Upper and lower airway remodelling mechanisms in asthma, allergic rhinitis and chronic rhinosinusitis: The one airway concept revisited

Proteomic and metabolomic proof of concept for unified airways in chronic rhinosinusitis and asthma

BACKGROUND

The pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) with comorbid asthma remains unclear.

OBJECTIVE

To assess upper and lower airway unity and identify a possible common pathogenesis in CRSwNP with asthma.

METHODS

This study analyzed the expression of proteins and metabolites in nasal lavage fluid cells (NLFCs) and induced sputum cells (ISCs). Differentially expressed proteins and their function-related metabolites in the upper and lower airways of patients having CRSwNP with or without asthma were identified; relevant signaling pathways were analyzed, and key pathway-related proteins were identified. Parallel reaction monitoring was used to verify these target proteins.

RESULTS

Protein or metabolite expression between NLFCs and ISCs was highly correlated and conservative on the basis of expression profiles and weighted gene coexpression network analysis. There were 17 differentially coexpressed proteins and their function-related 13 metabolites that were identified in the NLFCs and ISCs of CRSwNP, whereas 11 proteins and 11 metabolites were identified in CRSwNP with asthma. An asthma pathway was involved in the copathogenesis of upper and lower airways in whether CRSwNP or CRSwNP with asthma. The asthma pathway-related proteins proteoglycan 2 and eosinophil peroxidase, as the core of the protein-metabolism interaction networks between the upper and lower airways, were both highly coexpressed in NLFCs and ISCs in patients having either CRSwNP or CRSwNP with asthma by parallel reaction monitoring validation.

CONCLUSION

Proteomics and metabolomics reveal upper and lower airway unity. Asthma pathway-related proteins proteoglycan 2 and eosinophil peroxidase from the upper airway could be used to assess the potential risk of lower airway dysfunction in CRSwNP.

Risk factor analysis and nomogram for predicting poor symptom control in smoking asthmatics

BACKGROUND

Smoking induces and modifies the airway immune response, accelerating the decline of asthmatics' lung function and severely affecting asthma symptoms' control level. To assess the prognosis of asthmatics who smoke and to provide reasonable recommendations for treatment, we constructed a nomogram prediction model.

METHODS

General and clinical data were collected from April to September 2021 from smoking asthmatics aged ≥14 years attending the People's Hospital of Zhengzhou University. Patients were followed up regularly by telephone or outpatient visits, and their medication and follow-up visits were recorded during the 6-months follow-up visit, as well as their asthma control levels after 6 months (asthma control questionnaire-5, ACQ-5). The study employed R4.2.2 software to conduct univariate and multivariate logistic regression analyses to identify independent risk factors for 'poorly controlled asthma' (ACQ>0.75) as the outcome variable. Subsequently, a nomogram prediction model was constructed. Internal validation was used to test the reproducibility of the model. The model efficacy was evaluated using the consistency index (C-index), receiver operating characteristic (ROC) curve, calibration curve, and decision curve.

RESULTS

Invitations were sent to 231 asthmatics who smoked. A total of 202 participants responded, resulting in a final total of 190 participants included in the model development. The nomogram established five independent risk factors (P<0.05): FEV1%pred, smoking index (100), comorbidities situations, medication regimen, and good or poor medication adherence. The area under curve (AUC) of the modeling set was 0.824(95%CI 0.765-0.884), suggesting that the nomogram has a high ability to distinguish poor asthma control in smoking asthmatics after 6 months. The calibration curve showed a C-index of 0.824 for the modeling set and a C-index of 0.792 for the self-validation set formed by 1000 bootstrap sampling, which means that the prediction probability of the model was consistent with reality. Decision curve analysis (DCA) of the nomogram revealed that the net benefit was higher when the risk threshold probability for poor asthma control was 4.5 - 93.9%.

CONCLUSIONS

FEV1%pred, smoking index (100), comorbidities situations, medication regimen, and medication adherence were identified as independent risk factors for poor asthma control after 6 months in smoking asthmatics. The nomogram established based on these findings can effectively predict relevant risk and provide clinicians with a reference to identify the poorly controlled population with smoking asthma as early as possible, and to select a better therapeutic regimen. Meanwhile, it can effectively improve the medication adherence and the degree of attention to complications in smoking asthma patients.

Efficacy and safety of dupilumab in the treatment of CRSwNP in the real-life setting: a review of the literature

INTRODUCTION

The recent approval of Dupilumab has profoundly revolutionized the management of patients affected by severe and recalcitrant Chronic Rhinosinusitis with Nasal Polyps (CRSwNP). However, a review that summarizes the results of real-life studies and compares them to phase 3 studies SINUS-24 and 52 is still lacking.

MATERIALS AND METHODS

A search of all real-life studies published from 2019 to 2023 was performed. Patients characteristics at baseline and 6 and 12 months after starting Dupilumab were extracted and compared to those from phase 3 trials: age, sex, smoking habits, comorbid asthma and aspirin-exacerbated respiratory disease (AERD), previous endoscopic sinus surgery (ESS), hematic eosinophils and total IgE, NasalAQ2 Polyps Score (NPS), smell, SNOT-22, adverse events (AEs), and response to treatment.

RESULTS

15 papers were included with an overall number of 1658 patients. A higher rate of comorbidities and previous ESS was found in patients from real-life studies. In addition, they had worse smell and SNOT-22 at baseline compared to patients from SINUS-24 and 52. Comorbid and post-ESS patients tended to have a faster NPS and SNOT-22 improvement, although the absolute values were not clinically relevant. A more extensive surgery and a number of ESS ≥ 2 were related to worse olfactory outcomes, probably due to iatrogenic damage. No correlation was found between hematic eosinophils and outcomes. AEs were reported by 12.4% of patients and 2.2% had to discontinue dupilumab. Weight gain was an emergent AE (0.8%), probably related to the restored sense of smell and taste. Non-responders were 3.5% and they were switched to systemic steroid, ESS, or another biologic.

CONCLUSION

Despite some differences in prescription criteria between countries, dupilumab was demonstrated to be effective even in the real-life scenario. However, emerging AEs and possible unknown long-term AEs of a likely lifelong therapy should be considered.

Updated epithelial barrier dysfunction in chronic rhinosinusitis: Targeting pathophysiology and treatment response of tight junctions

Tight junction (TJ) proteins establish a physical barrier between epithelial cells, playing a crucial role in maintaining tissue homeostasis by safeguarding host tissues against pathogens, allergens, antigens, irritants, etc. Recently, an increasing number of studies have demonstrated that abnormal expression of TJs plays an essential role in the development and progression of inflammatory airway diseases, including chronic obstructive pulmonary disease, asthma, allergic rhinitis, and chronic rhinosinusitis (CRS) with or without nasal polyps. Among them, CRS with nasal polyps is a prevalent chronic inflammatory disease that affects the nasal cavity and paranasal sinuses, leading to a poor prognosis and significantly impacting patients' quality of life. Its pathogenesis primarily involves dysfunction of the nasal epithelial barrier, impaired mucociliary clearance, disordered immune response, and excessive tissue remodeling. Numerous studies have elucidated the pivotal role of TJs in both the pathogenesis and response to traditional therapies in CRS. We therefore to review and discuss potential factors contributing to impair and repair of TJs in the nasal epithelium based on their structure, function, and formation process.

Matrix metalloproteinases in chronic rhinosinusitis

INTRODUCTION

Matrix metalloproteinases (MMPs) are a group of enzymes that are essential in maintaining extracellular matrix (ECM) homeostasis, regulating inflammation and tissue remodeling. In chronic rhinosinusitis (CRS), the overexpression of certain MMPs can contribute to chronic nasal tissue inflammation, ECM remodeling, and tissue repair.

AREAS COVERED

This review provides a comprehensive overview of the biological characteristics and functions of the MMP family, particularly focusing on the expression and activity of MMPs in patients with CRS, and delves into their role in the pathogenesis of CRS and their potential as therapeutic targets.

EXPERT OPINION

MMPs are important in tissue remodeling and have been implicated in the pathophysiology of CRS. Previous studies have shown that the expression of MMPs is upregulated in the nasal mucosa of patients with CRS and positively correlates with the severity of CRS. However, there is still a large gap in the research content of MMP in CRS, and the specific expression and pathogenic mechanism of MMP still need to be clarified. The significance and value of the ratio of MMP to tissue inhibitors of metalloproteinase (TIMP) in diseases still need to be demonstrated. Moreover, further studies are needed to assess the efficacy and safety of biologics that target MMPs in patients with CRS.

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.

