Interleukin 5, IL6, IL12, IFN-gamma, RANTES and Fractalkine in human nasal polyps, turbinate mucosa and serum

Oncostatin M Contributes to Airway Epithelial Cell Dysfunction in Chronic Rhinosinusitis with Nasal Polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a typical type-2 inflammation involving several cytokines and is associated with epithelial cell dysfunction. Oncostatin M (OSM) (belonging to the interleukin(IL)-6 family) could be a key driver of epithelial barrier dysfunction. Therefore, we investigated the presence of OSM and IL-6 and the expression pattern of tight junctions (TJs) in the nasal tissue of CRSwNP patients and controls using reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and Western blotting. Then, their potential role in the epithelial barrier was evaluated in vitro in 27 different primary cultures of human nasal epithelial cells (HNECs) by measuring TJ expression and transepithelial electric resistance (TEER) with or without OSM or IL-6 (1, 10, and 100 ng/mL). The effect on ciliary beating efficiency was evaluated by high-speed videomicroscopy and on repair mechanisms with a wound healing model with or without OSM. OSM and IL-6 were both overexpressed, and TJ (ZO-1 and occludin) expression was decreased in the nasal polyps compared to the control mucosa. OSM (100 ng/mL) but not IL-6 induced a significant decrease in TJ expression, TEER, and ciliary beating efficiency in HNECs. After 24 h, the wound repair rate was significantly higher in OSM-stimulated HNECs at 100 ng/mL. These results suggest that OSM could become a new target for monoclonal antibodies.

Schlenter W, Welkoborsky HJ, Wollenberg B, Bergmann C, Cuevas M, Beutner C, Gröger M, Becker S. Dokumentation von Biologika-Therapien bei chronischer Rhinosinusitis mit Polyposis nasi (CRSwNP): Dupilumab, Omalizumab und Mepolizumab

Hintergrund: Die chronische Rhinosinusitis mit Nasenpolypen (CRSwNP) ist eine multifaktorielle entzündliche Erkrankung der paranasalen Schleimhäute, der als Endotyp meistens eine Typ-2-Inflammation zugrunde liegt. Mittlerweile sind drei Antikörper (Dupilumab, Omalizumab und Mepolizumab) für die Therapie der schweren CRSwNP zugelassen. Eine Dokumentation der Erkrankungsschwere im Behandlungsverlauf ist unverzichtbar.

Methoden: In einer Literaturrecherche in Medline, Pubmed sowie den nationalen und internationalen Studien- und Leitlinienregistern und der Cochrane Library wurde die Immunologie der CRSwNP analysiert und die Evidenz zur Wirkung von Dupilumab, Omalizumab und Mepolizumab bei dieser Erkrankung ermittelt. Hieraus wurden drei Positionspapiere durch unsere Autorengruppe erstellt, die Grundlage dieser zusammenfassenden Übersichtsarbeit sind.

Ergebnisse: Basierend auf den Angaben aus der internationalen Literatur werden von einem Expertengremium Empfehlungen für die Anwendung von Dupilumab, Omalizumab und Mepolizumab bei CRSwNP im deutschen Gesundheitssystem gegeben.

Schlussfolgerung: Dupilumab, Omalizumab und Mepolizumab sind zugelassen für Patienten ab 18 Jahren mit schwerer CRSwNP als Zusatztherapie zu intranasalen Glukokortikosteroiden (INCS), wenn, bei Dupilumab und Mepolizumab, durch eine Therapie mit systemischen Glukokortikosteroiden und/oder chirurgischem Eingriff keine ausreichende Krankheitskontrolle erzielt werden kann. Eine Therapie mit Omalizumab ist angezeigt, wenn eine Therapie mit INCS keine suffiziente Kontrolle der Erkrankung ergibt. Es werden dezidierte Empfehlungen zur Dokumentation der Anwendung im Deutschen Gesundheitssystem gegeben, die auf den hierzu bereits publizierten Positionspapieren unserer Autorengruppe basieren.

Zitierweise: Klimek L, Förster-Ruhrmann U, Beule AG, Chaker AM, Hagemann J, Klimek F, Casper I, Huppertz T, Hoffmann TK, Dazert S, Deitmer T, Olze H, Strieth S, Wrede H, Schlenter W, Welkoborsky H-J, Wollenberg B, Bergmann C, Cuevas M, Beutner C, Gröger M, Becker S. Indicating biologics for chronic rhinosinusitis with nasal polyps (CRSwNP): Recommendations by German Allergy and ORL-societies AeDA and DGHNO for Dupilumab, Omalizumab and Mepolizumab. Allergo J Int 2022;31:149-60

https://doi.org/10.1007/s40629-022-00220-x

Cytokine Signature and Involvement in Chronic Rhinosinusitis with Nasal Polyps

Cytokines are well known to play a central role in chronic rhinosinusitis with nasal polyps (CRSwNP), particularly in maintenance of the inflammatory response and the recruitment of eosinophils. The pathophysiological concepts concerning the involvement of inflammatory cytokines in CRSwNP have gradually evolved. Although the Th2 cytokines environment associated with an eosinophilic infiltration has retained a central role in the genesis of polyps, the role of other cytokine subpopulations has also and more recently been detailed, leading to a specific and complex signature in CRSwNP. The purpose of this review is to summarize the current state of knowledge about the cytokine signature in CRSwNP, the role of cytokines in the pathogenesis of this disease and in the intercellular dialog between epithelial cells, fibroblasts and inflammatory cells. Knowledge of this precise cytokine signature in CRSwNP is fundamental in the perspective of potential targeting biotherapies.

