The interleukin-4/interleukin-13 pathway in type 2 inflammation in chronic rhinosinusitis with nasal polyps.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is predominantly a type 2 inflammatory disease associated with type 2 (T2) cell responses and epithelial barrier, mucociliary, and olfactory dysfunction. The inflammatory cytokines interleukin (IL)-4, IL-13, and IL-5 are key mediators driving and perpetuating type 2 inflammation. The inflammatory responses driven by these cytokines include the recruitment and activation of eosinophils, basophils, mast cells, goblet cells, M2 macrophages, and B cells. The activation of these immune cells results in a range of pathologic effects including immunoglobulin E production, an increase in the number of smooth muscle cells within the nasal mucosa and a reduction in their contractility, increased deposition of fibrinogen, mucus hyperproduction, and local edema. The cytokine-driven structural changes include nasal polyp formation and nasal epithelial tissue remodeling, which perpetuate barrier dysfunction. Type 2 inflammation may also alter the availability or function of olfactory sensory neurons contributing to loss of sense of smell. Targeting these key cytokine pathways has emerged as an effective approach for the treatment of type 2 inflammatory airway diseases, and a number of biologic agents are now available or in development for CRSwNP. In this review, we provide an overview of the inflammatory pathways involved in CRSwNP and describe how targeting key drivers of type 2 inflammation is an effective therapeutic option for patients.

Exploring the immunopathology of type 2 inflammatory airway diseases.

Significant advancements have been achieved in understanding the roles of different immune cells, as well as cytokines and chemokines, in the pathogenesis of eosinophilic airway conditions. This review examines the pathogenesis of Chronic Rhinosinusitis with Nasal Polyps (CRSwNP), marked by complex immune dysregulation, with major contributions from type 2 inflammation and dysfunctional airway epithelium. The presence of eosinophils and the role of T-cell subsets, particularly an imbalance between Treg and Th17 cells, are crucial to the disease's pathogenesis. The review also investigates the pathogenesis of eosinophilic asthma, a unique asthma subtype. It is characterized by inflammation and high eosinophil levels, with eosinophils playing a pivotal role in triggering type 2 inflammation. The immune response involves Th2 cells, eosinophils, and IgE, among others, all activated by genetic and environmental factors. The intricate interplay among these elements, chemokines, and innate lymphoid cells results in airway inflammation and hyper-responsiveness, contributing to the pathogenesis of eosinophilic asthma. Another scope of this review is the pathogenesis of Eosinophilic Granulomatosis with Polyangiitis (EGPA); a complex inflammatory disease that commonly affects the respiratory tract and small to medium-sized blood vessels. It is characterized by elevated eosinophil levels in blood and tissues. The pathogenesis involves the activation of adaptive immune responses by antigens leading to T and B cell activation and eosinophil stimulation, which causes tissue and vessel damage. On the other hand, Allergic Bronchopulmonary Aspergillosis (ABPA) is a hypersensitive response that occurs when the airways become colonized by aspergillus fungus, with the pathogenesis involving activation of Th2 immune responses, production of IgE antibodies, and eosinophilic action leading to bronchial inflammation and subsequent lung damage. This analysis scrutinizes how an imbalanced immune system contributes to these eosinophilic diseases. The understanding derived from this assessment can steer researchers toward designing new potential therapeutic targets for efficient control of these disorders.

Butyrate inhibits type 2 inflammation in eosinophilic chronic rhinosinusitis.

Butyrate and other Short-chain fatty acids (SCFAs) are microbial metabolites from Bacteroides and Clostridium species that may suppress type 2 inflammation. However, the mechanisms of SCFAs in the nasal sinuses are not fully understood. We aimed to clarify the in vitro and in vivo roles of SCFAs in eosinophilic chronic rhinosinusitis (ECRS) pathophysiology. We investigated whether SCFAs induced changes in type 2 cytokines, IgE, and apoptosis and the roles of GPR41, GPR43, and histone deacetylase. Analysis of the control subjects demonstrated that butyrate of SCFAs effectively inhibited type 2 cytokine production in PBMCs, ILC2s, and CD4+ T cells and IgE production in CD19+ B cells. In annexin V analysis, butyrate also induced late apoptosis of PBMCs. The butyrate-induced inhibition of type 2 cytokines appeared involved in histone deacetylase inhibition but not in GPR41 or GPR43. In an analysis of ECRS in humans, butyrate inhibited type 2 cytokine production in PBMCs and nasal polyp-derived cells. The butyrate concentration in nasal lavage fluid was significantly decreased in ECRS patients compared to controls and non-ECRS patients. Our findings confirm that butyrate can inhibit type 2 inflammation and may be a potential therapeutic target for ECRS.