Airborne indoor allergen serine proteases and their contribution to sensitisation and activation of innate immunity in allergic airway disease

Common airborne allergens (pollen, animal dander and those from fungi and insects) are the main triggers of type I allergic disorder in the respiratory system and are associated with allergic rhinitis, allergic asthma, as well as immunoglobulin E (IgE)-mediated allergic bronchopulmonary aspergillosis. These allergens promote IgE crosslinking, vasodilation, infiltration of inflammatory cells, mucosal barrier dysfunction, extracellular matrix deposition and smooth muscle spasm, which collectively cause remodelling of the airways. Fungus and insect (house dust mite and cockroaches) indoor allergens are particularly rich in proteases. Indeed, more than 40 different types of aeroallergen proteases, which have both IgE-neutralising and tissue-destructive activities, have been documented in the Allergen Nomenclature database. Of all the inhaled protease allergens, 85% are classed as serine protease activities and include trypsin-like, chymotrypsin-like and collagenolytic serine proteases. In this article, we review and compare the allergenicity and proteolytic effect of allergen serine proteases as listed in the Allergen Nomenclature and MEROPS databases and highlight their contribution to allergic sensitisation, disruption of the epithelial barrier and activation of innate immunity in allergic airways disease. The utility of small-molecule inhibitors of allergen serine proteases as a potential treatment strategy for allergic airways disease will also be discussed.

The cyclooxygenase-2 upregulation mediates production of PGE2 autacoid to positively regulate interleukin-6 secretion in chronic rhinosinusitis with nasal polyps and polyp-derived fibroblasts

Chronic rhinosinusitis (CRS) can be traditionally classified as CRSwNP [with nasal polyps (NPs)] and CRSsNP (without NPs) based on the clinical phenotypes but recently suggested to be classified by the endotypes. We have identified overexpression of the cyclooxygenase-2 (COX-2) gene in NP tissues of Taiwanese CRSwNP patients. Therefore, in this study, we sought to investigate its protein expression/location/distribution in NP specimens and explore its roles in nasal polyposis. The COX-2 protein and mRNA expression was found higher in NPs than that in the control and CRSsNP patients' nasal tissues, mainly located at the epithelium and subepithelial stroma. Consistently, the CRS-related peptidoglycan (PGN) and bradykinin provoked COX-2 mRNA and protein upregulation in the human NP-derived fibroblasts and caused PGE2, thromboxane A2 (TXA2), and interleukin (IL-6) secretion in culture medium. Further analysis revealed that the PI3K/Akt activation and COX-2 induction were necessarily required for PGN-induced IL-6 production/secretion and the induced PGE2, but not TXA2, was speculated to affect IL-6 protein trafficking and production. Finally, the IL-6 increase observed in vitro could also be detected in NP tissues. Collectively, we demonstrated here that COX-2 protein and IL-6 are overexpressed in human NP tissues. In response to PGN challenge, the PI3K/Akt activation and COX-2-mediated PGE2 autacoid correlates with extracellular IL-6 protein trafficking/production in NP-derived fibroblasts, which can additionally contribute to the production of Th17-related cytokines such as IL-17 and TNF-α. This study also suggests COX-2 as a special biomarker for CRSwNP endotyping and may highlight the importance of COX-2 inhibitors in treating CRSwNP.

Effectiveness of dupilumab versus endoscopic sinus surgery for the treatment of type-2 chronic rhinosinusitis with nasal polyps: a preliminary report

PURPOSE

Historically managed with intranasal corticosteroids (INCS) and endoscopic sinus surgery (ESS), type-2 Chronic RhinoSinusitis with Nasal Polyps (CRSwNP) treatment was revolutionized by the introduction of dupilumab but universally accepted guidelines are still lacking.

METHODS

Patients treated at our University Hospital for type-2 CRSwNP were enrolled. Demographic data were collected, as well as laboratory (eosinophils, total IgE), endoscopic [nasal polyps score (NPS), modified Lund-Kennedy score (mLKS)], radiological [Lund-Mackay score (LMS) at CT scan], SNOT-22, and olfactory [Sniffin' Sticks identification test (SSIT)] features. Patients were treated with dupilumab or ESS and re-evaluated after 3 and 12 months.

RESULTS

At 3 and 12 months, patients undergoing ESS achieved a higher reduction of NPS and mLKS, while patients receiving dupilumab experienced a higher improvement at SNOT-22 and SSIT with a greater positive variation in the prevalence of anosmia (- 57.7% vs - 42.9%) and normosmia (+ 37.8 vs + 28.5%). Mean mLKS and LMS were quite similar. Results were independent of clinical features known to contribute to CRSwNP severity, except for patients with ≥ 2 prior ESS who had a significantly lower smell improvement.

CONCLUSION

ESS and dupilumab were effective at reducing CRSwNP inflammatory burning. CRSwNP smell impairment cannot be attributed only to olfactory cleft obstruction and other mechanisms may be involved. Dupilumab acts systemically with poor correlation with NPS. As of today, dupilumab appears to be more suitable for elderly patients with anesthesiological contraindications and/or several previous surgeries, while ESS may represent the first-line choice in surgery-naive patients.

The role of ZEB1 in regulating tight junctions in antrochoanal polyp

Background

Antrochoanal polyp (ACP) is a benign nasal mass of unknown etiology. Tight junctions (TJs) are essential to the epithelial barrier that protects the body from external damage. However, the phenotype of tight junction in ACP is currently unclear.

Methods

The samples were collected from 20 controls, 37 patients with ACP and 45 patients with chronic rhinosinusitis with nasal polyp (CRSwNP). Quantitative Real-Time PCR (qRT-PCR) and immunofluorescence staining (IF) were performed to analyze the expressions of TJs markers (ZO-1, claudin-3 and occludin) and ZEB1. hNEpCs were transfected with ZEB1 small interfering RNA (si-ZEB1) or ZEB1 over-expression plasmid (OE-ZEB1). qRT-PCR and Western blotting were used to determine the levels of TJs-related markers. Primary human nasal epithelial cells (hNECs) were stimulated with IL-17A and si-ZEB1, and the expression of epithelial barrier markers were measured by qRT-PCR and Western blotting.

Results

Compared to the control group, ACP group showed a significant downregulation in both mRNA and protein levels of ZO-1, occludin, and claudin-3. Furthermore, disease severity correlates positively with the degree of disruption of tight junctions. In addition, higher expression levels of ZEB1, IL-17A, and IFN-γ were observed in the ACP group compared to controls. Overexpression of ZEB1 in hNEpCs led to impairments in the levels of ZO-1, occludin, and claudin-3, while silencing of ZEB1 expression was found to enhance the barrier function of epithelial cells. Finally, IL-17 stimulation of hNECs impaired the expression of TJs-associated molecules (ZO-1, occludin, and claudin-3), which was effectively reversed by the IL-17A + si-ZEB1 group.

Conclusions

The tight junctions in ACP were extremely damaged and were correlated with the severity of the disease. ZEB1 was involved in the pathogenesis of ACP mediated by IL-17A through regulating tight junctions.

Upper and lower airway interactions in children

PURPOSE OF REVIEW

The aim of the present review was to highlight the interactions between rhinitis, rhinosinusitis and asthma in children and to discuss the most relevant scientific progresses in the pathophysiology and treatment of these combined conditions.

RECENT FINDINGS

Advances in understanding the mechanisms underlying the relationship between upper and lower airways have provided valuable insights into the role of eosinophils in the pathophysiology of inflammatory events and have further delineated the concept of united airway disease. Studies addressed to evaluate the burden of sinonasal system on asthma outcomes showed a parallel severity of upper and lower airway diseases. Histopathology of sinonasal tissue in patients with chronic rhinosinusitis is different in adults and children. Targeted administration of biological agents represents an effective treatment in patients with severe uncontrolled asthma, but specific trials are awaited in children with chronic sinonasal disease.

SUMMARY

Allergic rhinitis and rhinosinusitis are important comorbidities in patients with asthma. Improved knowledge of pathogenic mechanisms of inflammation and remodelling in the sinonasal system and the lung has led to new therapeutic approaches in patients with united airway disease and opened interesting perspectives for personalized drug therapies.

Single-cell RNA sequencing reveals the epithelial cell, fibroblast, and key gene alterations in chronic rhinosinusitis with nasal polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory disease of the nasal mucosa, and epithelial-mesenchymal transition (EMT) is thought to be an essential process in the pathogenesis of CRSwNP. However, the mechanisms of epithelial and fibroblastic changes at the single-cell level are unclear. In this study, we investigated the epithelial cell, fibroblast, and key gene alterations in the development of CRSwNP. We revealed major cell types involved in CRSwNP and nasal mucosal inflammation formation, then mapped epithelial and fibroblast subpopulations. We showed that the apical and glandular epithelial cells and the ADGRB3+ and POSTN+ fibroblasts were the key cell subtypes in the progression of CRSwNP. Pseudotime and cell cycle analysis identified dynamic changes between epithelial cells and fibroblasts during its development. WFDC2 and CCL26 were identified as the key marker genes involved in the development of CRSwNP and were validated by IHC staining, which may provide a potential novel target for future CRSwNP therapy. ScRNA-seq data provided insights into the cellular landscape and the relationship between epithelial cells and fibroblasts in the progression of CRSwNP. WFDC2 and CCL26 were identified as the key genes involved in the development of CRSwNP and may be the potential markers for gene therapy.