Positionspapier: Empfehlungen zur Anwendung von Omalizumab bei chronischer Rhinosinusitis mit Polyposis nasi (CRSwNP) im deutschen Gesundheitssystem – Empfehlungen des Ärzteverbandes Deutscher Allergologen (AeDA) und der AGs Klinische Immunologie, Allergologie und Umweltmedizin und Rhinologie und Rhinochirurgie der Deutschen Gesellschaft für HNO-Heilkunde, Kopf- und Halschirurgie (DGHNOKHC)

Hintergrund Die chronische Rhinosinusitis mit Nasenpolypen (CRSwNP) ist eine multifaktorielle entzündliche Erkrankung der paranasalen Schleimhäute, der als Endotyp meistens eine TH2-Inflammation zugrunde liegt. IgE-Antikörper spielen dabei eine wichtige Rolle. Der anti-IgE-Antikörper Omalizumab wurde im August 2020 für die Therapie der schweren CRSwNP zugelassen.

Methoden In einer Literatursuche wurde die Immunologie der CRSwNP analysiert und die Evidenz zur Wirkung von Omalizumab bei dieser Erkrankung ermittelt durch Recherchen in Medline, Pubmed sowie den nationalen und internationalen Studien- und Leitlinien-Registern und der Cochrane Library.

Ergebnisse Basierend auf diesen Angaben aus der internationalen Literatur werden von einem Expertengremium Empfehlungen für die Anwendung von Omalizumab bei CRSwNP im deutschen Gesundheitssystem gegeben.

Schlussfolgerung Omalizumab ist zugelassen für Patienten ab 18 Jahren mit schwerer chronischer Rhinosinusitis mit Nasenpolypen als Zusatztherapie zu intranasalen Kortikosteroiden (INCS), wenn durch eine Therapie mit INCS keine ausreichende Krankheitskontrolle erzielt werden kann.

Interaction Between Serum/Glucocorticoid-Regulated Kinase 1 and Interleukin-6 in Chronic Rhinosinusitis

PURPOSE

Serum/glucocorticoid-regulated kinase 1 (SGK1) has recently emerged as a critical regulator of inflammatory diseases. In this study, we examined SGK1 expression and its possible pathogenic roles in chronic rhinosinusitis (CRS).

METHODS

Immunohistochemistry, western blotting, Bio-Plex assay, enzyme-linked immunosorbent assays, and quantitative real-time polymerase chain reaction were performed to assess protein and gene expression levels. The mRNA expression levels of SGK1 and interleukin-6 (IL-6) were extracted from a CRS database to perform correlation analysis. Stable cell lines with SGK1 overexpression (16HBE) and knockdown (A549) were constructed to investigate the interaction between SGK1 and IL-6 in vitro.

RESULTS

SGK1 exhibited strong cytoplasmic and nuclear staining in the epithelial layers and the lamina propria of nasal polyps (NPs) and in the mucosal tissues of CRS without nasal polyps (CRSsNP). The mRNA and protein expression levels of SGK1 and IL-6 were significantly increased in NPs and CRSsNP tissues, compared to control tissues. SGK1 phosphorylation was significantly greater in NPs than in CRSsNP tissues (P < 0.01). The mRNA levels of SGK1 and IL-6 were significantly correlated (P < 0.001, r = 0.649). Exposure to IL-6 significantly increased SGK1 expression in cultured dispersed NP cells, 16HBE cells, and A549 cells. IL-6 expression was significantly down-regulated in SGK1-overexpressing 16HBE cells (P < 0.01) and significantly up-regulated in SGK1-knockdown A549 cells (P < 0.05). Administration of GSK650394, a SGK1 inhibitor, significantly increased IL-6 self-induced mRNA expression in cultured dispersed NP cells and 16HBE cells.

CONCLUSIONS

The interaction between SGK1 and IL-6 may play an anti-inflammatory role in IL-6-induced inflammation in the pathogenesis of CRS.

Interferon-α action in cytokine profile in eosinophilic nasal polyp cultures

INTRODUCTION

Chronic rhinosinusitis is currently classified into two types: chronic rhinosinusitis without nasal polyps and chronic rhinosinusitis with nasal polyps. In the West, approximately 80% of chronic rhinosinusitis with nasal polyps cases are characterized by a predominantly eosinophilic cell infiltrate and a Th2 cytokine pattern.

OBJECTIVE

To evaluate the effect of Interferon-α on cytokine levels of the eosinophilic nasal polyp cell culture supernatant.

METHODS

Cell cultures were performed based on nasal polypoid tissue samples collected from 13 patients with eosinophilic chronic rhinosinusitis with nasal polyps. Polyps were considered eosinophilic according to the histopathological examination. Cell cultures were stimulated with 3000 IU of interferon-α. Before and after the stimulus, concentrations of Interferon-γ, tumor necrosis factor αand IL 2, 4, 6 and 10, using cytometric bead array, were assessed.

RESULTS

Cell samples from eosinophilic nasal polyps from 13 patients were included in the study. Twenty-four hours after interferon-α stimulation, eosinophilic nasal polyp culture supernatants showed significantly decreased IL-4 concentrations and increase in interferon-γ, IL-10 and IL-6 concentrations compared to controls. There were no significant differences in tumor necrosis factor -α and IL-2 concentrations.

CONCLUSION

We demonstrated that interferon-α in vitro alters the pattern of cytokines in cell cultures of eosinophilic nasal polyps. Analysis of these alterations suggests that interferon-α promotes a rebalancing of inflammatory profiles in cell cultures, favoring the expression of Th1 and regulatory cytokines over Th2 cytokines.