Galectin-10 in serum extracellular vesicles reflects asthma pathophysiology.

BACKGROUND: Novel biomarkers (BMs) are urgently needed for bronchial asthma (BA) with various phenotypes and endotypes. OBJECTIVE: We sought to identify novel BMs reflecting tissue pathology from serum extracellular vesicles (EVs). METHODS: We performed data-independent acquisition of serum EVs from 4 healthy controls, 4 noneosinophilic asthma (NEA) patients, and 4 eosinophilic asthma (EA) patients to identify novel BMs for BA. We confirmed EA-specific BMs via data-independent acquisition validation in 61 BA patients and 23 controls. To further validate these findings, we performed data-independent acquisition for 6 patients with chronic rhinosinusitis without nasal polyps and 7 patients with chronic rhinosinusitis with nasal polyps. RESULTS: We identified 3032 proteins, 23 of which exhibited differential expression in EA. Ingenuity pathway analysis revealed that protein signatures from each phenotype reflected disease characteristics. Validation revealed 5 EA-specific BMs, including galectin-10 (Gal10), eosinophil peroxidase, major basic protein, eosinophil-derived neurotoxin, and arachidonate 15-lipoxygenase. The potential of Gal10 in EVs was superior to that of eosinophils in terms of diagnostic capability and detection of airway obstruction. In rhinosinusitis patients, 1752 and 8413 proteins were identified from EVs and tissues, respectively. Among 11 BMs identified in EVs and tissues from patients with chronic rhinosinusitis with nasal polyps, 5 (including Gal10 and eosinophil peroxidase) showed significant correlations between EVs and tissues. Gal10 release from EVs was implicated in eosinophil extracellular trapped cell death in vitro and in vivo. CONCLUSION: Novel BMs such as Gal10 from serum EVs reflect disease pathophysiology in BA and may represent a new target for liquid biopsy approaches.

Reduced Proliferative Capacity and Defense against Staphylococcus aureus in Human Nasal Mucosal Epithelium Lacking ZNF365.

INTRODUCTION: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a common chronic inflammatory disease of the nose characterized by barrier disruption and environmental susceptibility, and the deletion of ZNF365 may be a factor inducing these manifestations. However, there is no study on the mechanism of action between CRSwNP and ZNF365. Therefore, this study focuses on the effect of the zinc finger protein ZNF365 on the proliferation of nasal mucosal epithelial cells and their defense against Staphylococcus aureus (S. aureus). METHODS: Immunohistochemistry and Western blot were applied to verify the changes of ZNF365 expression in nasal polyp tissues and control tissues, as well as in primary epithelial cells. ZNF365 was knocked down in human nasal mucosa epithelial cell line (HNEpc), and the proliferation, migration, and transdifferentiation of epithelium were observed by immunofluorescence, QPCR, CCK8, and cell scratch assay. The changes of mesenchymal markers and TLR4-MAPK-NF-κB pathway were also observed after the addition of S. aureus. RESULTS: ZNF365 expression was reduced in NP tissues and primary nasal mucosal epithelial cells compared to controls. Knockdown of ZNF365 in HNEpc resulted in decreased proliferation and migration ability of epithelial cells and abnormal epithelial differentiation (decreased expression of tight junction proteins). S. aureus stimulation further inhibited epithelial cell proliferation and migration, while elevated markers of epithelial-mesenchymal transition and inflammatory responses occurred. CONCLUSION: ZNF365 is instrumental in maintaining the proliferative capacity of nasal mucosal epithelial cells and defending against the invasion of S. aureus. The findings suggest that ZNF365 may participate in the development of CRSwNP.

Identification of Pyroptosis-Related Genes Regulating the Progression of Chronic Rhinosinusitis with Nasal Polyps.

