Predictive significance of tissue eosinophilia for nasal polyp recurrence in the Chinese population

The characterization and validation of regulated cell death-related genes in chronic rhinosinusitis with nasal polyps

BACKGROUND

Regulated cell death (RCD), a genetically controlled process mediated by specialized molecular pathways (commonly termed programmed cell death), plays pivotal roles in diverse pathophysiological processes. However, the landscape and functional implications of RCD subtypes in chronic rhinosinusitis with nasal polyps (CRSwNP) remain poorly characterized. This study aimed to systematically investigate the involvement of RCD mechanisms in the pathogenesis and progression of CRSwNP.

METHODS

Transcriptomic datasets (GSE136825, GSE23552, GSE198950, GSE196169, GSE156285) related to CRSwNP were retrieved from the Gene Expression Omnibus (GEO) database. A comprehensive panel of 18 RCD-associated gene sets was compiled through a systematic literature review. Gene set variation analysis (GSVA) was employed to profile RCD activation patterns in CRSwNP. Integrative bioinformatics approaches including weighted gene co-expression network analysis (WGCNA) and least absolute shrinkage and selection operator (LASSO) regression were implemented to identify hub RCD-related genes and construct a cell death index (CDI). Single-cell RNA sequencing (scRNA-seq) data were analyzed to map RCD dynamics across cellular subpopulations. Clinical validation was performed using qRT-PCR quantification of key genes in nasal polyp/inferior turbinate tissues, with the concurrent assessment of symptom severity via visual analogue scale (VAS) scores.

RESULTS

GSVA revealed significant upregulation of 8 RCD subtypes in CRSwNP: apoptosis, ferroptosis, necroptosis, entotic cell death, lysosome-dependent cell death, NETosis, immunogenic cell death, and anoikis. Pathway enrichment analysis demonstrated that RCD-related differentially expressed genes were predominantly involved in epithelial-mesenchymal transition (EMT) and immune-inflammatory regulation. Furthermore, the WGCNA algorithm and LASSO analysis identified 8 key cell death genes (PTHLH, GRINA, S100A9, SCG2, HMOX1, RNF183, TYROBP, SEMA7A), which were utilized to construct the cell death-related index (CDI). In training and validation cohorts, the CDI was significantly elevated in CRSwNP compared to control and exhibited high diagnostic performance, with elevated scores correlating with enhanced immune cell infiltration. Single-cell resolution analysis uncovered cell type-specific RCD activation patterns. Clinical validation confirmed significantly higher expression of S100A9, PTHLH, and HMOX1 in eosinophilic versus non-eosinophilic polyps. Notably, expression levels of PTHLH, S100A9, HMOX1, GRINA, and TYROBP showed strong positive correlations with VAS scores.

CONCLUSIONS

Our investigation delineates an RCD activation signature in CRSwNP pathogenesis, characterized by 8 key cell death modalities and their regulatory genes. The novel CDI exhibits promising diagnostic potential, while mechanistic insights suggest RCD pathways may drive disease progression through EMT potentiation and inflammatory cascade amplification. These findings provide a framework for developing RCD-targeted therapeutic strategies in CRSwNP.

Efficacy and safety of GR1802 in uncontrolled chronic rhinosinusitis with nasal polyps: Placebo-controlled phase 2 trial

BACKGROUND

Anti-IL-4 receptor subunit alpha (IL-4Rα) treatments can effectively treat eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP). However, their impact on the overall population of patients with uncontrolled CRSwNP remains unclear.

OBJECTIVES

We evaluated the safety and efficacy of GR1802, a novel anti-IL-4Rα monoclonal antibody, in patients with uncontrolled CRSwNP.

METHODS

Seventy patients with uncontrolled CRSwNP were randomized (1:1) to receive either GR1802 (300 mg with an initial doubled dose) or placebo every 2 weeks. Primary end points were the changes from baseline in nasal polyp score and nasal congestion score at week 16. Secondary end points mainly included change from baseline in Total Nasal Symptom Score (TNSS), 22-item Sino-Nasal Outcome Test (SNOT-22) score, and Lund-Mackay score. Efficacy (exploratory) was also analyzed in ECRSwNP and non-ECRSwNP subgroups. Safety was evaluated throughout the study.

RESULTS

In uncontrolled CRSwNP participants, GR1802 significantly improved nasal polyp score and nasal congestion score compared with placebo, with least squares mean differences of -2.1 (95% confidence interval, -2.6, -1.5) and -0.8 (95% confidence interval, -1.1, -0.4), respectively. Participants treated with GR1802 had significantly decreased TNSS, SNOT-22 score, and Lund-Mackay score. The subgroup analysis demonstrated that GR1802 improved the symptoms and quality of life in both ECRSwNP and non-ECRSwNP participants, as evidenced by changes in nasal polyp score, University of Pennsylvania Smell Identification Test score, and Lund-Mackay score. Treatment-related adverse events occurred in 19.4% of the GR1802 group and 17.6% of the placebo group.

CONCLUSION

GR1802 is well tolerated and effective in treating the overall population with uncontrolled CRSwNP.

Chinese Position Paper on Biologic Therapy for Chronic Rhinosinusitis With Nasal Polyps

Emerging biologics that selectively target key cytokines present a promising therapeutic alternative for patients suffering from severe, uncontrollable chronic rhinosinusitis with nasal polyps (CRSwNP). Despite the limited availability of registered biologics for CRSwNP treatment in China, the country is experiencing rapid development in this field. It is imperative to standardize the application of biologic agents in CRSwNP management in preparation for their future integration into the CRSwNP care pathway. The Rhinology Group, Chinese Society of Otorhinolaryngology-Head and Neck Surgery; the Rhinology Group, Chinese Medical Doctor Association of Otorhinolaryngology-Head and Neck Surgery; and the Nasal and Ocular Allergy Group, Chinese Society of Allergy have convened an expert panel consisting of principal investigators experienced in clinical trials of biologic treatment for CRSwNP. This expert panel was assembled to discuss the application of biologic agents in patients with CRSwNP in China. Additionally, the latest findings on the pathogenesis of CRSwNP, mechanisms of biologic agents, and efficacy and safety of biologic treatment in patients with CRSwNP were reviewed, with a special emphasis on research evidence from China. The expert panel reached a consensus on several critical issues, including criteria for the prescription, treatment course, and efficacy evaluation from a Chinese perspective. This position paper aims to guide Chinese physicians in the use of biologic agents for patients with CRSwNP. As our experience with biologic treatment continues to grow, this position paper will be further updated.

Amphiregulin Mediates Epithelial Cell-Eosinophil Interactions and Amplifies Inflammation in Chronic Rhinosinusitis With Nasal Polyps

BACKGROUND

Eosinophils easily accumulate in the intra-epithelial layer and subepithelial regions in eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP). While several factors influence the migration of eosinophils from peripheral blood to extravascular tissues, the triggers and role of eosinophils near the epithelial layer in CRSwNP remain unclear.

METHODS

We examined interactions between eosinophils and epithelial cells using co-culture systems. We assessed the expression of amphiregulin (AREG) in CRSwNP epithelial cells and investigated its impact on epithelial barrier function, eosinophil activation, and migration. These effects were further validated in a CRSwNP mouse model treated with an AREG-blocking antibody.

RESULTS

Co-culturing blood eosinophils and primary epithelial cells from CRSwNP patients decreased tight junction expression and increased eosinophil activation. Epithelial cells from ECRSwNP patients expressed higher levels of AREG than those from non-eosinophilic CRSwNP (non-ECRSwNP) patients, particularly in basal cells. As measured in the culture medium by ELISA, both blood eosinophils and primary epithelial cells automatically secreted AREG. Our in vitro experiments demonstrated that AREG impaired epithelial barrier function and facilitated eosinophil migration and activation. Confirmatory studies in a CRSwNP mouse model indicated that blocking AREG reduced the number of nasal polyp-like lesions, mucosal thickness, and eosinophil infiltration, while restoring the expression of tight junction proteins.

CONCLUSION

The upregulation of AREG triggers eosinophil migration and mediates the interaction between epithelial cells and eosinophils, thereby enhancing chronic inflammation in CRSwNP. Our study highlights the therapeutic potential of anti-AREG antibodies in CRSwNP, offering a promising strategy for treating human eosinophilic sinus diseases.

Tissue eosinophil level as a predictor of control, severity, and recurrence of Chronic Rhinosinusitis with Nasal Polyps

Introduction

The histopathologic study of nasal polyps establishes endotype features of chronic rhinosinusitis (CRS). A tissular eosinophil count greater than 10 per high power field (HPF) classifies this condition as type 2 inflammation. Blood and mucosal eosinophils are suggested as biomarkers of severity and control of CRS. Additionally, a tissular eosinophil count greater than 55 per HPF has been related to a high risk of recurrence in the Asian population. Our study aims to determine whether tissue eosinophil count is associated with the control, severity, and recurrence of Chronic Rhinosinusitis with Nasal Polyps (CRSwNP).

Methods

An observational study of patients with CRSwNP who underwent nasal mucosa biopsy was conducted between June 2021 and November 2023. Histopathologic features, asthma control, CRSwNP control and severity according to the POLINA consensus, quality of life parameters, recurrence of CRSwNP, and laboratory markers were recorded and compared with the tissular eosinophil count.

Results

A total of 108 cases were included. The majority (70.4%) had concomitant asthma, with 31.5% of the cases having well-controlled disease. Most patients had uncontrolled (57.4%) and severe (62%) CRSwNP. Fifty-four cases underwent surgery and 43.5% experienced recurrence. More than half had a SNOT-22 score greater than 50 points. Eighty-one percent of patients had a tissular eosinophil count greater than 10 per HPF, and 60.2% had blood eosinophilia greater than 0.3 × 10 3 . Blood eosinophilia was related to CRSwNP severity and control. No significant differences were found between tissue eosinophil count and the severity, control, and recurrence of CRSwNP.

Conclusion

Tissue eosinophil levels were not a marker of control, severity, and recurrence of CRSwNP in our data. Blood eosinophil levels, however, were a marker of CRSwNP control and severity.