Biotherapy and treatment of adult primary chronic rhinosinusitis with nasal polyps: Cellular and molecular bases

The present article reviews the molecular and cellular mechanisms involved in the pathophysiology of chronic rhinosinusitis with nasal polyps (CRSwCRSwNP) and underlying the action mechanisms of biotherapies. Biotherapy uses substances naturally produced by the organism or their specific antagonists targeting a proinflammatory mechanism. CRSwCRSwNP is a form of chronic rhinosinusitis (CRS), which is classically subdivided in to 2 types according to the presence of polyps. In recent years, the concept of endotypes emerged, with a more exhaustive definition of the types of CRS according to inflammatory mechanism, with a view to developing personalized treatments. CRSwNP pathophysiology is poorly understood. Polyps arise from a primary epithelial lesion in a context of chronic local inflammation, mainly type 2 in Europe, implicating eosinophils, IgE, Th2 cytokines (IL-4/IL-13, IL-5) and T and B cells. Biotherapy seems promising in CRSwNP. The present review details the various pathophysiological pathways underlying the action mechanisms of biotherapies, and the various published studies, assessing efficacy and mode of action in the treatment of CRSwNP.

Pathogenesis of chronic rhinosinusitis with nasal polyps: role of IL-6 in airway epithelial cell dysfunction

Background

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by an alteration in airway epithelial cell functions including barrier function, wound repair mechanisms, mucociliary clearance. The mechanisms leading to epithelial cell dysfunction in nasal polyps (NPs) remain poorly understood. Our hypothesis was that among the inflammatory cytokines involved in NPs, IL-6 could alter epithelial repair mechanisms and mucociliary clearance. The aim of this study was to evaluate the in vitro effects of IL-6 on epithelial repair mechanisms in a wound repair model and on ciliary beating in primary cultures of Human Nasal Epithelial Cells (HNEC).

Methods

Primary cultures of HNEC taken from 38 patients during surgical procedures for CRSwNP were used in an in vitro model of wound healing. Effects of increasing concentrations of IL-6 (1 ng/mL, 10 ng/mL, and 100 ng/mL) and other ILs (IL-5, IL-9, IL-10) on wound closure kinetics were compared to cultures without IL-modulation. After wound closure, the differentiation process was characterized under basal conditions and after IL supplementation using cytokeratin-14, MUC5AC, and β_IV tubulin as immunomarkers of basal, mucus, and ciliated cells, respectively. The ciliated edges of primary cultures were analyzed on IL-6 modulation by digital high-speed video-microscopy to measure: ciliary beating frequency (CBF), ciliary length, relative ciliary density, metachronal wavelength and the ciliary beating efficiency index.

Results

Our results showed that: (i) IL-6 accelerated airway wound repair in vitro, with a dose–response effect whereas no effect was observed after other ILs-stimulation. After 24 h, 79% of wounded wells with IL6-100 were fully repaired, vs 46% in the IL6-10 group, 28% in the IL6-1 group and 15% in the control group; (ii) specific migration analyses of closed wound at late repair stage (Day 12) showed IL-6 had the highest migration compared with other ILs (iii) The study of the IL-6 effect on ciliary function showed that CBF and metachronal wave increased but without significant modifications of ciliary density, length of cilia and efficiency index.

Conclusion

The up-regulated epithelial cell proliferation observed in polyps could be induced by IL-6 in the case of prior epithelial damage. IL-6 could be a major cytokine in NP physiopathology.

Topical Vitamin D May Modulate Human Sinonasal Mucosal Responses to House Dust Mite Antigen

BACKGROUND

Respiratory epithelium is a key defense against inhaled pathogens. Vitamin D3 (VD) has been suggested to modulate airway inflammation; however, its effect on innate airway defenses, the physical barrier, mucociliary apparatus, and cytokine release remains unclear.

OBJECTIVE

To investigate the outcomes of VD application prior to challenge in an in vitro model of human sinonasal epithelium, through assessment of epithelial transepithelial resistance (TER), cilia beat frequency (CBF), and interleukin (IL)-6 release, and secondarily to determine whether topical VD is beneficial to patients with inflammatory sinonasal pathology.

METHODS

Primary human sinonasal epithelial cells from patients with eosinophilic chronic rhinosinusitis (eCRS) and healthy controls were cultured in air-liquid interface (ALI). Well-differentiated cultures from each patient were pretreated for 24 hours with 4 different VD doses. Toxicity was quantified at 24 hours in unchallenged ALI by lactate dehydrogenase (LDH) assay. Innate responses were assessed by measuring TER and CBF before and up to 24 hours after house dust mite Dermatophagoides pteronyssinus challenge. IL-6 release was evaluated 24-hour postchallenge.

RESULTS

Fifteen patients (53 ± 13.5 years, 60% females, 53% eCRS) representing 120 ALI wells were assessed. VD (0, 25, 50, 150 IU/mL) released less LDH than vehicle, indicating noncytotoxicity (0.15 ± 0.02; 0.15 ± 0.00; 0.14 ± 0.02; 0.11 ± 0.01 vs 0.17 ± 0.03, P = .004). VD increased TER for eCRS wells at 5 minutes (50 IU/mL: Δ6.76 ± 3.93 vs Δ3.87 ± 2.46, P = .04) and 24 hours (50 IU/mL: Δ0.88 ± 0.49 vs Δ0.40 ± 0.42, P = .02; 150 IU/mL: Δ1.06 ± 0.58 vs Δ0.47 ± 0.46, P = .01). CBF increased at 1 hour for eCRS wells (50 IU/mL: Δ0.62 ± 0.14 vs Δ0.41 ± 0.13, P = .001; 150 IU/ml: Δ0.60 ± 0.13 vs Δ0.38 ± 0.11, P < .001). IL-6 release was similar between normal and eCRS wells.

CONCLUSION

Topical VD supplementation in eCRS patients may be beneficial for innate epithelial defenses. VD is noncytotoxic and does not adversely affect the physical barrier, mucociliary apparatus, or IL-6 release. Further studies should clarify its potential as a therapeutic agent.