INTRODUCTION: Chronic rhinosinusitis with nasal polyps (CRSwNP) is an immunologic disease, and pyroptosis, an inflammation-based cellular death, strictly modulates CRSwNP pathology, whereas the pyroptosis genes and mechanisms involved in CRSwNP remain unclear. Herein, we explored disease biomarkers and potential therapeutic targets for pyroptosis and immune regulation in CRSwNP using bioinformatics analysis and tissue-based verification. METHODS: We retrieved the transcriptional profiles of the high-throughput dataset GSE136825 from the Gene Expression Omnibus database, as well as 170 pyroptosis-related gene expressions from GeneCards. Using R, we identified differentially expressed pyroptosis-related genes and examined the potential biological functions of the aforementioned genes using Gene Ontology, Kyoto Encyclopedia of the Genome pathway, immune infiltration, and protein-protein interaction (PPI) network analyses, thereby generating a list of hub genes. The hub genes were, in turn, verified using real-time quantitative polymerase chain reaction (qRT-PCR), immunohistochemistry (IHC), and Western blotting (WB). Ultimately, using the StarBase and miRTarBase databases, we estimated the targeting microRNAs and long chain non-coding RNAs. RESULTS: We demonstrated that the identified pyroptosis-related genes primarily modulated bacterial defense activities, as well as inflammasome immune response and assembly. Moreover, they were intricately linked to neutrophil and macrophage infiltration. Furthermore, we validated the tissue contents of hub genes AIM2, NLPR6, and CASP5 and examined potential associations with clinical variables. We also developed a competitive endogenous RNA (ceRNA) modulatory axis to examine possible underlying molecular mechanisms. CONCLUSION: We found AIM2, CASP5, and NLRP6, three hub genes for pyroptosis in chronic rhinosinusitis with nasal polyps, by biological analysis, experimental validation, and clinical variable validation.

IL-13 and IL-13-induced periostin levels are specifically decreased in patients following endoscopic sinus surgery for chronic rhinosinusitis.

BACKGROUND: Type 2 (T2) inflammation plays a pathogenic role in chronic rhinosinusitis (CRS). The effects of endoscopic sinus surgery (ESS) on T2 inflammation are unknown. OBJECTIVE: The aim of this study was to compare T2 inflammatory biomarkers from middle meatal (MM) mucus for distinguishing patients with CRS from CRS-free patients, identifying major phenotypes (CRS without nasal polyps [CRSsNP] and CRS with nasal polyps [CRSwNP]), assessing endotypic change, and establishing cross-sectional and longitudinal outcomes in patients undergoing ESS. METHODS: MM mucus samples were collected from patients with CRSsNP and patients with CRSwNP before and 6 to 12 months after ESS and compared with samples from CRS-free control patients. T2 biomarkers were evaluated both continuously and using threshold-based definitions of T2 endotype to identify relationships with patient-reported (based on the 22-Item Sinonasal Outcomes Test and Chronic Rhinosinusitis Patient-Reported Outcomes Measure) and clinician-reported (radiographic and endoscopic) severity. Linear mixed models were developed to analyze clinical variables associated with T2 biomarker levels. RESULTS: A total of 154 patients with CRS (89 with CRSsNP and 65 with CRSwNP) were enrolled, with a mean interval of 9 months between ESS and follow-up. An analysis of pre-ESS MM mucus samples revealed elevated levels of T2 mediators in patients with CRSwNP versus in patients with CRSsNP and CRS-free controls. Temporally stable correlations between levels of IL-13 and IL-5, levels of periostin and complement 5a, and levels of eosinophil cationic protein (ECP) and eotaxin-3 were observed. On this basis and on the basis of pathologic significance, levels of IL-13, periostin and ECP were further analyzed. After ESS, levels of IL-13 and periostin decreased significantly, whereas ECP levels remained unchanged. Across pre- and post-ESS evaluation, the T2 endotype was associated with radiographic severity but did not predict outcomes. CRSwNP status and African American race were associated with higher levels of IL-13 and periostin, whereas ECP level was higher in patients undergoing extensive surgery. CONCLUSION: ESS decreased levels of IL-13 and periostin in the middle meatus. T2 inflammation after ESS was correlated with patient- and clinician-reported severity across phenotypes. Pre-ESS T2 inflammation did not predict post-ESS outcomes.

Association of cytokine profile with prior treatment failure and revision surgery in chronic rhinosinusitis.

