Inflammatory mechanisms and remodeling in chronic rhinosinusitis and nasal polyps

Evaluation of CNPase and TGFβ1/Smad Signalling Pathway Molecule Expression in Sinus Epithelial Tissues of Patients with Chronic Rhinosinusitis with (CRSwNP) and without Nasal Polyps (CRSsNP)

Chronic rhinosinusitis with and without nasal polyps (CRSwNP and CRSsNP, respectively) is a chronic inflammatory disease affecting almost 5 to 12% of the population and exhibiting high recurrence rates after functional endoscopic sinus surgery (FESS). TGFβ1-related pathways contribute to tissue remodelling, which is one of the key aspects of CRS pathogenesis. Additionally, adenosine signalling participates in inflammatory processes, and CNPase was shown to elevate adenosine levels by metabolizing cyclic monophosphates. Thus, the aim of this study was to assess the expression levels of Smad2, pSmad3, TGFβ1, and CNPase protein via immunohistochemistry in sinus epithelial tissues from patients with CRSwNP (n = 20), CRSsNP (n = 23), and non-CRS patients (n = 8). The expression of Smad2, pSmad3, TGFβ1, and CNPase was observed in the sinus epithelium and subepithelial area of all three groups of patients, and their expression correlated with several clinical symptoms of CRS. Smad2 expression was increased in CRSsNP patients compared to CRSwNP patients and controls (p = 0.001 and p < 0.001, respectively), pSmad3 expression was elevated in CRSwNP patients compared to controls (p = 0.007), TGFβ1 expression was elevated in CRSwNP patients compared to controls (p = 0.009), and CNPase was decreased in CRSsNP patients compared to controls (p = 0.03). To the best of our knowledge, we are the first to demonstrate CNPase expression in the upper airway epithelium of CRSwNP, CRSsNP, and non-CRS patients and point out a putative synergy between CNPase and TGFβ1/Smad signalling in CRS pathogenesis that emerges as a novel still undiscovered aspect of CRS pathogenesis; further studies are needed to explore its function in the course of the chronic inflammation of the upper airways.

Inhibitory effect of doxycycline conjugated with deoxycholic acid and polyethylenimine conjugate on nasal fibroblast differentiation and extracellular production

BACKGROUND

Chronic rhinosinusitis (CRS) is an inflammatory disease affecting the sinuses or nose. Persistent inflammatory responses can lead to tissue remodeling, which is a pathological characteristics of CRS. Activation of fibroblasts in the nasal mucosal stroma, differentiation and collagen deposition, and subepithelial fibrosis have been associated with CRS.

OBJECTIVES

We aimed to assess the inhibitory effects of doxycycline and deoxycholic acid-polyethyleneimine conjugate (DA3-Doxy) on myofibroblast differentiation and extracellular matrix (ECM) production in nasal fibroblasts stimulated with TGF-β1.

METHODS

To enhance efficacy, we prepared DA3-Doxy using a conjugate of low-molecular-weight polyethyleneimine (PEI) (MW 1800) and deoxycholic acid (DA) and Doxy. The synthesis of the DA3-Doxy polymer was confirmed using nuclear magnetic resonance, and the critical micelle concentration required for cationic micelle formation through self-assembly was determined. Subsequently, the Doxy loading efficiency of DA3 was assessed. The cytotoxicity of Doxy, DA3, PEI, and DA-Doxy in nasal fibroblasts was evaluated using the WST-1 assay. The anti-tissue remodeling and anti-inflammatory effects of DA3-Doxy and DA3 were examined using real-time polymerase chain reaction (Real-time PCR), immunocytochemistry, western blot, and Sircol assay.

RESULTS

Both DA3 and DA3-Doxy exhibited cytotoxicity at 10 μg/ml in nasal fibroblasts. Doxy partially inhibited α-smooth muscle actin, collagen types I and III, and fibronectin. However, DA3-Doxy significantly inhibited α-SMA, collagen types I and III, and fibronectin at 5 μg/ml. DA3-Doxy also modulated TGF-β1-induced changes in the expression of MMP 1, 2, and 9. Nonetheless, TGF-β1-induced expression of MMP3 was further increased by DA3-Doxy. The expression of TIMP 1 and 2 was partially reduced with 5 μg/ml DA3-Doxy.

CONCLUSIONS

Although initially developed for the delivery of genetic materials or drugs, DA3 exhibits inhibitory effects on myofibroblast differentiation and ECM production. Therefore, it holds therapeutic potential for CRS, and a synergistic effect can be expected when loaded with CRS treatment drugs.

Pediatric chronic rhinosinusitis

PURPOSE

An up-to-date overview of diagnosis, differential diagnosis, comorbidities, and current medical and surgical management of pediatric chronic rhinosinusitis (PCRS).

METHODS

Review of current evidence-based literature on PCRS.

RESULTS

Diagnosis of PCRS seems to be improving based on recent evidence using nasal endoscopy as well as computed tomography scanning. Recent literature supports the fact that chronic adenoiditis can be an independent etiology of symptoms of chronic sinusitis, that are very similar to chronic adenoiditis. Allergic rhinitis and immune deficiency play important roles in the management of PCRS. Surgery for PCRS has evolved significantly in the last 15-20 years to include adenoidectomy as well as endoscopic sinus surgery.

CONCLUSIONS

PCRS is very common in children causing poor QOL for these children. Medical management remains the main stay of treatment with attention to management of co-morbidities that may contribute to the disease severity. Making the correct diagnosis will help with the choice of surgical intervention if medical management fails.

Unraveling the Role of Epithelial Cells in the Development of Chronic Rhinosinusitis

The pathophysiology of CRS is multifactorial and complex yet needs to be completed. Recent evidence emphasizes the crucial part played by epithelial cells in the development of CRS. The epithelial cells act as physical barriers and play crucial roles in host defense, including initiating and shaping innate and adaptive immune responses. This review aims to present a comprehensive understanding of the significance of nasal epithelial cells in CRS. New research suggests that epithelial dysfunction plays a role in developing CRS through multiple mechanisms. This refers to issues with a weakened barrier function, disrupted mucociliary clearance, and irregular immune responses. When the epithelial barrier is compromised, it can lead to the passage of pathogens and allergens, triggering inflammation in the body. Furthermore, impaired mucociliary clearance can accumulate pathogens and secretions of inflammatory mediators, promoting chronic inflammation. Epithelial cells can release cytokines and chemokines, which attract and activate immune cells. This can result in an imbalanced immune response that continues to cause inflammation. The interaction between nasal epithelial cells and various immune cells leads to the production of cytokines and chemokines, which can either increase or decrease inflammation. By comprehending the role of epithelial cells in CRS, we can enhance our understanding of the disease's pathogenesis and explore new therapeutics.

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.

Immunohistochemical expression of estrogen receptor alpha in the maxillary sinus, pulp, and periodontal ligament of adjacent teeth in late pregnancy in rats

This study aimed to assess the histological changes in the maxillary sinus and its adjacent dental tissues as pulp and periodontal ligament during pregnancy and investigate the role of estrogen hormone in these changes through the detection of estrogen receptors in these tissues. Sixteen adult female rats were used and were allocated into two groups: control non-pregnant (n = 8) and pregnant (n = 8). They were sacrificed and their heads were prepared for histological and immunohistochemical examination for estrogen receptor alpha. Our results revealed that pregnant rats revealed inflammatory changes in the sinus as thick epithelial lining, loss of cilia, swollen goblet cells, intraepithelial and interstitial edema. The lamina propria demonstrated considerable infiltration of inflammatory cells, glandular hyperplasia with vacuolar degeneration, and vascular congestion. Periodontal ligament and pulp revealed hyperemia and vascular congestion. Immunohistochemical examination of estrogen receptor alpha in the maxillary sinus and adjacent dental tissues (Periodontal ligament and pulp) in pregnant rats revealed a significant increase in its expression in all examined tissues. In conclusion, there was an increase in expression of ERα in the sinus mucosa and dental tissues during pregnancy together with slight inflammatory changes in these tissues. Hence, dentists should be aware of the effect of these changes on the pregnant women avoiding teeth extraction due to misdiagnosis of dental, periodontal or sinus pain after exclusion of true pathologies.