Modulation of the Immune Response to Allergies Using Alternative Functional Foods

Modulation of the allergic immune response through alternative therapies is a field of study that aims to address allergic reactions differently from traditional approaches. These therapies encompass the utilization of natural functional foods, which have been observed to exert an influence on the immune response, thus mitigating the severity of allergies. Indeed, some studies suggest that the incorporation of these nutraceuticals can regulate immune function, leading to a reduction in histamine release and subsequent alleviation of allergic symptoms. Moreover, certain herbs and dietary supplements, such as curcumin, are believed to possess anti-inflammatory properties, which may serve to moderate allergic responses. Although the results remain somewhat mixed and require further research, these alternative therapies exhibit the potential to impact the allergic immune response, thereby providing complementary options to conventional treatments. Therefore, in this review, we aim to provide an updated account of functional foods capable of modulating the immune response to allergies. In that sense, the review delves into functional foods sourced from plants (phytochemicals), animals, and marine algae. Emphasis is placed on their potential application in the treatment of allergic disorders. It also provides an overview of how these foods can be effectively utilized as functional foods. Additionally, it explores the molecular mechanisms and scientific validity of various bioactive natural compounds in the management of allergies.

Cigarette smoke aggravates asthma via altering airways inflammation phenotypes and remodelling

INTRODUCTION

Many asthmatic patients are exposed to cigarette smoke actively or passively, which contributes to asthma exacerbation and poor control. This study is to explore the effects of cigarette smoke on pathological changes in murine surrogate of asthma.

METHODS

C57BL/6 mice were sensitised and challenged with ovalbumin (OVA) to establish a surrogate of asthma and then administered with cigarette smoke extract (CSE). Airways hyperresponsiveness (AHR) was measured using the Flexivent system. Histological staining (haematoxylin-eosin [HE], periodic acid Schiff [PAS], Congo red and Masson's trichrome) was employed to measure pathological changes in sections of lung tissue of experimental mice. Enzyme-linked immunosorbent assay (ELISA) was used to measure the concentrations of total and OVA-specific IgE, cytokines and chemokines (eotaxin-1, IL-13, IL-1β, TNF-α, IL-17A, IL-33) in the lung tissue homogenates. Immunoreactivity for vWF and α-SMA in lung tissue sections was detected by immunohistochemistry.

RESULTS

Exposure of the animals to CSE significantly reduced OVA-induced AHR, the number of eosinophils in bronchoalveolar lavage fluid (BALF) and eosinophils infiltrating into the lung tissue, as well as concentrations of some cytokines in lung homogenate. In contrast, it significantly enhanced the number of macrophages and M2 in BALF, as well as collagen deposition, smooth muscle thickness and alveolar destruction in lung tissue.

CONCLUSION

CSE inhibits OVA-induced AHR, changes inflammation 'phenotypes', while accelerates some aspects of airways remodelling, which might contribute to worse symptoms and be refractory to anti-inflammation therapies for asthmatics.

Loke zupa decoction attenuates bronchial EMT-mediated airway remodelling in chronic asthma through the PI3K-Akt/HIF-1α signaling pathway

CONTEXT

Loke zupa decoction (Lok) is a well-established classic Chinese folk remedy for asthma.

OBJECTIVE

We sought to investigate the effect and mechanism of Lok on asthma airway remodelling and provide novel insights for the prevention and treatment of asthma.

MATERIALS AND METHODS

For in vitro experiments, BEAS-2B cells were assigned into six groups: Control, TGF-β1 (10 μM), TGF-β1 + Lok-20, TGF-β1 + Lok-40, TGF-β1 + Lok-80 μg/mL and TGF-β1 + SB431542 (5 μM). CCK8 and wound healing assays were performed. For in vivo experiments, 60 female BALB/c mice were randomly divided into 5 groups: Control, model, Lok-4.55, Lok-9.1, and DEX group. Lok was administrated by gavage during the challenge stage for 8 consecutive weeks (4.55 and 9.1 g/kg/day). We investigated airway inflammation and airway remodelling in the lungs and verified the activation status of EMT-related markers and the PI3K-Akt/HIF-1α signalling pathway.

RESULTS

In vitro, Lok efficiently inhibited TGF-β1-induced BEAS-2B cell proliferation ability (cell viability 165% vs. 105%) and migration (migration areas 85% vs. 35%) without affecting their normal growth (IC50 274.2 µg/mL at 48 h). In vivo, Lok effectively protected mice from asthma, as evidenced by decreased histological damage and level of cytokines in BALF (IL-4, IL-13 and TGF-β1) by 17%-77%. Mechanistic research revealed that Lok reduced the levels of EMT-related molecules and significantly downregulated the PI3K-Akt/HIF-1α signalling pathway.

DISCUSSION AND CONCLUSIONS

Our findings provide novel insights into the protective effect of Lok on asthma and the underlying mechanisms, providing a theoretical basis and potential treatment possibilities for this patient population.

Chemerin and IL-17 are potential predictors and Chemerin silencing alleviates inflammatory response and bone remodeling in chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is an inflammatory disease of paranasal sinuses. This study is formulated to explore the roles of pro-inflammatory factors Chemerin and interleukin-17 (IL-17) in CRS. Patients suffering from CRS without/with nasal polyps (CRSsNP/CRSwNP), along with volunteers, were recruited. CRS rabbit models were constructed by Staphylococcus aureus infection and rabbits were injected with lentiviral vectors of short hairpin RNA-targeting Chemerin (shChemerin), followed by micro-computed tomography (CT) scan. Levels of Chemerin and IL-17 were determined, and histopathological lesions were observed in subjects and CRS rabbits. Correlations between Chemerin/IL-17 level and Lund-Mackay/Lund-Kennedy scores of subjects and the predictive value of Chemerin or IL-17 for CRS were analyzed. In CRS patients and rabbits, inflammatory degrees and the level of Chemerin/IL-17 were increased in pathological tissues or plasma, while Chemerin silencing alleviated CRS symptoms of CRS rabbits. Chemerin and IL-17 were mainly located in the immune cells of pathological tissues and presented the positive correlation with Lund-Mackay/Lund-Kennedy score of CRS patients. Also, they showed high predictive value for CRS. Micro-CT scan uncovered that CRS rabbits had increased bone remodeling, which was alleviated by Chemerin silencing. Collectively, Chemerin and IL-17 are potential predictors and Chemerin silencing alleviates inflammatory response and bone remodeling in chronic rhinosinusitis.

Association of serum CD14 level and functional polymorphism C-159T in the promoter region of CD14 gene with allergic rhinitis

Allergic rhinitis (AR) is an inflammatory disease of the upper respiratory tract affecting a significant number of the world's population. It occurs as an IgE-mediated immune response of the nasal mucosa to inhaled allergens. The human Cluster of Differentiation 14 (CD14) is a glycosyl-phosphatidylinositol-anchored molecule expressed on the surface of monocytes and macrophages and functions as a receptor to lipopolysaccharides and inhaled endotoxins that may stimulate interleukins production by antigen-presenting cells. Consequently, CD14 plays a substantial role in allergic diseases and may become one of their etiological causes. This study aimed to determine the association between C-159T polymorphism in the CD14 gene promoter region and serum CD14 levels and the risk of Allergic rhinitis Egyptian patients and to test the validity of serum CD14 level measurement in predicting AR. This case-control study included 45 patients with AR referred to Allergy and Immunology Unit, Zagazig University Hospital, Zagazig, Egypt, and 45 healthy subjects as controls. Serum CD14 levels were measured by ELISA. The polymerase chain reaction-restriction fragment length polymorphism technique was used to detect C-159T gene polymorphism in the CD14 promoter region. There was a significant association between CD14 serum levels and AR incidence (P < 0.001), with patients having higher serum CD14 levels than controls. In addition, a significant association (P < 0.001) was detected between serum CD14 levels and the severity of AR, as well as elevated serum CD14 levels in severe and the most severe cases. On the molecular level, there was a statistically significant relationship between patients and the control group regarding the CD14 genotype (P < 0.001), where CT and TT genotypes and T allele were primarily associated with the cases group, indicating that the risk of AR was significantly associated with the inheritance of the TT genotype. Additionally, a statistically significant association was found between the severity of AR and CD14 genotype (P < 0.001), where TT genotypes were mainly associated with severe and the most severe cases. In the studied groups, there was a statistically significant difference (P < 0.05) between the CD14 genotype and serum CD14 levels, with TT genotypes being associated with higher CD14 levels. The results obtained in this study revealed that serum CD14 level is a potential biomarker for the diagnosis of AR and, at the genetic level, a potential predictor of disease.