BACKGROUND: Inflammatory patterns in chronic rhinosinusitis (CRS) may predict disease severity, need for multiple sinus surgeries, and treatment response. This study analyzes nasal mucus inflammatory cytokine patterns in patients with (CRSwNP) and without (CRSsNP) nasal polyposis and their association with revision sinus surgery. METHODS: A total of 319 CRS patients who underwent sinus surgery were included. Cytokines were quantified in intraoperative mucus specimens using a multiplex flow cytometric bead assay. Cytokine expression patterns in patients with 0, 1, and ≥2 previous surgeries were analyzed using Kruskal-Wallis and principal component (PC) regression analyses. RESULTS: There were 122 (38%) patients with CRSsNP and 197 (62%) with CRSwNP. On univariate analysis, interleukin (IL)-1ß, IL-6, IL-8, and IL-21 were associated with increasing number of sinus surgeries in CRSsNP, as were IL-2, IL-4, IL-5, IL-6, IL-9, IL-17A, and tumor necrosis factor (TNF)-α in CRSwNP. PC analysis with continuous Poisson regression in CRSwNP demonstrated that high IL-5 and IL-13 and low IL-1ß, IL-12, and IL-21 were associated with more prior surgeries. In CRSsNP low IL-13 and high IL-5 and regulated-on-activation, normal T-cell-expressed and secreted (RANTES) were associated with more prior surgeries. Age remained a significant covariate in the full regression model for CRSsNP, but was nonsignificant in CRSwNP. CONCLUSION: In CRSwNP, elevated IL-5 and IL-13 levels were higher at time of surgery in patients with more prior surgeries. Type 2 cytokines in CRSsNP demonstrated mixed associations with revision surgery. For both phenotypes, IL-10, IL-12, and IL-21 were consistently lower as number of prior surgeries increased, suggesting that treatment-resistant disease may be modulated by impairment in these signaling pathways.

TIM-4 in macrophages contributes to nasal polyp formation through the TGF-ß1-mediated epithelial to mesenchymal transition in nasal epithelial cells.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is caused by prolonged inflammation of the paranasal sinus mucosa. The epithelial to mesenchymal transition (EMT) is involved in the occurrence and development of CRSwNP. The T-cell immunoglobulin domain and the mucin domain 4 (TIM-4) is closely related to chronic inflammation, but its mechanism in CRSwNP is poorly understood. In our study, we found that TIM-4 was increased in the sinonasal mucosa of CRSwNP patients and, especially, in macrophages. TIM-4 was positively correlated with α-SMA but negatively correlated with E-cadherin in CRS. Moreover, we confirmed that TIM-4 was positively correlated with the clinical parameters of the Lund-Mackay and Lund-Kennedy scores. In the NP mouse model, administration of TIM-4 neutralizing antibody significantly reduced the polypoid lesions and inhibited the EMT process. TIM-4 activation by stimulating with tissue extracts of CRSwNP led to a significant increase of TGF-ß1 expression in macrophages in vitro. Furthermore, coculture of macrophages and human nasal epithelial cells (hNECs) results suggested that the overexpression of TIM-4 in macrophages made a contribution to the EMT process in hNECs. Mechanistically, TIM-4 upregulated TGF-ß1 expression in macrophages via the ROS/p38 MAPK/Egr-1 pathway. In conclusion, TIM-4 contributes to the EMT process and aggravates the development of CRSwNP by facilitating the production of TGF-ß1 in macrophages. Inhibition of TIM-4 expression suppresses nasal polyp formation, which might provide a new therapeutic approach for CRSwNP.

Age related non-type 2 inflammation and its association with treatment outcome in patients with chronic rhinosinusitis with nasal polyp in Korea.

This study aimed to investigate the effect of age in patients with chronic rhinosinusitis with nasal polyp (CRSwNP). 269 patients were divided into eosinophilic and non-eosinophilic groups based on tissue eosinophilia, defined by eosinophils accounting for more than 20% of the total inflammatory cells. Patients were then further divided into younger and older groups based on the age of 35 years. Clinical characteristics including blood eosinophil, Lund Mackay score, and modified Lund-Kennedy (mLK) scores were compared. Levels of 14 cytokines from nasal tissues of an additional 78 patients were analyzed. Tissue eosinophilia was significantly associated with age and the proportion of non-eosinophilic CRSwNP was significantly higher in younger patients as compared to older patients (79.2% vs 56.6%). There was no difference in clinical characteristics and cytokine levels between the younger and older patients with eosinophilic CRSwNP. In contrast, in patients with non-eosinophilic CRSwNP, younger patients had significantly lower preoperative blood eosinophils and higher mLK scores at three and six months, postoperatively, compared to older patients. Alpha-1 antitrypsin and IL-5 levels were significantly lower in younger patients than in older patients in non-eosinophilic CRSwNP. This study suggests a potential association between age, non-type 2 inflammation and treatment outcome in CRSwNP.