MEX3B inhibits collagen production in eosinophilic nasal polyps by downregulating epithelial cell TGFBR3 mRNA stability

Although the expression of Mex3 RNA-binding family member B (MEX3B) is upregulated in human nasal epithelial cells (HNECs) predominately in the eosinophilic chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) subtype, its functions as an RNA binding protein in airway epithelial cells remain unknown. Here, we revealed the role of MEX3B based on different subtypes of CRS and demonstrated that MEX3B decreased the TGF-β receptor III (TGFBR3) mRNA level by binding to its 3' UTR and reducing its stability in HNECs. TGF-βR3 was found to be a TGF-β2-specific coreceptor in HNECs. Knocking down or overexpressing MEX3B promoted or inhibited TGF-β2-induced phosphorylation of SMAD2 in HNECs, respectively. TGF-βR3 and phosphorylated SMAD2 levels were downregulated in CRSwNP compared with controls and CRS without nasal polyps with a more prominent downregulation in the eosinophilic CRSwNP. TGF-β2 promoted collagen production in HNECs. Collagen abundance decreased and edema scores increased in CRSwNP compared with control, again more prominently in the eosinophilic type. Collagen expression in eosinophilic CRSwNP was negatively correlated with MEX3B but positively correlated with TGF-βR3. These results suggest that MEX3B inhibits tissue fibrosis in eosinophilic CRSwNP by downregulating epithelial cell TGFBR3 expression; consequently, MEX3B might be a valuable therapeutic target against eosinophilic CRSwNP.

BMP-2 and IL-1β as Markers of Nasal Mucosa Inflammation in Rhinosinusitis with Nasal Polyps

Rhinosinusitis with nasal polyps is characterized by chronic inflammation and hyperplasia of the nasal mucosa. The key mechanism for polyp formation is the expression of molecules that regulate proliferation and inflammation. We studied immunolocalization of bone morphogenetic protein-2 (BMP-2) and IL-1β in the nasal mucosa in patients aged 35-70 years (n=70, mean age 57.4±1.52 years). The typology of polyps was determined depending on the distribution of inflammatory cells, subepithelial edema, the presence of fibrosis and cysts. The immunolocalization of BMP-2 and IL-1β had the same pattern in edematous, fibrous, and eosinophilic (allergic) polyps. Goblet and connective tissue cells, microvessels and terminal sections of the glands were positively stained. BMP-2⁺ and IL-1β⁺ cells predominated in polyps of the eosinophilic type. BMP-2/IL-1β can be considered as a specific marker of inflammatory remodeling of the nasal mucosa in refractory rhinosinusitis with nasal polyps.

Savory Signaling: T1R Umami Receptor Modulates Endoplasmic Reticulum Calcium Store Content and Release Dynamics in Airway Epithelial Cells

T1Rs are expressed in solitary chemosensory cells of the upper airway where they detect apical glucose levels and repress bitter taste receptor Ca²⁺ signaling pathways. Microbial growth leads to a decrease in apical glucose levels. T1Rs detect this change and liberate bitter taste receptor signaling, initiating an innate immune response to both kill and expel pathogens through releasing antimicrobial peptides and increasing nitric oxide production and ciliary beat frequency. However, chronic inflammation due to disease, smoking, or viral infections causes a remodeling of the epithelial airway. The resulting squamous metaplasia causes a loss of multi-ciliated cells and solitary chemosensory cells, replaced by basal epithelial cells. To understand how T1R function is altered during disease, we used basal epithelial cells as a model to study the function of T1R3 on Ca²⁺ signaling dynamics. We found that both T1R1 and T1R3 detect amino acids and signal via cAMP, increasing the responsiveness of the cells to Ca²⁺ signaling stimuli. Either knocking down T1R1/3 or treating wild-type cells with MEM amino acids caused a reduction in ER Ca²⁺ content through a non-cAMP signaled pathway. Treatment with amino acids led to a reduction in downstream denatonium-induced Ca²⁺-signaled caspase activity. Thus, amino acids may be used to reduce unwanted apoptosis signaling in treatments containing bitter compounds.

Immunopathologic Role of Eosinophils in Eosinophilic Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a diverse chronic inflammatory disease of the sinonasal mucosa. CRS manifests itself in a variety of clinical and immunologic patterns. The histological hallmark of eosinophilic CRS (ECRS) is eosinophil infiltration. ECRS is associated with severe disease severity, increased comorbidity, and a higher recurrence rate, as well as thick mucus production. Eosinophils play an important role in these ECRS clinical characteristics. Eosinophils are multipotential effector cells that contribute to host defense against nonphagocytable pathogens, as well as allergic and nonallergic inflammatory diseases. Eosinophils interact with Staphylococcus aureus, Staphylococcal enterotoxin B, and fungi, all of which were found in the tissue of CRS patients. These interactions activate Th2 immune responses in the sinonasal mucosa and exacerbate local inflammation. Activated eosinophils were discovered not only in the tissue but also in the sinonasal cavity secretion. Eosinophil extracellular traps (EETs) are extracellular microbes trapping and killing structures found in the secretions of CRS patients with intact granule protein and filamentous chromatic structures. At the same time, EET has a negative effect by causing an epithelial barrier defect. Eosinophils also influence the local tissue microenvironment by exchanging signals with other immune cells and structural cells. As a result, eosinophils are multifaceted leukocytes that contribute to various physiologic and pathologic processes of the upper respiratory mucosal immune system. The goal of this review is to summarize recent research on the immunopathologic properties and immunologic role of eosinophils in CRS.

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.

Microvessel quantification by fully convolutional neural networks associated with type 2 inflammation in chronic rhinosinusitis

BACKGROUND

The pathogenesis of chronic rhinosinusitis (CRS) is still unclear, and little is known about angiogenesis in this disease. We utilized a fully convolutional network (FCN), which has been extensively used in image processing to study angiogenesis in CRS.

OBJECTIVE

To explore the tissue quantification of microvessels and their potential association with inflammation in CRS by using FCN to reflect the angiogenesis condition in CRS.

METHODS

For endotyping of CRS, tissue homogenates of 79 patients with CRS who had undergone functional endoscopic sinus surgery and 17 control subjects were analyzed for interferon gamma, transforming growth factor beta, interleukin (IL)-1β, IL-5, IL-6, IL-8, IL-10, IL-17, tumor necrosis factor alpha, eosinophilic cationic protein, immunoglobulin E, and Staphylococcus aureus-immunoglobulin E(SE-IgE). A total of 552 hematoxylin and eosin-stained images of 27 CRS tissue samples were used to develop an FCN, going through training, validation, and evaluation processes. An optimized FCN was applied to quantify the microvessels of tissue samples of all subjects. Correlation analysis between microvessel quantification with phenotype, endotype, clinical characteristics, and cytokine expression of CRS was carried out.

RESULTS

Quantification of microvessels in type 2 and non-type 2 CRS demonstrated considerable differences, with a higher expression in type 2 CRS. There was a strong negative correlation between the area ratio of microvessels with tissue tumor necrosis factor alpha and transforming growth factor beta levels and a mildly positive correlation with tissue IL-5 and eosinophilic cationic protein concentration.

CONCLUSION

FCN proved to facilitate the analysis of microvessels in airway tissue samples. This study elucidated the close association of angiogenesis with endotyping, suggesting that treatment aiming at antagonizing angiogenesis may assist to the therapy for the recrudescent and refractory CRS.

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.

Evaluation of MMP-12 expression in chronic rhinosinusitis with nasal polyposis

BACKGROUND

The purpose of this study was to evaluate the expression of MMP-12 in patients with chronic rhinosinusitis with polyps (CRSwNP).

METHODOLOGY

Tissue samples from 37 patients with CRSwNP undergoing functional endoscopic sinus surgery and healthy mucosa specimens from 12 healthy controls were obtained intraoperatively. The mRNA and protein expression levels of MMP-12 were quantified by real-time polymerase chain reaction and Western blotting, respectively.

