Chronic rhinosinusitis pathogenesis

Immunological Aspects of Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is related to persistent inflammation with a dysfunctional relationship between environmental agents and the host immune system. Disturbances in the functioning of the sinus mucosa lead to common clinical symptoms. The major processes involved in the pathogenesis of CRS include airway epithelial dysfunctions that are influenced by external and host-derived factors which activate multiple immunological mechanisms. The molecular bases for CRS remain unclear, although some factors commonly correspond to the disease: bacterial, fungal and viral infections, comorbidity diseases, genetic dysfunctions, and immunodeficiency. Additionally, air pollution leads increased severity of symptoms. CRS is a heterogeneous group of sinus diseases with different clinical courses and response to treatment. Immunological pathways vary depending on the endotype or genotype of the patient. The recent knowledge expansion into mechanisms underlying the pathogenesis of CRS is leading to a steadily increasing significance of precision medicine in the treatment of CRS. The purpose of this review is to summarize the current state of knowledge regarding the immunological aspects of CRS, which are essential for ensuring more effective treatment strategies.

Relationship between Chronic Rhinosinusitis and the Incidence of Head and Neck Cancer: A National Population-Based Study

We analyzed the relationship between chronic rhinosinusitis (CRS) and the incidence of head and neck cancers (HNCs) in a Korean adult population. This retrospective cohort study included data from the Korean National Health Insurance Service database. Adjustments were made to minimize risk variables for sex, age, diabetes, hypertension, dyslipidemia, and rhinitis between the two groups. The primary endpoint was newly diagnosed HNC between January 2009 and December 2018. Among 1,337,120 subjects in the Korean National Health Insurance Service database, data from 324,774 diagnosed with CRS (CRS group) and 649,548 control subjects (control group) were selected. Patients with CRS exhibited a statistically significant greater risk for nasal cavity/paranasal sinus cancer, hypopharynx/larynx cancer, and thyroid cancer compared with the control group. In the CRS group, the adjusted hazard ratios for nasal cavity/paranasal sinus cancer were 1.809 (95% confidence interval (CI) 1.085–3.016), 1.343 (95% CI 1.031–1.748) for hypopharynx and larynx cancer, and 1.116 (95% CI 1.063–1.173) for thyroid cancer. CRS was associated with a higher incidence of HNCs. Therefore, physicians should carefully consider the possibility of HNC progression and implement therapeutic strategies to minimize the impact of these diseases.

Acupuncture for the Treatment of Chronic Rhinosinusitis: A PRISMA-Compliant Systematic Review and Meta-Analysis

Background. Chronic rhinosinusitis (CRS) is a highly prevalent disease associated with poor quality of life. In this paper, we appraised the role of acupuncture in the treatment of CRS. Methods. Electronic databases were searched for randomized controlled clinical trials (RCTs) that examined the role of acupuncture in CRS. The primary outcome measures included posttreatment CRS severity, as measured by the Visual Analogue Scale (VAS) and Total Effective Rate (TER). The risk of bias and quality of evidence were evaluated according to the Cochrane Collaboration’s risk-of-bias tool and GRADE tool, respectively. Results. Evidence from the RCTs (n = 10) suggested that acupuncture as a monotherapy or adjunctive therapy to conventional treatment was associated with significant improvements in VAS, TER, and quality of life when compared with conventional treatments for CRS. However, there was a similar incidence of adverse events. The risk of bias was unclear and the quality of evidence for each finding was generally moderate to low. Conclusions. Acupuncture as a stand-alone or adjunctive treatment for CRS was associated with clinical symptom improvement and better quality of life, without any risk for serious adverse events. However, the high clinical heterogeneity of the included RCTs and overall moderate-to-low quality of evidence necessitates rigorous, well-designed trials to confirm these findings. Trial Registrations. This trial is registered with PROSPERO (no. CRD42021292135).

Changes of the airway reactivity in patients with rhinosinusitis

Rhinosinusitis is one of the most common conditions in primary and secondary care all over the world. Rhinosinusitis together with asthma and gastroesophageal reflux disease represent the most common causes of chronic cough. The relationship between rhinosinusitis and cough is still not completely understood, however, direct stimulation of nasal mucosa, upper airway cough syndrome, inflammation of the airways, and cough reflex sensitisation play the crucial role in the pathogenesis of chronic cough.

Fibroepithelial Polyps Originating from the Posterior Nasal Septum: A Case Report

Fibroepithelial polyps are benign tumors of mesodermal origin. They rarely occur in the nasal cavity, with only four such cases reported in the relevant English literature. The location was the inferior turbinate in three cases and anterior nasal septum in one case. The etiology has been suggested in other organs; however, it is entirely unknown in the nasal cavity. Pathological findings play an essential role in the diagnosis of fibroepithelial polyps. We report the case of a 76-year-old woman with fibroepithelial polyps originating from the posterior part of the nasal septum. The fibroepithelial polyps were white-yellow lobular masses that differed from a common inflammatory polyp. We made the diagnosis by excluding the other possible tumors based on a pathological examination. This is the first report about fibroepithelial polyps arising from the posterior nasal septum. She had no potential risk factors that might trigger fibroepithelial polyps in the nasal cavity. This case is a valuable example when considering the potential causes (e.g., female hormones and mechanical pressure) of nasal fibroepithelial polyps.

Role of C3a as a Novel Regulator of 25(OH)D3 to 1α,25-Dihydroxyvitamin D3 Metabolism in Upper Airway Epithelial Cells

In patients with chronic rhinosinusitis with nasal polyps, primary human sinonasal epithelial cell (HSNEC) 1α-hydroxylase levels are reduced, as is their ability to metabolize 25-hydroxycholecalciferol [25(OH)D3] to its active metabolite, 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3]. In this study, we sought to identify the factor responsible for the regulation of HSNEC metabolism of 25(OH)D3, focusing on C3 and C3a. Multiple inhaled irritants trigger the release of complement components, C3 and C3a, leading to suppression of 1α-hydroxylase levels in HSNECs. Recombinant C3a was able to decrease 1α-hydroxylase and impair 25(OH)D3 to 1,25(OH)2D3 metabolism, while addition of a C3a receptor antagonist restored conversion. Conversely, 1,25(OH)2D3 suppressed Aspergillus fumigatus-induced C3 and C3a levels in HSNEC supernatant. Given the ability of 1,25(OH)2D3 to modulate LL37 in other cell types, we examined its regulation in HSNECs and relationship to C3a. 1,25(OH)2D3 stimulated the secretion of LL37, whereas A. fumigatus and C3a suppressed it. Conversely, LL37 reduced the release of C3/C3a by HSNECs. Lastly, oral steroid use and in vitro dexamethasone application both failed to increase 1α-hydroxylase or reduce C3a levels. In summary, in this article, we describe for the first time a novel relationship between complement activation and local vitamin D metabolism in airway epithelial cells. The presence of elevated C3/C3a in patients with asthma and/or chronic rhinosinusitis with nasal polyps may account for their impaired HSNEC 25(OH)D3 to 1,25(OH)2D3 metabolism and explain why they receive limited therapeutic benefit from oral vitamin D3 supplementation.

Serum IL-5, POSTN and IL-33 levels in chronic rhinosinusitis with nasal polyposis correlate with clinical severity

BACKGROUND

Chronic rhinosinusitis (CRS) is a group of heterogeneous diseases characterized by epithelial inflammation and tissue eosinophilic infiltration. IL-5, POSTN, and IL-33 are important factors that act as chemoattractants for eosinophils, and a tissue-remodeling protein positively correlated with eosinophils in blood and mediators of eosinophilic infiltration. The aim of the study was to determine the expression of IL-5, POSTN and IL-33, at the gene and protein levels, in eosinophilic CRS with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP), and to correlate this expression with clinical severity.

MATERIALS AND METHODS

The study included 40 CRSwNP patients and 53 CRSsNP patients and 40 control subjects. The expression of IL-5, POSTN and IL-33 mRNA was determined in sinonasal mucosal samples and in nasal polyp tissue by real-time PCR. Protein levels in the serum of CRSwNP patients were measured by ELISA. Computed tomography was evaluated according to Lund-Mackay scores, and visual analog scale scores were assessed.

RESULTS

NP tissue demonstrated significantly higher IL-5 and POSTN mRNA expression than the sinonasal tissue in the CRSsNP and CRSwNP groups. CRS groups demonstrated elevated IL-33 mRNA expression in comparison to controls irrespective of the presence of NP. No correlation was found between IL-5, POSTN and IL-33 mRNA expression and disease severity. CRSwNP group demonstrated significantly higher serum IL-5, POSTN and IL-33 protein levels than controls, and this corresponds to disease severity.

CONCLUSION

Serum IL-5, POSTN and IL-33 levels may be important markers for classification of eosinophilic CRSwNP patients, along with disease severity.