Effect of Airborne Particulate Matter on the Immunologic Characteristics of Chronic Rhinosinusitis with Nasal Polyps.

The inflammatory mechanisms of environmental pollutants in chronic rhinosinusitis (CRS) have recently been proposed. However, the mechanisms underlying the inflammatory effects of particulate matter (PM) on nasal polyp (NP) tissues remain unknown. Here we investigated the mechanism underlying the inflammatory effects of PM10 on human nasal polyp-derived fibroblasts (NPDFs). We isolated NPDFs from human NP tissues obtained from patients with CRS with NPs (CRSwNP). The NPDFs were exposed to PM10 in vitro. Immunologic characteristics were assessed using real-time polymerase chain reaction, enzyme-linked immunosorbent assay, Western blot, and flow cytometry. Additionally, we investigated the effect of NPDF-conditioned media (CM) on the expression of CD4+ T cell inflammatory mediators. PM10-treated NPDFs significantly upregulated interleukin (IL)-6, IL-4, and IL-33 expression and CXCL1 protein levels than PM10-treated normal tissues. MAP kinase, AP-1, and NF-kB were the primary cell signaling proteins. Immune cells in NPDF-CM had elevated IL-13, IL-17A, and IL-10 expression, but no significant difference in IFN-γ, TNF-α, and IL-4 expression. Moreover, under a Th2 inducing condition, NPDF-CM-treated CD4+ T cells had increased expression of IL-13, IL-10, and IL-17, which was reversed on ST2 inhibitor addition. Our study suggests that PM10 exposure could significantly increase the Th2 inflammatory pathway in NP tissues, specifically the IL-33/ST2 pathway-mediated immune response.

Extrafollicular PD-1highCXCR5-CD4+ T cells participate in local immunoglobulin production in nasal polyps.

BACKGROUND: Local immunoglobulin hyperproduction is observed in nasal polyps (NPs) with and without ectopic lymphoid tissues (eLTs). OBJECTIVE: Our aim was to identify the T-cell subsets involved in local immunoglobulin production independent of eLTs in NPs. METHODS: The localization, abundance, and phenotype of CD4+ T-cell subsets were studied by immunofluorescence, flow cytometry, and single-cell RNA sequencing. Purified nasal T-cell subsets were cultured with autologous peripheral naive B cells to explore their function. Programmed death ligand 1 and programmed death ligand 2 expression in NPs was investigated by immunofluorescence staining and flow cytometry. RESULTS: Accumulation of PD-1highCXCR5-CD4+ T cells outside lymphoid aggregates was found in NPs. Nasal PD-1highCXCR5-CD4+ T cells were characterized by a unique phenotype that was related to B-cell help and tissue residency and distinct from PD-1-/intCXCR5- and CXCR5+ CD4+ T cells in NPs as well as PD-1highCXCR5highCD4+ follicular helper T cells in tonsils. Compared with the frequencies of PD-1highCXCR5-CD4+ T cells and their IFN-γ+, IL-17A+, and IL-21+ subsets in the control inferior turbinate tissues, the frequencies of these cells and their subsets were increased in both eosinophilic and noneosinophilic NPs, whereas the frequencies of the IL-4+ and IL-4+IL-21+ subsets were increased only in eosinophilic NPs. Nasal PD-1highCXCR5-CD4+ T cells induced immunoglobulin production from B cells in a potency comparable to that induced by tonsillar follicular helper T cells. PD-1highCXCR5-CD4+ T-cell frequencies were correlated with IgE levels in eosinophilic NPs. PD-L1 and PD-L2 suppressed the function of PD-1highCXCR5-CD4+ T cells, and their levels were reduced in NPs. PD-1highCXCR5-CD4+ T-cell abundance was associated with the postsurgical relapse of NPs. CONCLUSION: PD-1highCXCR5-CD4+ T cells participate in local immunoglobulin production independent of eLTs in NPs.

IL-17A-producing sinonasal MAIT cells in patients with chronic rhinosinusitis with nasal polyps.