RESULTS

mRNA levels of MMP-12 were significantly elevated in the CRSwNP tissue samples compared to those in control ones. The protein levels of MMP-12 showed a trend of increasing but with no statistical significance.

CONCLUSIONS

Elevation of MMP-12 in patients with CRSwNP suggests its potential implication in the pathogenesis of the disease. The difference in the expression profile observed between mRNA and protein levels could be due to post-translational gene expression regulation. Our findings provide evidence that MMP-12 along with other MMPs may serve as a biomarker and therapeutic target in the management of the disease.

Nasal polyp fibroblasts (NPFs)-derived exosomes are important for the release of vascular endothelial growth factor from cocultured eosinophils and NPFs

OBJECTIVE

Significant eosinophil infiltration and tissue remodeling are common characteristics of conditions associated with chronic airway inflammation, such as chronic rhinosinusitis with nasal polyp and bronchial asthma. This study was designed to elucidate the role of eosinophil-fibroblast interactions in tissue remodeling during chronic airway inflammation.

METHODS

Peripheral blood eosinophils or EoL-1 eosinophilic leukemia cells were cocultured with nasal polyp fibroblasts (NPFs). Coculture-induced release of exosomes, major components of extracellular vesicles (EVs), and a profibrotic cytokine, vascular endothelial growth factor (VEGF), were evaluated by enzyme-linked immunosorbent assay.

RESULTS

Eosinophil-NPF interactions stimulated the release of exosomes and VEGF into culture supernatants. Coculture-induced release of exosomes was stimulated earlier than VEGF release, at 3 h of incubation. The average size of the EVs released by NPFs was 133 ± 3.6 nm. NPF-derived EVs (exosome concentration: 25 pg/mL) significantly stimulated VEGF release from EoL-1 cells. Pretreatment of NPFs with exosome inhibitor, GW4869 or DMA attenuated the release of exosomes and VEGF from cocultured EoL-1 cells and NPFs.

CONCLUSION

The results of this study indicate that eosinophil-fibroblast interactions are important in the pathophysiology of tissue remodeling in eosinophil-predominant airway inflammation and that NPF-derived exosomes play a crucial role in the release of VEGF.

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.

17,18-Epoxyeicosatetraenoic Acid Inhibits TNF-α-Induced Inflammation in Cultured Human Airway Epithelium and LPS-Induced Murine Airway Inflammation

BACKGROUND

17,18-Epoxyeicosatetraenoic acid (17,18-EpETE), an eicosapentaenoic acid metabolite, is generated from dietary oil in the gut, and antiinflammatory activity of 17,18-EpETE was recently reported.

OBJECTIVE

To evaluate the inhibitory effects of 17,18-EpETE in airway inflammation, we examined in vitro and in vivo effects on mucus production, neutrophil infiltration, and cytokine/chemokine production in airway epithelium.

METHODS

Nasal tissue localization of G protein-coupled receptor 40 (GPR40), a receptor of 17,18-EpETE, was determined by immunohistochemical staining. Expression of GPR40 mRNA in nasal mucosa of chronic rhinosinusitis (CRS) patients and control subjects was determined by reverse transcription-polymerase chain reaction (RT-PCR). The in vitro effects on airway epithelial cells were examined using normal human bronchial epithelial cells and NCI-H292 cells. To examine the in vivo effects of 17,18-EpETE on airway inflammation, we induced goblet cell metaplasia, mucus production, and neutrophil infiltration in mouse nasal epithelium by intranasal lipopolysaccharide (LPS) instillation.

RESULTS

GPR40 is mainly expressed in human nasal epithelial cells and submucosal gland cells. RT-PCR analysis revealed that the expression of GPR40 mRNA was increased in nasal tissues from CRS patients compared with those from control subjects. 17,18-EpETE significantly inhibited tumor necrosis factor (TNF)-α-induced production of interleukin (IL)-6 , IL-8, and mucin from cultured human airway epithelial cells dose dependently, and these antiinflammatory effects on cytokine production were abolished by GW1100, a selective GPR40 antagonist. Intraperitoneal injection or intranasal instillation of 17,18-EpETE significantly attenuated LPS-induced mucus production and neutrophil infiltration in mouse nasal epithelium. Inflammatory cytokine/chemokine production in lung tissues and bronchoalveolar lavage fluids was also inhibited.

CONCLUSION

These results indicate that 17,18-EpETE plays a regulatory role in mucus hypersecretion and neutrophil infiltration in nasal inflammation. Local or systemic administration may provide a new therapeutic approach for the treatment of intractable airway disease such as CRS.

Matrix metalloproteinases and chronic rhinosinusitis with nasal polyposis. Unravelling a puzzle through a systematic review

BACKGROUND

The expression of metalloproteinases (MMPs) in chronic rhinosinusitis with nasal polyposis (CRSwNP) was reviewed in order to investigate their possible use as therapeutical targets and/or biomarkers.

METHODOLOGY

The differences between CRSwNP and normal controls or CRS without NP, as well as the effects of various treatments on MMPs, tissue inhibitors of MMPs (TIMPs) and MMP/TIMP ratios were considered as primary outcomes. Additional factors reported to affect MMP expression levels were noted as secondary outcomes. Data regarding inflammatory subtypes, patients’ clinical characteristics, controls, laboratory method(s) and origin of samples were also pooled. Studies on 10 or fewer patients or on specimens other than nasal and serum were excluded.

RESULTS

Forty-three studies were included. Tissue sample origin, allergic rhinitis, smoking, infection, medication intake and primary or recurrent disease should be considered as confounding factors for MMP levels. MMP-1 and -7 were consistently found to be significantly higher in CRSwNP patients than controls. CRSwNP endotypes with distinctly different inflammation patterns seem to present similar MMP-related remodelling patterns.

CONCLUSIONS

The existing literature has revealed several population and methodology related confounding factors and remains inconclusive regarding the roles of MMPs in CRSwNP pathophysiology and their possible clinical usefulness as biomarkers and therapeutical targets.

p63+Krt5+ basal cells are increased in the squamous metaplastic epithelium of patients with radiation-induced chronic Rhinosinusitis

Background

Squamous metaplasia (SM) is an irreversible form of airway epithelial remodeling. Hyperproliferation of basal cells was observed in squamous metaplastic epithelium of chronically inflamed airway. However, the association of such aberrant proliferation of basal cells with SM in the nasal epithelium after radiation damage remains unclear. The aim of this study was to investigate SM and accompanying levels of p63⁺Krt5⁺ (basal cell markers) cells in the nasal epithelium of patients with radiation-induced chronic rhinosinusitis (CRSr) and patients with chronic rhinosinusitis without nasal polyps (CRSsNP) compared to healthy controls.

Methods

We assessed the prevalence of SM and the expression of p63⁺, Krt5⁺, p63⁺Krt5⁺, and Ki67⁺ cells through immunofluorescence(IF) staining of the inferior turbinate (IT) tissues from patients with CRSr (n = 36), CRSsNP (n = 33) and controls (n = 28).

Results

The prevalence of SM and the number of p63⁺Krt5⁺ cells were both significantly increased in patients with CRSr compared to patients with CRSsNP and controls. The number of Ki67⁺ cells were both significantly increased in patients with CRSr and CRSsNP compared to controls, but the ratio of Ki67⁺ cells to p63⁺Krt5⁺ cells was significantly lower in patients with CRSr compared to patients with CRSsNP. In patients with CRSr, an increased number of p63⁺Krt5+ basal cells was observed in SM epithelium compared to non-SM epithelium.

Conclusion

SM is increased in the nasal epithelium of patients with CRSr, in which aberrant levels of p63⁺Krt5⁺ basal cells serves as an important pathologic feature in the squamous metaplastic epithelium.