Chronic Rhinosinusitis, S. aureus Biofilm and Secreted Products, Inflammatory Responses, and Disease Severity

Chronic rhinosinusitis (CRS) is a persistent inflammation of the nasal cavity and paranasal sinuses associated with tissue remodelling, dysfunction of the sinuses' natural defence mechanisms, and induction of different inflammatory clusters. The etiopathogenesis of CRS remains elusive, and both environmental factors, such as bacterial biofilms and the host's general condition, are thought to play a role. Bacterial biofilms have significant clinical relevance due to their potential to cause resistance to antimicrobial therapy and host defenses. Despite substantial medical advances, some CRS patients suffer from recalcitrant disease that is unresponsive to medical and surgical treatments. Those patients often have nasal polyps with tissue eosinophilia, S. aureus-dominant mucosal biofilm, comorbid asthma, and a severely compromised quality of life. This review aims to summarise the contemporary knowledge of inflammatory cells/pathways in CRS, the role of bacterial biofilm, and their impact on the severity of the disease. Here, an emphasis is placed on S. aureus biofilm and its secreted products. A better understanding of these factors might offer important diagnostic and therapeutic perceptions for recalcitrant disease.

A review of phase III clinical trials of US FDA-approved biologic therapies for chronic rhinosinusitis with nasal polyposis

Chronic rhinosinusitis with nasal polyposis is a heterogenous disease with complex underlying pathophysiologic mechanisms. Biologics have been proven to be an effective add-on therapeutic option in severe and/or refractory cases. Currently, dupilumab, omalizumab and mepolizumab have phase III data to support their use in these patients and have received approval from the United States Food and Drug Administration specifically for the treatment of nasal polyposis. Each of these biologics has shown its ability to reduce nasal polyp size and improve nasal congestion/obstruction and sense of smell, but additional research is needed to directly compare the efficacy and safety of the different biologic agents for different nasal polyposis endotypes.

Differential expression profile of plasma exosomal microRNAs in chronic rhinosinusitis with nasal polyps

Exosomes mediate inflammation and immune responses. The aim of the study was to examine the expression profiles of plasma exosomal microRNAs (miRNAs) and analyze their target gene functions in participants with chronic rhinosinusitis with nasal polyps (CRSwNP). We measured plasma exosomal miRNAs in five patients with CRSwNP and five controls. Transcripts per million (TPM) was used to assess miRNAs expression and the Benjamini-Hochberg procedure was employed for multiple comparisons correction. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene ontology (GO) analyses revealed biological annotation and functional prediction of target genes. Compared with controls, we found that 159 exosomal miRNAs were differentially expressed by miRNA sequencing in CRSwNP. The top three upregulated miRNAs were novel_miR_677, novel_miR_1037, and novel_miR_79, while the top three downregulated miRNAs were novel_miR_192, novel_miR_1022, and novel_miR_4. The target functions in the GO and KEGG analyses included axon guidance, extracellular matrix (ECM)-receptor interaction, protein digestion and absorption, the calcium, the Hippo, the Notch, the ErbB, the cAMP signaling pathway, and focal adhesion. This study describes the dissection of plasma exosomal miRNA profiling in CRSwNP. Our findings may provide a certain basis for further mechanism research and exploration of diagnostic values.

Nasal Mucociliary Clearance and Sinonasal Symptoms in Healthcare Professionals Wearing FFP3 Respirators: A Prospective Cross-Sectional Study

Introduction

The purpose of the present study was to assess nasal mucociliary clearance (NMC) and sinonasal symptoms of healthcare professionals wearing filtering facepiece-3 (FFP3) respirators.

Methods

This prospective cross-sectional study was conducted at a large tertiary care academic center. Thirty-four healthcare professionals working at a coronavirus disease-19 patient care unit were included in the study. Visual analog scale (VAS) scores of sinonasal symptoms (nasal discharge, postnasal discharge, nasal blockage, hyposmia, facial pain/pressure, facial fullness, headache, fatigue, halitosis, cough) and the NMC times of the participants were assessed immediately before wearing FFP3 respirators and after 4 h of work with FFP3 respirators.

Results

The mean age of the participants was 28.82 ± 4.95 (range, 26–31) years. Twenty participants were female and 14 were male. After wearing the FFP3 respirators for 4 h, a statistically significant increase was observed in total VAS scores for all sinonasal symptoms and NMC times (p < 0.001). When the VAS score of each sinonasal symptom was evaluated separately, a statistically significant increase was found for VAS scores of nasal discharge, postnasal discharge, nasal blockage, hyposmia, facial pain/pressure, and facial fullness (p < 0.05).

Conclusion

The present study shows that nasal mucosal functions might be affected significantly after 4 h of using FFP3 respirators. The long-term effects and clinical significance of these short-term changes should be investigated on healthcare professionals in further studies.

The effect of Ramadan fasting on nasal mucociliary activity and peak nasal inspiratory flow

PURPOSE

In this study, we aimed to investigate the effect of Ramadan fasting (RF) on nasal mucociliary clearance (MCC) and peak nasal inspiratory flow (PNIF).

METHODS

Sixty-two (41 male and 21 female) healthy subjects who stated that they would fast continuously during the month of Ramadan were included in this prospective study. Day 0 (baseline), 1st day (after one day of RF), and 29th (after 29 days of RF) nasal mucociliary clearance time (MCT) with saccharine test and PNIF values were determined. Subject weights (SW) were measured on Day 0 and Day 29. The obtained data were analyzed statistically.

RESULTS

The mean of SW on day 0 was 78.53 ± 10.95 kg, and the mean of SW on Day 29 was 78.69 ± 10.87 kg. There was no significant difference in terms of SW (p = 0.251, p > 0.05). A significant difference was found between the MCT and PNIF values measured on different study days (p < 0.05). The MCT values for Day 29 were significantly higher than the values for other days (p < 0.05). There was no significant difference between the MCT values on the first day and the baseline (p = 0.891, p > 0.05). The PNIF values for Day 29 were significantly higher than the values for other days (p < 0.05). The PNIF values on the first day were significantly higher than the baseline (p = 0.008, p < 0.05).

CONCLUSION

The present study showed that RF leads to MCT prolongation and PNIF increase. Ramadan fasting causes deterioration in nasal airway defense and improvement in nasal respiration.

Mechanisms and pathogenesis of chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is a heterogeneous disease characterized by local inflammation of the upper airways and is historically divided into 2 main phenotypes: CRS with nasal polyps and CRS without nasal polyps. Inflammation in CRS is mainly characterized by 3 endotypes based on elevation of canonical lymphocyte cytokines: type (T) 1 (T1) by TH1 cytokine IFN-γ, T2 by TH2 cutokines IL-4, IL-5, and IL-13, and T3 by TH17 cytokines including IL-17. Inflammation in both CRS without nasal polyps and CRS with nasal polyps is highly heterogeneous, and the frequency of various endotypes varies geographically around the world. This finding complicates establishment of a unified understanding of the mechanisms of pathogenesis in CRS. Sinonasal epithelium acts as a passive barrier, and epithelial barrier dysfunction is a common feature in CRS induced by endotype-specific cytokines directly and indirectly. The sinonasal epithelium also participates in both innate immunity via recognition by innate pattern-recognition receptors and promotes and regulates adaptive immunity via release of chemokines and innate cytokines including thymic stromal lymphopoietin. The purpose of this review was to discuss the contribution of the epithelium to CRS pathogenesis and to update the field regarding endotypic heterogeneity and various mechanisms for understanding pathogenesis in CRS.

TLR Signals in Epithelial Cells in the Nasal Cavity and Paranasal Sinuses

The respiratory tract is constantly at risk of invasion by microorganisms such as bacteria, viruses, and fungi. In particular, the mucosal epithelium of the nasal cavity and paranasal sinuses is at the very forefront of the battles between the host and the invading pathogens. Recent studies have revealed that the epithelium not only constitutes a physical barrier but also takes an essential role in the activation of the immune system. One of the mechanisms equipped in the epithelium to fight against microorganisms is the Toll-like receptor (TLR) response. TLRs recognize common structural components of microorganisms and activate the innate immune system, resulting in the production of a plethora of cytokines and chemokines in the response against microbes. As the epithelia-derived cytokines are deeply involved in the pathogenesis of inflammatory conditions in the nasal cavity and paranasal sinuses, such as chronic rhinosinusitis (CRS) and allergic rhinitis (AR), the molecules involved in the TLR response may be utilized as therapeutic targets for these diseases. There are several differences in the TLR response between nasal and bronchial epithelial cells, and knowledge of the TLR signals in the upper airway is sparse compared to that in the lower airway. In this review, we provide recent evidence on TLR signaling in the upper airway, focusing on the expression, regulation, and responsiveness of TLRs in human nasal epithelial cells (HNECs). We also discuss how TLRs in the epithelium are involved in the pathogenesis of, and possible therapeutic targeting, for CRS and AR.