IL18R1-Related Molecules as Biomarkers for Asthma Severity and Prognostic Markers for Idiopathic Pulmonary Fibrosis

To determine the role of inflammation-related proteins in predicting asthma severity and outcome, 92 inflammation-related proteins were measured in the asthmatic serum using Olink analysis. Different bioinformatics algorithms were developed to cross analyze with the single-cell or transcriptome data sets from the Gene Expression Omnibus database to explore the role of IL18R1 and related genes in asthma and idiopathic pulmonary fibrosis (IPF). Olink identified 52 differentially expressed proteins in asthma. They were strongly linked to the cytokine-cytokine receptor interaction, TNF, and NF-κB signaling pathway. Seven proteins were found in both single-cell RNA and Olink analyses. Among them, IL18R1 was predominantly expressed in mast cells, and the results suggested enhanced communication between mast cells and CD 8+ T cells. IL18R1 was upregulated in serum and induced sputum and bronchoalveolar lavage fluid of patients with uncontrolled or severe asthma. IL18R1 was positively correlated with TNFSF1 and OSM and S100A12. The diagnostic efficacy of these serum IL18R1-related molecules for asthma ranged from 0.839 to 0.921. Moreover, high levels of IL18R1, TNFSF1, OSM, and S100A12 were significantly associated with shorter survival times and worse lung function. IL18R1-related molecules may serve as biomarkers for monitoring uncontrolled or severe asthma and as prognostic markers for IPF.

Eosinophils and tissue remodeling: Relevance to airway disease

The ability of human tissue to reorganize and restore its existing structure underlies tissue homeostasis in the healthy airways, but in disease can persist without normal resolution, leading to an altered airway structure. Eosinophils play a cardinal role in airway remodeling both in health and disease, driving epithelial homeostasis and extracellular matrix turnover. Physiological consequences associated with eosinophil-driven remodeling include impaired lung function and reduced bronchodilator reversibility in asthma, and obstructed airflow in chronic rhinosinusitis with nasal polyps. Given the contribution of airway remodeling to the development and persistence of symptoms in airways disease, targeting remodeling is an important therapeutic consideration. Indeed, there is early evidence that eosinophil attenuation may reduce remodeling and disease progression in asthma. This review provides an overview of tissue remodeling in both health and airway disease with a particular focus on eosinophilic asthma and chronic rhinosinusitis with nasal polyps, as well as the role of eosinophils in these processes and the implications for therapeutic interventions. Areas for future research are also noted, to help improve our understanding of the homeostatic and pathological roles of eosinophils in tissue remodeling, which should aid the development of targeted and effective treatments for eosinophilic diseases of the airways.

The interplay of inflammation and remodeling in the pathogenesis of chronic rhinosinusitis: current understanding and future directions

Chronic rhinosinusitis (CRS), a common clinical condition characterized by persistent mucosal inflammation and tissue remodeling, has a complex pathogenesis that is intricately linked to innate and adaptive immunity. A number of studies have demonstrated that a variety of immune cells and cytokines that play a vital role in mediating inflammation in CRS are also involved in remodeling of the nasal mucosa and the cells as well as different cytokines involved in remodeling in CRS are also able to exert some influence on inflammation, even though the exact relationship between inflammation and remodeling in CRS has not yet been fully elucidated. In this review, the potential role of immune cells and cytokines in regulating inflammation and remodeling of CRS mucosa has been described, starting with the immune cells and cytokines that act together in inflammation and remodeling. The goal is to aid researchers in understanding intimate connection between inflammation and remodeling of CRS and to offer novel ideas for future research.

Risk Factors for Acute Rhinosinusitis in Childhood Asthma

INTRODUCTION

Specific pathogen infections associated with acute rhinosinusitis (ARS) in infants are risk factors for allergic asthma in adolescents. However, the risk factors for ARS onset remain largely unknown in asthmatic children. In this study, we aim to investigate the risk factors for ARS in childhood asthma.

METHODS

This study retrospectively compared and analyzed the clinical characteristics of asthmatic children with (n = 194) or without ARS (n = 799). Univariate regression analyses were performed to identify ARS-associated risk factors in asthmatic children, and subsequent multivariate backward stepwise logistic regression analyses were performed to identify independent risk factors.

RESULTS

The onset age, values of blood eosinophils (EOS) (%), and total IgE were significantly lower in patients with ARS than in those without ARS. Moreover, the proportions of patients allergic to Dermatophagoides pteronyssinus (d1) and Dermatophagoides farinae (d2) were significantly smaller in children with ARS (all p values <0.05). Univariate analyses showed that an older onset age, a higher body mass index, a higher value of blood EOS (%) were protective factors, while a higher value of blood lymphocytes (%) and a higher degree of sensitization to d1 and d2 were risk factors for ARS. Further backward stepwise multivariate logistic regression analyses confirmed that a younger onset age and allergic sensitization to d1 were independent risk factors for ARS in childhood asthma.

CONCLUSION

Younger onset age and allergic sensitization to d1 are risk factors for the onset of ARS in childhood asthma, so allergen intervention should be performed as early as possible in asthmatic children.

The Unified Airway Hypothesis: Evidence From Specific Intervention With Anti-IL-5 Biologic Therapy

The unified airway hypothesis proposes that upper and lower airway diseases reflect a single pathological process manifesting in different locations within the airway. Functional, epidemiological, and pathological evidence has supported this well-established hypothesis for some time. However, literature on the pathobiologic roles/therapeutic targeting of eosinophils and IL-5 in upper and lower airway diseases (including asthma, chronic rhinosinusitis with nasal polyps [CRSwNP], and nonsteroidal anti-inflammatory drug-exacerbated respiratory disease) has recently emerged. This narrative review revisits the unified airway hypothesis by searching the scientific literature for recent learnings and clinical trial/real-world data that provide a novel perspective on its relevance for clinicians. According to the available literature, eosinophils and IL-5 have important pathophysiological roles in both the upper and lower airways, although the impact of eosinophils and IL-5 may vary in asthma and CRSwNP. Some differential effects of anti-IL-5 and anti-IL-5-receptor therapies in CRSwNP have been observed, requiring further investigation. However, pharmaceutical targeting of eosinophils and IL-5 in patients with upper, lower, and comorbid upper and lower airway inflammation has led to clinical benefit, supporting the hypothesis that these are linked conditions manifesting in different locations. Consideration of this approach may improve patient care and aid clinical decision making.

Higher Prevalence and Severity of Eosinophilic Otitis Media in Patients with Asthma-COPD Overlap Compared with Asthma Alone

INTRODUCTION

Eosinophilic otitis media (EOM) is well-known to frequently co-exist with adult-onset asthma. Both diseases are similar type 2 inflammation and are considered to have a "one airway, one disease" relationship. Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO), characterized by airway obstruction caused by airway wall thickening (AWT), is a severe condition with a higher incidence of mortality compared to asthma alone or COPD alone. Based on the "one airway, one disease" concept, we hypothesized that the inflammatory pathophysiology of EOM differs depending on its comorbidity with ACO or with asthma alone.

METHODS

A total of 77 chronic rhinosinusitis (CRS) patients with asthma were enrolled in this study. The subjects were divided into 2 groups: a group with comorbid asthma alone (asthma group; 46 patients), and a group with comorbid ACO (ACO group; 31 patients). The 2 groups were compared and assessed with regard to various factors, including the patients' clinical characteristics, prevalence rate of EOM, EOM severity, EOMs relationships with smoking and AWT, and the eosinophil and neutrophil cell counts in the middle ear effusion (MEE).

RESULTS

The ACO group included significantly more males (p < 0.05), was significantly older (p < 0.05), and showed significantly lower lung function values (FEV1 [L], FEV1 [%pred]) (p < 0.01) compared with the asthma group. The ACO group also had a significant history of smoking as shown by the Brinkman index (p < 0.01) and greater AWT as assessed by high-resolution computed tomography (p < 0.05). The EOM prevalence rate was significantly higher in the ACO group (p < 0.05), especially with increased ACO severity (p < 0.05). The EOM severity was also significantly higher in the ACO group (p < 0.05) and also correlated with the ACO severity (p < 0.05). The pretreatment ear clinical characteristics score and the average air conduction hearing level were significantly higher in the ACO group (p < 0.05). The eosinophil percentage in the MEE/otorrhea was significantly lower in the ACO group (25.3%) than in the asthma group (54.7%) (p < 0.05). Conversely, the neutrophil percentage was significantly higher in the ACO group (75.7% vs. 41.9%) (p < 0.05).

CONCLUSIONS

Our findings suggest that, in CRS patients with asthma, comorbidity with ACO may be a clinical factor leading to increased EOM prevalence and severity, as well as a higher neutrophil infiltration percentage in the middle ear. Cessation of smoking and early therapeutic intervention for ACO may mitigate progression of bronchial remodeling (i.e., reduce AWT) and help reduce the prevalence and severity of EOM.