Q192R polymorphism in the PON1 gene and nasal polyp in a Turkish population

The pathogenesis of nasal polyps is not completely understood. Oxidative damage contributes to polyp formation in the nasal mucosa. The paraoxonase 1 (PON1) enzyme is an important liver enzyme with high antioxidant activity. In this study, we investigated the correlation between Q192R genotypic polymorphism of the PON1 enzyme and nasal-polyp disease. The study examined 62 nasal-polyp patients and 88 controls. PON1 Q192R polymorphism was determined using polymerase chain reaction-restriction fragment length polymorphism. The genotype distribution of the PON1 gene was significantly different between nasal-polyp patients (QQ = 69.35%, QR = 25.81%, RR = 4.83%) and healthy controls (QQ = 52.27%, QR = 44.31%, RR = 3.40%). Our results suggest that the PON1 QQ genotype (odds ratio [OR] = 2.066, P = .036) is associated with a higher risk of developing the nasal-polyp disease while QR genotype (OR = 0.437, P = .021) showed a lower risk.

[Expression of pro- and anti-apoptotic molecules in the mucous membrane of the nasal cavity with polypous rhinosinusitis]

OBJECTIVE

To study the expression of proapoptotic (p53, p21) and antiapoptotic (MDM2) factors, as well as the distribution of proliferating PCNA-immunoreactive cells in the nasal mucosa in various types of polyposis rhinosinusitis (PRS).

MATERIAL AND METHODS

We studied the immunolocalization of proapoptotic (p53, p21) and antiapoptotic (MDM2) factors, as well as the distribution of proliferating PCNA immunoreactive cells in the mucous membrane of the nasal cavity for various types of polypous rhinosinusitis.

RESULTS AND DISCUSSION

Comparing with the control group, increased expression of all factors is detected. The main portion of marked cells is located in the loose connective tissue of the lamina propria of mucous membrane, a relatively small number of cells are detected in the epithelial layer. The edematous, eosinophilic (allergic) type of PRS is characterized by the expression of p53 and PCNA and by the reduction of MDM2 immunoreactive cells, while the expression of p53 and p21 is reduced in fibroinflammatory (neutrophilic) type.

CONCLUSION

PRS is accompanied by epithelial metaplasia, by formation of inflammatory cell infiltrates, fibrosis and edema. The results are discussed in connection with the data on the regulatory role of apoptosis in the pathomorphism of chronic productive inflammation.

Expression and Clinical Significance of Mucin Gene in Chronic Rhinosinusitis

PURPOSE OF REVIEW

This review highlights the expression and regulation of mucin in CRS and discusses its clinical implications.

RECENT FINDINGS

Chronic rhinosinusitis (CRS) is common chronic nasal disease; one of its main manifestations and important features is mucus overproduction. Mucin is the major component of mucus and plays a critical role in the pathophysiological changes in CRS. The phenotype of CRS affects the expression of various mucins, especially in nasal polyps (NP). Corticosteroids(CS), human neutrophil elastase (HNE), and transforming growth factor-β1 (TGF-β1) are closely related to the tissue remodeling of CRS and regulate mucin expression, mainly MUC1, MUC4, MUC5AC, and MUC5B. "It is expected that CS, HNE and TGF - β could be used to regulate the expression of mucin in CRS." However, at present, the research on mucin is mainly focused on mucin 5AC and mucin 5B, which is bad for finding new therapeutic targets. Investigating the expression and location of mucin in nasal mucosa and understanding the role of various inflammatory factors in mucin expression are helpful to figure out regulatory mechanisms of airway mucin hypersecretion. It is of great significance for the treatment of CRS.

Squamous Cell Carcinoma In Situ Originating From Nasal Polyps With Human Papillomavirus 51 Infection: A Case Report

Malignant transformation of nasal polyps is extremely rare in cases without background inverted papilloma. Human papillomavirus (HPV) is a sexually transmitted infection believed to be associated with oropharyngeal carcinoma via oro-genital sexual contact. We present a case of focal squamous cell carcinoma in situ that occurred on the surface of nasal polyps and was associated with HPV 51. The patient was successfully treated with endoscopic sinus surgery. Clinicians should be aware of the potential for hidden malignancies, and pathologic assessment of tissue specimens must be performed even in simple nasal polyp cases.

Polarization of protease-activated receptor 2 (PAR-2) signaling is altered during airway epithelial remodeling and deciliation

Protease-activated receptor 2 (PAR-2) is activated by secreted proteases from immune cells or fungi. PAR-2 is normally expressed basolaterally in differentiated nasal ciliated cells. We hypothesized that epithelial remodeling during diseases characterized by cilial loss and squamous metaplasia may alter PAR-2 polarization. Here, using a fluorescent arrestin assay, we confirmed that the common fungal airway pathogen Aspergillus fumigatus activates heterologously-expressed PAR-2. Endogenous PAR-2 activation in submerged airway RPMI 2650 or NCI-H520 squamous cells increased intracellular calcium levels and granulocyte macrophage-colony-stimulating factor, tumor necrosis factor α, and interleukin (IL)-6 secretion. RPMI 2650 cells cultured at an air-liquid interface (ALI) responded to apically or basolaterally applied PAR-2 agonists. However, well-differentiated primary nasal epithelial ALIs responded only to basolateral PAR-2 stimulation, indicated by calcium elevation, increased cilia beat frequency, and increased fluid and cytokine secretion. We exposed primary cells to disease-related modifiers that alter epithelial morphology, including IL-13, cigarette smoke condensate, and retinoic acid deficiency, at concentrations and times that altered epithelial morphology without causing breakdown of the epithelial barrier to model early disease states. These altered primary cultures responded to both apical and basolateral PAR-2 stimulation. Imaging nasal polyps and control middle turbinate explants, we found that nasal polyps, but not turbinates, exhibit apical calcium responses to PAR-2 stimulation. However, isolated ciliated cells from both polyps and turbinates maintained basolateral PAR-2 polarization, suggesting that the calcium responses originated from nonciliated cells. Altered PAR-2 polarization in disease-remodeled epithelia may enhance apical responses and increase sensitivity to inhaled proteases.

Eosinophil-derived neurotoxin enhances airway remodeling in eosinophilic chronic rhinosinusitis and correlates with disease severity

Eosinophilic chronic rhinosinusitis (ECRS) is a subtype of chronic rhinosinusitis (CRS) that is characterized by intractable nasal polyp formation. Eosinophil-derived neurotoxin (EDN) is an eosinophil granule protein that is closely related to allergic inflammation, but the pathological implications of EDN in ECRS remain unknown. In this study, we evaluated the function of EDN in ECRS pathogenesis and assessed its potential as a disease activity marker. Serum EDN levels were significantly higher in patients with ECRS than in those with other nasal and paranasal diseases, and were positively correlated with clinical disease activity. Production of EDN from isolated human eosinophils was induced by stimulation with IL-5 in vitro. Human nasal epithelial cells were stimulated with EDN, and the resultant changes in gene expression were detected by RNA sequencing. Pathway analysis revealed that the major canonical pathway affected by EDN stimulation was 'regulation of the epithelial-mesenchymal transition pathway'; the only gene in this pathway to be up-regulated was matrix metalloproteinase 9 (MMP-9). Consistent with this, immunostaining analysis revealed intense staining of both EDN and MMP-9 in nasal polyps from patients with ECRS. In conclusion, our data demonstrate that serum EDN level is a useful marker for the evaluation of ECRS severity. Furthermore, EDN induces production of MMP-9 from the nasal epithelium, which may be involved in the pathogenesis of ECRS.

Correlation Between HMGB1 and TLR4 Expression in Sinonasal Mucosa in Patients With Chronic Rhinosinusitis

OBJECTIVES

Chronic rhinosinusitis (CRS) is one of the most common inflammations in the upper airway. Despite the wide prevalence of CRS, the pathogenesis of this disease is poorly understood. Several components of the innate immune system may play a significant role in CRS, including Toll-like receptor 4 (TLR4), TLR9, and high-mobility group box 1 protein (HMGB1). This study was conducted to determine the expression of TLR4, TLR9, HMGB1, and pNFκ-B p65 in paraffin-embedded blocks of patients with CRS with nasal polyps compared with those of the control group.