Serum 25-hydroxyvitamin D levels and peripheral blood eosinophil percentages as predictive indicators for eosinophilic chronic sinusitis with nasal polyps

PURPOSE

Chronic rhinosinusitis (CRS) has a high incidence rate and different endotypes. Serum 25-hydroxyvitamin D (25(OH)D) deficiency is common in patients with eosinophilic and non-eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP and nECRSwNP, respectively). This study explored the relationship between serum 25(OH)D levels and CRS risk and determined the value of combining serum 25(OH)D with peripheral blood markers in distinguishing between ECRSwNP and nECRSwNP.

METHODS

This study enrolled 275 CRS patients and 298 healthy controls. The relationship between serum 25(OH)D levels and CRS risk was determined using logistic regression after propensity score matching (PSM). The efficiency of various peripheral blood markers in distinguishing between ECRSwNP and nECRSwNP was assessed using a decision-tree model.

RESULTS

The final analysis included 189 CRS patients and 189 controls after 1:1 PSM. Serum 25(OH)D levels were significantly lower in CRS patients than in controls. Patients with mild CRS showed higher serum 25(OH)D levels than those with moderate or severe CRS, and ECRSwNP patients had lower serum 25(OH)D levels than nECRSwNP patients (all Ps < 0.05). Eosinophil percentages and IgE levels were independent risk factors for ECRSwNP, whereas serum 25(OH)D was an independent protective factor. 25(OH)D deficiency increased the ECRSwNP risk (OR = 3.074, P = 0.04). An eosinophil percentage ≥ 5% and a 25(OH)D level < 61.8 nmol/L could be used to predict ECRSwNP, with training and test set accuracies of 89.7% and 85.7%, respectively.

CONCLUSION

Our findings suggest that serum 25(OH)D deficiency is an independent risk factor for CRS, especially ECRSwNP. Combining serum 25(OH)D levels with peripheral eosinophil percentages could be a promising biomarker for ECRSwNP.

Targeting PDK1: A novel approach to combat hypoxia-induced epithelial-mesenchymal transition in chronic rhinosinusitis with nasal polyps

BACKGROUND

Hypoxia is a prevalent pathological process in chronic rhinosinusitis with nasal polyps (CRSwNP), leading to a cascade of pathological events, including epithelial-mesenchymal transition (EMT). However, the mechanisms underlying hypoxia-induced EMT remain unclear. This study aims to elucidate the mechanisms driving EMT under hypoxic conditions in CRSwNP.

METHODS

Transcriptome and proteome analyses of hypoxia-treated human nasal epithelial cells (HNECs) were performed to identify key molecules and pathways. The expression of hypoxia-inducible factor-1α (HIF-1α), pyruvate dehydrogenase kinase (PDK1), lactate dehydrogenase A (LDHA), and EMT markers was assessed in nasal tissues from CRSwNP patients. In vitro, cultured HNECs were exposed to hypoxia and lactate, or overexpressed PDK1, to evaluate changes in EMT markers.

RESULTS

Hypoxia activated the glycolysis-related pathway in HNECs, with PDK1 and LDHA identified as significantly upregulated glycolysis-related enzymes. The expression of PDK1 and LDHA was closely correlated with HIF-1α and EMT markers in nasal tissues. Hypoxia induced an increase in PDK1 and LDHA expression, lactate production, and EMT occurrence in HNECs. PDK1 overexpression or lactate stimulation also triggered EMT, while PDK1 inhibition attenuated hypoxia-induced EMT in HNECs.

CONCLUSIONS

This study is the first to reveal that hypoxia-induced activation of PDK1 plays a critical role in regulating EMT by promoting lactate production, thereby providing a potential therapeutic target for CRSwNP.

Fluctuation of tissue eosinophils in chronic rhinosinusitis with nasal polyp

INTRODUCTION

Tissue eosinophil count (TEC) is recommended for defining Type 2 chronic rhinosinusitis with nasal polyps (CRSwNP). TEC is usually assessed by a one-time polyp biopsy. Because TEC may change over time, its reliability for diagnosing type 2 CRSwNP has not been previously assessed. This study aims to explore whether TEC fluctuates across different time points.

METHODS

Adult patients with CRSwNP were prospectively recruited at Rajavithi Hospital, Thailand. Participants who had used any form of steroids within 4 weeks were excluded. Polyps were taken for TEC evaluation upon recruitment and repeated at 3 and 6 months. Participants were assessed using the 22-items Sinonasal Outcome Test (SNOT-22), Lund-Kennedy endoscopic score (LKES), blood eosinophil count, and its percentage at each time point.

RESULTS

Thirty-seven participants were enrolled. The medians (Quartiles 1-3) of TEC were 17 (4-53.5), 19 (5-47.5), and 21 (4.5-51) cells/high-powered field at 0, 3, and 6 months, respectively. Friedman's two-way analysis of variance showed no statistical differences across the three time points for TEC (p = 0.53), blood eosinophil counts (p = 0.61), blood eosinophil percentages (p = 0.23), SNOT-22 (p = 0.21), or LKES (p = 0.23). TEC significantly correlated with blood eosinophil counts at 0 and 3 months and with blood eosinophil percentages at 0, 3, and 6 months (all p < 0.05).

CONCLUSION

The study showed that TEC did not significantly fluctuate over time, aligning with blood eosinophil levels, SNOT-22, and LKES. This stability within the 6-month period supports the reliability of TEC from a single biopsy for clinical use in managing CRSwNP.

Arginine-Rich Peptides Regulate the Pathogenic Galectin-10 Crystallization and Mitigate Crystallopathy-Associated Inflammation

Protein self-assembly into a crystal in vivo triggers acute or chronic organ injury that can lead to intractable diseases lacking specific treatment options. In this study, we report the discovery of ionic arginine-rich peptides to disrupt the pathogenic galectin-10 (gal-10) crystallization, where the aberrant deposition of gal-10 crystals in airways causes the activation of IL-1β-dependent inflammation and the stimulation of epithelial cells to produce TNF-α. Gal-10 crystals show susceptibility to pH changes and charged residue substitutions at the protein packing interfaces, manifesting the role of charge-charge attractions across protein-protein interaction interfaces in governing gal-10 crystallization. To dissolve the gal-10 crystal, the ionic peptides R9 and R12Y8 were identified to eliminate the interprotein charge-charge interactions. The efficacy of R12Y8 in mitigating the gal-10 crystallopathy in vivo was assessed in a crystal-induced lung inflammation mice model. The mice intratracheally administrated by R12Y8 exhibited a downregulated release of proinflammatory cytokines and reduced infiltration of inflammatory cells in the lungs. Our study demonstrates that the pathogenic gal-10 crystallization is readily eliminated by R-rich peptides, which may display translational potentials for the treatment of gal-10 crystallopathy.

Unveiling the Impact of Total Body Fluid Dynamics on Chronic Rhinosinusitis With Sinonasal Polyposis

BACKGROUND

This study investigated the role of total body fluid dynamics in developing polyposis in patients with chronic rhinosinusitis. There is a significant gap in our understanding of body fluid dynamics in the pathogenesis of sinonasal polyposis. This preliminary research will be sensitized to explore hidden facts in this field further.

METHODS

In this cross-sectional study at a tertiary care hospital, 60 participants were enrolled, comprising 30 patients diagnosed with sinonasal polyposis and 30 controls without polyps. The measured parameters included total body water, excess body water, serum osmolality, albumin, creatinine, sodium, eosinophil count, arterial pH, and hematocrit. The t-test/Mann-Whitney U test and chi-square test were used for continuous and categorical variable analysis, respectively. Univariate and multivariate logistic regression was done to identify potential predictors, and model performance was evaluated using the receiver operating characteristic (ROC) curves, with an optimal classification cut-off of 0.5 for the area under the curve (AUC).

RESULTS

The mean age of cases was 34.03 ± 12.76 years, and that of controls was 34.77 ± 12.06 years. Amongst cases, 60% were males and 40% were females, while the control group had an equal distribution of males and females. The mean total body water level in patients with sinonasal polyposis was slightly higher than in those without polyps (34.42 ± 5.26 l vs. 32.38 ± 5.86 l). Moreover, the likelihood of developing sinonasal polyposis was twice as high in patients with excess body water compared to those without, as suggested by an adjusted odds ratio (OR) of 2.08. However, this association was not statistically significant (95% CI: 0.83-5.19, p = 0.116). Patients with polyposis also showed higher serum creatinine levels (0.94 mg/dL) than controls (0.80 mg/dL, p = 0.002). Univariate logistic regression indicated that a 1 mg/dL increase in serum creatinine level was associated with a 2.4-fold increase in the likelihood of polyposis (OR = 2.42, 95% CI: 1.30-4.50, p = 0.005). Multivariate analysis confirmed the significance of serum creatinine level (adjusted OR = 3.36, 95% CI: 1.42-7.97, p = 0.006), with an AUC of 0.803, demonstrating good discriminative ability. The model's accuracy, sensitivity, and specificity were 66.7%, 73.3%, and 60%, respectively.

CONCLUSIONS

Significantly elevated serum creatinine levels in patients with sinonasal polyposis may suggest a potential link with renal function or fluid regulation, warranting further research in larger cohorts to clarify this relationship. The regression model indicated a positive correlation between excess body water and the development of polyposis, with a weaker trend observed for other parameters. However, due to insufficient evidence, further research involving larger sample sizes across diverse geographic regions is recommended to validate their roles in the pathogenesis of sinonasal polyps.

Efficacy of vidian neurectomy in treating chronic rhinosinusitis with nasal polyps combined with allergic rhinitis: A systematic review and meta-analysis

OBJECTIVE

To evaluate the impact of additional vidian neurectomy or posterior nasal neurectomy in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and allergic rhinitis (AR), compared to the outcomes of conventional endoscopic sinus surgery alone.

METHODS

Up to May 2024, six databases were systematically searched. We evaluated studies that compared the clinical improvement of chronic sinusitis-related symptoms and endoscopic findings between the neurectomy group (endoscopic sinus surgery plus vidian neurectomy or posterior nasal neurectomy) and the control group (endoscopic sinus surgery only).