Proline is increased in allergic asthma and promotes airway remodeling

Proline and its synthesis enzyme pyrroline-5-carboxylate reductase 1 (PYCR1) are implicated in epithelial-mesenchymal transition (EMT), yet how proline and PYCR1 function in allergic asthmatic airway remodeling via EMT has not yet been addressed to our knowledge. In the present study, increased levels of plasma proline and PYCR1 were observed in patients with asthma. Similarly, proline and PYCR1 in lung tissues were high in a murine allergic asthma model induced by house dust mites (HDMs). Pycr1 knockout decreased proline in lung tissues, with reduced airway remodeling and EMT. Mechanistically, loss of Pycr1 restrained HDM-induced EMT by modulating mitochondrial fission, metabolic reprogramming, and the AKT/mTORC1 and WNT3a/β-catenin signaling pathways in airway epithelial cells. Therapeutic inhibition of PYCR1 in wild-type mice disrupted HDM-induced airway inflammation and remodeling. Deprivation of exogenous proline relieved HDM-induced airway remodeling to some extent. Collectively, this study illuminates that proline and PYCR1 involved with airway remodeling in allergic asthma could be viable targets for asthma treatment.

Mahuang Fuzi Xixin decoction ameliorates allergic rhinitis and repairs the airway epithelial barrier by modulating the lung microbiota dysbiosis

Background

Allergic rhinitis (AR) is a common disorder, that burdens general well-being. Although the lung is connected to the upper respiratory tract, which is rich in microorganisms, no studies have reported the relationship between lung microbiota and AR. Mahuang Fuzi Xixin decoction (MFXD) is a traditional Chinese medicine (TCM) formula that is widely used to treat AR in the clinic but its underlying mechanism remains unclear.

Hypothesis

We hypothesized that lung microbiota is associated with the pathogenesis of AR, and MFXD can improve AR by regulating microbiota dysbiosis.

Methods

The ovalbumin-induced mouse AR model was used to evaluate the therapeutic effect of MFXD on AR. Then 16S rDNA amplicon sequencing, untargeted metabolomics, and other molecular biology technology were used to clarify the effects of MFXD on lung microbes dysbiosis and AR progression. Further, the human nasal epithelial cell line (HNEpCs) was used to evaluate the protective effect of MFXD on epithelial barrier damage caused by specific pathogens.

Results

MFXD decreased plasma histamine and IgE levels, ameliorated pathological damage, and diminished the expression of tight junction proteins (ZO-1 and occludin) in lung and nasal tissues. MFXD altered AR-induced microbiota dysbiosis in the lungs and also plasma metabolites. Oral administration of MFXD altered microbiota dysbiosis in lung and AR-associated metabolic disorders. The dominant bacteria in the lungs of AR mice damaged the airway barrier, and MFXD reversed this change.

Conclusion

This study revealed the correlation between the lung microbiota and AR in the mice model. We confirmed that lung microbiota plays a vital role in AR and that MFXD reduced damage to the epithelial barrier of the lungs and nasal mucosa by regulating lung microbiota and plasma metabolism imbalances. Our research provides a reference for the effect of lung microbiota on AR and provides a new idea for the treatment of AR.

Exploring Associations Between Short-Term Air Pollution and Daily Outpatient Visits for Allergic Rhinitis

Purpose

Many studies have reported that exposure to air pollution increases the likelihood of acquiring allergic rhinitis (AR). This study investigated associations between short-term air pollution exposure and AR outpatient visits.

Patients and Methods

The Department of Otorhinolaryngology, Affiliated Hospital of Hangzhou Normal University provided AR outpatient data from January 1, 2019 to December 31, 2021. Daily air quality information for that period was gathered from the Hangzhou Air Quality Inspection Station. We used the Poisson's generalized additive model (GAM) to investigate relationships between daily outpatient AR visits and air pollution, and investigated lag-exposure relationships across days. Subgroup analyses were performed by age (adult (>18 years) and non-adult (<18 years)) and sex (male and female).

Results

We recorded 20,653 instances of AR during the study period. Each 10 g/m3 increase in fine particulate matter (PM10 and PM2.5) and carbon monoxide (CO) concentrations was associated with significant increases in AR outpatient Visits. The relative risks (RR) were: 1.007 (95% confidence interval (CI): 1.001-1.013), 1.026 (95% CI: 1.008-1.413), and 1.019 (95% CI: 1.008-1.047). AR visits were more likely due to elevated PM2.5, PM10, and CO levels. Additionally, children were more affected than adults.

Conclusion

To better understand the possible effects of air pollution on AR, short-term exposure to ambient air pollution (PM2.5, PM10, and CO) may be linked to increased daily outpatient AR visits.

Clinical and immunologic implication of neo-osteogenesis in chronic rhinosinusitis

INTRODUCTION

Chronic rhinosinusitis (CRS) is a multifactorial disease characterized by long-term inflammation of the nasal and sinus passages. Neo-osteogenesis which is a major finding of recalcitrant CRS is clinically related to the disease severity and surgical outcomes of CRS.

AREAS COVERED

The immunological and molecular mechanisms underlying neo-osteogenesis of CRS remain unclear, and many recent studies have suggested the importance of inflammatory mediators secreted by immune cells. This paper provides a broader understanding of neo-osteogenesis in CRS by reviewing recent updates and evidence of the association between CRS pathophysiology and neo-osteogenesis.

EXPERT OPINION

Crosstalk between the bone and mucosa eventually results in refractory CRS. In addition, both eosinophilic and non-eosinophilic CRS cytokines can play a role in neo-osteogenesis and trigger an enhanced CRS-associated immune response. The significance of predicting neo-osteogenesis in advance or during postoperative care could be essential for effectively managing refractory CRS and enhancing the prognosis of CRS patients.

Microenvironment modulation by key regulators of RNA N6-methyladenosine modification in respiratory allergic diseases

BACKGROUND

RNA N6-methyladenosine (m6A) regulators are considered post-transcriptional regulators that affect several biological functions, and their role in immunity, in particular, is emerging. However, the role of m6A regulators in respiratory allergic diseases remains unclear. Therefore, we aimed to investigate the role of key m6A regulators in mediating respiratory allergic diseases and immune microenvironment infiltration characteristics.

METHODS

We downloaded gene expression profiles of respiratory allergies from the Gene Expression Omnibus (GEO) database and we performed hierarchical clustering, difference analysis, and construction of predictive models to identify hub m6A regulators that affect respiratory allergies. Next, we investigate the underlying biological mechanisms of key m6A regulators by performing PPI network analysis, functional enrichment analysis, and immune microenvironment infiltration analysis. In addition, we performed a drug sensitivity analysis on the key m6A regulator, hoping to be able to provide some implications for clinical medication.

RESULTS

In this study, we identified four hub m6A regulators that affect the respiratory allergy and investigated the underlying biological mechanisms. In addition, studies on the characteristics of immune microenvironment infiltration revealed that the expression of METTL14, METTL16, and RBM15B correlated with the infiltration of the mast and Th2 cells in respiratory allergy, and METTL16 expression was found to be significantly negatively correlated with macrophages for the first time (R = -0.53, P < 0.01). Finally, a key m6A regulator, METTL14, was screened by combining multiple algorithms. In addition, by performing a drug sensitivity analysis on METTL14, we hypothesized that it may play an important role in the improvement of allergic symptoms in the upper and lower airways with topical nasal glucocorticoids.

CONCLUSIONS

Our findings suggest that m6A regulators, particularly METTL14, play a crucial role in the development of respiratory allergic diseases and the infiltration of immune cells. These results may provide insight into the mechanism of action of methylprednisolone in treating respiratory allergic diseases.

The Mechanism of Action and Clinical Efficacy of Low-Dose Long-Term Macrolide Therapy in Chronic Rhinosinusitis

Various chronic inflammatory airway diseases can be treated with low-dose, long-term (LDLT) macrolide therapy. LDLT macrolides can be one of the therapeutic options for chronic rhinosinusitis (CRS) due to their immunomodulatory and anti-inflammatory actions. Currently, various immunomodulatory mechanisms of the LDLT macrolide treatment have been reported, as well as their antimicrobial properties. Several mechanisms have already been identified in CRS, including reduced cytokines such as interleukin (IL)-8, IL-6, IL-1β, tumor necrosis factor-α, transforming growth factor-β, inhibition of neutrophil recruitment, decreased mucus secretion, and increased mucociliary transport. Although some evidence of effectiveness for CRS has been published, the efficacy of this therapy has been inconsistent across clinical studies. LDLT macrolides are generally believed to act on the non-type 2 inflammatory endotype of CRS. However, the effectiveness of LDLT macrolide treatment in CRS is still controversial. Here, we reviewed the immunological mechanisms related to CRS in LDLT macrolide therapy and the treatment effects according to the clinical situation of CRS.

Rethinking the relationships between chronic rhinosinusitis and asthma severity

BACKGROUND

Previous authors have endorsed the need for prospective studies on the effect of treatment of chronic rhinosinusitis on asthma outcomes. Although common pathophysiology for asthma and chronic rhinosinusitis (CRS) has been suggested with the unified airway theory, there is limited data to support the claim and our study does not support the theory.