Olfactory Change Pattern After Endoscopic Sinus Surgery in Chronic Rhinosinusitis Patients

Background Chronic rhinosinusitis (CRS) is a chronic inflammation of the sinonasal mucosa that is clinically associated with sinus pressure, nasal congestion, rhinorrhea, and a decreased sense of smell that lasts more than 12 weeks. Endoscopic sinus surgery (ESS) for medically refractory CRS is mainly undergone to improve sinus function and access to topical medicinal treatments. However, olfactory changes after ESS can be unpredictable. Aim The current study aimed to assess olfactory change patterns after endoscopic sinus surgery in patients with chronic rhinosinusitis. Methods A record-based retrospective study was conducted in Aseer Central Hospital (ACH) ear, nose, and throat outpatient (ENT OPD) department and Khamis Mushayt General Hospital from August 15, 2021, to December 15, 2021. Data were collected using pre-structured data extraction sheet to avoid errors. Data extracted and collected included patients' biodemographic data, CRS-associated symptoms, and endoscopic surgery-related data, including duration since surgery, presurgical medications, and duration of surgery. Also, postsurgical complications were extracted, especially olfactory complications. Results A total of 168 patients with chronic rhinosinusitis (CRS) and who had undergone endoscopic sinus surgery in the Aseer region were included. Patient ages ranged from 10 to 61 years, with a mean age of 39.8 ± 12.4 years old. Regarding the associated symptoms and complaints of the study patients, 110 (65.5%) complained of sinusitis, and 86 (51.2%) had allergic RS. The postsurgical complications of patients with CRS who had undergone endoscopic sinus surgery were olfactory dysfunction (OD) in 32 (19%), no complications in 115 (68.55%), and other nonspecific complications, such as headache, drowsiness, nose dryness, and bleeding, in 21 (12.55%). Also, 71 (42.3%) reported that they hardly perceive the fragrance in perfumeries. Conclusion In conclusion, olfactory impairment is a frequent clinical presentation in patients with CRS. In this study, olfactory dysfunction was improved, except among nearly one out of each five patients after ESS. Olfactory dysfunction was more among patients who had undergone recent surgery and those with chronic rhinosinusitis with nasal polyps (CRSwNP). Also, among patients who reported no complications, olfactory function did not return to normal in most patients as they hardly perceive fragrance.

Endotypes of chronic rhinosinusitis: Relationships to disease phenotypes, pathogenesis, clinical findings, and treatment approaches

Chronic rhinosinusitis (CRS) is a common clinical syndrome that produces significant morbidity and costs to our health system. The study of CRS has progressed from an era focused on phenotype to include endotype-based information. Phenotypic classification has identified clinical heterogeneity in CRS based on endoscopically observed features such as presence of nasal polyps, presence of comorbid or systemic diseases, and timing of disease onset. More recently, laboratory-based findings have established CRS endotype based upon specific mechanisms or molecular biomarkers. Understanding the basis of widespread heterogeneity in the manifestations of CRS is advanced by findings that the three main endotypes, Type 1, 2, and 3, orchestrate the expression of three distinct large sets of genes. The development and use of improved methods of endotyping disease in the clinic are ushering in an expansion of the use of biological therapies targeting Type 2 inflammation now and perhaps other inflammatory endotypes in the near future. The purpose of this review is to discuss the phenotypic and endotypic heterogeneity of CRS from the perspective of advancing the understanding of the pathogenesis and improvement of treatment approaches and outcomes.

Age-Associated Changes of Nasal Bacterial Microbiome in Patients With Chronic Rhinosinusitis

Age-related changes in nasal bacterial microbiota of patients with chronic rhinosinusitis (CRS) remains unclear. In this study, we aimed to identify distinct characteristics of nasal bacterial microbiota between aged and younger patients with CRS through 16S rDNA gene sequencing. Patients with CRS undergoing endoscopic sinus surgery were recruited and separated into aged (≥60 years, median age = 66 years, N = 17) and younger (<60 years, median age = 35.5 years, N = 14) patients. Diversity, bacterial composition and metabolic activities of nasal microbiota between aged and younger patients were compared. Results have shown that levels of OTUs (p = 0.0173) and microbiota diversity (all p < 0.05) decreased significantly in aged patients. The abundance of phylum Actinobacteria, and genus Corynebacterium were significantly higher in aged patients, while the abundance of phylum Bacteroidetes, Fusobacteria, and genus Fusobacterium, Peptoniphilus were significantly higher in younger patients. In addition, predicted functional profiles have revealed that 41 KEGG pathways involving in 12 metabolic pathways, 4 genetic information processing, 3 environmental information processing, 4 cellular processes, 8 organismal systems, 6 human diseases, and 4 unclassified pathways were identified. Among which, the vast majority of metabolic activities are involved in replication and repair, membrane transport, translation, and the metabolism of amino acid, carbohydrate, energy, cofactors and vitamins, and nucleotide. On the level of the thirdly bacterial metabolic pathways, purine metabolism, glycine, serine and threonine metabolism, valine, leucine and isoleucine biosynthesis, glycolysis/gluconeogenesis and phenylalanine, tyrosine and tryptophan biosynthesis are significantly up-regulated while carbon fixation pathways in prokaryotesand methane metabolism are significantly down-regulated in aged patients. Overall, our analysis revealed that age-related physiological and pathological changes on the nasal mucosal surface may alter the host immune response and be highly associated with the nasal bacterial microbiota of patients with CRS. However, future studies are needed to elucidate the causal relationship.

Expert Opinion on Biological Treatment of Chronic Rhinosinusitis with Nasal Polyps in the Gulf Region

Chronic rhinosinusitis (CRS) is defined as the inflammation of nose and paranasal sinuses, affecting the patients' quality of life and productivity. Chronic rhinosinusitis with nasal polyps (CRSwNP) is a principal clinical entity confirmed by the existence of chronic sinonasal inflammation and is characterized by anterior or posterior rhinorrhea, nasal congestion, hyposmia and/or facial pressure or facial pain. Several epidemiologic studies have revealed wide variations in the incidence of CRS among regions globally ranging from 4.6% to 12%. The Gulf countries are also witnessing an unprecedented burden of CRSwNP. According to the current clinical guidelines, glucocorticosteroids and antibiotics are the principal pharmacotherapeutic approaches. Endoscopic sinus surgery is recommended for those who have failed maximal pharmacotherapy. Recently, biologics are considered as an alternative best approach due to the complications associated with medical therapy and surgery. However, precise data on the clinical position of biologic agents in the management of CRSwNP in the Gulf region is not available. The present review article addresses the current diagnostic and management approaches for CRSwNP and also emphasizes the role of emerging biologics in the current treatment strategies for CRSwNP in the Gulf region. Further, a consensus protocol was convened to rationalize the guideline recommendations, strategize the best practices with biologics, and develop clinical practice guidelines for all primary-care specialists in the Gulf region. The consensus-based report will be a useful reference tool for primary-care physicians in primary-healthcare settings, regarding the appropriate time for the initiation of biological treatment in the Gulf region.

The bitter end: T2R bitter receptor agonists elevate nuclear calcium and induce apoptosis in non-ciliated airway epithelial cells

Bitter taste receptors (T2Rs) localize to airway motile cilia and initiate innate immune responses in retaliation to bacterial quorum sensing molecules. Activation of cilia T2Rs leads to calcium-driven NO production that increases cilia beating and directly kills bacteria. Several diseases, including chronic rhinosinusitis, COPD, and cystic fibrosis, are characterized by loss of motile cilia and/or squamous metaplasia. To understand T2R function within the altered landscape of airway disease, we studied T2Rs in non-ciliated airway cell lines and primary cells. Several T2Rs localize to the nucleus in de-differentiated cells that typically localize to cilia in differentiated cells. As cilia and nuclear import utilize shared proteins, some T2Rs may target to the nucleus in the absence of motile cilia. T2R agonists selectively elevated nuclear and mitochondrial calcium through a G-protein-coupled receptor phospholipase C mechanism. Additionally, T2R agonists decreased nuclear cAMP, increased nitric oxide, and increased cGMP, consistent with T2R signaling. Furthermore, exposure to T2R agonists led to nuclear calcium-induced mitochondrial depolarization and caspase activation. T2R agonists induced apoptosis in primary bronchial and nasal cells differentiated at air-liquid interface but then induced to a squamous phenotype by apical submersion. Air-exposed well-differentiated cells did not die. This may be a last-resort defense against bacterial infection. However, it may also increase susceptibility of de-differentiated or remodeled epithelia to damage by bacterial metabolites. Moreover, the T2R-activated apoptosis pathway occurs in airway cancer cells. T2Rs may thus contribute to microbiome-tumor cell crosstalk in airway cancers. Targeting T2Rs may be useful for activating cancer cell apoptosis while sparing surrounding tissue.