RESULTS

The neurectomy group showed a significant reduction in the Lund-Kennedy endoscopic score (SMD = -1.3163 [-1.6519; -0.9807]; I² = 53.3 %). However, this treatment did not have a significant effect on the Quality-of-life score (SMD = -0.1222 [-0.3427; 0.0983]; I² = 27.5 %) or patient-reported nasal symptom-related VAS scores (SMD = -1.6690 [-3.7062; 0.3682]; I² = 96.3 %). In the subgroup analyses of these results according to time points of measurement, the Lund-Kennedy endoscopic score was statistically lower in the treatment group during treatment periods (postop 6months, 12months, and 24months). However, there were no statistically significant differences in Quality-of-life score and VAS between the treatment and control groups during all treatment periods. There was no significant difference in the recurrent rate of CRS during the following up periods (odds ratio=0.5263 [0.1518; 1.8254], I2 = NA) between two groups. Regarding the adverse effect of neurectomy, this additional procedure did not induce the postoperative bleeding (odds ratio=0.8886 [0.3411; 2.3150]; I2 = 0.0 %) and dry eye related discomfort (odds ratio=65.3560 [0.1044; 40,908.1619]; I2 = 88.9 %) significantly compared to control group.

CONCLUSIONS

Additional neurectomy shows better efficacy in improving endoscopic findings and is safer in patients with CRSwNP combined with AR; however, more clinical studies are needed to evaluate its long-term symptomatic effects and disease recurrence.

The role of fibroblast in chronic rhinosinusitis with nasal polyps: a key player in the inflammatory process

INTRODUCTION

Fibroblasts are the primary supporting cells in connective tissue and have long been thought to contribute to chronic rhinosinusitis with nasal polyps (CRSwNP) by producing extracellular matrix (ECM), leading to fibrosis and tissue remodeling. However, recent studies have highlighted the critical role of nasal polyp-derived fibroblasts (NPDFs) in triggering and intensifying the inflammatory response in CRSwNP.

AREAS COVERED

This review undertook a comprehensive literature search across the PubMed database, Web of Science since 2000, offering an in-depth summary of the pivotal role of NPDFs in tissue remodeling and inflammatory responses in CRSwNP. Additionally, single-cell RNA sequencing data provides a deeper exploration of the heterogeneity and functional mechanisms of fibroblasts in CRSwNP. Consequently, these insights point to fibroblasts as promising therapeutic targets for effectively treating CRSwNP.

EXPERT OPINION

Current data underscore the essential role of fibroblasts in the pathogenesis of CRSwNP. Fully elucidating the specific mechanisms by which fibroblasts contribute to the disease process is crucial for developing targeted therapies. Furthermore, advancements in single-cell RNA sequencing pave the way for selectively targeting and depleting pathological fibroblast subpopulations. Despite these advancements, the clinical development of fibroblast-targeted therapies in CRSwNP remains challenging.

Alterations of gut microbiome in eosinophilic chronic rhinosinusitis

PURPOSE

A growing body of evidence has elucidated that the gut microbiota has a crucial impact on the pathophysiological process of atopic diseases. Eosinophilic chronic rhinosinusitis with nasal polyps (eCRSwNP) is a local atopic disease of the systemic immune response. Alterations in the gut microbiome in eCRSwNP patients remain largely undefined.

METHODS

16S rRNA gene sequencing was performed in a cross-sectional study of 17 eCRSwNP patients, 9 noneCRSwNP patients and 13 healthy controls, and gut microbiota DNA sequencing between each pair of groups was compared using bioinformatic methods.

RESULTS

Compared with that of healthy controls, the gut microbiomes of eCRSwNP patients were characterised by a distinct overall microbial composition. However, no significant differences were found in the alpha diversity of the gut microbiota between patients and healthy controls. The distinct differences in microbial composition were significantly correlated with the severity of disease. At the genus level, the abundance of Faecalibacterium positively correlated with Lund-Mackay CT scores. Similarly, the abundance of Turicibacter positively correlated with the percentage of tissue eosinophils.

CONCLUSIONS

We found alterations in the gut microbiome in eCRSwNP patients, and the alterations in the gut microbiome were correlated with the severity of disease.

Patterns of recurrence in patients with CRSwNP who underwent complete FESS

PURPOSE

To analyze recurrence patterns of chronic sinusitis with nasal polyposis (CRSwNP) in patients who underwent complete FESS and identify predisposing factors for different patterns of recurrence.

METHODS

Retrospective analysis of patients with CRSwNP who underwent complete FESS at our tertiary medical center. Recurrence patterns were classified into edema, polyp and normal endoscopy, as well as into early (within 6 months) and late recurrence. Statistical analysis to identify risk factors for recurrence included univariate, multivariate logistic regression and cox regression models.

RESULTS

114 patients were included with an average follow-up of 27 months. 91% were categorized as type-2 inflammation. Recurrence was observed in 65.8% of patients within a mean of 12.9 months. 46.7% had polyp recurrence while 53.3% had edema recurrence. Early recurrence was observed in 41%. Serum eosinophilia > 500 cells/uL was found to be significantly associated with recurrence (RR = 1.62, p-value = 0.046), and particularly with polyp recurrence (RR = 3.9, p-value = 0.001). No predictive factors for early recurrence were identified. Edema recurrence was managed with intranasal corticosteroids while polyp recurrence required systemic therapy including biologic therapy.

CONCLUSIONS

In this study, two thirds of patients experienced post operative recurrence, either mucosal edema or nasal polyps, with similar frequency during an average follow up of over 2 years. Early recurrence was noted in 41% of recurrent cases. Serum eosinophils > 500 cells/uL was the only risk factor for recurrence on multivariate analysis, more accurate markers are needed for improved treatment allocation to CRSwNP patients.

The role of CD24hiCD27+ regulatory B cells in human chronic rhinosinusitis with/without nasal polyps

BACKGROUND

Regulatory B cells (Bregs) reduce allergic and autoimmune inflammation. However, their role in chronic rhinosinusitis (CRS) remains unknown. This study investigated the frequency and function of Breg subsets in the peripheral blood of patients with CRS.

METHODS

The demographic and clinical characteristics were compared among control, CRSsNP, neCRSwNP, and eCRSwNP groups. The expression of various Breg subtypes was evaluated in peripheral blood mononuclear cells (PBMCs) of patients with eosinophilic CRS with nasal polyps (eCRSwNP), non-eosinophilic CRS with nasal polyps (neCRSwNP), CRS without nasal polyps (CRSsNP). CD19+CD24hiCD27+ B cells (B10 cells) were isolated by flow cytometry, followed by RNA sequencing (RNA-seq). Finally, IL-10 secreted by B10 cells were evaluated through the intracellular stain.

RESULTS

A higher number of eosinophils in peripheral blood and nasal polyps were found in eCRSwNP compared with neCRSwNP, CRSsNP, and control groups. The frequency of B10 in the peripheral blood B cells (B10%) of patients with eCRSwNP was significantly lower than that in the neCRSwNP and control groups. B10% was negatively correlated with the quantity of tissue eosinophils, and the percentage and absolute value of peripheral blood eosinophils. The eCRSwNP, neCRSwNP and control groups had 1403 differentially expressed genes, 35 of which were identified in four highly enriched pathways. Additionally, the frequency of IL-10+B10 cells in peripheral blood was lower in patients with eCRSwNP than in the neCRSwNP and control groups.

CONCLUSION

This study is the first to reveal differences in both the quantity and IL-10 secretion of B10 cells in patients with eCRSwNP and neCRSwNP. These variations were strongly negatively associated with eosinophils in nasal polyps and peripheral blood. IL-10+B10 cells may play a key role in the pathological mechanisms of CRS, particularly the recurrence of eCRSwNP.

Significance as a Prognostic Factor of Eosinophil Count in Nasal Polyp Tissue in Patients with Chronic Rhinosinusitis Accompanied by Asthma

Background/Objectives: Patients with chronic rhinosinusitis (CRS) accompanied by asthma often show poor prognoses and require continuous management. This study aimed to assess the prognostic value of eosinophil counts in nasal polyp tissue for selecting individuals who would benefit from ongoing management in CRS patients with asthma. Methods: Patients with asthma who underwent endoscopic sinus surgery for CRS with nasal polyps were included in the study. Eosinophil counts in nasal polyp tissues were quantified, and retrospective data were collected from laboratory and clinical findings, including endoscopic examinations, CT scans, and Japan Endoscopic Sinus Surgery Rating and Evaluation Committee (JESREC) scores. Disease control status was evaluated through endoscopic examination 6 months post-surgery. Results: A total of 42 patients were divided into two groups based on their disease management status 6 months post-operation: the well-control group (24 patients, 57.14%) and the poor-control group (18 patients, 42.86%). Demographics and laboratory findings did not show significant differences between the groups. However, the JESREC score (p = 0.04) and tissue eosinophil count (p = 0.02) were significantly different. Multivariate analysis identified tissue eosinophil count as the only risk factor associated with prognosis, with a cut-off value of 90/HPF. Conclusions: In CRS patients with asthma, high tissue eosinophil counts in nasal polyps were associated with poor disease control, which is the most potent predictor of prognosis. The assessment of eosinophil counts in nasal polyp tissue could aid in identifying patients who would benefit from continuous management and tailored interventions for improved outcomes.

Based on the clinical features of cytologically intrinsic chronic rhinosinusitis with nasal polyps

BACKGROUND

The clinical phenotypes of CRS, such as the presence or absence of polyps, cannot well reflect the pathophysiological mechanisms and characteristics of patients. Only by distinguishing the different internal types of CRS can we individualize patients more accurately.

OBJECTIVE

To investigate the clinical characteristics of chronic rhinosinusitis with different cell types (CRSwNP), and to provide a reference for the diagnosis and treatment of CRSwNP.

MATERIALS AND METHODS

The cytological endotypes of CRSwNP were divided into five groups by cluster analysis.

RESULTS

There was a significant difference in the proportion of CRSwNP with different endotypes. There were significant differences in peripheral blood eosinophils, cerebrovascular disease, and unilateral and bilateral nasal polyps among CRSWNP patients with different cytological types.

CONCLUSIONS

Mixed CRSwNP and eosinophilic CRSwNP are the most common, while neutrophilic CRSWNP is the least common. Eosinophilic CRSwNP is more common in bilateral nasal polyps, with a high recurrence rate and a high probability of olfactory dysfunction. Neutrophilic CRSwNP is more common in elderly patients with cardiovascular and cerebrovascular diseases. Compared with total serum IgE, the percentage of eosinophils in peripheral blood is more helpful for the diagnosis of eosinophilic CRSwNP.

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.