METHODS

This case-control study involved adult patients with a primary diagnosis of asthma in 2019 who were identified from the electronic medical records and divided into those with and without an associated CRS diagnosis. For each asthma encounter, the asthma severity classification, oral corticosteroid (OCS) use and oxygen saturation scores were tabulated and compared between asthma patients with CRS versus control patients after 1:1 matching on age and sex. We determined the association between asthma and chronic rhinosinusitis when evaluating proxies for disease severity: oral corticosteroid use, average oxygen saturation and minimum oxygen saturation. We identified 1321 clinical encounters for asthma associated with CRS and 1321 control encounters for asthma without CRS.

RESULTS

OCS prescription rates at the asthma encounter were not statistically different between the groups (15.3 % and 14.6 %, respectively; p = 0.623). Asthma severity classification was higher in those with CRS versus those without (38.9 % and 25.7 % classified as severe, respectively; p < 0.001). We identified 637 asthma with CRS and 637 matched control patients. There was no significant difference in mean recorded O2 saturations between asthma patients with CRS versus control patients (mean O2 saturations, 97.2 % and 97.3 %, respectively; p = 0.816) nor in minimum oxygen saturation (96.8 % and 97.0 %, respectively; p = 0.115).

CONCLUSION

Among patients with a primary diagnosis of asthma an increasing severity of asthma classification was significantly associated with an associated diagnosis of CRS. In contradistinction, the presence of CRS comorbidity in asthma patients was not associated with increased OCS use for asthma. Similarly, average oxygen saturation and minimum oxygen saturation did not seem differ according to CRS comorbidity. Our study does not support the unified airway theory that suggests a causative relationship between the upper and lower airway.

Ablation of CD226 on CD4+ T cells modulates asthma progress associated with altered IL-10 response and gut microbiota

To investigate the role of the costimulatory molecule CD226 in asthma pathogenesis, we produced a CD4⁺ T-cell-specific CD226 knockout mice model (Cd226^ΔCD4) and induced airway allergic inflammation by administering ovalbumin (OVA). Our results revealed alleviated lung inflammation, decreased levels of OVA-specific IgE, and increased levels of IL-10 in the serum of Cd226^ΔCD4 mice (P < 0.05). Moreover, IL-10 levels in CD4⁺ T cells were significantly elevated in the mediastinal lymph node, spleen, and Peyer's patches in the Cd226^ΔCD4 mice compared with those in controls (P < 0.05 to P < 0.01). Notably, there was a significantly higher IL-10 mRNA levels in the large intestine of the mice (P < 0.05). The protective effect of CD226 deficiency is also associated with the accumulation of gut TCRγδ⁺ intraepithelial lymphocytes and reversion of the gut microbiome dysbiosis. The Bacteroidetes-to-Firmicutes ratio and the abundance of Akkermansia increased in the absence of CD226 after OVA treatment. Our data reveal the synchronous changes in the lung and intestine in OVA-treated CD226-knockout mice, supporting the gut-lung axis concept and providing evidence for novel therapeutic approaches for asthma.

Early-life cadmium exposure elevates susceptibility to allergic asthma in ovalbumin-sensitized and challenged mice

Increasing evidence have demonstrated that early-life exposure to environmental toxicants elevates risk of allergic asthma. Cadmium (Cd) is widely present in the environment. The purposes of this study were to evaluate the impact of early-life Cd exposure on susceptibility to ovalbumin (OVA)-evoked allergic asthma. Newly weaned mice were subjected to a low concentration of CdCl₂ (1 mg/L) by drinking water for 5 consecutive weeks. Penh value, an index of airway obstruction, was increased in OVA-stimulated and challenged pups. Abundant inflammatory cells were observed in the lung of OVA-exposed pups. Goblet cell hyperplasia and mucus secretion were shown in the airway of OVA-stimulated and challenged pups. Early-life Cd exposure exacerbated OVA-evoked airway hyperreactivity, Goblet cell hyperplasia and mucus secretion. The in vitro experiments showed that mucoprotein gene MUC5AC mRNA was upregulated in Cd-exposed bronchial epithelial cells. Mechanistically, endoplasmic reticulum (ER) stress-related molecules GRP78, p-eIF2α, CHOP, p-IRE1α and spliced XBP-1 (sXBP-1) were elevated in Cd-subjected bronchial epithelial cells. The blockade of ER stress, using chemical inhibitor 4-PBA or sXBP-1 siRNA interference, attenuated Cd-induced MUC5AC upregulation in bronchial epithelial cells. These results indicate that early-life Cd exposure aggravates OVA-induced allergic asthma partially through inducing ER stress in bronchial epithelial cells.

Real-Life Effectiveness of Benralizumab, Mepolizumab and Omalizumab in Severe Allergic Asthma Associated with Nasal Polyps

Biological therapies are available for the treatment of the severe allergic asthma (SAA) with blood eosinophil count ≥ 0.3 × 10⁹/L. Several of them also showed benefits on nasal polyps (NP), one of the most frequent comorbidities of the severe asthma, but comparative studies on their effectiveness in the association SAA-NP are currently lacking. The aim of this study is to compare the effectiveness of benralizumab, mepolizumab and omalizumab in patients with SAA-NP in real-life settings. A retrospective, observational, multicenter real-life study was realized including patients with SAA-NP treated by benralizumab, mepolizumab or omalizumab for 6 months. We analysed the nasal and respiratory symptoms, the number of asthma attacks and salbutamol use/week, acute sinusitis and severe exacerbation rates, the asthma control score, the lung function parameters, the NP endoscopic score, the sinus imaging and the blood eosinophil count 6 months before and after treatment. Seventy-two patients with SAA-NP were included: 16 treated by benralizumab, 21 by mepolizumab and 35 by omalizumab. After 6 months of treatment, almost all studied parameters were improved (except sinus imaging) with a greater effect of omalizumab on the nasal pruritus (p = 0.001) and more benefits of benralizumab on exacerbations rate, asthma attacks per week and lung function (all p < 0.05). Benralizumab and mepolizumab were more effective to improve the NP endoscopic score and the blood eosinophil count (both p < 0.001). All three biological therapies showed effectiveness by improving asthma and nasal outcomes in patients with SAA-NP. Several differences have been found that should be confirmed by larger comparative studies.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Clinical features of asthma with connective tissue diseases

BACKGROUND

The clinical features of asthma with connective tissue diseases (CTDs) are not well-known. This study therefore aimed to investigate the clinical characteristics of asthma with CTDs.

METHODS

We retrospectively examined the records of adults (≥18 years old) with asthma followed up between January 2010 and December 2019. We then compared the clinical features of asthma with and without CTDs.

RESULTS

Among 568 subjects with asthma, 42 subjects (7.4%) had CTDs. The most frequent concomitant CTD was rheumatoid arthritis (n = 23, 54.8%), followed by systemic lupus erythematosus (n = 6, 14.3%). The proportion of women (with vs. without CTDs, 85.7% vs. 56.5%, p < 0.001) and Global Initiative for Asthma step were higher (Step 4 or 5, with vs. without CTDs, 81.0% vs. 62.0%, p = 0.01) in asthma with CTDs, whereas frequency of allergic rhinitis was higher in asthma without CTDs (with vs. without CTDs, 7.1% vs. 26.1%, p = 0.005). Eosinophil ratio (with vs. without CTDs, 2.1% vs. 3.5%, p = 0.009) and total immunoglobulin E level (with vs. without CTDs, 43 IU/mL vs. 237 IU/mL, p = 0.002) were lower in asthma with CTDs. In terms of lung function, percentage predicted forced vital capacity (with vs. without CTDs, 86.7% vs. 99.7%, p = 0.008) and percentage predicted forced expiratory volume in 1 s (%FEV1) (with vs. without CTDs, 77.2% vs. 88.4%, p = 0.02) were all lower in asthma with CTDs. With multivariable analysis, CTDs (odds ratio [OR] 2.8, 95%CI 1.3-6.0; p = 0.008), chronic obstructive pulmonary disease (OR 3.8, 95%CI 2.1-6.7; p < 0.001) and asthma onset at <20 years old (OR 1.8, 95%CI 1.1-3.2; p = 0.03) were associated with low FEV1 (defined as %FEV1 < 80%) in asthma.

CONCLUSIONS

Asthma with CTDs was related to lower lung function and low-T2 inflammation asthma.

Role of Nasal Fibroblasts in Airway Remodeling of Chronic Rhinosinusitis: The Modulating Functions Reexamined

Chronic rhinosinusitis (CRS) is a multifactorial inflammatory disease of the nose and sinuses that affects more than 10% of the adult population worldwide. Currently, CRS is classified into endotypes according to the inflammatory response (Th1, Th2, and Th17) or the distribution of immune cells in the mucosa (eosinophilic and non-eosinophilic). CRS induces mucosal tissue remodeling. Extracellular matrix (ECM) accumulation, fibrin deposition, edema, immune cell infiltration, and angiogenesis are observed in the stromal region. Conversely, epithelial-to-mesenchymal transition (EMT), goblet cell hyperplasia, and increased epithelial permeability, hyperplasia, and metaplasia are found in the epithelium. Fibroblasts synthesize collagen and ECM, which create a structural skeleton of tissue and play an important role in the wound-healing process. This review discusses recent knowledge regarding the modulation of tissue remodeling by nasal fibroblasts in CRS.

