX15+ M2 macrophages contribute to epithelial remodeling in eosinophilic chronic rhinosinusitis with nasal polyps.

BACKGROUND: Epithelial remodeling is a prominent feature of eosinophilic chronic rhinosinusitis with nasal polyps (eCRSwNP), and infiltration of M2 macrophages plays a pivotal role in the pathogenesis of eCRSwNP, but the underlying mechanisms remain undefined. OBJECTIVE: We sought to investigate the role of ALOX15+ M2 macrophages in the epithelial remodeling of eCRSwNP. METHODS: Digital spatial transcriptomics and single-cell sequencing analyses were used to characterize the epithelial remodeling and cellular infiltrate in eCRSwNP. Hematoxylin and eosin staining, immunohistochemical staining, and immunofluorescence staining were used to explore the relationship between ALOX15+ M2 (CD68+CD163+) macrophages and epithelial remodeling. A coculture system of primary human nasal epithelial cells (hNECs) and the macrophage cell line THP-1 was used to determine the underlying mechanisms. RESULTS: Spatial transcriptomics analysis showed the upregulation of epithelial remodeling-related genes, such as Vimentin and matrix metalloproteinase 10, and enrichment of epithelial-mesenchymal transition (EMT)-related pathways, in the epithelial areas in eCRSwNP, with more abundance of epithelial basal, goblet, and glandular cells. Single-cell analysis identified that ALOX15+, rather than ALOX15-, M2 macrophages were specifically highly expressed in eCRSwNP. CRSwNP with high ALOX15+ M2THP-1-IL-4+IL-13 macrophages had more obvious epithelial remodeling features and increased genes associated with epithelial remodeling and integrity of epithelial morphology versus that with low ALOX15+ M2THP-1-IL-4+IL-13 macrophages. IL-4/IL-13-polarized M2THP-1-IL-4+IL-13 macrophages upregulated expressions of EMT-related genes in hNECs, including Vimentin, TWIST1, Snail, and ZEB1. ALOX15 inhibition in M2THP-1-IL-4+IL-13 macrophages resulted in reduction of the EMT-related transcripts in hNECs. Blocking chemokine (C-C motif) ligand 13 signaling inhibited M2THP-1-IL-4+IL-13 macrophage-induced EMT alteration in hNECs. CONCLUSIONS: ALOX15+ M2 macrophages are specifically increased in eCRSwNP and may contribute to the pathogenesis of epithelial remodeling via production of chemokine (C-C motif) ligand 13.