Risk factors investigation for different outcomes between unilateral and bilateral chronic rhinosinusitis with nasal polyps patients

BACKGROUND

Studies involving chronic rhinosinusitis with nasal polyps (CRSwNP) have mostly focused on bilateral cases, making unilateral CRSwNP inadequately recognized. This study examined the differences in clinical characteristics, outcomes, and risk factors for poor outcomes between unilateral and bilateral CRSwNP to facilitate a better assessment in the two groups.

METHODS

Demographic information, tissue and blood cells, endoscopic scores, Lund-Mackay scores, recurrence rates, and disease control conditions were compared between 310 unilateral and 596 bilateral CRSwNP patients. Furthermore, the stepwise regression multivariate Cox proportional hazard models were performed to generate risk factors for poor outcomes in the two groups.

RESULTS

Bilateral cases exhibited higher rates of smoking, AR, and asthma comorbidities, along with higher numbers of tissue eosinophils and blood inflammatory cells when compared to unilateral patients. Endoscopic nasal polyp score, total computed tomography (CT) score (with scores for each sinus cavity), and adjusted CT scores were significantly higher in the bilateral group, except for a markedly higher adjusted maxillary score in the unilateral group. Furthermore, significantly higher proportions of bilateral patients experienced nasal polyp recurrence, uncontrolled status, and most disease control-related symptoms at follow-up. The primary risk factors for poor outcomes were asthma, tissue eosinophils, and total CT score in the bilateral group and blood basophils in the unilateral group.

CONCLUSIONS

Bilateral CRSwNP patients experience worse disease severity and outcomes than their unilateral counterparts. Primarily, asthma, tissue eosinophils, and total CT score were risk factors for poor outcomes in bilateral CRSwNP patients, with blood basophils in unilateral cases.

Anti-IL-4Rα monoclonal antibody (CM310) in patients with chronic rhinosinusitis with nasal polyps (CROWNS-2): Rationale and design of a multicenter, randomized, double-blind, placebo-controlled, parallel-group study

Background

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogeneous disease that affects a large proportion of the global population. The treatment of CRSwNP, especially eosinophilic CRSwNP (ECRSwNP), has always been of great obstacle. Our previous phase 2 trial showed that CM310, a monoclonal antibody that targets interleukin-4 receptor alpha, was both safe and effective in reducing the size of nasal polyps, improving symptom scores, and increasing the quality of life for those with severe ECRSwNP.

Objective

This phase 3 trial aims to evaluate the efficacy, safety, pharmacokinetic, pharmacodynamic, and immunogenicity of CM310 in participants with CRSwNP.

Result

The CROWNS-2 is a multicenter, randomized, double-blind, placebo-controlled, parallel-group, phase 3 trial. The study consisted of a screening/run-in period (up to 4 weeks), a treatment period (24-week double-blind treatment period plus 28-week maintenance period), and a safety follow-up period (8 weeks). The study planned to enroll 180 participants with CRSwNP (at least 60% of ECRSwNP) to receive CM310 300 mg/placebo every 2 weeks (Q2W) subcutaneously for a total of 12 doses in double-blind treatment period and 300 mg CM310 Q2W subcutaneously for a total of 14 doses in maintenance period. Enrolled participants continued to use mometasone furoate nasal spray throughout the study. The primary endpoints are a change from baseline in nasal polyp score and nasal congestion score at week 24 between CM310 and placebo in both ECRSwNP and CRSwNP.

Conclusion

The CROWNS-2 is a multicenter, randomized, double-blind, placebo-controlled, parallel-group, phase 3 clinical study to evaluate the efficacy and safety of CM310 in patients with CRSwNP.

Trial registration

NCT05436275.

Systematic Review of Long Term Sinonasal Outcomes in CRSwNP after Endoscopic Sinus Surgery: A call for Unified and Standardized Criteria and Terms

PURPOSE OF REVIEW

To present current evidence in long-term (> 5 years) results after endoscopic sinus surgery (ESS) focusing on Patients Reported Outcome Measures (PROMs) and other sinonasal outcomes while assessing the role of ESS in the treatment of CRSwNP, and identifying outcomes which affect the results of ESS and defining recommendations for future studies.

RECENT FINDINGS

Long-term results of ESS in CRSwNP can be branched in PROMs and other objective measurements. Despite the heterogeneity of reported outcomes make it difficult to perform comparisons and meta-analysis, ESS improves PROMs, including symptoms, QOL and olfaction. Objectives outcomes such as NPS, LMS, type of surgery, or recurrence and revision surgery don't have a clear role in long-term results. Clustering patients suggest asthma, N-ERD, allergy, eosinophil count and IL-5 could have a role in predicting recurrence and severe disease. Long-term studies of CRSwNP treated with ESS are scarce. There is a significant need to standardize the report of results. The use of tools as SNOT-22, NPS, validated smell tests, defined criteria for disease recurrence and control and ESS extension in a unified systematic way could allow better comparisons between treatments in the new era of biologics.

[Chronic rhinosinusitis with nasal polyposis : A retrospective analysis of therapeutic approaches in 463 patients]

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease, the treatment of which has undergone significant changes in recent years. In addition to surgical approaches, topical and systemic steroids, and adaptive acetylsalicylic acid (ASA) desensitization, three specific antibodies have complemented the therapeutic portfolio since 2019.

METHODS

A retrospective evaluation of all patients who presented as outpatients for the first time due to CRSwNP in 2007 and 2008 (collective A) and 2017 and 2018 (collective B) was performed, up to and including June 2023.

RESULTS

The clinical courses of 463 patients (mean age 49.1 years, range 5-82 years; 65.9% male) were included in the analysis. Conservative treatment with nasal corticosteroids started before initial presentation was more frequent in collective B (collective A 43.9% vs. collective B 72.2%). In 278 of the 463 patients (60%; A: 62%, B: 58%), at least one operation on the nasal sinuses had been performed after initial presentation; in 101 of these patients (36.3%) recurrent polyposis (within mean follow-up of 2.4 years) required further treatment. The indication for ASA provocation/desensitization was applied less frequently in collective B, also due to a high discontinuation rate (at least 38%) of the maintenance therapy. Of the total cohort, 16 patients (3.5%; A: n = 8, B: n = 8) were meanwhile switched to antibody therapy at recurrence.

CONCLUSION

A step-by-step guideline-orientated approach is recommended in the treatment of CRSwNP. Systemic antibodies as an add-on to nasal corticosteroids are a relatively new therapeutic option for treatment-refractory CRSwNP, which reduces the indication for ASA desensitization, which is associated with a relatively high incidence of side effects and poor compliance.

The value of combined detection of specific immunoglobulin E, interleukin-6 and regulatory T cells in predicting the risk of postoperative recurrence in patients with eosinophilic chronic rhinosinusitis and nasal polyps

Background

To investigate the predictive value of specific immunoglobulin E (sIgE), interleukin-6 (IL-6) and regulatory T cells (Treg) on the risk of postoperative recurrence in patients with eosinophilic Chronic rhinosinusitis with nasal polyps (EcRswNP).

Methods

A total of 198 patients with EcRswNP collected to our Hospital from January 2019 to December 2021 were selected as the research subjects. All patients underwent functional endoscopic sinus surgery. The patients were selected to recurrence group (RG, n = 48) and nonrecurrence group (NRG, n = 150) on the basis of the recurrence after 1 year of follow-up. The related factors of postoperative recurrence of EcRswNP were analyzed. The ROC was used to analyze the dangerous of sIgE, IL-6 and Treg in predicting postoperative recurrence of EcRswNP patients.

Results

The proportion of asthma patients, nasal congestion VAS score, and peripheral blood Eos% content in the RG exceeded that in the NRG, and the Organization Neu % and peripheral blood Neu% levels were less than those in the NRGp (P all < 0.05). The serum sIgE and serum IL6 in the RG were higher than those in the NRG, while the level of peripheral blood Treg was lower than that in the NRG (P < 0.05). Logistic regression analysis showed that high levels of serum sIgE, serum IL-6 and low Treg levels were risk factors for postoperative recurrence (P < 0.05). ROC showed that the AUC of peripheral blood sIgE level, IL-6 and Treg levels alone in predicting the dangerous of postoperative recurrence in patients with EcRswNP were 0.786, 0.707 and 0.636, respectively (all P < 0.05); The AUC of combined prediction of peripheral blood sIgE, IL-6 and Treg levels for postoperative recurrence dangerous in patients with EcRswNP was 0.973, indicating that the efficacy of jointed prediction was exceed than that of single prediction (P < 0.05).

Conclusions

The high levels of sIgE, IL6 and low Treg levels in patients with EcRswNP before operation will increase the risk of postoperative recurrence, which is a risk factor affecting postoperative recurrence, and the three indicators have good predictive value for predicting postoperative recurrence in patients with EcRswNP, and the combination of the three indicators has better value in predicting postoperative recurrence.

CD4+ Foxp3+ Regulatory T-cells in Modulating Inflammatory Microenvironment in Chronic Rhinosinusitis with Nasal Polyps: Progress and Future Prospect

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a subtype of chronic rhinosinusitis (CRS) characterized by the presence of nasal polyps (NP) in the paranasal mucosa. Despite the complex etiology, NP is believed to result from chronic inflammation. The long-term aftermath of the type 2 response is responsible for symptoms seen in NP patients, i.e. rhinorrhea, hyposmia, and nasal obstruction. Immune cellular tolerogenic mechanisms, particularly CD4 + Foxp3 + regulatory T cells (Tregs), are crucial to curtail inflammatory responses. Current evidence suggests impaired Treg activity is the main reason underlying the compromise of self-tolerance, contributing to the onset of CRSwNP. There is compelling evidence that tumor necrosis factor 2 (TNFR2) is preferentially expressed by Tregs, and TNFR2 is able to identify the most potent suppressive subset of Tregs. Tumor necrosis factor (TNF)-TNFR2 interaction plays a decisive role in the activation and expansion of Tregs. This review summarizes current understanding of Tregs biology, focusing on the discussion of the recent advances in the study of TNF-TNFR2 axis in the upregulation of Treg function as a negative feedback mechanism in the control of chronic inflammation. The role of dysregulation of Tregs in the immunopathogenesis of CRSwNP will be analyzed. The future perspective on the harnessing Tregs-mediated self-tolerant mechanism in the management of CRSwNP will be introduced.