Novel involvement of PLD-PKCδ-CREB axis in regulating FGF-2-mediated pentraxin 3 production in human nasal fibroblast cells

A higher expression level of mitogenic fibroblast growth factor-2 (FGF-2) has been reported in human nasal mucus of both chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). Meanwhile, we have shown that long pentraxin 3 (PTX3), an essential component of humoral innate immunity that is produced at sites of infection and inflammation, was overproduced in human nasal mucosae and secretions of CRSsNP. Therefore, this study was aimed to investigate how FGF-2 regulates PTX3 expression in human CRSsNP nasal mucosa-derived fibroblast cells (hNMDFs). The FGF-2 treatment caused ptx3 mRNA expression and PTX3 protein induction and secretion. In parallel, a differential expression of FGF receptor (FGFR)-1 to FGFR-4 was observed in hNMDFs and human nasal tissues. While conventionally known PI3K/Akt/mTOR and AP-1 pathways following FGFR activation were shown to be involved, the protein kinase Cδ (PKCδ) and cAMP response element-binding protein (CREB) were also found to be as critical signaling molecules in FGF-2-induced PTX3 induction. The PKCδ and CREB activation could be detected in total cells and in the cell nucleus. Accordingly, a novel CREB binding sequence was detected in the human ptx3 promoter region and could interact with activated CREB in cells challenged with FGF-2. Surprisingly, the phospholipase D (PLD), but not phosphoinositide- and phosphatidylcholine-phospholipase C, was necessarily required for PKCδ and CREB activation. Therefore, we demonstrated here for the first time that FGF-2 mediates PTX3 production not only through PI-3K/Akt/mTOR and AP-1 activation, but also through a novel FGFR-PLD-PKCδ-CREB cellular signaling pathway.

Local Allergic Inflammation in Chronic Rhinosinusitis With Nasal Polyps Could Influence on Disease Severity and Olfaction

Background and Objectives: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial disease resulting from inflammation of the nasal cavity and paranasal sinuses. Systemic allergic inflammation is an important cause of CRSwNP; however, the effect of local allergic inflammation is unclear. This study was designed to investigate the effect of local allergic inflammation in CRSwNP.Materials and Methods: The study included 11 patients with CRSwNP and 18 control subjects. Olfactory function was measured with the Korean Version of Sniffin’s stick test. Nasal lavage fluids (NLFs) were collected from all subjects and analyzed for total IgE, eosinophilic cationic protein (ECP), and cytokines (tumor necrosis factor [TNF]-α, interleukin [IL]-4, IL-10, IL-17A, interferon-γ). Flow cytometry was used to measure various inflammatory cells in the NAL fluids.Results: On analysis of flow cytometry and enzyme-linked immunosorbent assay, we found that CRSwNP patients had significantly increased eosinophil (%) and ECP levels in NLFs. In addition, there was significant local-systemic correlation between ECP level in NLFs and blood eosinophils (%) (r=0.391); however, there was no significant association between eosinophils (%) in NLFs and blood eosinophils. Moreover, in CRSwNP patients, the severity of disease was related with blood eosinophil (%), eosinophil (%), and ECP levels in NLFs, whereas olfactory function was associated with blood eosinophil (%) and ECP levels in NLFs.Conclusion: CRSwNP is a disease with high allergic inflammation that has negative impacts on the severity of disease and olfactory function. Therefore, we suggest that control of local allergic inflammation will be helpful to treat CRSwNP patients.

Serum and glucocorticoid-regulated kinase 1 regulates transforming growth factor β1-connective tissue growth factor pathway in chronic rhinosinusitis

PURPOSE

Serum/glucocorticoid-regulated kinase 1 (SGK1) has been identified as a crucial regulator in fibrotic disorders. Herein, we explored SGK1 role in tissue remodeling of chronic rhinosinusitis (CRS).

METHODS

Lentivirus was employed to generate an SGK1-overexpressing human bronchial epithelial cell (16HBE) line. To screen SGK1 downstream genes, RNA sequencing was performed on SGK1-overexpressing and control cell lines. To determine protein and gene expression levels, immunohistochemistry, western blotting, and quantitative real-time polymerase chain reaction were employed. Correlation analysis was performed using mRNA expression levels of SGK1, transforming growth factor β1 (TGF-β1), and connective tissue growth factor (CTGF) derived from CRS mucosal tissue and GEO database. Gene set enrichment analysis was conducted using gene sets from Molecular Signatures Database. The severity of symptoms in CRS patients was assessed using the 22-Item Sinonasal Outcome Test.

RESULTS

SGK1 overexpression significantly increased the expression of connective tissue growth factor (CTGF) in 16HBE cells (P < 0.01). Consistently, CTGF protein level was considerably greater in mucosal tissue of CRS without nasal polyps (CRSsNP) than in CRS with nasal polyps (CRSwNP) (P < 0.05) or in control subjects (P < 0.01). TGF-β1 protein level was higher in mucosal tissue of CRSsNP patients than in CRSwNP patients (P < 0.001) or in the control group (P < 0.01). mRNA levels of SGK1 and CTGF (P < 0.05, r = 0.668; P = 0.001, r = 0.630), TGF-β1 and CTGF (P < 0.05, r = 0.560; P < 0.05, r = 0.420), as well as SGK1 and TGF-β1(P < 0.05, r = 0.612; P < 0.05, r = 0.524) were significantly correlated in CRS mucosal tissue and GSE36830 dataset, respectively. TGF-β1-induced upregulated genes were significantly enriched in SGK1 overexpression group. In vitro assays, TGF-β1 promoted SGK1 and CTGF expression in a concentration- and time-dependent manner. Administrating an SGK1 inhibitor, GSK650394, significantly inhibited TGF-β1-induced CTGF expression in 16HBE and dispersed primary nasal polyp cells.

CONCLUSIONS

TGF-β1 stimulation significantly increases SGK1 and CTGF expression. By regulating TGF-β1-CTGF pathway, SGK1 may participate in tissue remodeling in the pathological mechanism of CRS.

Inflammatory Endotypes and Tissue Remodeling Features in Antrochoanal Polyps

Purpose

The pathogenic mechanisms of antrochoanal polyps (ACPs) remain largely unknown. This study aimed to characterize inflammatory patterns and tissue remodeling features in ACPs.

Methods

Inflammatory cell infiltration and tissue edema severity as well as fibrin deposition in ACPs and bilateral eosinophilic and noneosinophilic nasal polyps (NPs) were studied with immunohistochemical and immunofluorescence staining. Cytokine levels in sinonasal tissues were detected with the Bio-Plex assay. The expression of coagulation and fibrinolytic markers was measured using reverse-transcription polymerase chain reaction and enzyme-linked immunosorbent assays.

Results

Compared to control tissues and bilateral eosinophilic and noneosinophilic NPs, ACPs had higher levels of neutrophil infiltration and expression of myeloperoxidase (MPO), interleukin (IL)-8 and interferon (IFN)-γ. In total, 94.4% of ACPs demonstrated an eosinophil cationic protein/MPO ratio of < 1, compared to 79.0% of noneosinophilic and 26% of eosinophilic NPs. Principle component and multiple correspondence analyses revealed a neutrophilic and type 1 inflammation pattern in ACPs. Compared to control tissues, edema scores and fibrin deposition were increased, whereas d-dimer and tissue plasminogen activator (tPA) levels were decreased in ACPs and bilateral NPs, with more prominent changes in ACPs even than in eosinophilic NPs. The tPA levels were negatively correlated with IFN-γ, IL-8, and MPO levels in ACPs. Neutrophils were the major cellular source of IFN-γ in ACPs, and the number of IFN-γ⁺ neutrophils was elevated in ACPs than in control tissues and bilateral eosinophilic and noneosinophilic NPs.

Conclusions

ACPs are characterized by the neutrophilic and type 1 inflammation endotype. Neutrophil-derived IFN-γ is associated with reduced tPA production in ACPs.

Erythromycin reduces nasal inflammation by inhibiting immunoglobulin production, attenuating mucus secretion, and modulating cytokine expression

Allergic rhinitis (AR) and chronic rhinosinusitis (CRS) share some similar pathological mechanisms. In current study, we intend to investigate the impact of AR on CRS. In addition, we explored the efficacy of erythromycin (EM) treatment on CRS mice with or without AR (CRSwoAR, CRSwAR). Study subjects were divided into control, CRSwoAR, and CRSwAR groups. Experimental mice were divided similarly into control, CRSwoAR, and CRSwAR groups. In addition, CRS mice were treated with EM at 0.75, 7.5, or 75 mg/kg or with dexamethasone (Dex) at 1 mg/kg. In our results, allergy exacerbates inflammation that was evident in nasal histology and cytokine expression both in patients and in mice with CRS. Dex 1 mg/kg, EM 7.5 or 75 mg/kg treatments significantly inhibited serum IgE and IgG2a in CRS mice. EM-treated CRS mice had significantly elevated IL-10 levels and had a reversal of Th-1/Th-2 cytokine expression in nasal-associated lymphoid tissue. MUC5AC expressions were significantly reduced in the 7.5 or 75 mg/kg EM-treated mice compared with untreated mice. EM showed inhibitions on immunoglobulin production and mucus secretion stronger than Dex. We concluded that comorbid AR enhanced inflammation of CRS. EM and Dex treatments showed similar anti-inflammatory effects on CRS but through partly different mechanisms.