METHODS

Twenty-six formalin-fixed, paraffin-embedded samples from patients with confirmed CRS and 26 patients undergoing septoplasty due to anatomic variations and no other inflammatory nasal diseases as the control group were assessed. Expression patterns of HMGB1, TLR9, TLR4, and pNFκ-B p65 genes were examined using real-time quantitative reverse transcription polymerase chain reaction (Real-Time qRT-PCR). Statistical analyses were performed with SPSS and analyzed using unpaired 2-tailed t tests or 1-way analysis of variance.

RESULTS

Real-time PCR showed that the expression level of HMGB1 messenger RNA was significantly increased in the tissues of patients with CRS compared with controls (P < .05). The other 3 genes were also upregulated in the patients, but were not significant compared with control. Analysis of the Pearson correlation coefficient (r) revealed a significant positive correlation between HMGB1 and TLR4 (r = 0.79, P < .05) in patients and negative correlation between TLR4 and NfκB in the control group (r = 0.94; P < .05).

CONCLUSIONS

Both HMGB1 and TLR4 are increased in the paranasal sinus mucosa of patients with CRS. These results suggest a possible contribution of HMGB1 and its internal receptor (TLR4) in the pathophysiology of CRS.

Different effects of allergic rhinitis on nasal mucosa remodeling in chronic rhinosinusitis with and without nasal polyps

Background

Allergic rhinitis (AR) has been reported to be associated with chronic rhinosinusitis (CRS). The objective of this study was to investigate the effect of AR on nasal mucosa remodeling in CRS.

Methods

Patients were enrolled and divided into the following groups: CRS with nasal polyps (NP) with allergic rhinitis (AR)(CRSwNPwAR; n = 20), CRS with NP without AR (CRSwNPsAR; n = 20), CRS without NP with AR (CRSsNPwAR; n = 20), CRS without NP without AR (CRSsNPsAR; n = 20), AR without CRS (AR; n = 20) and controls (n = 14). Eosinophil infiltration, mucus production, and collagen deposition were examined by hematoxylin and eosin, periodic acid schiff and masson’s trichrome staining, respectively. VEGF-A and microvessel density were detected by immunohistochemistry. The expression of remodeling markers, including TGF-β1, MMP-7, MMP-9 and TIMP-1 were measured by Western blot.

Results

The expression of remodeling factors, including VEGF-A, CD31, CD34 and TIMP-1 were significantly increased in CRSwAR compared to CRSsAR. Goblet cell hyperplasia, as well as VEGF-A, CD31, CD34, and MMP-9 expression were significantly higher in CRSwNPwAR compared to CRSwNPsAR. However, the expression of collagen fibers, MMP-7 and TGF-β1 were significantly higher in CRSsNPwAR compared to CRSsNPsAR.

Conclusions

AR could enhance the remodeling process in CRS. Moreover, AR had different effects on CRSwNP and CRSsNP.

Is there any effect of neurotrophin-3 on the pathogenesis of non-allergic nasal polyps?

BACKGROUND

Although the role of neurotrophins such as nerve growth factor and brain-derived neurotrophic factor in nasal polyps development has been studied, the contribution of neurotrophin-3 has not been evaluated yet. This study aimed to investigate the possible role of neurotrophin-3 in nasal polyps pathogenesis.

METHODS

The study group comprised 70 non-allergic nasal polyps patients and the control group consisted of 53 patients with middle turbinate concha bullosa. Specimens were taken, during surgery, from the ethmoid sinus nasal polyps in the nasal polyps group and from the lateral part of the middle turbinate concha bullosa in the control group. Tissue and serum levels of neurotrophin-3 were assessed by immunohistochemistry and enzyme-linked immunosorbent assay, respectively.

RESULTS

Nasal polyps patients had higher tissue neurotrophin-3 scores (p < 0.001). There was no statistically significant difference between groups regarding serum neurotrophin-3 levels (p = 0.417). Tissue neurotrophin-3 staining scores in the nasal polyps group had no statistically significant correlation with Lund-Mackay scores (p = 0.792).

CONCLUSION

Neurotrophin-3 may have a local effect in nasal polyps pathogenesis, without joining systemic circulation.

Amphiregulin-Producing Pathogenic Memory T Helper 2 Cells Instruct Eosinophils to Secrete Osteopontin and Facilitate Airway Fibrosis

Memory T cells provide long-lasting protective immunity, and distinct subpopulations of memory T cells drive chronic inflammatory diseases such as asthma. Asthma is a chronic allergic inflammatory disease with airway remodeling including fibrotic changes. The immunological mechanisms that induce airway fibrotic changes remain unknown. We found that interleukin-33 (IL-33) enhanced amphiregulin production by the IL-33 receptor, ST2^hi memory T helper 2 (Th2) cells. Amphiregulin-epidermal growth factor receptor (EGFR)-mediated signaling directly reprogramed eosinophils to an inflammatory state with enhanced production of osteopontin, a key profibrotic immunomodulatory protein. IL-5-producing memory Th2 cells and amphiregulin-producing memory Th2 cells appeared to cooperate to establish lung fibrosis. The analysis of polyps from patients with eosinophilic chronic rhinosinusitis revealed fibrosis with accumulation of amphiregulin-producing CRTH2^hiCD161^hiCD45RO⁺CD4⁺ Th2 cells and osteopontin-producing eosinophils. Thus, the IL-33-amphiregulin-osteopontin axis directs fibrotic responses in eosinophilic airway inflammation and is a potential target for the treatment of fibrosis induced by chronic allergic disorders.

The potential of Olea europaea extracts to prevent TGFβ1-induced epithelial to mesenchymal transition in human nasal respiratory epithelial cells

Background

One of the molecular mechanisms involved in upper airway-related diseases is epithelial-to-mesenchymal transition (EMT). Olea europaea (OE) has anti-inflammatory properties and thus, great potential to prevent EMT. This study aimed to investigate the effect of OE on EMT in primary nasal human respiratory epithelial cells (RECs).

Methods

Respiratory epithelial cells were isolated and divided into four groups: control (untreated), treated with 0.05% OE (OE group), EMT induced with 5 ng/ml of transforming growth factor beta-1 (TGFβ1 group) and treated with 5 ng/ml TGFβ1 + 0.05% OE (TGFβ1 + OE group). The effects of OE treatment on growth kinetics, morphology and protein expression in RECs were evaluated. Immunocytochemistry analysis was performed to quantitate the total percentage of E-cadherin and vimentin expression from day 1 to day 3.

Results

There were no significant differences between untreated RECs and OE-treated RECs in terms of their morphology, growth kinetics and protein expression. Induction with TGFβ1 caused RECs to have an elongated spindle shape, a slower proliferation rate, a higher expression of vimentin and a lower expression of E-cadherin compared with the control. Cells in the TGFβ1 + OE group had similar epithelial shape to untreated group however it had no significant differences in their proliferation rate when compared to TGFβ1-induced RECs. Cells treated with TGFβ1 + OE showed significantly reduced expression of vimentin and increased expression of E-cadherin compared with the TGFβ1 group (P < 0.05).

Conclusion

The ability of OE to inhibit EMT in RECs was shown by TGFb1-induced EMT REC morphology, growth kinetics and protein expression markers (E-cadherin and vimentin) upon treatment with OE and TGFβ1. Therefore, this study could provide insight into the therapeutic potential of OE to inhibit pathological tissue remodelling and persistent inflammation.