Blood Inflammatory-like and Lung Resident-like Eosinophils Affect Migration of Airway Smooth Muscle Cells and Their ECM-Related Proliferation in Asthma

Airway remodeling is a hallmark feature of asthma, and one of its key structural changes is increased airway smooth muscle (ASM) mass and disturbed extracellular matrix (ECM) homeostasis. Eosinophil functions in asthma are broadly defined; however, we lack knowledge about eosinophil subtypes' interaction with lung structural cells and their effect on the airway's local microenvironment. Therefore, we investigated the effect of blood inflammatory-like eosinophils (iEOS-like) and lung resident-like eosinophils (rEOS-like) on ASM cells via impact on their migration and ECM-related proliferation in asthma. A total of 17 non-severe steroid-free allergic asthma (AA), 15 severe eosinophilic asthma (SEA) patients, and 12 healthy control subjects (HS) were involved in this study. Peripheral blood eosinophils were enriched using Ficoll gradient centrifugation and magnetic separation, subtyped by using magnetic separation against CD62L. ASM cell proliferation was assessed by AlamarBlue assay, migration by wound healing assay, and gene expression by qRT-PCR analysis. We found that blood iEOS-like and rEOS-like cells from AA and SEA patients' upregulated genes expression of contractile apparatus proteins, COL1A1, FN, TGF-β1 in ASM cells (p < 0.05), and SEA eosinophil subtypes demonstrated the highest effect on sm-MHC, SM22, and COL1A1 gene expression. Moreover, AA and SEA patients' blood eosinophil subtypes promoted migration of ASM cells and their ECM-related proliferation, compared with HS (p < 0.05) with the higher effect of rEOS-like cells. In conclusion, blood eosinophil subtypes may contribute to airway remodeling by upregulating contractile apparatus and ECM component production in ASM cells, further promoting their migration and ECM-related proliferation, with a stronger effect of rEOS-like cells and in SEA.

Nasal Polyposis and Serum Albumin: Systemic Effects of Local Inflammation

Introduction The genesis of chronic rhinosinusitis is always a topic of debate. A polyp is a pale, edematous tissue emerging mostly from the middle meatus. An epithelial injury caused by continuous inflammation of the nasal mucosa is considered to be a possible cause of the genesis of nasosinusal polyps. Objective To understand the link between serum albumin levels and nasal polyposis. Methods A retrospective study of 180 consecutive patients between January 2016 and January 2020 at our center. We then divided the patients into three age- and gender-matched groups: 60 patients with chronic rhinosinusitis with nasal polyposis, 60 patients with chronic rhinosinusitis without nasal polyposis, and a control group with 60 patients. No patient had a history of any pathology that could alter serum albumin. We then compared the level of serum albumin between the three groups. Results The group of patients with rhinosinusitis and nasal polyposis consisted of 60 patients with a serum albumin value of 4.49 ± 0.29 g/dL, whereas in the control group, the serum albumin value was 4.67 ± 0.2 g/dL. We found a significant difference between the group with nasal polyposis and the other two groups evaluated: chronic rhinosinusitis without nasal polyposis (p<0.001) and the control group (p<0.001). Conclusions Lower levels of serum albumin can be seen in patients with chronic rhinosinusitis with nasal polyposis. Further studies should aim to apply its value since it is a non-expensive marker, to the follow-up of those patients or even to stratify them according to their endotype.

MicroRNA-146a-5p and microRNA-210-3p Correlate with T Regulatory Cells Frequency and Predict Asthma Severity in Egyptian Pediatric Population

Background

Severe bronchial asthma (BA) affects 5-10% of children, which imposes socioeconomic burden. Therefore, it is crucial to identify biomarkers for risk stratification in children with BA. T regulatory cells (Tregs) play a balancing role in allergic response regulation. We aimed to investigate the relationship between Treg, miR-210-3p, and miR-146a-5p in relation to asthma phenotypes in search of novel biomarkers of disease severity.

Methods

This study included 50 children with BA classified into Group 1 (n = 25) children with mild to moderate asthma and Group 2 (n = 25) children with severe asthma. In addition to 26 control subjects. Flow cytometry was used to detect Tregs. Plasma miR-210-3p and miR-146a levels were determined using quantitative real-time PCR. Patients' FEV1 (Forced Expiratory Volume in the first second) was measured.

Results

miR-210-3p level correlated negatively with Treg frequency (r = -0.828, P < 0.001) and FEV1 (r = -0.621, P < 0.001). The level of miR-146a-5p positively correlated positively with Treg% (r = 0.303, P = 0.032). ROC curve analysis revealed that miR-210-3p was the most sensitive biomarker of severity, with the area under curve (AUC) = 0.923, 96% sensitivity, and 60% specificity. According to multivariate analysis, miR-210-3p is an independent risk factor for BA severity [OR =3.119, P = 0.030], while miR-146a-5p is a protective factor [OR =0.811, P = 0.049].

Conclusion

Treg frequency is linked to FEV1, miR-146a-5p and miR-210-3p in childhood BA. Upregulation of miR-210-3p is a sensitive biomarker and an independent risk factor for BA severity in Egyptian children.

Vitamin A-regulated ciliated cells promote airway epithelium repair in an asthma mouse model

BACKGROUND

Asthma is a chronic inflammatory airway disease that causes damage to and exfoliation of the airway epithelium. The continuous damage to the airway epithelium in asthma cannot be repaired quickly and generates irreversible damage, repeated attacks, and aggravation. Vitamin A (VA) has multifarious biological functions that include maintaining membrane stability and integrity of the structure and function of epithelial cells. Our research explored the role of VA in repairing the airway epithelium and provided a novel treatment strategy for asthma.

METHODS

A mouse asthma model was established by house dust mite (HDM) and treated with VA by gavage. Human bronchial epithelial (16HBE) cells were treated with HDM and all-trans retinoic acid (ATRA) in vitro. We analyzed the mRNA and protein expression of characteristic markers, such as acetyl-α-tubulin (Ac-TUB) and FOXJ1 in ciliated cells and MUC5AC in secretory cells, mucus secretion, airway inflammation, the morphology of cilia, and the integrity of the airway epithelium.

RESULTS

Findings showed destruction of airway epithelial integrity, damaged cilia, high mucus secretion, increased MUC5AC expression, and decreased Ac-TUB and FOXJ1 expression in asthmatic mice. The VA intervention reversed the effect on Ac-TUB and FOXJ1 and promoted ciliated cells to repair the damage and maintain airway epithelial integrity. In 16HBE cells, we could confirm that ATRA promoted the expression of Ac-TUB and FOXJ1.

CONCLUSION

These results demonstrated that VA-regulated ciliated cells to repair the damaged airway epithelium caused by asthma and maintain airway epithelial integrity. VA intervention is a potential adjunct to conventional treatment for asthma.

MIR222HG attenuates macrophage M2 polarization and allergic inflammation in allergic rhinitis by targeting the miR146a-5p/TRAF6/NF-κB axis

Although M2 macrophages are involved in the orchestration of type 2 inflammation in allergic diseases, the mechanisms underlying non-coding RNA (ncRNA)-mediated macrophage polarization in allergic rhinitis (AR) have not been systematically understood. Here, we identified long non-coding RNA (lncRNA) MIR222HG as a key regulator of macrophage polarization and revealed its role in AR. Consistent with our bioinformatic analysis of GSE165934 dataset derived from the Gene Expression Omnibus (GEO) database, lncRNA-MIR222HG and murine mir222hg were downregulated in our clinical samples and animal models of AR, respectively. Mir222hg was upregulated in M1 macrophages and downregulated in M2 macrophages. The allergen-ovalbumin facilitated polarization of RAW264.7 cells to the M2 phenotype, accompanied by the downregulation of mir222hg expression in a dose-dependent manner. Mir222hg facilitates macrophage M1 polarization and reverses M2 polarization caused by ovalbumin. Furthermore, mir222hg attenuates macrophage M2 polarization and allergic inflammation in the AR mouse model. Mechanistically, a series of gain- and loss-of-function experiments and rescue experiments were performed to verify the role of mir222hg as a ceRNA sponge that adsorbed miR146a-5p, upregulated Traf6, and activated the IKK/IκB/P65 pathway. Collectively, the data highlight the remarkable role of MIR222HG in the modulation of macrophage polarization and allergic inflammation, as well as its potential role as a novel AR biomarker or therapeutic target.

Causal relationships between potential risk factors and chronic rhinosinusitis: a bidirectional two-sample Mendelian randomization study

PURPOSE

Smoking, alcohol consumption, allergic rhinitis (AR), asthma, and obesity are associated with chronic rhinosinusitis (CRS), albeit the causal relationships between them remain elusive. Therefore, we conducted a bidirectional two-sample Mendelian randomization (MR) study to investigate the bidirectional causal effects between these potential risk factors and CRS.