Association Between Serum Amyloid A Expression and Disease Control after Endoscopic Sinus Surgery in Patients With Chronic Rhinosinusitis With Nasal Polyps

OBJECTIVE

Our previous study revealed that serum amyloid A (SAA) levels in polyp tissues could serve as a biomarker for the prediction of corticosteroid insensitivity in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). However, their association with disease control status in the patients after endoscopic sinus surgery remains to be assessed.

METHODS

Polyp tissues and control uncinate process mucosa were collected from 48 patients with CRSwNP and 10 healthy control subjects. SAA expression was examined using immunohistochemistry and enzyme-linked immunosorbent assay. Receiver operating characteristic (ROC) curves were performed to determine the predictive value of SAA in nasal polyps. The clinical characteristics of 2 CRSwNP subtypes (SAAhigh and SAAlow) were evaluated.

RESULTS

The SAA expression levels in polyp tissues were significantly elevated both in non-eosinophilic and eosinophilic CRSwNP as compared to the healthy controls. In patients with CRSwNP, the tissue SAA level was significantly higher in the disease-controlled patients than those of the partly controlled and uncontrolled. ROC curve analysis revealed that a cut-off value of 114.9 ng/mL for the tissue SAA level predicted the patients with disease-controlled status with 93.33% sensitivity and 63.64% specificity (AUC = .8727, P < .001). Furthermore, The SAAhigh subgroup showed higher tissue eosinophil numbers and percentage of the disease-controlled patients compared to the SAAlow subgroup.

CONCLUSIONS

Our findings suggest that measurements of SAA in polyp tissues may provide useful information for evaluating CRSwNP conditions, especially identifying the CRSwNP patients with disease-controlled status after endoscopic sinus surgery.

SerpinB3/B4 Abates Epithelial Cell-Derived CXCL8/IL-8 Expression in Chronic Rhinosinusitis with Nasal Polyps

Background

Serine proteinase inhibitors, clade B, member 3 (SerpinB3) and B4 are highly similar in amino acid sequences and associated with inflammation regulation. We investigated SerpinB3 and B4 expression and their roles in chronic rhinosinusitis with nasal polyps (CRSwNP).

Methods

The expression of SerpinB3 and B4 in nasal mucosa tissues, brush cells, and secretions from CRSwNP patients was measured, and their regulation by inflammatory cytokines were investigated. Their functions were also analyzed using air-liquid interface (ALI)-cultured primary human nasal epithelial cells (HNECs) and transcriptomic analysis.

Results

Both SerpinB3 and B4 expression was higher in nasal mucosa, brush cells, and secretions from eosinophilic (E) CRSwNP and nonECRSwNP patients than in healthy controls. Immunofluorescence staining indicated that SerpinB3 and B4 were primarily expressed in epithelial cells and their expression was higher in CRSwNP patients. SerpinB3 and B4 expression was upregulated by interleukin-4 (IL-4), IL-5, IL-6, and IL-17a. Transcriptomic analysis identified differentially expressed genes (DEGs) in response to recombinant SerpinB3 and B4 stimulation. Both the DEGs of SerpinB3 and B4 were associated with disease genes of nasal polyps and inflammation in DisGeNET database. Pathway enrichment indicated that downregulated DEGs of SerpinB3 and B4 were both enriched in cytokine-cytokine receptor interactions, with CXCL8 as the hub gene in the protein-protein interaction networks. Furthermore, CXCL8/IL-8 expression was downregulated by recombinant SerpinB3 and B4 protein in ALI-cultured HNECs, and upregulated when knockdown of SerpinB3/B4.

Conclusion

SerpinB3/B4 expression is upregulated in nasal mucosa of CRSwNP patients. SerpinB3/B4 may play an anti-inflammatory role in CRSwNP by inhibiting the expression of epithelial cell-derived CXCL8/IL-8.

Analysis of the Construction of a Predictive Model for Eosinophilic Chronic Rhinosinusitis

Purpose

This study aimed to determine indices to diagnose and predict eosinophilic chronic rhinosinusitis (ECRS) during the initial clinic visit.

Patients and Methods

We retrospectively analyzed 116 patients with chronic rhinosinusitis who underwent endoscopic sinus surgery and were classified according to the postoperative pathological diagnosis. General data and various clinical indicators were analyzed, and indicators with statistically significant differences between groups were further incorporated into a multivariate logistic regression to establish a comprehensive prediction model. The receiver operating characteristic (ROC) curve was used to compare the two significant valuable single factors from previous studies, the difference in CT scores between the ethmoid sinus and the sum difference of the maxillary sinus (EM difference) and the absolute value of peripheral blood eosinophil (bEOS), with a comprehensive prediction model.

Results

There were significant differences in history of allergic asthma (p < 0.001), visual analog scale (VAS) score (p=0.005), sino-nasal outcome test-22(SNOT-22) scale score (p=0.004), Lund-Mackay scale score (p=0.017), EM difference (p=0.002), percentage of bEOS (%)(p=0.001), and absolute value of bEOS (×109/L) (p=0.000) between the two groups (p< 0.05). The history of allergic disease, VAS and bEOS were screened out and included in the comprehensive prediction model. The area under the curve (AUC) of the comprehensive prediction model (0.804)> the AUC of the absolute value of the bEOS (0.764)>the AUC of the EM difference (0.655). The AUC of the EM difference and the comprehensive prediction model were statistically different (P=0.025). There was no statistical difference between the absolute value of bEOS and the AUC of the comprehensive prediction model.

Conclusion

The comprehensive prediction model covering the three aspects of allergic asthma history, VAS score, and bEOS count had the highest AUC compared to the other predictors and had good predictive power for the diagnosis of ECRS.

Interleukin-19 enhances eosinophil infiltration through upregulation of epithelium-derived RANTES expression via the ERK/NF-κB signalling pathway in patients with eosinophilic CRSwNP

BACKGROUD

The recurrence rate of chronic rhinosinusitis with nasal polyps (CRSwNP) is positively correlated with eosinophil infiltration. Increased interleukin (IL)-19 and eosinophil chemokine RANTES levels have been reported in patients with CRSwNP. This study aimed to clarify the role of IL-19 in mediating RANTES expression and eosinophilic infiltration in eosinophilic CRSwNP (Eos CRSwNP).

METHODS

Nasal tissue samples were obtained from patients with CRSwNP and controls. The expression of IL-19, its receptors, ECP, and RANTES in tissues was investigated. Primary human nasal epithelial cells (HNECs) and nasal polyp tissue blocks were cultured, then stimulated by IL-19; ERK phosphorylation, NF-κB pathway activation, RANTES level, eosinophils migration and infiltration were detected using RT-qPCR, ELISA, western blotting, HE, immunohistochemistry, immunofluorescence staining, confocal microscopy, and transwell migration assay.

RESULTS

The expression of IL-19 and its receptors (IL-20R1/IL-20R2), eosinophil cationic protein, and RANTES in nasal tissues from patients with Eos CRSwNP was significantly increased compared to that in non-Eos CRSwNP and control subjects. IL-19 co-localized with RANTES in nasal tissues and significantly elevated RANTES expression in HNECs. IL-19-blocking antibody and siRNA knockdown of IL-20R1 ameliorated the effect of IL-19 on RANTES secretion in HNECs. Moreover, IL-19-induced RANTES upregulation was associated with the activation of the ERK and NF-κB pathways. NF-κB activation was mediated by the ERK pathway in IL-19-treated HNECs, and IL-19 enhanced eosinophil infiltration in nasal polyp tissue blocks.

CONCLUSIONS

Our findings indicate that IL-19 promotes RANTES expression via the ERK/NF-κB pathway in HNECs and is implicated in eosinophil infiltration in patients with Eos CRSwNP.

Interaction of eosinophilic and neutrophilic inflammation in patients with chronic rhinosinusitis

PURPOSE OF REVIEW

In the past year, the endotype of chronic rhinosinusitis (CRS) has been studied from a new perspective. Eosinophilic and neutrophilic inflammation are not independent processes in the pathogenesis of CRS. In this review, we will focus on recent research on mixed eosinophilic-neutrophilic inflammation in CRS and discuss the mechanism and potential treatments.

RECENT FINDINGS

Traditionally, patients with eosinophilic CRS (ECRS) present with severe clinical manifestations, comorbidities, and a higher recurrence rate. Recent studies have found that approximately 40% of patients with ECRS present with neutrophilic infiltration, while patients with predominantly eosinophilic infiltration along with neutrophilic inflammation present with more complex inflammation, clinical manifestations and exhibit refractory characteristics.

SUMMARY

The complex inflammatory profile and refractory clinical characteristics of mixed eosinophilic-neutrophilic inflammation in CRS are current challenges for clinicians. We summarize the features of eosinophilic and neutrophilic inflammation and current studies on the mechanisms of mixed eosinophilic-neutrophilic inflammation and suggest potentially effective therapeutic methods. We hope that this review will help with determining precise treatment options for patients.

Outcomes of endoscopic sinus surgery in patients with central compartment atopic disease

Background

Central compartment atopic disease (CCAD) is a subtype of chronic rhinosinusitis (CRS). Research focusing on the endoscopic sinus surgery (ESS) outcomes of CCAD is limited. This study aimed to evaluate the outcomes of ESS in CCAD and compared to 2 following subtypes: chronic rhinosinusitis with nasal polyps (CRSwNP) and concomitant polypoid disease in the central compartment (CRSwNP/CC) and CRSwNP not otherwise specified (CRSwNP NOS).

Methods

This case-control study enrolled patients with bilateral CRSwNP who underwent ESS and had at least 1 year of follow-up. Patients were classified into CCAD, CRSwNP/CC, and CRSwNP NOS. The demographic data, preoperative disease severity, and surgery outcomes, including CRS control status, endoscopic score, and symptom scores at 1 year postoperatively, were collected. We defined well controlled and partly controlled as appropriate disease control.