Microbiota Composition and the Integration of Exogenous and Endogenous Signals in Reactive Nasal Inflammation

The prevalence of reactive nasal inflammatory conditions, for example, allergic rhinitis and chronic rhinosinusitis, is steadily increasing in parallel with significant environmental changes worldwide. Allergens and as yet undefined environmental agents may trigger these conditions via the involvement of host intrinsic factors, including the innate and adaptive immune system, the nasal epithelium, and the nasal nervous system. The critical role of the nasal microbiota in coordinating these components has emerged in recent studies documenting a significant association between microbial composition and the onset and progression of allergic or nonallergic inflammation. It is now clear that the local microbiota is a major player in the development of the mucosa-associated lymphoid tissue and in the regulation of such adaptive responses as IgA production and the function of effector and regulatory T cells. Microbial components also play a major role in the regulation of epithelial barrier functions, including mucus production and the control of paracellular transport across tight junctions. Bacterial components, including lipopolysaccharide, have also been shown to induce or amplify neuroinflammatory responses by engaging specific nociceptors. Finally, bacterial products may promote tissue remodeling processes, including nasal polyp formation, by interacting with formyl peptide receptors and inducing the expression of angiogenic factors and matrix-degrading enzymes.

Aberrant expression of miR-663 and transforming growth factor-β1 in nasal polyposis in children

The aim of the present study was to investigate the expression of microRNA (miR)-663 and its regulatory effects on the pathogenesis of nasal polyposis in children. Nasal polyp tissue, as well as serum and peripheral blood eosinophils were collected from 35 children diagnosed with nasal polypectomy between August 2013 and August 2015. As a control, the inferior nasal concha, serum and peripheral blood eosinophils were collected from 46 patients with nasal septal deviation complicated by inferior turbinate hypertrophy or patients with simple inferior turbinate hypertrophy who had undergone surgical removal of the inferior nasal concha. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to measure the expression of miR-663 and transforming growth factor-β1 (TGF-β1) in the nasal polyp tissue, serum and peripheral blood eosinophils of patients with nasal polyposis and controls. Western blotting was used to measure the expression of TGF-β1 protein in nasal tissue and eosinophils and an enzyme-linked immunosorbent assay was used to measure serum level of TGF-β1 protein. A dual luciferase reporter assay was used to determine whether TGF-β1 was a target gene of miR-663. Compared with the control group, levels of TGF-β1 mRNA and protein were significantly increased in all three types of specimens from pediatric patients with nasal polyposis (P<0.05). miR-663 expression was significantly decreased in nasal polyp tissue and peripheral blood eosinophils (P<0.05). The dual luciferase reporter assay confirmed that TGF-β1 was a target gene of miR-663. The current study suggests that the upregulation of TGF-β1 may be associated with the downregulation of miR-663 in nasal polyposis in children. miR-663 may have regulatory effects on the pathogenesis of nasal polyposis by regulating TGF-β1 and may be developed as a genetic marker of nasal polyposis in children.

Clusterin Induces MUC5AC Expression via Activation of NF-κB in Human Airway Epithelial Cells

Objectives

Clusterin (CLU) is known as apolipoprotein J, and has three isoforms with different biological functions. CLU is associated with various diseases such as Alzheimer disease, atherosclerosis, and some malignancies. Recent studies report an association of CLU with inflammation and immune response in inflammatory airway diseases. However, the effect of CLU on mucin secretion of airway epithelial cells has not yet been understood. Therefore, the effect and brief signaling pathway of CLU on MUC5AC (as a major secreted mucin) expression were investigated in human airway epithelial cells.

Methods

In the tissues of nasal polyp and normal inferior turbinate, the presence of MUC5AC and CLU was investigated using immunohistochemical stain and Western blot analysis. In mucin-producing human NCI-H292 airway epithelial cells and primary cultures of normal nasal epithelial cells, the effect and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway of CLU on MUC5AC expression were investigated using immunohistochemical stain, reverse transcription-polymerase chain reaction, real-time polymerase chain reaction, enzyme immunoassay, and Western blot analysis.

Results

In the nasal polyps, MUC5AC and CLU were abundantly present in the epithelium on immunohistochemical stain, and nuclear CLU (nCLU) was strongly detected on Western blot analysis. In human NCI-H292 airway epithelial cells or the primary cultures of normal nasal epithelial cells, recombinant nCLU increased MUC5AC expression, and significantly activated phosphorylation of NF-κB. And BAY 11-7085 (a specific NF-κB inhibitor) and knockdown of NF-κB by NF-κB siRNA (small interfering RNA) significantly attenuated recombinant nCLU-induced MUC5AC expression.

Conclusion

These results suggest that nCLU induces MUC5AC expression via the activation of NF-κB signaling pathway in human airway epithelial cells.

Asthma management: A new phenotype-based approach using presence of eosinophilia and allergy

Asthma is a heterogeneous disease. The Czech Pneumology and Allergology Societies commissioned 10 experts to review the literature and create joint national guidelines for managing asthma, reflecting this heterogeneity. The aim was to develop an easy-to-use diagnostic strategy as a rational approach to the widening opportunities for the use of phenotype-targeted therapy. The guidelines were presented on websites for public comments by members of both the societies. The reviewers' comments contributed to creating the final version of the guidelines. The key hallmark of the diagnostic approach is the pragmatic concept, which assesses the presence of allergy and eosinophilia in each asthmatic patient. The guidelines define three clinically relevant asthma phenotypes: eosinophilic allergic asthma, eosinophilic nonallergic asthma and noneosinophilic nonallergic asthma. The resulting multifunctional classification describing the severity, level of control and phenotype is the starting point for a comprehensive treatment strategy. The level of control is constantly confronted with the intensity of the common stepwise pharmacotherapy, and the concurrently included phenotyping is essential for phenotype-specific therapy. The concept of the asthma approach with assessing the presence of eosinophilia and allergy provides a way for more precise diagnosis, which is a prerequisite for using widening options of personalized therapy.

IL-25-induced activation of nasal fibroblast and its association with the remodeling of chronic rhinosinusitis with nasal polyposis

Background and objective

Interleukin (IL)-25 has been shown to play an important role in the pathogenesis of chronic rhinosinusitis with nasal polyps. Nasal polyps are associated with chronic inflammation of the mucous membranes in the paranasal sinuses and are involved in extracellular matrix (ECM) accumulation. The aim of this study is to evaluate the effects of IL-25 on myofibroblast differentiation, ECM production and the expression of matrix metalloproteinases in nasal polyp derived fibroblasts (NPDFs) and to determine the molecular mechanism underlying these processes.

Materials and methods

A total of 40 patients were enrolled in this study for Immunofluorescence studies. Expression of IL17 receptor B was evaluated by real time reverse transcription polymerase chain reaction (PCR) in NPDFs. NPDFs were stimulated with IL-25 for 48 h in the presence or absence of mitogen-activated protein kinase (MAPK) and NF-κB inhibitors or small interfering RNAs (siRNA). The protein levels of fibrosis active mediators were examined using western blotting. Fibroblast migration was evaluated with a scratch assay. The total collagen amount was analyzed with the Sircol collagen assay.

Results

IL-25 induced α-SMA, fibronectin, and MMP-1 and -13, which were dependent on IL-17RB. IL-25 also induced activation of NF-κB and mitogen-activated protein kinase (MAPKs). By using the specific inhibitor of ERK, p38, JNK and NF-κB (U, SB, SP and Bay), we found that IL-25-induced expressions of α-SMA, fibronectin, and MMPs was regulated by the signaling pathways of MAPKs and NF-κB. IL-25 also induces α-SMA, fibronectin, and MMPs expression through IL-17RB-dependent pathways in NPDFs. The increased migration ability induced by IL-25 was suppressed by the specific inhibitors of MAPKs and NF-κB.

Conclusion

Our data indicate that IL-25 induced myofibroblast differentiation, fibronectin production, and MMP-1 and -13 expressions through the signaling pathways of MAPKs and NF-κB. in NPDFs and increased expression of IL-25 were also involved in the pathogenesis of nasal polyposis by affecting nasal fibroblasts in chronic rhinosinusitis with nasal polyps.

The Triple Aim and its implications on the management of chronic rhinosinusitis

INTRODUCTION

Accountable care organizations (ACO) and alternative payment models are a sign of the change in reimbursement from fee-for-service to value-based reimbursement. The focus of health care under ACOs is represented by the Triple Aim: to improve the experience of health care, improve the health of populations, and reduce the per capita costs. Individuals with chronic rhinosinusitis (CRS) are heavy consumers of health care services. Results of recent studies have indicated that there is the potential for improved outcomes and cost savings from early surgical intervention. Adhering to the principles of the Triple Aim may signal a paradigm shift in regard to timing of intervention for CRS in certain patients.