[Immunology of chronic rhinosinusitis with nasal polyps as a basis for treatment with biologicals]

BACKGROUND

Chronic rhinosinusitis (CRS) is a heterogeneous and multifactorial inflammation of the nasal and paranasal mucosa. Until now, no internationally standardized classification could be developed. In most cases, CRS is phenotypically classified according to chronic rhinosinusitis with (CRScNP) and without nasal polyps (CRSsNP). However, recent studies could show that there are numerous endotypes within these phenotypes based on different inflammatory mechanisms. This review describes the important immunological mechanisms of CRScNP and highlights modern treatment options with biologicals directly addressing particular immunological processes.

METHODS

Current knowledge on immunological and molecular processes of CRS, particularly CRScNP, was extracted from Medline, PubMed, national and international study- and guideline-registers, and the Cochrane library by a systematic review of the literature.

RESULTS

Based on current literature, various immunological mechanisms for CRS and CRScNP could be identified. Relevant studies for the treatment of eosinophilic conditions such as asthma or CRScNP are presented and, if available, results of these studies are discussed.

CONCLUSION

The growing insight into the underlying immunological mechanisms of CRScNP could pave the way for new personalized treatment options such as biologicals in the future.

Inflammatory patterns of antrochoanal polyps in the pediatric age group

Background

The pathogenesis and etiology of antrochoanal polyps (ACPs) remains obscure. This study aimed to characterize the inflammatory profiles and investigate the effect of atopy on the pathogenesis of pediatric ACPs.

Methods

Thirty-three ACP patients and ten control subjects were enrolled from January to December 2017. The severity of individual nasal symptoms was scored on a visual analogue scale (VAS). The serum total immunoglobulin E (IgE) and cytokines level was measured by multiplexed luminex assay.

Results

There was no significant difference in VAS scores and counts of inflammatory cells between atopic and nonatopic ACP. No difference in IFNγ, IL-4, IL-5, IL-13, IL-17A and IL-25 was found between control and whole ACP, nonatopic and atopic ACP. Significantly increased levels of IL-6 and IL-10 were found in ACP compared with control. For neutrophil chemotactic factor, significant increases of IL-8 and GRO were observed in ACP, but for eosinophil chemotactic factor, no difference was found in RANTES and GM-CSF. IL-6 level was positively correlated with IL-8, MCP1, and GRO level, and IL-10 level was positively correlated with IL-4 and IL-13 in ACP subjects.

Conclusion

Nasal obstruction was the most common symptom in ACPs in children. Allergic condition may have a poor role in the pathogenesis of ACPs. IL-6 plays a crucial role in the pathogenesis of neutrophilic inflammation in patients with ACPs and may provide a new treatment strategy for ACPs in children. Treg cell associated cytokine IL-10 was involved in the inflammatory pathophysiological process of ACPs and played a certain regulatory role.

Investigating the correlation between mucus cytokine levels, inflammatory cell counts, and baseline quality-of-life measures in chronic rhinosinusitis

BACKGROUND

It is hypothesized that uncontrolled inflammation is responsible for many of the manifestations and symptoms of chronic rhinosinusitis (CRS). Although earlier work has demonstrated an association between olfactory loss and mucus cytokines, the impact on other symptoms is unknown. In this study we investigated the relationship between cytokines, inflammatory cell counts, and patient-reported outcomes measures to better understand how the inflammatory microenvironment correlates with CRS symptomatology.

METHODS

The 22-item Sino-Nasal Outcome Test (SNOT-22) and 8-item Short Form Health Survey (SF-8) were administered to 76 patients undergoing endoscopic sinus surgery for CRS. Mucus was collected intraoperatively from the middle meatus and tested for 17 cytokines using a multiplex flow cytometric bead assay. Eosinophil/neutrophil counts were obtained from histopathologic slide review. Spearman correlations between cytokines, cell counts, and quality-of-life subdomain scores were assessed without multiple comparisons correction due to the small sample size.

RESULTS

Interleukin-4 (IL-4) correlated significantly with the Rhinologic domain (R_s = 0.25, p = 0.03), whereas eosinophil and neutrophil counts were inversely correlated with the Extranasal Rhinologic domain (R_s = -0.32, p = 0.01; and R_s = -0.27, p = 0.03). Subgroup analysis for nasal polyposis (CRSwNP) showed significant correlations between IL-6 and Total SF-8 (R_s = 0.35, p = 0.02), General Health (R_s = 0.34, p = 0.03), and Emotional (R_s = 0.47, p = 0.002) scores. In patients without polyps (CRSsNP), IL-21 correlated positively with Extranasal Rhinologic Symptoms domain (R_s = 0.41, p = 0.01).

CONCLUSION

This pilot study identifies possible pairwise correlations between mucus cytokine levels and baseline quality-of-life measures that need confirmation in larger, targeted studies. Due to the exploratory methodology, positive results may be spurious and should only be used as a starting point for future confirmatory work.

Subtyping of polyposis nasi: phenotypes, endotypes and comorbidities

BACKGROUND

Chronic rhinosinusitis (CRS) is a heterogeneous, multifactorial inflammatory disease of the nasal and paranasal mucosa. It has not been possible to date to develop an internationally standardized, uniform classification for this disorder. A phenotype classification according to CRS with (CRSwNP) and without polyposis (CRSsNP) is usually made. However, a large number of studies have shown that there are also different endotypes of CRS within these phenotypes, with different pathophysiologies of chronic inflammation of the nasal mucosa. This review describes the central immunological processes in nasal polyps, as well as the impact of related diseases on the inflammatory profile of nasal polyps.