BACKGROUND: Diverse immune cells contribute to the pathogenesis of chronic rhinosinusitis (CRS), an inflammatory disease of the nasal cavity and paranasal sinuses. However, whether mucosal-associated invariant T (MAIT) cells are present in human sinonasal tissues remains unclear. Furthermore, the characteristics of sinonasal MAIT cells have not been studied in patients with CRS. OBJECTIVE: We investigated the phenotype, function, and clinical implications of MAIT cells in patients with CRS. METHODS: Peripheral blood and sinonasal tissue were obtained from patients with CRS with (CRSwNP) or without nasal polyps (CRSsNP) and healthy controls. MAIT cells were analyzed by flow cytometry. RESULTS: We found that MAIT cells are present in human sinonasal tissues from healthy controls and patients with CRS. The sinonasal MAIT cell population, but not peripheral blood MAIT cells, from patients with CRSsNP, noneosinophilic CRSwNP (NE-NP), or eosinophilic CRSwNP (E-NP) had a significantly higher frequency of activated cells marked by CD38 expression. In functional analysis, the sinonasal MAIT cell population from NE-NP and E-NP had a significantly higher frequency of IL-17A+ cells but lower frequency of IFN-γ+ or TNF+ cells than control sinonasal tissues. Furthermore, CD38 expression and IL-17A production by sinonasal MAIT cells significantly correlated with disease extent evaluated by the Lund-Mackay computed tomography score in patients with E-NP. CONCLUSIONS: Sinonasal MAIT cells exhibit an activated phenotype and produce higher levels of IL-17A in patients with CRSwNP. These alterations are associated with the extent of disease in patients with E-NP.

The role of serum macrophage migration inhibitory factor in preoperative prediction of chronic rhinosinusitis with nasal polyps endotypes.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a highly heterogeneous disease and can be categorized into eosinophilic CRSwNP (eCRSwNP) and non-eosinophilic CRSwNP (neCRSwNP). Exploring effective biomarkers to distinguish endotypes is important for personalized therapies. The present study aims to evaluate the predictive value of serum MIF in CRSwNP endotypes. METHODS: One hundred and twenty CRSwNP patients, including 51 eCRSwNP and 69 neCRSwNP, 40 chronic rhinosinusitis without nasal polyps (CRSsNP) patients and 40 healthy controls (HC) were enrolled. Serum MIF levels were determined by enzyme-linked immunosorbent assay (ELISA). The patients' clinical variables were analyzed for correlations with serum MIF. Receiver operating characteristic (ROC) curve and multivariate analysis were utilized to assess the predictive value of serum MIF in CRSwNP endotypes. RESULTS: The serum MIF levels were significantly higher in CRSwNP group than CRSsNP group and HC group (P < 0.001), and the serum MIF levels were increased in eCRSwNP compared to neCRSwNP group (P = 0.006). Elevated serum MIF levels were significantly correlated with blood eosinophil (B-EOS) count (r = 0.411, P < 0.001), B-EOS percentage (r = 0.377, P < 0.001), visual analog scale score (r = 0.204, P = 0.025), tissue eosinophil (T-EOS) count (r = 0.705, P < 0.001) and T-EOS percentage (r = 0.671, P < 0.001) in CRSwNP patients. ROC curve demonstrated that serum MIF exhibited good preoperative prediction in CRSwNP endotypes (area under the curve = 0.925, P < 0.001). Multivariate regression analysis showed that serum MIF was an independent factor associated with CRSwNP endotypes. CONCLUSIONS: This was the first study identifying serum MIF as a possible specific biomarker for preoperatively distinguishing CRSwNP endotypes. Furthermore, the serum MIF levels were found to be closely associated with the degree of mucosal eosinophil infiltration.

Transcriptome Analysis Identifies Doublesex and Mab-3 Related Transcription Factor (DMRT3) in Nasal Polyp Epithelial Cells of Patients Suffering from Non-Steroidal Anti-Inflammatory Drug-Exacerbated Respiratory Disease (AERD).