METHODS

A scoping review was performed to analyze the current literature related to management of CRS and the impact on cost, population health outcomes, and the patient's experience of health care.

RESULTS

A growing body of literature indicates that, in appropriately selected patients, when compared with medical management, endoscopic sinus surgery has the potential to improve patient outcomes and reduce the long-term cost burden of CRS.

CONCLUSION

With the advent of ACOs, a paradigm shift in the treatment of CRS is inevitable to better conform to the goals of the Triple Aim. Future treatment algorithms will need to account for the heterogeneity within CRS and seek to identify appropriate timing and interventions for patients on an individual basis if the value of health care is to be improved.

Radiographic Changes of the Nasal Septal Body Among Patients With Sinonasal Diseases

OBJECTIVES

This study aims to determine the anatomical changes occurring in the nasal septal body (NSB) among patients with sinonasal disease and compares the measurements obtained from patients without sinonasal disease.

METHODS

This was a retrospective study involving review of 405 (93 without and 212 with sinonasal disease) plain paranasal sinus computed tomography (PNS CT) on coronal view at a tertiary training hospital, which was done consecutively from January 2014 to December 2015. NSB measurements from 3 areas were done: anterior part (A), located anterior and superior to inferior turbinate; middle or widest (M) part, located anterior to middle turbinate and superior to inferior turbinate and posterior (P) part, located within the anterior 1/3 of middle turbinate not going beyond the crista galli. Posterior part of septum (sP) was measured at the area of horizontal attachment of middle turbinate to the lateral nasal wall and superior turbinate to represent the less vasoactive part of the septum. Demographic data and NSB diameters were also analyzed.

RESULTS

The mean NSB diameter measurements were significantly larger among the diseased group (disease vs. control; A: 6.88 mm vs. 5.92 mm, P=0.001; M: 12.74 mm vs. 10.47 mm, P=0.001; P: 8.35 mm vs. 6.79 mm, P=0.001). A similar observation in sP part (3.35 mm vs. 2.54 mm, P=0.014) was noted. When grouped by age, among the control group, older subjects had considerable decrease in NSB size in all points of measurements except for sP (P>0.05). Such reduction in size is noticeable for those in their 4th, 5th, 6th, and 7th decades of life. For the diseased group, a trend of increasing NSB and sP size was noted as the subjects are getting older. However, only the anterior part (A) of NSB reached statistical significance (P=0.016).

CONCLUSION

With aging we expect nasal mucosal atrophy among normal subjects. However, patients with chronic sinonasal disease showed thickened nasal mucosa. Further study for the reversibility of thickened mucosa is needed.

A Study of Single Nucleotide Polymorphisms of Tumour Necrosis Factor α-1031 And Tumour Necrosis Factor β+ 252 in Chronic Rhinosinusitis

OBJECTIVES

This case-controlled study aimed to identify the association of tumor necrosis factor (TNF)α-1031 and TNFβ+ 252 gene polymorphisms between chronic rhinosinusitis (CRS) and healthy controls. Another purpose of this study was to investigate the associations of these gene polymorphisms with factors related to CRS.

METHODS

All deoxyribonucleic acid (DNA) samples were genotyped for TNFα-1031 and TNFβ+252 genes by mean of polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLP). The statistical analysis were carried out using chi-square test or Fisher exact test to determine the associations of these gene polymorphisms in CRS. Multiple logistic regression was performed to evaluate the associations of these gene polymorphisms in CRS and its related risk factors.

RESULTS

The genotype and allele frequencies of TNFα-1031 and TNFβ+252 gene did not show any significant associations between CRS and healthy controls. However, a significantly statistical difference of TNFα-1031 was observed in CRS participants with atopy (P-value, 0.045; odds ratio, 3.66) but not in CRS with asthma or aspirin intolerance.

CONCLUSION

Although the presence of TNFα-1031 and TNFβ+252 gene polymorphisms did not render any significant associations between CRS and healthy control, this study suggests that TNFα-1031 gene polymorphisms in CRS patients with atopy may be associated with increase susceptibility towards CRS.

Thrombin and activated coagulation factor X stimulate the release of cytokines and fibronectin from nasal polyp fibroblasts via protease-activated receptors

BACKGROUND

Nasal epithelial cells and infiltrating eosinophils express tissue factor, and high thrombin activity and excess fibrin deposition are found in nasal secretion and in nasal polyp from patients with chronic rhinosinusitis with nasal polyp (CRSwNP). Activated coagulation factors play important roles not only in thrombosis but also in inflammation through interaction with protease-activated receptors (PAR). However, little is known about the effects of activated coagulation factors on the release of cytokines and extracellular matrix from nasal polyp fibroblasts (NPF).

PURPOSE

The purpose of this study was to analyze the expression of PARs, which are receptors for activated coagulation factors, on NPFs and to determine the roles of thrombin and activated coagulation factor X (FXa) in the release of cytokines and fibronectin from NPFs.

METHODS

NPFs were obtained from patients with CRSwNP, and the messenger RNA (mRNA) and protein expression of PARs in these NPFs were examined. We then investigated whether thrombin or FXa stimulates the release of transforming growth factor (TGF) beta 1, fibronectin, eotaxin-1, interleukin (IL) 6, or IL-8 from cultured NPFs. The effects of PAR agonists on the release of cytokines and fibronectin were also examined.

RESULTS

NPFs expressed the mRNA and proteins of all four PARs: PAR-1, PAR-2, PAR-3, and PAR-4. Both thrombin and FXa significantly stimulated the release of TGF beta 1, fibronectin, eotaxin-1, IL-6, and IL-8 from cultured NPFs. PAR-1 and PAR-2 agonists stimulated the secretion of TGF beta 1, fibronectin, eotaxin-1, IL-6, and IL-8. PAR-3 agonist stimulated the release of TGF beta 1, fibronectin, and eotaxin-1. PAR-4 agonist did not induce the release of these molecules.

CONCLUSION

NPFs play important roles in the pathophysiology of CRSwNP such as in nasal polyp formation and inflammatory cell infiltration by releasing cytokines and extracellular matrix proteins. Activated coagulation factors, thrombin and FXa, stimulate the release of these cytokines and fibronectin from NPFs via PARs.

Association of Inflammatory Status and Maxillary Sinus Schneiderian Membrane Thickness

OBJECTIVES

Certain Schneiderian membrane thicknesses (SMT) have shown to be more prone to tearing/perforation, and some pathologies might influence SMT. Henceforth, we aimed at studying the correlation of inflammatory status to SMT in human fresh cadaver heads.

MATERIAL AND METHODS

A total of 14 fresh cadaver heads including 27 Schneiderian membrane specimens were histologically collected. A 10-item inflammatory score was determined in the entire sample and also in the thinner and thicker areas of each sample. Data was analyzed by using the Wilcoxon rank test and the Spearman's rank correlation.

RESULTS

The mean measured SMT was 0.40 ± 0.12 mm and the median was 0.33 ± 0.12 mm. A weak positive correlation was found between the mean SMT and inflammation score without a statistical significance. (r = 0.385, p = 0.115). The Wilcoxon signed-rank test showed a statistical difference between the medians of the thinner and thicker areas (p < 0.001). The mean inflammation score of the thinner and thicker areas was 8.55 ± 2.57 and 11.61 ± 2.65, respectively. A moderate positive and statistically significant correlation was found between the inflammation score and the thickness of the thinner and thicker areas (r = 0.638, p = 0.000).

CONCLUSION

A moderate association between the Schneiderian membrane thickness and the level of inflammation exists.

Bacterial Pathogens and the Microbiome

Bacterial pathogens and microbiome alterations can contribute to the initiation and propagation of mucosal inflammation in chronic rhinosinusitis (CRS). In this article, the authors review the clinical and research implications of key pathogens, discuss the role of the microbiome, and connect bacteria to mechanisms of mucosal immunity relevant in CRS.