Chronic Rhinosinusitis and Alzheimer's Disease-A Possible Role for the Nasal Microbiome in Causing Neurodegeneration in the Elderly

Among millions of sufferers of chronic rhinosinusitis (CRS), the challenge is not only constantly coping with CRS-related symptoms, such as congested nose, sinus pain, and headaches, but also various complications, such as attention difficulties and possible depression. These complications suggest that neural activity in the central nervous system may be altered in those patients, leading to unexpected conditions, such as neurodegeneration in elderly patients. Recently, some studies linked the presence of CRS and cognitive impairments that could further develop into Alzheimer’s disease (AD). AD is the leading cause of dementia in the elderly and is characterised by progressive memory loss, cognitive behavioural deficits, and significant personality changes. The microbiome, especially those in the gut, has been recognised as a human organ and plays an important role in the development of various conditions, including AD. However, less attention has been paid to the microbiome in the nasal cavity. Increased nasal inflammatory responses due to CRS may be an initial event that changes local microbiome homeostasis, which may further affect neuronal integrity in the central nervous system resulting in AD. Evidence suggests a potential of β-amyloid deposition starting in olfactory neurons, which is then expanded from the nasal cavity to the central nervous system. In this paper, we reviewed currently available evidence that suggests this potential mechanism to advise the need to investigate the link between these two conditions.

Sinonasal Tissue Remodelling during Chronic Rhinosinusitis

The purpose of this review is to summarise contemporary knowledge of sinonasal tissue remodelling during chronic rhinosinusitis (CRS), a chronic disease involving long-term inflammation of the paranasal sinuses and nasal passage. The concept of tissue remodelling has significant clinical relevance because of its potential to cause irreversibility in chronic airway tissues. Recent studies have indicated that early surgical treatment of CRS may improve clinical outcome. Tissue remodelling has been described in the literature extensively with no consensus on how remodelling is defined. This review describes various factors implicated in establishing remodelling in sinonasal tissues with a special mention of asthma as a comorbid condition. Some of the main histological features of remodelling include basement membrane thickening and collagen modulation. This may be an avenue of research with regard to targeted therapy against remodelling in CRS.

Microbiome of Unilateral Chronic Rhinosinusitis: A Controlled Paired Analysis

The sinonasal microbiota in human upper airway may play an important role in chronic rhinosinusitis (CRS). Thus, this study aimed to investigate the human upper airway microbiome in patients with unilateral CRS, and compare the sinonasal microbiome of the unilateral diseased site with that of a contralateral healthy site. Thirty samples, 15 each from the diseased and healthy sites, were collected from the middle meatus and/or anterior ethmoid region of 15 patients with unilateral CRS during endoscopic sinus surgery. DNA extraction and bacterial microbiome analysis via 16S rRNA gene sequencing were then performed. Corynebacterium showed the highest relative abundance, followed by Staphylococcus in samples from both the diseased and healthy sites. Further, the relative abundances of Staphylococcus and Pseudomonas were significantly lower in samples from diseased sites than in those from healthy sites. Conversely, anaerobes, including Fusobacterium, Bacteroides, and Propionibacterium, were abundantly present in samples from both sites, more so in samples from diseased sites. However, the sites showed no significant difference with respect to richness or diversity (p > 0.05). Our results indicate that CRS might be a polymicrobial infection, and also suggest that Corynebacterium and Staphylococcus may exist as commensals on the sinus mucosal surface in the upper respiratory tract.

Desmopressin effects on bleeding during functional endoscopic sinus surgery on patients with chronic rhinosinusitis

OBJECTIVE

In this study we aimed to determine whether Desmopressin (DDAVP) can alter bleeding and improves surgeon visual field and decrease operation time or lessen use of anesthesiology medication in a clinical trial study.

METHOD

This study is a randomized clinical trial using the permuted block randomization method. 44 patients were enrolled in study and divided into two equal intervention-control groups. The intervention group received maximum dose of 0/2 micrograms per kg of DDAVP. In the control group, 30 min before the surgery, 100 ml of normal saline will be injected.

RESULTS

The amount of bleeding was 517/17 cc in control group during surgery while it was 387/72 cc in group receiving DDAVP which is significantly lower. The satisfaction of surgeon regarding suitable visual field was 6/45 in control group while it was 3/77 in DDAVP receivers which is lower.

CONCLUSION

It seems that intravenous DDAVP can reduce bleeding during surgery and offer an enhanced vision for surgeon during surgery but it has no potential efficacy on reduction of period of surgery and need for anesthesiology medication like remifentanil and isoflurane.

CD4 + T cells in inflammatory diseases : pathogenic T-helper cells and the CD69-Myl9 system

CD4 + T cells direct immune responses against infectious microorganisms but are also involved in the pathogenesis of inflammatory diseases. In the last two to three decades, various researchers have identified and characterized several functional CD4 + T cell subsets, including T-helper 1 (Th1), Th2, Th9 and Th17 cells and regulatory T (Treg) cells. In this mini-review, we introduce the concept of pathogenic Th cells that induce inflammatory diseases with a model of disease induction by a population of pathogenic Th cells; "pathogenic Th population disease-induction model". We will focus on Th2 cells that induce allergic airway inflammation-pathogenic Th2 cells (Tpath2 cells)-and discuss the nature of Tpath2 cells that shape the pathology of chronic inflammatory diseases. Various Tpath2 cell subsets have been identified and their unique features are summarized in mouse and human systems. Second, we will discuss how Th cells migrate and are maintained in chronic inflammatory lesions. We propose a model known as the "CD69-Myl9 system". CD69 is a cell surface molecule expressed on activated T cells and interaction with its ligand myosin light chain 9 (Myl9) is required for the induction of inflammatory diseases. Myl9 molecules in the small vessels of inflamed lungs may play a crucial role in the migration of activated T cells into inflammatory lesions. Emerging evidence may provide new insight into the pathogenesis of chronic inflammatory diseases and contribute to the development of new therapeutic strategies for intractable inflammatory disorders.

Bacteriological analysis of selected phenotypes of chronic rhinosinusitis with co-existing asthma, allergy and hypersensitivity to non-steroidal anti-inflammatory drugs

Introduction

Chronic rhinosinusitis (CRS) is one of the commonest chronic diseases. It is a systemic disease caused by many factors, including bacterial infections. There are two main types of CRS phenotypes: with polyps (CRSwNP) and without polyps (CRSsNP).

Aim

Analysis of sinus mucosal microbiome in patients with CRS depending on the phenotype. Investigating a possible link between the type of bacterial flora and the coexistence of diseases present in the CRS (asthma, allergy or hypersensitivity to non-steroidal anti-inflammatory drugs (NSAIDs) as well as the number of performed operations.

Material and methods

The authors conducted a retrospective study of the bacterial flora of the nasal cavity in patients with CRS operated endoscopically from March 2016 to June 2017. The study consisted od 222 women and 248 men. On the basis of an endoscopic examination, patients were qualified for the phenotype with or without polyps. Based on the medical interview patients were divided into group with asthma, allergy, NSAID hypersensitivity, first and repeated operations. The statistical analysis was made.

Results

There is no statistically significant relationship (p = 0.8519) between the CRS penotypes. In the group with CRSsNP, a statistically significant relationship was found between the observed flora and the coexistence of asthma (p = 0.0409), a trend towards significance was also noticed in the case of allergy (p = 0.0947). There was no relationship between the flora and NSAID hypersensitivity (p = 0.7356). In the group of CRSwNP patients, no statistically significant relationship was found between the observed bacterial flora and the presence of asthma (p = 0.7393), hypersensitivity to drugs (p = 0.1509) or allergy (p = 0.7427). There is no statistical significance between the occurrence of particular flora and the multiplicity of operations in both the CRSwNP (p = 0.4609) and CRSsNP phenotypes (p = 0.2469).

Conclusions

Gram-positive cocci were equally common in CRSwNP and CRSsNP. In the CRSsNP, there was a correlation between the coexistence of asthma and allergy, and the presence of Gram-positive cocci. There was no statistical significance between the occurrence of particular flora and the multiplicity of operations in both CRS phenotypes.

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.

Role of periostin in ECRS

Periostin, an extracelluar matrix protein belonging to the fasciclin family, has been reported to play a key role in the process of Th2-inflammation disease. As eoshinophilic chronic rhinosinusitis has a higher incident rate, studies show that periostin has participated in the process of inflammation and remodeling. This review mainly to summarize researches of periostin in ECRS and to investigate the clinical significance and expression of periostin.