MATERIALS AND METHODS

The current knowledge on the immunological and molecular processes of CRS, in particular CRSwNP and its classification into specific endotypes, was put together by means of a structured literature search in Medline, PubMed, the national and international guideline registers, and the Cochrane Library.

RESULTS

Based on the current literature, the different immunological processes in CRS and nasal polyps were elaborated and a graphical representation in the form of an immunological network developed. In addition, different inflammatory profiles can be found in CRSwNP depending on related diseases, such as bronchial asthma, cystic fibrosis (CF), or NASID-Exacerbated Respiratory Disease (N‑ERD).

CONCLUSION

The identification of different endotypes of CRSwNP may help to improve diagnostics and develop novel individual treatment approaches in CRSwNP.

Phenotypic and functional characteristics of IL-21-expressing CD8(+) T cells in human nasal polyps

Although CD4⁺ T cells are recognized to play an important role in the inflammatory response of nasal polyps (NPs), the biological functions of CD8⁺ T cells in polypogenesis remain unclear. In this study, we analyzed cell markers, cytokine expression and transcription factors in IL-21-expressing CD8⁺ T cells in polyp tissues of NP patients. The results showed that the majority of IL-21-producing CD8⁺ T cells were effector memory cells and they co-expressed IFN-γ. IL-21-expressing CD8⁺ T cells in polyp tissues expressed higher CXCR5, PD-1, and ICOS levels than cells in control tissues and showed significantly higher T-bet and Bcl-6 expression levels compared with IL-21⁻CD8⁺ T cells. Purified polyp CD8⁺ T cells promoted IgG production from isolated polyp B cells in vitro, and recombinant IL-12 modulated the expression of IL-21, IFN-γ and CD40L in purified polyp CD8⁺ T cells. Moreover, the percentage of IL-21⁺CD8⁺ T cells in polyp tissues was positively correlated with endoscopic and CT scan scores in NP patients. These findings indicated that polyp CD8⁺ T cells, by co-expressing IL-21 and IFN-γ and other markers, display a Tfh cell functionality, which is associated with the clinical severity of NP patients.

Eosinophil-derived neurotoxin, elastase, and cytokine profile in effusion from eosinophilic otitis media

BACKGROUND

Eosinophilic otitis media (EOM) is an intractable disease characterized by a remarkably viscous effusion and accumulation of numerous eosinophils in both the middle ear effusion and the mucosa. The key factors in EOM pathogenesis remain unclear. The purpose of this study is to identify the important factors involved in EOM pathogenesis.

METHODS

Middle ear effusion samples were collected from 12 patients with EOM and 9 patients with secretory otitis media (SOM), as controls. Multiple cytokines in the effusion were measured using a Bio-Plex™ Human Cytokine 27-Plex panel. Eosinophil-derived neurotoxin (EDN) and elastase were measured by ELISA. The concentrations of EDN, elastase, and each cytokine were compared between the EOM and SOM groups. Furthermore, in the EOM group, each cytokine was examined for correlation with EDN and elastase.

RESULTS

EDN and elastase concentrations were significantly higher in the EOM group than in the SOM group (p < 0.05). IL-5, IL-1β, MIP-1α, G-CSF, IL-1ra, IL-4, IFN-γ, MIP-1β, IL-10, TNF-α, VEGF, and IL-2 concentration was significantly higher in the EOM group than in the SOM group (p < 0.05). Significant positive correlations were found between EDN and IL-1ra, IL-2, IL-5, IL-9, IL-13, eotaxin, MIP-1α, PDGF-BB, and RANTES in the EOM group (p < 0.05).

CONCLUSIONS

Our study showed that IL-5, IL-2, MIP-1α, and IL-1ra are the important factors involved in EOM pathogenesis. Furthermore, not only eosinophil, but also neutrophil are involved in middle ear inflammation of EOM.

Human IL-21+IFN-γ+CD4+ T cells in nasal polyps are regulated by IL-12

In the previous study, we found that the levels of IL-21 in nasal polyps (NPs) were significantly increased and associated with polyp size and recurrence. However, it is unclear that the cell source of IL-21 and the regulation of IL-21 in NP tissues. In the present study, we isolated the lymphocytes from NP tissues, uncinate tissues and peripheral blood of patients with NPs. The cells were analyzed for cell surface markers, cytokines and transcriptional factors by flow cytometry. The results indicated that CD4⁺ T cells were the major IL-21-exprssing cells in NP tissues and the majority of IL-21 producing CD4⁺ T cells co-expressed IFN-γ or IL-17A. IL-21⁺IFN-γ⁺CD4⁺ T cells in NP tissues exhibited the features of both Tfh and Th1 cells which co-expressed significantly higher amount of CXCR5, ICOS, PD-1, Bcl-6 and T-bet than did IL-21⁺IFN-γ⁻CD4⁺ T cells (p < 0.05). Treatment of the lymphocytes from NP tissues with IL-12 enhanced the production of IL-21 and IFN-γ, especially the frequency of IL-21⁺IFN⁻γ⁺CD4⁺ T cells (p < 0.05). The blockade of IL-12 inhibited the production of IL-21 and IFN-γ (p < 0.05). These findings indicated that IL-12 positively enhanced the generation of IL-21⁺IFN-γ⁺CD4⁺ T cells having the features of both Tfh and Th1 cells in NP tissues.

Cellular comparison of sinus mucosa vs polyp tissue from a single sinus cavity in chronic rhinosinusitis

BACKGROUND

Nasal polyposis is a common development in chronic rhinosinusitis (CRS), and sinus mucosa and polyp tissue have been used interchangeably in studies investigating CRS. However, potential differences may exist between these 2 tissue types, which have not been entirely characterized.