METHODS

The data for daily cigarette consumption, age of smoking initiation, weekly alcohol consumption, AR, asthma, body mass index (BMI), and CRS were drawn from large sample size genome-wide association studies. Single-nucleotide polymorphisms associated with each exposure were considered instrumental variables in this study. We investigated causal effects by using the inverse-variance weighted (IVW) method with random effects, and weighted median and MR-Egger methods were used for sensitivity analyses. Pleiotropic effects were detected and corrected by the MR pleiotropy residual sum and outlier test and MR-Egger model.

RESULTS

We found the causal effects of daily cigarette consumption (IVW, OR = 1.15, 95% CI 1.00-1.32, p = 0.046), AR (IVW, OR = 4.77, 95% CI 1.61-14.13, p = 0.005), asthma (IVW, OR = 1.45, 95% CI 1.31 - 1.60, p < 0.001), and BMI (IVW, OR = 1.05, 95% CI 1.00-1.09, p = 0.028) on CRS. Furthermore, we found a causal effect of CRS on asthma (IVW OR = 1.08, 95% CI 1.05-1.12, p < 0.001).

CONCLUSIONS

We confirmed the causal effects of daily cigarette consumption, AR, asthma, and BMI on CRS, and the causal effect of CRS on asthma, while no causal relationship between age of smoking initiation, weekly alcohol consumption, and CRS was found. These findings are expected to provide high-quality causal evidence for clinical practice and the pathogenesis of CRS and asthma.

Juvenile arsenic exposure aggravates goblet cell hyperplasia and airway mucus secretion in ovalbumin-sensitized mice

Gestational arsenic (As) exposure has been associated with adverse developmental outcomes. The purpose of this study was to explore the impacts of As exposure in different periods on susceptibility to allergic asthma. In model 1, dams were administered with NaAsO₂ (0.1 or 1 ppm) by drinking water throughout pregnancy and lactation. In model 2, newly weaned pups were exposed to NaAsO₂ (1 ppm) through drinking water. Pups were sensitized and challenged with ovalbumin (OVA). Inflammatory cell infiltration and pulmonary T helper 2 (Th2) cytokine upregulation were shown in OVA-sensitized and challenged pups. Goblet cell hyperplasia and airway mucus secretion were observed in OVA-sensitized and challenged pups. Maternal As exposure throughout pregnancy and lactation did not aggravate inflammatory cell infiltration, airway mucus secretion and pulmonary Th2 cytokine upregulation in OVA-sensitized and challenged pups. Although airway hyperreactivity, inflammatory cell infiltration and Th2 cytokine weren't influenced, OVA-evoked Goblet cell hyperplasia and airway mucus secretion were aggravated in pups who were exposed to NaAsO₂ after weaning. In conclusion, juvenile As exposure increases susceptibility to allergic asthma through aggravating Goblet cell hyperplasia and airway mucus secretion. The impacts of maternal As exposure during pregnancy and lactation on susceptibility to allergic asthma needs to be further evaluated in other animal experiments.

A review of upper airway physiology relevant to the delivery and deposition of inhalation aerosols

Developing effective oral inhaled drug delivery treatment strategies for respiratory diseases necessitates a thorough knowledge of the respiratory system physiology, such as the differences in the airway channel's structure and geometry in health and diseases, their surface properties, and mechanisms that maintain their patency. While respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and asthma and their implications on the lower airways have been the core focus of most of the current research, the role of the upper airway in these diseases is less known, especially in the context of inhaled drug delivery. This is despite the fact that the upper airway is the passageway for inhaled drugs to be delivered to the lower airways, and their replicas are indispensable in current standards, such as the cascade impactor experiments for testing inhaled drug delivery technology. This review provides an overview of upper airway collapsibility and their mechanical properties, the effects of age and gender on upper airway geometry, and surface properties. The review also discusses how COPD and asthma affect the upper airway and the typical inhalation flow characteristics exhibited by the patients with these diseases.

Single-cell profiling identifies mechanisms of inflammatory heterogeneity in chronic rhinosinusitis

The heterogeneous cellular microenvironment of human airway chronic inflammatory diseases, including chronic rhinosinusitis (CRS) and asthma, is still poorly understood. Here, we performed single-cell RNA sequencing (scRNA-seq) on the nasal mucosa of healthy individuals and patients with three subtypes of CRS and identified disease-specific cell subsets and molecules that specifically contribute to the pathogenesis of CRS subtypes. As such, ALOX15+ macrophages contributed to the type 2 immunity-driven pathogenesis of one subtype of CRS, eosinophilic CRS with nasal polyps (eCRSwNP), by secreting chemokines that recruited eosinophils, monocytes and T helper 2 (TH2) cells. An inhibitor of ALOX15 reduced the release of proinflammatory chemokines in human macrophages and inhibited the overactivation of type 2 immunity in a mouse model of eosinophilic rhinosinusitis. Our findings advance the understanding of the heterogeneous immune microenvironment and the pathogenesis of CRS subtypes and identify potential therapeutic approaches for the treatment of CRS and potentially other type 2 immunity-mediated diseases.

Efficacy and Safety of Diethylcarbamazine in Treatment of Allergic Rhinitis: A Double Blind Randomised Controlled Trial

There are many evidences showing diethylcarbamazine as a potential drug for the treatment of allergic rhinitis. This study evaluated the effectiveness of diethylcarbamazine in the treatment of allergic rhinitis and compared it with montelukast and levocetirizine. This parallel double-blind randomized clinical trial was done in allergic rhinitis patients. Seven hundred and twelve participants who met the inclusion criteria and provided informed written consent were randomized and divided into 2 equal groups. Diethylcarbamazine 300 mg/day orally in divided doses was given to group A, and montelukast 10 mg and levocetirizine 5 mg/day orally at night for 21 days was given to group B. Primary outcomes were the change in symptoms, absolute eosinophil count, serum total IgE, phadiatop and response in skin prick from baseline to 21 days and 3 months after treatment. Secondary outcome was to compare it with montelukast and levocetirizine. The mean (SD) age of the patients was 33 (10.6) years, with 374 (52.5%) males and 338 (47.5%) females. There was statistically significant improvement in all the parameters in both groups. Improvement was better with diethylcarbamazine compared to montelukast and levocetirizine and the effects were sustained for 3 months in diethylcarbamazine group. The findings suggest that diethylcarbamazine is effective in the treatment of allergic rhinitis. It gives better control and is cost-effective than montelukast and levocetirizine. Trial Registration: https://www.ctri.nic.in Identifier: CTRI/2020/03/024145 registered on 20-03-2020.

Pyroptosis and respiratory diseases: A review of current knowledge

Pyroptosis is a relatively newly discovered programmed cell death accompanied by an inflammatory response. In the classical view, pyroptosis is mediated by caspases-1,-4,-5,-11 and executed by GSDMD, however, recently it was demonstrated that caspase-3 and-8 also participate in the process of pyroptosis, by cleaving GSDMD/E and GSDMD respectively. Different from autophagy and apoptosis, many pores are formed on the cell membrane during pyroptosis, which makes the cell membrane lose its integrity, eventually leading to the release of cytokines interleukin(IL)-1β and IL-18. When the body is infected with pathogens or exposed to some stimulations, pyroptosis could play an immune defense role. It is found that pyroptosis exists widely in infectious and inflammatory respiratory diseases such as acute lung injury, bronchial dysplasia, chronic obstructive pulmonary disease, and asthma. Excessive pyroptosis may accompany airway inflammation, tissue injury, and airway damage, and induce an inflammatory reaction, leading to more serious damage and poor prognosis of respiratory diseases. This review summarizes the relationship between pyroptosis and related respiratory diseases.

Expression of Major Lipid Raft Protein Raftlin in Chronic Rhinosinusitis with Nasal Polyps in Smoking and Non-Smoking Patients Correlated with Interleukin-17 and Tumor Necrosis Factor-α Levels

Raftlin, as an inflammatory biomarker, has been previously reported in chronic inflammatory diseases. This study investigates the expression of Raftlin in cigarette smokers and in chronic rhinosinusitis with nasal polyps (CRSwNP), as well as evaluating its correlation with interleukin-17 (IL-17) and tumor necrosis factor-α (TNF-α) levels. A total of 30 CRSwNP non-smoking and 16 CRSwNP + SK (smoking) patients undergoing endoscopic sinus surgery were enrolled, while 20 middle turbinate tissue pieces were examined and performed as the control group. In nasal mucosa epithelial staining, Raftlin levels were elevated in the columnar cells and were stained much more intensely in the CRSwNP and CRSwNP + SK groups. Raftlin was located more closely to the apical region of the epithelium in the CRSwNP + SK group; however, the Raftlin levels from whole nasal tissue pieces, according to ELISA data, showed that there was no significant difference between the three different study groups. A positive relationship by Pearson correlation was found between IL-17 or TNF-α levels and Raftlin levels. Taken together, these data indicate that increasing Raftlin expression in columnar cells might involve nasal epithelial remodeling in smokers with CRSwNP.