Biologics for severe uncontrolled chronic rhinosinusitis with nasal polyps: a change management approach. Consensus of the Joint Committee of Italian Society of Otorhinolaryngology on biologics in rhinology

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogeneous inflammatory condition of nasal mucosa and paranasal sinuses, predominantly mediated by type 2 inflammation and often associated with comorbid asthma and/or Exacerbated Respiratory Disease (N-ERD). The standard of care involves local and systemic corticosteroids and/or sinonasal surgery, although these options may be associated with recurrences and patients may require revision surgery. Difficult-to-treat patients, in fact, have a more severe disease requiring high systemic corticosteroid use and/or multiple sinonasal surgeries. Literature data suggests that biologic agents targeting specific key effectors of type 2 inflammation may offer supplemental therapy for patients with severe and uncontrolled CRSwNP, leading to significant improvement in several outcomes. For these reasons, over the years the endotyping of the disease has become increasingly important. Herein, we provide not only an update on the existing studies about the most promising biologics in CRSwNP, but also critical discussion on controversies about the use of biologics in severe uncontrolled CRSwNP. We finally provide consensus on strategic issues gathered among experts of the Joint Committee of Italian Society of Otorhinolaryngology on biologics in order to offer the best care for difficult to treat patients.

CD133, a Progenitor Cell Marker, is Reduced in Nasal Polyposis and Showed Significant Correlations with TGF-β1 and IL-8

Introduction  Combination of chronic inflammation and an altered tissue remodeling process are involved in the development of Chronic Rhinosinusitis with Nasal Polyps (CRSwNP). Studies demonstrated that mesenchymal stem cells expressing the progenitor gene CD133 were involved in a significant reduction of the chronic inflammatory process in the polypoid tissue.

Objective  To evaluate the levels of CD133 (Prominin-1) in nasal polypoid tissue and its correlation with interleukin-8 (IL-8) and transforming growth factor β1 (TGF-β1).

Methods  A total of 74 subjects were divided in the following groups: control group ( n  = 35); chronic rhinosinusitis with nasal polyps nonpresenting comorbid asthma and aspirin intolerance (CRSwNPnonAI) group ( n  = 27); and chronic rhinosinusitis with nasal polyps presenting comorbid asthma and aspirin intolerance (CRSwNPAI) group ( n  = 12). Histologic analysis and also evaluation of the concentration of CD133, IL-8, and TGF-β1 by enzyme-linked immunosorbent assay (ELISA) kits were performed in nasal tissue obtained from nasal polypectomy or from middle turbinate tissue.

Results  Higher eosinophilic infiltration was found in both CRSwNP groups by histologic analysis. Lower levels of TGF-β1 and IL-8 were observed in both CRSwNP groups when compared with the control group, whereas the CD133 levels were significantly reduced only in the CRSwNPnonAI group compared with the control group.

Conclusion  It was demonstrated that the nasal mucosa presenting polyposis showed a significant reduction of CD133 levels, and also that this reduction was significantly correlated with the reduction of TGF-β1 levels, but not with IL-8 levels. Therefore, these findings may be involved in the altered inflammatory and remodeling processes observed in the nasal polyposis.

Serum, Whole Blood, Hair, and Mucosal Essential Trace Element and Mineral Levels in Children with Verified Chronic Rhinosinusitis Undergoing Functional Endoscopic Sinus Surgery

The objective of the present study was to assess hair, serum, whole blood, and excised tissue essential element content in children with chronic rhinosinusitis (CRS). Eighty-eight children with chronic rhinosinusitis and 66 healthy controls were enrolled in the present study. Evaluation of endoscopic Lund-Kennedy and computed tomography Lund-Mackay scores, as well as tissue sampling, was performed only in children with chronic rhinosinusitis. Assessment of Sino-Nasal Outcome Test-20 (SNOT-20) scores was performed in both cases and controls. Hair, whole blood, blood serum, and excised mucosal tissue (only in patients) analysis was performed using inductively coupled argon plasma mass-spectrometry. The obtained data demonstrate that whole blood Ca, Mg, Se, and Zn, as well as hair Ca, Cu, Mg, and Zn levels in the examined patients were significantly lower as compared with the control values. Only serum Zn concentration in children with CRS exceeded the respective control values, whereas serum Cu levels only tended to decrease in CRS. In turn, hair Fe content in children with CRS exceeded that in healthy controls. Regression analysis demonstrate that hair Ca levels, as well as whole blood Ca, Se, and Zn concentrations, were considered as negative predictors, whereas increased hair iron level was significantly directly associated with CRS. Significant associations between hair, serum, whole blood, and tissue element levels and Lund-Kennedy and Lund-Mackay scores were also revealed. Generally, the obtained data demonstrate that chronic rhinosinusitis is associated with impaired essential metal levels in pediatric patients with chronic rhinosinusitis. The observed alterations may contribute to CRS pathogenesis through modulation of mucociliary clearance, immunity, inflammatory response, and redox environment.

The tumor necrosis factor family molecules LIGHT and lymphotoxins in sinus mucosa of patients with chronic rhinosinusitis with or without nasal polyps

BACKGROUND

Little is known about the role of lymphotoxins (LTs) family in the sinonasal mucosa of patients with chronic rhinosinusitis (CRS). This study aims at investigating the expression of LIGHT, LTα, LTβ, and their receptors, LTβR and HVEM in normal and inflammatory sinus mucosa, and the effect of LIGHT and LTalpha1beta2 on chemokine secretion in epithelial cells, epithelial permeability, and leukocyte migration.

MATERIAL AND METHODS

The expression of LTs family in sinonasal mucosa was evaluated with real-time PCR, immunohistochemistry, and western blot. In LTβR, HVEM siRNA, or control siRNA-transfected epithelial cells treated with LIGHT or LTalpha1beta2, the expression of chemokines, the epithelial permeability, and the expression of junctional complex proteins were evaluated using real-time PCR, ELISA, western blot, confocal microscopy, and FITC-dextran. In cultured endothelial cells treated with LIGHT or LTalpha1beta2, the expression of ICAM-1 and VCAM-1, and leukocyte migration were elucidated.

RESULTS

LTs family was expressed in normal mucosa and their levels were increased in inflammatory mucosa of CRS patients. Recombinant LIGHT and LTalpha1beta2 induced chemokine secretion, increased epithelial permeability, and promoted leukocyte migration. However, the activity of LIGHT and LTalpha1beta2 was attenuated in cells transfected with LTβR and HVEM siRNA.

CONCLUSIONS

LIGHT and LTs may participate in the ongoing process of chronic inflammation, inducing chemokine secretion, leukocyte migration, and dysregulated epithelial barrier through LTβR and HVEM in sinonasal mucosa.

Regulation of eosinophil functions by autophagy

Eosinophils are granule-containing leukocytes which develop in the bone marrow. For many years, eosinophils have been recognized as cytotoxic effector cells, but recent studies suggest that they perform additional immunomodulatory and homeostatic functions. Autophagy is a conserved intracellular process which preserves cellular homeostasis. Autophagy defects have been linked to the pathogenesis of many human disorders. Evidence for abnormal regulation of autophagy, including decreased or increased expression of autophagy-related (ATG) proteins, has been reported in several eosinophilic inflammatory disorders, such as Crohn's disease, bronchial asthma, eosinophilic esophagitis, and chronic rhinosinusitis. Despite the increasing extent of research using preclinical models of immune cell-specific autophagy deficiency, the physiological relevance of autophagic pathway in eosinophils has remained unknown until recently. Owing to the increasing evidence that eosinophils play a role in keeping organismal homeostasis, the regulation of eosinophil functions is of considerable interest. Here, we discuss the most recent advances on the role of autophagy in eosinophils, placing particular emphasis on insights obtained in mouse models of infections and malignant diseases in which autophagy has genetically dismantled in the eosinophil lineage. These studies pointed to the possibility that autophagy-deficient eosinophils exaggerate inflammation. Therefore, the pharmacological modulation of the autophagic pathway in these cells could be used for therapeutic interventions.

Safety review of current systemic treatments for severe chronic rhinosinusitis with nasal polyps and future directions

Introduction: Chronic rhinosinusitis is a common condition characterized by inflammation of the nasal and sinus linings, rhinorrhea, nasal blockage, facial pain, and loss of sense of smell for longer than 12 weeks. CRS can occur with or without nasal polyps.Areas covered: First-line treatment in chronic rhinosinusitis with nasal polyps is long-term intranasal corticosteroids, which have few adverse events associated with their use, as second-generation intranasal corticosteroids having a bioavailability of <0.5%. Systemic corticosteroids are used when intranasal steroids fail to achieve symptom control. However, the repeated use of oral corticosteroids is associated with numerous adverse events and the benefit from a course of oral corticosteroids is lost within three to six months.Expert opinion: Antibiotics are commonly prescribed in nasal polyposis although there is also very little evidence for their use outside of acute infection. Macrolide antibiotics are also associated with a transient increase in the risk of arrhythmias. Biologics offer a steroid-sparing alternative to the treatment of severe nasal polyposis. They have shown to be relatively well tolerated in studies to date; however, studies suggest that there is no disease modifying effect and that any benefit is lost within weeks of finishing treatment.