METHODS

A cross-sectional study of CRS with nasal polyposis (CRSwNP) patients undergoing endoscopic sinus surgery was conducted. Sinus mucosal biopsies and corresponding polyp tissue were obtained from the same sinus cavity via flow cytometry, single-cell suspensions identified type 2 innate lymphoid cells (ILC2s), CD4 and CD8 T cells, activated CD4 and CD8 T cells, plasma cells, plasmacytoid dendritic cells (pDCs), regulatory T cells, T follicular helper cells, B cells, and immunoglobulin A (IgA)(+) and IgG(+) B cells. Cells were measured as a percentage of CD45(+) cells. Paired nonparametric comparisons between sinus and polyp tissue were performed.

RESULTS

Ten patients (50% female; age 48 ± 16 years) were recruited. Significantly elevated ILC2 levels were found in polyp tissue compared to sinus mucosa (0.12 [0.07 to 0.23] vs 0.07 [0.04 to 0.16], p = 0.02), as well as plasma cells (2.25 [0.84 to 3.68] vs 1.18 [0.74 to 2.41], p = 0.01); pDCs (0.15 [0.12 to 0.50[ vs 0.04 [0.02 to 0.17], p = 0.03); activated CD8 T cells (29.22 [17.60 to 41.43] vs 16.32 [10.07 to 36.16], p = 0.04) and IgG(+) B cells (6.96 [0.06 to 11.82] vs 1.51 [0.38 to 5.13], p = 0.04). Other cell populations showed no significant differences.

CONCLUSION

Polyps have a similar cellular composition to that of mucosa. Higher levels of ILC2s, plasma cells, pDCs, activated CD8 T cells, and IgG(+) B cells in polyp tissue may be reflective of cell populations driving nasal polyp development. The cellular machinery of CRS is present in polyps and representative of the disease process. This pilot study strongly suggests that a larger study would provide significant insights into the relationship of sinus mucosa to pathogenesis of nasal polyps.

Prostaglandin E2 Induces IL-6 and IL-8 Production by the EP Receptors/Akt/NF-κB Pathways in Nasal Polyp-Derived Fibroblasts

Purpose

Interleukin 6 (IL-6) and IL-8 participate in the pathogenesis of chronic rhinosinusitis with nasal polyps, and their levels are increased by prostaglandin E2 (PGE2) in different cell types. The purposes of this study were to determine whether PGE2 has any effect on the increase in the levels of IL-6 and IL-8 in nasal polyp-derived fibroblasts (NPDFs) and subsequently investigate the possible mechanism of this effect.

Methods

Different concentrations of PGE2 were used to stimulate NPDFs at different time intervals. NPDFs were treated with agonists and antagonists of E prostanoid (EP) receptors. To determine the signaling pathway for the expression of PGE2-induced IL-6 and IL-8, PGE2 was treated with Akt and NF-κB inhibitors in NPDFs. Reverse transcription-polymerase chain reaction for IL-6 and IL-8 mRNAs was performed. IL-6 and IL-8 levels were measured byenzyme-linked immunosorbent assay (ELISA). The activation of Akt and NF-κB was evaluated by western blot analysis.

Results

PGE2 significantly increased the mRNA and protein expression levels of IL-6 and IL-8 in NPDFs. The EP2 and EP4 agonists and antagonists induced and inhibited IL-6 expression. However, the EP4 agonist and antagonist were only observed to induce and inhibit IL-8 expression level. The Akt and NF-κB inhibitors significantly blocked PGE2-induced expression of IL-6 and IL-8.

Conclusions

PGE2 increases IL-6 expression via EP2 and EP4 receptors, and IL-8 expression via the EP4 receptor in NPDFs. It also activates the Akt and NF-κB signal pathways for the production of IL-6 and IL-8 in NPDFs. These results suggest that signaling pathway for IL-6 and IL-8 expression induced by PGE2 might be a useful therapeutic target for the treatment of nasal polyposis.

Confounding factors in rhinological research

PURPOSE OF REVIEW

Basic science studies directed at understanding the inflammatory mechanisms in chronic rhinosinusitis (CRS) are increasing, yet their relevance to the underlying disease process is often conflicting and confounded by the enrollment of a heterogeneous CRS population. This review is aimed at exploring the issues affecting the basic science mucosal studies of CRS patients, with special attention to the inclusion criteria for CRS and the control group, and the site from which the mucosal tissue sample is obtained.

RECENT FINDINGS

A common confounding factor is an inadequate documentation of selection criteria for patients, controls, and tissue sites examined. Inconsistent definitions for CRS and for maximum medical therapy, and a lack of histopathology confirmation of mucosal inflammation (eosinophilic or neutrophilic) can bias the disease population entering a given study. Further confounding factors include the influence of coexisting diseases, pollution and cigarette smoke, and a need for same-site tissue comparisons, meticulous selection of relevant controls, and consensus on 'nondiseased' mucosal inflammatory cell populations and microbiology.

SUMMARY

Documentation of well defined patient and control groups, standardized specimen collection methods, and detection assays are critical in minimizing the bias and conflicting findings among investigators. With standardized sampling of tissue sites and tight controls on subcategories of CRS patients enrolled, studies will more likely identify the findings that can increase our understanding of the disparate group of CRS patients and identify new therapeutic targets in the CRS subcategories.

Novel cooperation between CX3CL1 and CCL26 inducing NK cell chemotaxis via CX3CR1: a possible mechanism for NK cell infiltration of the allergic nasal tissue

BACKGROUND

Recent data indicated that natural killer (NK) cells and chemokines could play a pivotal role in nasal inflammation. CX3CR1, the only receptor for fractalkine/CX3CL1, is abundantly expressed by NK cells, and was recently shown to also be a receptor for eotaxin-3/CCL26. However, no reports explored the NK cells-CX3CL1-CCL26 axis via CX3CR1 in allergy.