Results

This study screened 259 patients and enrolled 138 patients with complete medical records and 1-year follow-up (CCAD N = 51, CRSwNP/CC N = 55, CRSwNP NOS N = 32). Among them, appropriate disease control was achieved in 84.3% of patients (43/51) in the CCAD group, 69.1% (38/55) in the CRSwNP/CC group, and 93.7% (30/32) in the CRSwNP NOS group (P = 0.029). Then we performed post-hoc analysis using appropriate disease control and uncontrolled. There was a significant difference between CRSwNP/CC and CRSwNP NOS (P = 0.007), but no significant difference compared CCAD group to CRSwNP/CC group (P = 0.065) and CRSwNP NOS group (P = 0.199). There were significant differences in endoscopic E-score among groups (P < 0.001). In post-hoc analysis, we found that CRSwNP/CC (Median [IQR], 33.32 [42.14]) had a significantly worse E-score than CCAD (8.33 [16.67]) and CRSwNP NOS (4.17 [8.30]). Also, postoperative olfactory visual analog scale (VAS) scores significantly differed among groups (P = 0.043). However, post-hoc analysis showed no difference between any 2 groups. There were no differences in postoperative VAS scores of obstruction (P = 0.159), rhinorrhea (P = 0.398), and headache/facial pain (P = 0.092).

Conclusion

Most CCAD patients had good surgical outcomes 1 year after surgery. Meanwhile, the CRSwNP/CC group had the fewest patients under appropriate disease control.

Diverse Endotypes of Chronic Rhinosinusitis and Clinical Implications

Chronic rhinosinusitis (CRS) is a highly heterogeneous disease characterized by inflammation in the nasal and sinus mucosa. The CRS phenotypes, based on the presence or absence of nasal polyps, are known as CRS with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). However, this classification has limitations in fully capturing the mechanisms and clinical manifestations of CRS. To address the heterogeneity of CRS, there has been a growing focus on classifying the condition into distinct endotypes. Endotype classification involves grouping patients based on specific molecular, immunological, and clinical characteristics, allowing for more personalized and targeted treatment approaches.This review delves into the current state of endotype classifications for CRS. It explores the role of geographic factors, microbiome, and subphenotype in shaping different endotypes. Additionally, the review examines how various clinical features are associated with specific endotypes, providing valuable insights into tailoring treatment options for better outcomes and transitions between different endotypes.Overall, this review offers a comprehensive and up-to-date perspective on the intricate realm of CRS endotype classifications. By unraveling the molecular and clinical intricacies, this review lays the foundation for more precise, effective, and individualized treatment strategies in the management of CRS.

The SMYD3-dependent H3K4me3 status of IGF2 intensifies local Th2 differentiation in CRSwNP via positive feedback

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogeneous and common upper airway disease divided into various inflammatory endotypes. Recent epidemiological findings showed a T helper 2 (Th2)-skewed dominance in CRSwNP patients. Histone modification alterations can regulate transcriptional and translational expression, resulting in abnormal pathogenic changes and the occurrence of diseases. Trimethylation of histone H3 lysine 4 (H3K4me3) is considered an activator of gene expression through modulation of accessibility for transcription, which is closely related to CRSwNP. H3K4me3 levels in the human nasal epithelium may change under Th2-biased inflammatory conditions, resulting in exaggerated local nasal Th2 responses via the regulation of naïve CD4+ T-cell differentiation. Here, we revealed that the level of SET and MYND domain-containing protein 3 (SMYD3)-mediated H3K4me3 was increased in NPs from Th2 CRSwNP patients compared with those from healthy controls. We demonstrated that SMYD3-mediated H3K4me3 is increased in human nasal epithelial cells under Th2-biased inflammatory conditions via S-adenosyl-L-methionine (SAM) production and further found that the H3K4me3high status of insulin-like growth factor 2 (IGF2) produced in primary human nasal epithelial cells could promote naïve CD4+ T-cell differentiation into Th2 cells. Moreover, we found that SAM production was dependent on the c-Myc/methionine adenosyltransferase 2A (MAT2A) axis in the nasal epithelium. Understanding histone modifications in the nasal epithelium has immense potential utility in the development of novel classes of therapeutics targeting Th2 polarization in Th2 CRSwNP. Video Abstract.

Differences in Clinical and Immunological Characteristics According to the Various Criteria for Tissue Eosinophilia in Chronic Rhinosinusitis With Nasal Polyps

OBJECTIVES

Several criteria exist for classifying chronic rhinosinusitis with nasal polyps (CRSwNP) as eosinophilic or non-eosinophilic. This study attempted to evaluate several criteria for defining eosinophilic CRSwNP from clinical and immunological perspectives.

METHODS

A cohort of 84 patients (73 patients with CRSwNP and 11 control patients) was retrospectively analyzed. Patients were divided into eosinophilic and non-eosinophilic CRSwNP based on four different criteria: eosinophils (EOS) accounting for more than 20% of the total inflammatory cells; ≥70 EOS per high-power field (HPF); >55 EOS/HPF; and ≥10 EOS/HPF. Preoperative clinical characteristics, the immunological profiles of 14 cytokines from nasal tissue, and postoperative outcomes were compared between eosinophilic and non-eosinophilic CRSwNP based on each criterion. These criteria were immunologically validated by using 14 cytokines to predict the performance of tissue eosinophilia with a random forest model.

RESULTS

Patients with eosinophilic CRSwNP were significantly older when the criterion of ≥10 EOS/HPF or EOS >20% was used. The number of patients with aspirin intolerance was significantly higher in eosinophilic CRSwNP based on the criterion of EOS >20%. From an immunological perspective, non-type 2 inflammatory cytokines were significantly higher in non-eosinophilic CRSwNP with the criterion of EOS >20% of the total inflammatory cells. In addition, the criterion of EOS >20% of the total inflammatory cells resulted in the best prediction of eosinophilic CRSwNP, with an accuracy of 88.10% and area under the curve of 0.94.

CONCLUSION

Clinical and immunological characteristics were different between eosinophilic and non-eosinophilic CRSwNP depending on a variety of criteria, and the.

RESULTS

of this study should be taken into account when choosing the criterion for defining eosinophilic CRSwNP and interpreting the data accordingly.

IL-21 induces pyroptosis of Treg cells via Akt-mTOR-NLRP3-caspase 1 axis in eosinophilic chronic rhinosinusitis

BACKGROUND

Regulatory T (Treg) cells, which prevent inflammation-induced eosinophil infiltration, are deficient in nasal polyps (NPs) in patients with eosinophilic chronic rhinosinusitis (ECRS). It is concomitant with loss of Foxp3 after certain inflammatory stimuli.

OBJECTIVE

We sought to determine the inflammatory cytokines involved in inducing the loss of Treg cells in NPs.

METHODS

The abundance of cytokines in ECRS patients or mice were tested using ELISA, immunochemistry, immunofluorescence, quantitative reverse transcription PCR (qPCR), and/or flow cytometry. Expression of eosinophil cationic protein (ECP), CD4+ T cells, IL-4, and IL-17A and eosinophils in nasal mucosa of mouse model was investigated by immunochemistry, immunofluorescence, and hematoxylin and eosin staining. The percentage and death of induced Treg (iTreg) cells, source of IL-21 in NPs from ECRS and non-ECRS patients, and abundance of different systemic phenotypes of CD4+ T cells in a mouse model were studied by flow cytometry. Western blot analysis, scanning, and transmission electronic microscopy were used to detect pyroptosis of iTreg cells.

RESULTS

IL-21 was highly expressed in nasal mucosa of ECRS patients and mice, causing pyroptosis and preventing development of iTreg cells in vitro. The elevated IL-21 in NPs from ECRS patients was mainly produced by CD3+ T cells, including T follicular helper, T peripheral helper, TH2, and TH17 cells and CD3+CD4- T cells. T peripheral helper cells and CD3+CD4- T cells were the predominant source of IL-21 in NPs from non-ECRS patients. Blocking IL-21/IL-21R signaling significantly reduced the number of eosinophils and CD4+ T cells along with ECP, IL-4, and IL-17A expression in the nasal mucosa of ECRS mice. It also increased Treg cell percentage and systemically decreased TH2 and TH17 ratios. Akt-mTOR inhibition prevented IL-21-induced pyroptosis in human and mouse iTreg cells.

CONCLUSION

Elevated IL-21 drives pyroptosis and prevents Treg cell development in ECRS patients. IL-21 induced pyroptosis via activating Akt-mTOR-NLRP3-caspase 1 signaling.

Use of peripheral blood eosinophils to guide post-operative glucocorticoid therapy in patients with chronic rhinosinusitis with nasal polyps: a randomised, controlled trial

OBJECTIVE

This study aimed to explore the utility of the eosinophil percentage in peripheral blood for guiding post-operative glucocorticoid therapy in patients with chronic rhinosinusitis with nasal polyps.

METHODS

Forty-four patients with chronic rhinosinusitis with nasal polyps underwent functional endoscopic sinus surgery and were randomly divided into two groups. Patients in the standard treatment group used oral and nasal spray glucocorticoids. In the biomarker treatment group, patients with peripheral blood eosinophil percentage values less than 3.05 per cent did not receive glucocorticoid treatment, whereas patients with values 3.05 per cent or above were part of the standard treatment group. Visual Analogue Scale, Sino-Nasal Outcome Test-22 scores, endoscopic Lund-Kennedy scores, eosinophils, interleukin-5 and eosinophil cationic protein in peripheral blood, and nasal secretions were measured.

RESULTS

After functional endoscopic sinus surgery, the Visual Analogue Scale, Sino-Nasal Outcome Test-22 and Lund-Kennedy scores were significantly reduced in both groups; there were no significant differences in those indicators between the groups during the three follow-up visits.

CONCLUSION

Peripheral blood eosinophil percentage offers a potential biomarker to guide post-operative glucocorticoid therapy in patients with chronic rhinosinusitis with nasal polyps.

Diagnostic value of myeloperoxidase and eosinophil cationic protein in nasal secretions for endotypes of chronic rhinosinusitis

OBJECTIVES

To explore associations between inflammatory endotypes and clinical presentations in CRS. To investigate the value of secretions myeloperoxidase (MPO) and eosinophilic cationic protein (ECP) detections in the diagnosis of endotypes of chronic rhinosinusitis (CRS), so as to provide guidance for the clinical application of MPO and ECP detection in secretions.

METHODS

We collected clinical symptom scores from patients with CRS and examined the differences between endotypes in clinical features. Patients' nasal secretions and polyps (or middle turbinate for control) were collected and their NEU number, EOS%, MPO and ECP levels were measured. Correlation analysis was performed for these biomarkers in secretions and tissues, respectively. Receiver operating characteristic curves were used to assess the predictive potential of the biomarkers mentioned above in nasal secretions.