Septum submucosal glands exhibit aberrant morphology and reduced mucin production in chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) is characterized by significant accumulation and thickening of mucus in the sinonasal cavities. One contributor of aberrant mucus production and impaired mucociliary clearance (MCC) is altered function of the sinonasal submucosal glands (SMGs), yet contributions of SMGs to upper airway disease initiation and progression remain unknown. The objective of this study was to characterize the morphology and secretory cell identities of the nasal septum SMGs in both healthy and CRS adults.

METHODS

Biopsies from adult participants with CRS without nasal polyps (CRSsNP, n = 4), CRS with nasal polyps (CRSwNP, n = 8), and non-CRS controls (n = 14) were collected from the posterior septum. Glandular morphology and mucus markers were investigated using histological techniques and high-resolution confocal microscopy.

RESULTS

Analysis revealed a significant decrease in gland density in the posterior septum of CRSsNP (28% ± 6.15%) and CRSwNP (23% ± 3.09%) compared to control participants (53% ± 1.59%, p < 0.0001). Further analysis of the CRS SMG secretory function revealed an overall decrease in Mucin 5B+ gland mucus being produced. Dilated and cystic ductal structures filled with inspissated mucus were also common to CRS glands.

CONCLUSION

Here, we describe a significant alteration in SMG structure and function in the adult CRS posterior septum suggesting reduced gland contribution to MCC. The SMGs of both the nose and sinuses may represent targets for future therapeutic approaches.

Defective STING expression potentiates IL-13 signaling in epithelial cells in eosinophilic chronic rhinosinusitis with nasal polyps

BACKGROUND

Stimulator of interferon genes (STING) activation favors effective innate immune responses against viral infections. Its role in chronic rhinosinusitis with nasal polyps (CRSwNP) remains unknown.

OBJECTIVE

Our aim was to explore the expression, regulation, and function of STING in CRSwNP.

METHODS

STING expression in sinonasal mucosal samples was analyzed by means of quantitative RT-PCR, immunohistochemistry, flow cytometry, and Western blotting. Regulation and function of STING expression were explored by using cultured primary human nasal epithelial cells (HNECs) and cells of the line BEAS-2B in vitro.

RESULTS

STING expression was reduced in eosinophilic nasal polyps compared with that in noneosinophilic nasal polyps and control tissues. STING was predominantly expressed by epithelial cells in nasal tissue and was downregulated by IL-4 and IL-13 in a signal transducer and activator of transcription 6 (STAT6)-dependent manner. HNECs derived from eosinophilic polyps displayed compromised STING-dependent type I interferon production but heightened IL-13-induced STAT6 activation and CCL26 production as compared with HNECs from noneosinophilic polyps and control tissues, which were rescued by exogenous STING overexpression. Knocking down or overexpressing STING decreased or enhanced expression of suppressor of cytokine signaling 1 (SOCS1) in BEAS-2B cells, respectively, independent of the canonic STING pathway elements TBK1 and IRF3. Knocking down SOCS1 abolished the inhibitory effect of STING on IL-13 signaling in BEAS-2B cells. STING expression was positively correlated with SOCS1 expression but negatively correlated with CCL26 expression in nasal epithelial cells from patients with CRSwNP.

CONCLUSIONS

Reduced STING expression caused by the type 2 milieu not only impairs STING-dependent type I interferon production but also amplifies IL-13 signaling by decreasing SOCS1 expression in nasal epithelial cells in eosinophilic CRSwNP.

Elevated microRNA-21 Is a Brake of Inflammation Involved in the Development of Nasal Polyps

Background

CRSwNP is an inflammatory disease but the mechanism is not yet fully understood. MiR-21, a member of miRNAs, has been reported to play roles in mediating inflammation. However, the expression of miR-21 and its role in patients with CRSwNP remain elusive.

Methods

Turbinates from control subjects, uncinate processes from CRSsNP, polyp tissues from CRSwNP, and nasal epithelial cells brushed from nasal mucosa were collected. The expression of miR-21 and cytokines in nasal tissues and epithelial cells were detected by qPCR. The localization of miR-21 was detected by ISH, and its target was identified by bioinformation analysis, qPCR, IHC, WB, and luciferase reporter system. The protein and mRNA of PDCD4 and NF-κB P65 were determined by WB and qPCR after miR-21 transfection in HNEpC. The role of miR-21 on cytokines was analyzed in HNEpC and nasal polyp explants.

Results

MiR-21 was upregulated in CRSwNP relative to control subjects by qPCR, which was determined mainly in nasal epithelial cells of CRSwNP by ISH. Both pro-inflammation cytokines (IL-1β, IL-6, IL-8, IL-25, and TSLP) and a suppressive cytokine (IL-10) were overexpressed in the epithelial cells of CRSwNP. The expression of miR-21 was positively correlated with IL-10 and negatively correlated with IL-6, IL-8, IL-33, and TSLP in the epithelial cells of CRSwNP. As a potential target of miR-21, the expression of PDCD4 was negatively correlated with miR-21 in CRSwNP. In HNEpC, miR-21 could reduce the expression of PDCD4 at both mRNA and protein levels, and bioinformation analysis and luciferase reporter system confirmed PDCD4 as one target of miR-21. Furthermore, miR-21 could decrease the activation of NF-κB and increase IL-10 mRNA. Both SEB and LPS could elevate miR-21, with IL-25, IL-33, TSLP induced by SEB and IL-1β, IL-6, IL-8 induced by LPS, while the miR-21 could regulate the expression of IL-33, TSLP, IL-1β, IL- 6 and IL-8 in vitro and ex vivo. Clinically, miR-21 expression was inversely correlated with the Lund-Mackay CT scores and the Lund-Kennedy scores in CRSwNP.

Conclusion

MiR-21 could be a prominent negative feedback factor in the inflammation process to attenuate the expression of pro-inflammatory cytokines, thereby playing an anti-inflammation role in CRSwNP.

Role of intracellular zinc in molecular and cellular function in allergic inflammatory diseases

Zinc is an essential micronutrient in human body and a vital cofactor for the function of numerous proteins encoded by the human genome. Zinc has a critical role in maintaining many biochemical and physiological processes at the molecular, cellular, and multiple organ and systemic levels. The alteration of zinc homeostasis causes dysfunction of many organs and systems. In the immune system, zinc regulates the differentiation, proliferation and function of inflammatory cells, including T cells, eosinophils, and B cells, by modifying several signaling pathways such as NFκB signaling pathways and TCR signals. An adequate zinc level is essential for proper immune responses and decreased zinc levels were reported in many allergic inflammatory diseases, including atopic dermatitis, bronchial asthma, and chronic rhinosinusitis. Decreased zinc levels often enhance inflammatory activation. On the other hand, the inflammatory conditions alter the intracellular homeostasis of zinc, often decreasing zinc levels. These findings implied that there could be a vicious cycle between zinc deficiency and inflammatory conditions. In this review, we present recent evidence on the involvement of zinc in atopic dermatitis, bronchial asthma, and chronic rhinosinusitis, with insights into the involvement of zinc in the underlying molecular and cellular mechanisms related to these allergic inflammatory diseases.

IL-19 induced by IL-13/IL-17A in the nasal epithelium of patients with chronic rhinosinusitis upregulates MMP-9 expression via ERK/NF-κB signaling pathway

Background

Tissue remodeling is a crucial characteristic of chronic rhinosinusitis (CRS). Imbalance between matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) is crucial for the pathologic tissue remodeling in CRS. Elevation of interleukin (IL)‐19 or MMP‐9 levels in patients with CRS had been proven in previous studies. Here, we aimed to investigate the role of IL‐19 in mediating MMP‐9 expression in CRS.

Methods

Nasal tissue samples were collected from 45 individuals having chronic rhinosinusitis with nasal polyps (CRSwNP), 24 CRS without nasal polyps (CRSsNP), and 17 controls. Expression of IL‐19, its receptors (IL‐20R1/IL‐20R2), and MMP‐9 were investigated using RT‐qPCR and Immunofluorescence (IF). Human nasal epithelial cells (HNECs) were stimulated by IL‐19; ERK phosphorylation, nuclear factor‐κB (NF‐κB) pathway activation, and MMP‐9 level were detected by RT‐qPCR, enzyme‐linked immunosorbent assay, western blot, and IF. We also explored the effect of type1/2/3 cytokines on IL‐19 production by RT‐qPCR, and western blot.