OBJECTIVE

Our goals were first to determine specifically NK cell recruitment pattern in nasal tissue of allergic chronic rhinosinusitis (ACRS) and non-allergic chronic rhinosinusitis (NACRS) patients in comparison with healthy controls, and secondly, to investigate the function of CX3CR1 in NK cell migration.

METHODS

Immunohistochemistry, microchemotaxis chambers, flow cytometry and confocal microscopy were used in this study.

RESULTS

Herein, we showed that NK cells infiltrated the epithelial layers of nasal tissue only in ACRS patients and not in NACRS patients or controls. NK cells were also more numerous in the stroma of the nasal tissue from ACRS patients compared with NACRS patients or controls. This migration could be mediated by both CX3CL1 and CCL26, as these two chemokines induced NK cell migration. Moreover, both molecules also stimulated cytoskeleton changes and F-actin reorganisation in NK cells. Chemotaxis and cytoskeleton changes were sensitive to genistein, a tyrosine kinase inhibitor. By flow cytometry, we demonstrated that a single antigen nasal provocation challenge increased the expression of CX3CR1 on NK cells in allergic rhinitis (AR) patients. The function of this receptor was associated with a significant augmentation of NK cell chemotaxis against the optimal doses of CX3CL1 and CCL26.

CONCLUSIONS AND CLINICAL RELEVANCE

Our results highlight a novel role for CX3CR1 in NK cell migration that may contribute to the NK cell trafficking to the allergic upper airway. This could be mediated largely by CX3CL1 and CCL26 stimulation of the tyrosine kinase pathway.

Expression of RANTES, eotaxin-2, ICAM-1, LFA-1 and CCR-3 in chronic rhinosinusitis patients with nasal polyposis

PURPOSE

To compare gene expression of the chemokines RANTES and eotaxin-2, its receptor, CCR-3, adhesion molecule ICAM-1 and its receptor LFA-1 in eosinophilic polyps and in control normal nasal mucosa.

METHODS

Gene expression was quantified by Real Time PCR in polyps (n=35) and in healthy nasal mucosa (n=15).

RESULTS

Eosinophilic polyps showed a higher expression of eotaxin-2 and RANTES, but not of CCR-3, ICAM-1 or LFA-1 compared to control nasal mucosa.

CONCLUSION

Eosinophilic polyps present greater expression of eotaxin-2 and RANTES, but not of CCR-3, ICAM-1 or LFA-1 compared to control nasal mucosa.

Serum interleukin-16 levels in patients with nasal polyposis

OBJECTIVE/HYPOTHESIS

Several inflammatory and allergic disorders have been reported to correlate with interleukin-16 (IL-16). IL-16 is a highly potent chemotactic and chemoattractant molecule for eosinophils. Nasal polyposis (NP) has an inflammatory basis, and eosinophilia is a common finding in polyp tissue. In this study, we aimed to determine serum IL-16 levels in NP patients.

STUDY DESIGN

Prospective controlled study in a tertiary academic hospital.

METHODS

Peripheral blood samples were obtained and used for serologic studies with enzyme-linked immunosorbent assay kits to determine IL-16 levels.

RESULTS

The study and the control groups consisted of 17 and 10 patients, respectively. Mean serum IL-16 levels were significantly higher in the study group when compared to the control group (447.9 pg/mL vs. 260.2 pg/mL) (P < .001).

CONCLUSIONS

Serum IL-16 levels are significantly elevated in NP patients. This finding may represent identification of a valuable serum biomarker and potential therapeutic target in NP patients.

Plasma RANTES and eotaxin levels are correlated with the severity of chronic rhinosinusitis

Eosinophilia occurs in up to 75-90% of nasal polyps in Caucasians. The chemokines eotaxin and RANTES increase eosinophil recruitment, activation, and survival, and these chemokines are significantly expressed in nasal polyps. We hypothesized that eotaxin and RANTES plasma levels might be correlated with disease severity. We compared the eotaxin and RANTES plasma levels in 20 Taiwanese patients with chronic rhinosinusitis and nasal polyps and 20 Taiwanese healthy controls. Eotaxin and RANTES plasma levels were measured by ELISA and disease severity was scored by CT scans. Compared to controls, patients with nasal polyps had significantly elevated plasma levels of eotaxin and RANTES and increased peripheral blood eosinophils (p < 0.001). Eotaxin plasma levels were significantly correlated with disease severity in patients with chronic rhinosinusitis to a greater extent than were RANTES levels. RANTES and eotaxin levels were also positively correlated with the percentages of peripheral blood eosinophils. Eotaxin plasma levels are significantly correlated with disease severity in Taiwanese patients with nasal polyposis to a greater degree than are RANTES levels. Additional studies are needed to assess whether eotaxin plasma levels can be used to monitor disease progression and attenuation.

Pro-inflammatory effects of ochratoxin A on nasal epithelial cells

Eosinophilic chronic rhinosinusitis (ECRS) largely consists of allergic fungal sinusitis, non-allergic fungal rhinosinusitis, aspirin-exacerbated ECRS, and superantigen-induced ECRS. The pathophysiology of ECRS is not completely understood, in particular, the role of mycotoxins remains unknown. The aim of this study was to evaluate the effects of one of the most widespread mycotoxin, ochratoxin A (OTA), on the release of pro-inflammatory cytokines such as interleukin-(IL)-6 and the CXC-chemokine IL-8 from nasal epithelial cell cultures (NEC) of subjects with and without ECRS. NEC (ECRS group: n = 16; controls: n = 7) were stimulated with OTA for 24 h. Protein concentrations of IL-6 and IL-8 levels were measured in NEC supernatants by ELISA prior and 24 h after addition of OTA. Baseline levels in the supernatants of NEC were 183.3 pg/ml for IL-6 and 384.6 pg/ml for IL-8. Stimulation with OTA induced a significant increase of IL-6 (p < 0.001) and IL-8 (p < 0.001) in both NEC of controls and ECRS, respectively. There were no significant differences between controls and ECRS. This is the first study evaluating the effects of a mycotoxin on epithelial airway cells. Our data show that the ubiquitous mycotoxin OTA has a strong pro-inflammatory effect on NEC resulting in the release of IL-6 and IL-8. Mycotoxins may promote inflammation in nasal mucosa.