Significance of Blood Eosinophil Count in Patients with Chronic Rhinosinusitis with Nasal Polyposis

INTRODUCTION

Chronic Rhino Sinusitis (CRS) is one of the most prevalent chronic illnesses across the globe, affecting persons of all ages. It is an inflammatory process that involves the paranasal sinuses with symptoms lasting longer than 12 weeks.

AIM

To establish the significance of blood eosinophil (count) levels in CRS with nasal polyps and to compare blood eosinophil count with eosinophil count in the histopathology specimens of the polyps.

MATERIALS AND METHODS

This was a retrospective study done to review the medical records of 63 patients who underwent endoscopic sinus surgery for CRS with Nasal polyps. The patients were divided into two groups, 1 and 2 based on the number of patients suffering from non eosinophilic rhino sinusitis (Group 1) and those from eosinophlic rhino sinusitis (Group 2). The clinical examination findings, nasal endoscopy observations and MDCT-Paranasal sinuses were notified. Also, the mean Eosinophil Count (EC), Absolute Eosinophil Count (AEC), and Histopathology Eosinophil Count (HPE) was compared between two groups. This was aided by CT Scan Lund Mackay Scores (LMS).

RESULTS

Among the patients from Group 1, the male to female ratio was found to be 1.14:1 with 53.3% males and in Group 2 the same were noted as 1.75:1 and 63.6% respectively and found a male preponderance. With regard to symptomatology, significantly higher number of patients in the Group 2 suffered from nasal block (97% vs. 46.7%; p<0.001), nasal obstruction (90.9% vs. 46.7%; p<0.001), nasal discharge (81.8% vs. 56.7%; p=0.030), hyposmia (97% vs. 30%; p<0.001) and asthma (69.7% vs. 3.3%; p<0.001). However, facial pain (66.7% vs. 81.8%; p=0.168) and para nasal sinus tenderness (53.3% vs. 54.6%; p=0.923) were comparable in Groups 1 and 2. Mean EC, AEC and HPE were significantly high in Group 2 compared to Group 1.

CONCLUSION

The study demonstrated that there was a significant correlation between tissue and blood eosinophil counts with increased severity of symptoms in patients with Eosinophilic CRS with nasal polyps in the Indian population.

Nasal Polyp-Derived Mesenchymal Stromal Cells Exhibit Lack of Immune-Associated Molecules and High Levels of Stem/Progenitor Cells Markers

Mesenchymal stromal cells (MSCs) are considered adult progenitor stem cells and have been studied in a multitude of tissues. In this context, the microenvironment of nasal polyp tissue has several inflammatory cells, but their stroma compartment remains little elucidated. Hence, we isolated MSCs from nasal polyps Polyp-MSCs (PO-MSCs) and compared their molecular features and gene expression pattern with bone marrow-derived MSCs (BM-MSCs). Initially, both PO-MSCs and BM-MSCs were isolated, cultivated, and submitted to morphologic, differentiation, phenotypic, immunosuppressive, and gene expression assays. Compared to BM-MSCs, PO-MSCs showed normal morphology and similar osteogenic/adipogenic differentiation potential, but their immunophenotyping showed lack of immune-associated molecules (e.g., CD117, HLA-DR, PDL-1, and PDL-2), which was linked with less immunoregulatory abilities such as (i) inhibition of lymphocytes proliferation and (ii) regulatory T cell expansion. Furthermore, we detected in the PO-MSCs a distinct gene expression profile in comparison with BM-MSCs. PO-MSC expressed higher levels of progenitor stem cells specific markers (e.g., CD133 and ABCB1), while BM-MSCs showed elevated expression of cytokines and growth factors (e.g., FGF10, KDR, and GDF6). The gene ontology analysis showed that the differentially modulated genes in PO-MSC were related with matrix remodeling process and hexose and glucose transport. For BM-MSCs, the highly expressed genes were associated with behavior, angiogenesis, blood vessel morphogenesis, cell–cell signaling, and regulation of response to external stimulus. Thus, these results suggest that PO-MSCs, while sharing similar aspects with BM-MSCs, express a different profile of molecules, which presumably can be implicated in the development of nasal polyp tissue.

Tissue factor and tissue factor pathway inhibitor in nasal mucosa and nasal secretions of chronic rhinosinusitis with nasal polyp

BACKGROUND

Activation of the coagulation system with an increase in thrombin generation is involved in the pathogenesis of tissue remodeling in chronic rhinosinusitis (CRS). Tissue factor (TF) is an important protein for initiation of the extrinsic coagulation pathway, and TF pathway inhibitor (TFPI) is a regulator of TF-induced coagulation. This study was conducted to elucidate the roles of TF and TFPI in the pathogenesis of CRS.

METHODS

Tissue localization of TF, TFPI, and fibrin was determined by immunostaining of nasal polyps and inferior turbinates obtained during endonasal surgery in patients with CRS with nasal polyp (CRSwNP). Nasal secretions were collected from patients with CRSwNP, allergic rhinitis, and from control patients. The concentrations of TF and TFPI were measured in nasal secretions from each group. The concentrations of TF and TFPI released into culture medium by normal human nasal epithelial cells treated with thrombin, protease-activated receptor 1 agonist peptide, or tumor necrosis factor α were also measured.

RESULTS

TF expression was localized in nasal epithelial cells and in infiltrating eosinophils of nasal mucosa. TFPI expression was localized in nasal epithelial cells, and fibrin deposition was observed in nasal secretions and the lamina propria of nasal polyps. Nasal secretions contained significant concentrations of TF and TFPI. The concentration of TFPI in nasal secretions correlated positively with thrombin activity and the concentration of thrombin-antithrombin III complex. Treatment with thrombin, protease-activated receptor 1 agonist peptide, or tumor necrosis factor α stimulated significant release of TF and TFPI from cultured nasal epithelial cells.

CONCLUSIONS

By upregulating the coagulation system, TF and TFPI play an important role in the pathogenesis of CRSwNP.

Effect of eosinophils activated with Alternaria on the production of extracellular matrix from nasal fibroblasts

BACKGROUND

Eosinophils and fibroblasts are known to play major roles in the pathogenesis of nasal polyps. Fungi are commonly found in nasal secretion and are associated with airway inflammation.

OBJECTIVE

To investigate whether activated eosinophils by airborne fungi can influence the production of extracellular matrix (ECM) from nasal fibroblasts.

METHODS

Inferior turbinate and nasal polyp fibroblasts were stimulated with Alternaria or Aspergillus, respectively, for 24 hours and ECM messenger RNA (mRNA) and protein expressions were measured. Eosinophils isolated from healthy volunteers were stimulated with Alternaria or Aspergillus for 4 hours then superoxide, eosinophil peroxidase, and transforming growth factor β1 were measured. Then activated eosinophils were cocultured with nasal fibroblasts for 24 hours, and ECM mRNA expressions were measured.

RESULTS

Alternaria strongly enhanced ECM mRNA expression and protein production from nasal fibroblasts. Alternaria also induced the production of superoxide, eosinophil peroxidase, and transforming growth factor β1 from eosinophils, and activated eosinophils enhanced ECM mRNA expression when they were cocultured without the Transwell insert system.

CONCLUSION

Eosinophils activated with Alternaria enhanced ECM mRNA expression from nasal polyp fibroblasts. Alternaria plays an important role in tissue fibrosis in the pathogenesis of nasal polyps by directly or indirectly influencing the production of ECM from nasal fibroblasts.

Non-infectious Inflammatory Lesions of the Sinonasal Tract

This review covers the histopathology and pathogenesis of non-infectious inflammatory diseases of the sinonasal tract, in particular, sarcoidosis, granulomatous vasculitides Wegener, Churg-Strauss), relapsing polychondritis, eosinophilic angiocentric fibrosis, chronic rhinosinusitis and nasal perforations. Molecular associations and mechanisms are emphasised to assist pathologists to put their observations into the context of clinical, genetic and environmental influences on patients' diseases.