Results

Expression levels of IL‐19, its receptors (IL‐20R1/IL‐20R2), and MMP‐9 were increased in nasal tissues from individuals with CRSwNP compared to those with CRSsNP as well as the controls. IL‐19 significantly elevated the production of MMP‐9 in HNECs. Furthermore, IL‐19 could activate the ERK and NF‐κB pathways, accompanied by increased MMP‐9 production in HNECs. Conversely, both ERK and NF‐κB inhibitors significantly attenuated the role of IL‐19 in MMP‐9 production. siRNA knockdown of IL‐20R1 suppressed ERK and NF‐κB pathway activation, thereby decreasing MMP‐9 expression. IL‐13 and IL‐17A were found to stimulate IL‐19 production in HNECs.

Conclusion

IL‐19, promoted by IL‐13 and IL‐17A, contributes to the upregulation of secretion of the tissue remodeling factor MMP‐9 in patients with CRS.

Paranasal sinusitis at the initiation of chemotherapy is a risk factor for invasive fungal disease in children and adolescents with cancer

BACKGROUND

The impact of paranasal sinusitis on the clinical outcome of patients with cancer remains unknown. The aim of this study was to determine whether paranasal sinusitis at the initiation of chemotherapy (SAI) affects the development of infectious complications in children and adolescents with cancer.

METHODS

A retrospective cohort analysis of patients aged 0-20 years with cancer who received chemotherapy was performed. SAI was defined as the presence of a fluid level or mucosal swelling or total opacity on sinus computed tomography examination before the initiation of chemotherapy. The primary outcome measures were the incidence of bacteremia, septic shock, and invasive fungal disease (IFD, including proven, probable, and possible cases).

RESULTS

SAI was observed in 57 (44%) of 130 enrolled patients. There were no significant differences in age, sex, and disease distribution between the patients with SAI (SAI group) and those without (non-SAI group). There was no significant difference in the 1-year cumulative incidence of bacteremia or septic shock after treatment initiation between the two groups (bacteremia, SAI group 33% vs. non-SAI group 35%, P = 0.53; septic shock, SAI group 4% vs. non-SAI group 4%, P = 0.87). The 1-year cumulative incidence of IFD was higher in the SAI group than in the non-SAI group (22% vs. 6%, P = 0.012). Cumulative incidence analysis after inverse probability of treatment weighting adjustment showed that the SAI group was more likely to develop IFD (HR: 3.5, 95% CI: 1.1-11.2, P = 0.033).

CONCLUSIONS

Our findings suggest that patients with SAI may be at higher risk for IFD during chemotherapy.

Magnetic Resonance Imaging Detects Chronic Rhinosinusitis in Infants and Preschool Children with Cystic Fibrosis

Rationale: Chronic rhinosinusitis (CRS) contributes to disease burden of patients with cystic fibrosis (CF). However, its onset and progression in infants and preschool children with CF remain poorly understood.Objectives: To determine the prevalence and extent of CRS in young children with CF using magnetic resonance imaging (MRI).Methods: MRI was performed in sedation in 67 infants and preschool children with CF (mean age 2.3 ± 2.1 yr; range 0-6 yr) and 30 non-CF control subjects (3.5 ± 2.0 yr; range 0-6 yr). Paranasal sinus dimensions and structural abnormalities, including mucosal swelling; mucopyoceles; and nasal polyps of the maxillary, frontal, sphenoid, and ethmoid sinuses; and, in addition, medial maxillary sinus wall deformation, were assessed using a dedicated CRS MRI scoring system.Results: Pneumatization and dimensions of paranasal sinuses did not differ between the two groups. MRI detected an increased prevalence of mucosal swelling (83% vs. 17%; P < 0.001), mucopyoceles (75% vs. 2%; P < 0.001), polyps (26% vs. 7%; P < 0.001), and maxillary sinus wall deformation (68% vs. 2%; P < 0.001) in infants and preschool children with CF compared with age-matched control subjects. Furthermore, the extent of these abnormalities was also increased with a MRI sum score of 22.9 ± 10.9 in CF compared with 4.5 ± 7.6 in non-CF control subjects (P < 0.001).Conclusions: MRI detected normal dimensions of paranasal sinuses, and a high prevalence and severity of paranasal sinus abnormalities due to CRS in infants and preschool children with CF without radiation exposure. Our results support the development of MRI for sensitive noninvasive diagnosis and monitoring of CRS in young children with CF, and as outcome measures for clinical trials.Clinical trial registered with www.clinicaltrials.gov (NCT00760071).

International consensus statement on allergy and rhinology: rhinosinusitis 2021

I.

EXECUTIVE SUMMARY

BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document.

METHODS

ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary.

RESULTS

ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided.

CONCLUSION

This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.

Chronic rhinosinusitis with nasal polyps is associated with impaired TMEM16A-mediated epithelial chloride secretion

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is one of the most common chronic disorders with limited therapeutic options. However, the pathogenesis of CRSwNP remains poorly understood.

OBJECTIVE

We sought to determine the role of abnormalities in nasal epithelial ion transport in primary epithelial cultures and patients with CRSwNP.

METHODS

We studied epithelial ion transport and transcript levels of the Cl^- channels cystic fibrosis transmembrane conductance regulator and transmembrane protein 16A (TMEM16A) in human primary nasal epithelial cultures of patients with CRSwNP and healthy controls. Furthermore, we determined expression levels of proinflammatory cytokines that have been implicated in the regulation of epithelial ion channels (IL-1β, INF-γ, TNF-α, IL-13) and studied effects of the key T_H2 signaling molecule IL-13 in CRSwNP and control nasal epithelial cultures. Finally, we measured in vivo nasal potential difference to compare epithelial ion transport in patients with CRSwNP and controls.

RESULTS

Bioelectric studies demonstrated that Ca²⁺-activated Cl^- secretion was reduced in CRSwNP versus control nasal epithelial cultures. Transcript levels of IL-13 and the Ca²⁺-activated Cl^- channel TMEM16A were increased in CRSwNP cultures. Stimulation with IL-13 increased TMEM16A expression further and restored Ca²⁺-activated Cl^- secretion in CRSwNP cultures. Nasal potential difference measurements demonstrated reduced Ca²⁺-activated Cl^- transport in patients with CRSwNP versus controls.

CONCLUSIONS

This study demonstrates that TMEM16A-mediated Ca²⁺-activated Cl^- secretion is reduced in primary nasal epithelial cultures and nasal epithelia of patients with CRSwNP. Our data suggest that the Ca²⁺-activated Cl^- channel TMEM16A may be implicated in the pathogenesis and serve as a novel therapeutic target in patients with CRSwNP.

Current Perspective on Nasal Delivery Systems for Chronic Rhinosinusitis

Chronic rhinosinusitis is an upper respiratory disease during which topical drug treatment via the nasal cavity is the most actively utilized therapeutic strategy. In addition to steroids, antibiotics, and antifungal agents, which are widely used in clinical practice, research on novel topical agents to improve the bacterial biofilm or mucociliary clearance remains ongoing. Moreover, owing to the complex structure of the nasal cavity, the effects of nasal drug delivery vary depending on factors related to delivery fluid dynamics, including device, volume, and compounds. In this article, we review methods and compounds that have been applied to chronic rhinosinusitis management and introduce recent advances and future perspectives in nasal drug delivery for upper respiratory diseases.

Association of Air Pollutant Exposure and Sinonasal Histopathology Findings in Chronic Rhinosinusitis

BACKGROUND

Ambient air pollution is well known to cause inflammatory change in respiratory epithelium and is associated with exacerbations of inflammatory conditions such as asthma and chronic obstructive pulmonary disease. However, limited work has been done on the impact of air pollution on pathogenesis of chronic rhinosinusitis and there are no reports in the literature of how pollutant exposure may impact sinonasal histopathology in patients with chronic rhinosinusitis.

OBJECTIVE

This study aims to identify associations between certain histopathologic characteristics seen in sinus tissue of patients with chronic rhinosinusitis (CRS) and levels of particulate air pollution (PM_2.5) and ground-level ozone in their place of residence.

METHODS

A structured histopathology report was created to characterize the tissues of CRS patients undergoing sinus surgery. An estimate for each patient's exposure to air pollutants including small particulate matter (PM_2.5) and ground-level ozone was obtained using the Environmental Protection Agency's (EPA) Environmental Justice Screening and Mapping Tool (EJSCREEN). Mean pollutant exposures for patients whose tissues exhibited varying histopathologic features were compared using logistic regression models.

RESULTS

Data from 291 CRS patients were analyzed. Higher degree of inflammation was significantly associated with increased ozone exposure (p = 0.031). Amongst the patients with CRSwNP (n=131), presence of eosinophilic aggregates (p = 0.018) and Charcot-Leyden crystals (p = 0.036) was associated with increased ozone exposure.

CONCLUSION

Exposure to ambient air pollutants may contribute to pathogenesis of CRS. Increasing ozone exposure was linked to both higher tissue inflammation and presence of eosinophilic aggregates and Charcot-Leyden crystals in CRSwNP patients.