RESULTS

Patients with Eos+Neu+ and Eos+Neu-CRS scored highest in most clinical symptom scores, while Eos-Neu+ and Eos-Neu-CRS scored lowest. Correlation analysis showed that tissues NEU number was correlated with NEU number and MPO level in nasal secretions (R = 0.4088; 0.6613); tissues EOS % was correlated with EOS% and ECP level in nasal secretions (R = 0.2344; 0.5774). To diagnose Neu+CRS, the highest area under the curve (AUC) (0.8961) was determined for MPO in secretions; the highest AUC (0.7400) was determined for NEU number in secretions. To diagnose Eos+Neu-CRS from Eos-Neu-CRS in Neu-CRS, the highest AUC (0.8801) was determined for ECP in secretions.

CONCLUSIONS

Clinical presentations are directly associated with CRS endotypes. Measurement of MPO and ECP in nasal secretions is useful for the endotypes diagnosis of CRS.

Prognostic factors for post-operative outcomes in chronic rhinosinusitis with nasal polyps: a systematic review

INTRODUCTION

Chronic rhinosinusitis with nasal polyps (CRSwNP) has a high recurrence rate after surgery despite the availability of medical treatments. Multiple clinical and biological factors have been associated with poor post-operative outcomes in patients with CRSwNP. However, these factors and their prognostic values have not yet been extensively summarized.

AREAS COVERED

This systematic review included 49 cohort studies exploring the prognostic factors for post-operative outcomes in CRSwNP. A total of 7802 subjects and 174 factors were included. All investigated factors were classified into three categories according to their predictive value and evidence quality, of which 26 factors were considered plausible for post-operative outcome prediction. Previous nasal surgery, ethmoid-to-maxillary (E/M) ratio, fractional exhaled nitric oxide, tissue eosinophil count or percentage, tissue neutrophil count, tissue IL-5, tissue eosinophil cationic protein, and CLC or IgE in nasal secretion provided more reliable information for prognosis in at least two studies.

EXPERT OPINION

Exploring predictors through noninvasive or minimally invasive methods for specimen collection is recommended for future work. Models combining multiple factors must be established, as no single factor is effective for the whole population.

Efficacy and safety of CM310 in severe eosinophilic chronic rhinosinusitis with nasal polyps (CROWNS-1): a multicentre, randomised, double-blind, placebo-controlled phase 2 clinical trial

Background

Severe eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) remains the most relapsed subtype of uncontrolled CRSwNP. CM310, a humanised anti-interleukin (IL)-4 receptor alpha monoclonal antibody, inhibits IL-4 and IL-13 signaling which underlying eosinophilic inflammation. This study aims to evaluate the efficacy and safety of CM310 in patients with severe ECRSwNP.

Methods

A multicentre, randomised, double-blind, and placebo-controlled phase 2 clinical trial was conducted. 56 eligible adult patients with severe ECRSwNP were randomised 1:1 to receive subcutaneously either CM310 (300 mg) or placebo every 2 weeks under the background therapy of mometasone furoate nasal spray (MFNS) for 16 weeks, with 8 weeks of follow-up. Coprimary endpoints included the changes from baseline in nasal polyp score (NPS) and nasal congestion score (NCS) at week 16. Key secondary endpoints included sinus Lund-Mackay CT score, change in sinus volume occupied by disease, University of Pennsylvania Smell Identification Test score, 22-item Sino-nasal Outcome Test score, and total symptom score. Safety, pharmacodynamics, and changes in type 2 inflammation biomarkers were assessed. This study is registered with ClinicalTrials.gov, NCT04805398.

Findings

Between April 6, 2021, and March 18, 2022, 27 patients respectively in both the CM310 and placebo groups completed the study. Findings suggested that CM310 improved the coprimary efficacy endpoints of decreasing nasal polyp size and alleviating nasal congestion compared with the placebo. Least squares (LS) mean differences (CM310 vs placebo) of change from baseline in NPS and NCS at week 16 were -2.1 (95% CI -2.9, -1.4; p < 0.0001) and -0.9 (95% CI -1.4, -0.5; p < 0.0001), respectively. Sinus CT scan revealed that Lund-Mackay CT score (LS mean difference [95% CI] -7.6, [-9.4, -5.8]; p < 0.0001) and sinus volume occupied by disease (LS mean difference [95% CI] -37%, [-47%, -28%]; p < 0.0001) were significantly improved with CM310 compared with placebo. In addition, CM310 significantly relieved the daily symptoms of patients with CRSwNP and improved their quality of life reflected by the improvements in the TSS (-2.6 [95% CI -3.5, -1.6]), UPSIT (10.4 [95% CI 6.8, 14.0]) and SNOT-22 score (-19.1 [95% CI -29.8, -8.5]). Compared with placebo, CM310 administration significantly reduced type 2-related biomarkers including the serum TARC and total IgE, and tissue eosinophils. The most common adverse events were upper respiratory tract infection, blood cholesterol increased, and tinnitus, but none were considered drug-related.

Interpretation

These findings support CM310 as an effective additional treatment option to the standard of care in patients with severe ECRSwNP.

Funding

KeyMed Biosciences (Chengdu) Limited.

Direct economic burden 1 year postoperation in Chinese adult patients with chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) remains a common and challenging clinical entity, and its economic burden has not been well described in China thus far.

METHODS

A total of 101 CRSwNP patients who underwent endoscopic sinus surgery were included to investigate direct costs in the first year post-surgery. Costs for outpatient visits, medication use, and examination costs were obtained from the Hospital Information System, and differences were compared between subgroups. Multiple linear regression analysis was adopted to investigate the main influencing factors on annual total direct costs for CRSwNP patients.

RESULTS

Ninety-two subjects completed the study. The individual mean total direct cost for a CRSwNP patient 1 year post-surgery was $742.4. The largest contributors were pharmacy costs ($580.2), followed by examination costs ($108.1) and outpatient visits ($54.1). Total direct costs were higher in subgroups of patients with uncontrolled clinical status, asthma comorbidity, and eosinophilic CRSwNP compared to their counterparts. The main influencing factors were clinical control status (P = 0.016) and asthma comorbidity (P = 0.035).

CONCLUSIONS

The individual mean total direct cost of CRSwNP in 1-year post-surgery was $742.4. Clinical control status and asthma comorbidity influence these costs and are therefore important in guiding health resources allocation for CRSwNP management.

Innovative treatments for severe uncontrolled chronic rhinosinusitis with nasal polyps

INTRODUCTION

In recent years, endotypes of chronic rhinosinusitis (CRS) based on the underlying immune mechanisms provided a better understanding of this heterogeneous disease and are frequently applied in diagnosis and treatment.

AREAS COVERED

In this manuscript, we aim to review novel treatment approaches for this often uncontrolled disease and highlight endotype-driven medical algorithms that could be beneficial in daily clinical practice.

EXPERT OPINION

With the development of endotyping and the mucosal inflammatory concept, several type 2-targeted biologics and surgical options are nowadays available for treating CRS. However, a better understanding based on clinical trials and real-life experience in daily practice is needed to optimize patient selection, biological drug selection, treatment duration, prediction, and long-term follow-up strategies. Indirect comparison analysis suggested that dupilumab might be the most effective biologic for treating CRS with nasal polyps, but the role and timing of surgery remain unclear. More real-life studies and comparative trials are needed for the optimal integration of biologics into clinical pathways in combination with established treatment approaches such as nasal and oral glucocorticosteroids and adequate surgery to provide long-term perspectives.

Machine learning method for the cellular phenotyping of nasal polyps from multicentre tissue scans

BACKGROUND

This study aimed to establish a convenient and accurate chronic rhinosinusitis evaluation platform CRSAI 1.0 according to four phenotypes of nasal polyps.

RESEARCH DESIGN AND METHODS

Tissue sections of a training (n = 54) and test cohort (n = 13) were sourced from the Tongren Hospital, and those for a validation cohort (n = 55) from external hospitals. Redundant tissues were automatically removed by the semantic segmentation algorithm of Unet++ with Efficientnet-B4 as backbone. After independent analysis by two pathologists, four types of inflammatory cells were detected and used to train the CRSAI 1.0. Dataset from Tongren Hospital were used for training and testing, and validation tests used the multicentre dataset.

RESULTS

The mean average precision (mAP) in the training and test cohorts for tissue eosinophil%, neutrophil%, lymphocyte%, and plasma cell% was 0.924, 0.743, 0.854, 0.911 and 0.94, 0.74, 0.839, and 0.881, respectively. The mAP in the validation dataset was consistent with that of the test cohort. The four phenotypes of nasal polyps varied significantly according to the occurrence of asthma or recurrence.

CONCLUSIONS

CRSAI 1.0 can accurately identify various types of inflammatory cells in CRSwNP from multicentre data, which could enable rapid diagnosis and personalized treatment.

A novel inflammatory endotype diagnostic model based on cytokines in chronic rhinosinusitis with nasal polyps

Background

Type 2 CRSwNP is characterized by severe symptoms, multiple comorbidities, longer recovery course and high recurrence rate. A simple and cost-effective diagnostic model for CRSwNP endotype integrating clinical characteristics and histopathological features is urgently needed.

Objective

To establish a clinical diagnostic model of inflammatory endotype in CRSwNP based on the clinical characteristics, pathological characteristics, and cytokines profile in the polyp tissue of patients.

Methods

A total of 244 participants with CRSwNP were enrolled at 2 different centers in China and Belgium from 2018 to 2020. IL-5 level of nasal polyp tissue was used as gold standard. Clinical characteristics were used to establish diagnostic models. The area under the receiver operating curve (AUC) was used to evaluate the diagnostic performance. The study was approved by the ethics board of the First Affiliated Hospital of Sun Yat-sen University ([2020] 302), and written informed consent was obtained from all subjects before inclusion.

Results

In total, 134 patients from China (training set) and 110 patients from Belgium (validation set) were included. The logistic regression (LR) model in predicting inflammatory endotype of CRSwNP showed the AUC of 83%, which was better than the diagnostic performance of machine learning models (AUC of 61.14%-82.42%), and single clinical variables. We developed a simplified scoring system based on LR model which shows similar diagnostic performance to the LR model (P = 0.6633).