BACKGROUND: Aspirin-exacerbated respiratory disease (AERD) is a syndrome characterised by chronic rhinosinusitis, nasal polyps, asthma and aspirin intolerance. An imbalance of eicosanoid metabolism with anover-production of cysteinyl leukotrienes (CysLTs) has been associated with AERD. However, the precise mechanisms underlying AERD are unknown. OBJECTIVE: To establish the transcriptome of the nasal polyp airway epithelial cells derived from AERD patients to discover gene expression patterns in this disease. METHODS: Nasal airway epithelial cells were isolated from 12 AERD polyps and 8 AERD non-polyp nasal mucosa samples as controls from the same subjects. Utilising the Illumina HiSeq 2500 platform, RNA samples were sequenced. Potential gene candidate DMRT3 was selected from the differentially-expressed genes for validation. RESULTS: Comparative transcriptome profiling of nasal epithelial cells was accomplished in AERD. A total of 20 genes had twofold mean regulation expression differences or greater. In addition, 8 genes were upregulated, including doublesex and mab-3 related transcription factor 3 (DMRT3), and 12 genes were downregulated. Differentially regulated genes comprised roles in inflammation, defence and immunity. Metabolic process and embryonic development pathways were significantly enriched. Enzyme-linked immune sorbent assay (ELISA) results of DMRT3 in AERD patients were significantly upregulated compared to controls (p = 0.03). Immunohistochemistry (IHC) of AERD nasal polyps localised DMRT3 and was predominantly released in the airway epithelia. CONCLUSION: Findings suggest that DMRT3 could be potentially involved in nasal polyp development in AERD patients. Furthermore, several genes are downregulated, hinting at the dedifferentiation phenomenon in AERD polyps. However, further studies are imperative to confirm the exact mechanism of polyp formation in AERD patients.

Single-cell analysis pinpoints distinct populations of cytotoxic CD4+ T cells and an IL-10+CD109+ TH2 cell population in nasal polyps.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by a chronic inflammatory process often associated with comorbid asthma. In this study, we analyzed the transcriptomes of single T helper (TH) cells from nasal polyps of patients with CRSwNP and validated these findings using multiparameter flow cytometry. Polyp tissue contained suppressive T regulatory (Treg) cells, TH2 cells, type 2 innate lymphoid cells, and three transcriptionally distinct subsets of cytotoxic CD4+ T cells (CD4+ CTL). GATA3 expression was a feature of polyp Treg cells, whereas TH2 cells highly expressed TCN1, CD200R, and HPGDS and were enriched for genes involved in lipid metabolism. Only a portion of polyp TH2 cells expressed the prostaglandin D2 receptor CRTH2, whereas a subpopulation of CD109+CRTH2- TH2 cells expressed mRNA for common inhibitor receptors including LAG3 and TIM3 and produced IL-10. Together, we resolved the complexity of TH cells in patients with CRSwNP, identifying several distinct clusters of CD4+ CTL and a population of CD109+CRTH2- TH2 cells with putative regulatory potential.

Th17/1-Biased Inflammatory Environment Involved in the Response of Epithelial Cells to Antigen Stimuli in Nasal Polyps.

Several studies showed that IL-17A was significantly increased in nasal polyps (NPs). However, the source and characteristics of IL-17A-producing cells in NPs were not fully understood. We isolated mononuclear cells from NPs and uncinate tissues and analyzed them using flow cytometry. The results indicated that IL-17A was increased in NP tissues compared to uncinate tissues. The main IL-17A-expressing cells were CD3+ T cells in NP tissues, including Th17 cells, Tc17 cells, and γδT17 cells. Not similar to those in uncinate tissues, the majority of Th17 cells highly coexpressed IFN-γ in NP tissues, such as Th17/1 cells, which highly expressed CXCR3, CCR6, RORγt, and T-bet. Furthermore, Th17/1-biased environment increased the response of nasal epithelial cells to bacterial and viral stimuli, implying that Th17/1 cells play a greater role in the pathological development of NPs than Th17 or Th1 cells.

Aspirin Actions in Treatment of NSAID-Exacerbated Respiratory Disease.

Non-steroidal Anti-inflammatory drugs (NSAID)-exacerbated respiratory disease (N-ERD) is characterized by nasal polyposis, chronic rhinosinusitis, adult-onset asthma and hypersensitive reactions to cyclooxygenase-1 (COX-1) inhibitors. Among the available treatments for this disease, a combination of endoscopic sinus surgery followed by aspirin desensitization and aspirin maintenance therapy has been an effective approach. Studies have shown that long-term aspirin maintenance therapy can reduce the rate of nasal polyp recurrence in patients with N-ERD. However, the exact mechanism by which aspirin can both trigger and suppress airway disease in N-ERD remains poorly understood. In this review, we summarize current knowledge of aspirin effects in N-ERD, cardiovascular disease, and cancer, and consider potential mechanistic pathways accounting for the effects of aspirin in N-ERD.