Conclusion

The LR model in this diagnostic study provided greater accuracy in prediction of inflammatory endotype of CRSwNP than those obtained from the machine learning model and single clinical variable. This indicates great potential for the use of diagnostic model to facilitate inflammatory endotype evaluation when tissue cytokines are unable to be measured.

A review of current biomarkers in chronic rhinosinusitis with or without nasal polyps

INTRODUCTION

Chronic rhinosinusitis (CRS) is a heterogeneous disease with a variety of cellular and molecular pathophysiologic mechanisms. Biomarkers have been explored in CRS using various phenotypes, such as polyp recurrence after surgery. Recently, the presence of regiotype in CRS with nasal polyps (CRSwNP) and the introduction of biologics for the treatment of CRSwNP has indicated the importance of endotypes, and there is a need to elucidate endotype-based biomarkers.

AREAS COVERED

Biomarkers for eosinophilic CRS, nasal polyps, disease severity, and polyp recurrence have been identified. Additionally, endotypes are being identified for CRSwNP and CRS without nasal polyps using cluster analysis, an unsupervised learning technique.

EXPERT OPINION

Endotypes in CRS have still being established, and biomarkers capable of identifying endotypes of CRS are not yet clear. When identifying endotype-based biomarkers, it is necessary to first identify endotypes clarified by cluster analysis for outcomes. With the application of machine learning, the idea of predicting outcomes using a combination of multiple integrated biomarkers, rather than a single biomarker, will become mainstream.

Endotyping Difficult-to-Treat Chronic Rhinosinusitis with Nasal Polyps by Structured Histopathology

INTRODUCTION

This study aimed to identify the histopathologic characteristics associated with difficult-to-treat chronic rhinosinusitis with nasal polyps (CRSwNPs), enabling physicians to predict the risk of poor outcome after endoscopic sinus surgery (ESS).

METHODS

A prospective cohort study performed at the First Affiliated Hospital of Sun Yat-sen University between January 2015 and December 2018 with CRSwNP patients who underwent ESS. Polyp specimens were collected during surgery and were subjected to structured histopathological evaluation. Difficult-to-treat CRSwNPs were determined at 12-15 months post-operation according to the European Position Paper. Multiple logistic regression model was used to assess the association between histopathological parameters and the difficult-to-treat CRSwNP.

RESULTS

Among 174 subjects included in the analysis, 49 (28.2%) were classified with difficult-to-treat CRSwNP, which had higher numbers of total inflammatory cells, tissue eosinophils, and percentages of eosinophil aggregates and Charcot-Leyden crystals (CLC) formation but a lower number of interstitial glands than the nondifficult-to-treat CRSwNP. Inflammatory cell infiltration (adjusted OR: 1.017), tissue eosinophilia (adjusted OR: 1.005), eosinophil aggregation (adjusted OR: 3.536), and CLC formation (adjusted OR: 6.972) were independently associated with the difficult-to-treat outcome. Furthermore, patients with tissue eosinophil aggregation and CLC formation had an increasingly higher likelihood of uncontrolled disease versus those with tissue eosinophilia.

CONCLUSION

The difficult-to-treat CRSwNP appears to be characterized by increased total inflammatory infiltrates, tissue eosinophilia, eosinophil aggregation, and CLC formation in structured histopathology.

Individual exposure of ambient particulate matters and eosinophilic chronic rhinosinusitis with nasal Polyps: Dose-Response, mediation effects and recurrence prediction

PURPOSE

We evaluated the association between ambient particulate matter (PM) exposure and eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP), and predicted the CRSwNP recurrence risk using machine learning algorithms.

METHODS

In total, 1,086 patients with CRSwNP were recruited from nine hospitals in China during 2014-2019. The average annual concentrations of ambient PMs before surgery were assessed using satellite-based daily concentrations of PM_2.5 and PM₁₀ for a 1 × 1-km² area. Linear regression and logistic regression models were used to evaluate the associations of PM exposure with eosinophilia and risks of eosinophilic CRSwNPs. In addition, mediation effect analysis was used to validate the interrelationships of the aforementioned factors. Finally, machine learning algorithms were used to predict the recurrence risks of CRSwNPs.

RESULTS

There was a significantly increased risk of eosinophilic CRSwNPs with each 10 μg/m³ increase in PM_s, with odds ratios (ORs) of 1.039 (95% confidence interval [CI] = 1.007-1.073) for PM₁₀ and 1.058 (95% CI = 1.007- 1.112) for PM_2.5. Eosinophils had a significant mediation effect, which accounted for 52% and 35% of the relationships of CRSwNP recurrence with PM₁₀ and PM_2.5, respectively. Finally, we developed a naïve Bayesian model to predict the risk of CRSwNP recurrence based on PM exposure, inflammatory data, and patients' demographic factors.

CONCLUSIONS

Increased PM exposure is associated with an increased risk of eosinophilic CRSwNP in China. Therefore, patients with eosinophilic CRSwNP should reduce PM exposure to mitigate its harmful impacts.

Alterations of nasal microbiome in eosinophilic chronic rhinosinusitis

BACKGROUND

Exposure to microbes may be important in the development of chronic rhinosinusitis (CRS). Dysbiosis of the nasal microbiome is considered to be related to CRS with nasal polyps (CRSwNP). The link between the nasal microbiota and eosinophilic CRSwNP (eCRSwNP) has rarely been studied.

OBJECTIVE

The aim of this study was to rigorously characterize nasal dysbiosis in a cohort of patients with eCRSwNP and compare the nasal microbiomes of these patients with those of healthy controls (HCs).

METHODS

We performed a cross-sectional study of 34 patients with eCRSwNP, 10 patients without CRSwNP, and 44 HCs by using 16S rRNA gene sequencing. An independent cohort of 14 patients with eCRSwNP, 9 patients without CRSwNP, and 11 HCs was used to validate the results.

RESULTS

Compared with the nasal microbiome of healthy controls, the nasal microbiome of patients with eCRSwNP was characterized by higher α-diversity (Shannon and Chao1 index) and a distinct composition of microbes. Notably, the distinct differences in microbial composition between patients with eCRSwNP and HCs were significantly correlated with eCRSwNP disease status. Furthermore, in a diagnostic model generated by using these differences, a combination of 15 genera could be used to distinguish patients with eCRSwNP from HCs, with an area under the curve of approximately 0.8 in both the exploration and validation cohorts.

CONCLUSION

Our study establishes the compositional alterations in the nasal microbiome in eCRSwNP and suggests the potential for using the nasal microbiota as a noninvasive predictive classifier for the diagnosis of eCRSwNP.

Deep learning radiomics-based preoperative prediction of recurrence in chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is characterized by poor prognosis and propensity for recurrence even after surgery. Identification of those CRS patients with high risk of relapse preoperatively will contribute to personalized treatment recommendations. In this paper, we proposed a multi-task deep learning network for sinus segmentation and CRS recurrence prediction simultaneously to develop and validate a deep learning radiomics-based nomogram for preoperatively predicting recurrence in CRS patients who needed surgical treatment. 265 paranasal sinuses computed tomography (CT) images of CRS from two independent medical centers were analyzed to build and test models. The sinus segmentation model achieved good segmentation results. Furthermore, the nomogram combining a deep learning signature and clinical factors also showed excellent recurrence prediction ability for CRS. Our study not only facilitates a technique for sinus segmentation but also provides a noninvasive method for preoperatively predicting recurrence in patients with CRS.

How to manage recurrences after surgery in CRSwNP patients in the biologic era: a narrative review

Objective

This narrative review analyses factors affecting recurrence of Chronic rhinosinusitis with nasal polyps (CRSwNP) after surgery, such as type, extension and completeness of endoscopic sinus surgery (ESS). We also described new implications in the management of recurrences after the advent of biologics.

Methods

We identified four topics: definition of disease state; factors linked to recurrence of polyps; evaluation and management of recurrence in clinical practice.

Results

We analysed the differences between exacerbation and recurrence, as well as the concept of "controlled disease". We focused on potential predictors of recurrence after ESS, such as type 2 inflammation, asthma, aspirin-exacerbated respiratory disease, incomplete initial surgery and lack of adherence to long-term post-operative local corticosteroids. We discussed the new aspects of diagnosis and treatment of recurrences after surgery, summarising our suggestions in a detailed algorithm for practical management of patients with recurrent disease.

Conclusions

The results emphasised the importance of accurate evaluation of patients with CRSwNP recurrence, focusing on the reasons of failure and risk of disease progression, in order to guide personalised interventions. It is crucial to define the concept of appropriate surgery, which affects the choice between starting a biologic or repeating surgery.

Pathogenesis of Nasal Polyposis: Current Trends

Chronic Rhinosinusitis (CRS) is characterized by edema of the sub-epithelial layers, but, only specific types of CRS are developing polyps. Nasal polyposis may develop under different pathogenetic mechanisms rendering the typical macroscopic classification of CRS, with or without nasal polyps, rather deficient. Currently, we approach nasal polyposis, in terms of diagnosis and treatment, according to its endotype, which means that we focus on the specific cells and cytokines that are participating in its pathogenesis. It appears that the molecular procedures that contribute to polyp formation, initiating with a Th-2 response of the adaptive immune system, are local phenomena occurring in the sub-epithelial layers of the mucosa. Several hypotheses are trying to approach the etiology that drives the immune response towards Th-2 type. Extrinsic factors, like fungi, Staphylococcus superantigens, biofilms, and altered microbiome can contribute to a modified and intense local reaction of the immune system. Some hypotheses based on intrinsic factors like the elimination of Treg lymphocytes, low local vitamin-D levels, high levels of leukotrienes, epithelial to mesenchymal transition (EMT) induced by hypoxia, and altered levels of NO, add pieces to the puzzle of the pathogenesis of nasal polyposis. Currently, the most complete theory is that of epithelial immune barrier dysfunction. Intrinsic and extrinsic conditions can damage the epithelial barrier rendering sub-epithelial layers more vulnerable to invasion by pathogens that trigger a Th-2 response of the adaptive immune system. Th2 cytokines, subsequently, induce the accumulation of eosinophils and IgE together with the remodeling of the stroma in the sub-epithelial layers leading, eventually, to the formation of nasal polyps.