Contribution of the proinflammatory cytokine IL-18 in the formation of human nasal polyps

Nasal polyposis is a chronic inflammatory disease of the nasal mucosa. The etiology and the mechanisms of formation of nasal polyps are still not clear. Interleukin (IL)-18 is a novel proinflammatory cytokine that plays important roles in regulating immune inflammatory responses. However, the presence of IL-18 in human nasal mucosa and its roles in the inflammatory process of nasal polyps has not been studied yet. In this study, it was the first time to investigate the expression of IL-18 in human nasal mucosa and nasal polyps, and its potential function in the formation of nasal polyps. Surgical samples were analyzed by Western blot and immunohistochemistry to evaluate the expression and location of IL-18, and its correlated cytokines, IL-4, and IFN-γ. Furthermore, the airway epithelial cell line, A549, was used to investigate the mutual regulation of IFN-γ, IL-4, and IL-18. IFN-γ, IL-4, and IL-18 were all highly expressed in the epithelial cells, submucosal glands, and infiltrating inflammatory cells in the nasal polyp tissues, comparing with the control samples. Especially, the expression of IL-18 was upregulated significantly in nasal polyp tissues compared with control tissues. In addition, IL-18 was expressed in A549 cells in response to lipopolysaccharide and IL-4. Our data suggest that nasal epithelial cells are involved in the pathogenesis of nasal polyps formation and potentially via the secretion of IL-18, which is likely to play important roles in the formation of nasal polyps.

Staphylococcus aureus invades the epithelium in nasal polyposis and induces IL-6 in nasal epithelial cells in vitro

BACKGROUND

Staphylococcus aureus has been associated with chronic rhinosinusitis with nasal polyps (CRSwNP) pathogenesis but its role is still controversially discussed. Here, we demonstrate S. aureus detection in the mucosa of CRSwNP. In addition, intracellular residency of S. aureus in nasal polyp epithelial cells (NPECs) and its capability to induce TH-2 cytokines were analyzed in vitro.

METHODS

Staphylococcus aureus detection in CRSwNP (n = 25), CRS without polyps (CRSsNP, n = 5), and turbinate mucosa (TM, n = 10) was performed by peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) and microbial cultivation from tissue biopsies. Intracellular residency was examined by intracellular persistence assay and electron microscopy. IL-6 and IL-13 responses to S. aureus infection and supernatants were quantified by ELISA.

RESULTS

Peptide nucleic acid-fluorescence in situ hybridization positive bacterial cells were significantly increased in the epithelium of CRSwNP (17/25) compared to CRSsNP (0/5) and TM (1/10). Good concordance of PNA-FISH results and S. aureus cultivation was found applying Cohen's κ for CRSwNP (κ = 0.841) and TM (κ = 1.0). Intracellular persistence assay with S. aureus strain Newman and its corresponding small-colony variant mutant strain III33 demonstrated intracellular survival and replication of S. aureus within NPECs. Both S. aureus strains significantly induced IL-6 but not IL-13 in infected NPECs and in NPECs challenged with corresponding staphylococcal supernatants.

CONCLUSION

Invasion of the epithelium by S. aureus was a phenomenon seen predominantly in CRSwNP. Regardless of an intra- or extracellular localization in the epithelium, S. aureus is capable to induce IL-6 synthesis in vitro and thus may contribute to the TH-2 cytokine pattern in CRSwNP.

Evidence for altered activity of the IL-6 pathway in chronic rhinosinusitis with nasal polyps

BACKGROUND

IL-6 activates T(H)17 cells and regulates the response of B lymphocytes and regulatory T cells. The IL-6 receptor and the membrane protein, glycoprotein 130 (gp130), form an active signaling complex that signals through signal transducer and activator of transcription 3 (STAT3) and other signaling molecules. Both the IL-6 receptor (IL-6R) and gp130 can be found in soluble forms that regulate the pathway.

OBJECTIVE

We measured IL-6 signaling components and IL-17 in chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP), CRS without nasal polyps (CRSsNP), and controls to assess the IL-6 pathway in CRS.

METHODS

IL-6, soluble IL-6R, soluble gp130 (sgp130), and IL-17 were measured in sinus tissue extracts and in nasal lavage fluid by either cytokine bead array or ELISA. phosphoSTAT3 (p-STAT3) was determined by Western blot and by immunohistochemistry.

RESULTS

IL-6 protein was significantly (P < .001) increased in CRSwNP compared with CRSsNP and controls. Soluble IL-6R was also increased in nasal polyp compared with control tissue (P < .01). Despite elevated IL-6 and sIL-6R, IL-17A, E, and F were undetectable in the sinus tissue from most of the patients with CRS and controls. p-STAT3 levels were reduced in the polyp tissue, possibly indicating reduced activity of IL-6 in the tissue. sgp130 was elevated in CRSwNP compared with CRSsNP and controls.

CONCLUSION

p-STAT3 levels are decreased in CRSwNP despite increased levels of IL-6 and sIL-6R and are associated with the absence of an IL-17 response. This may be a response to elevated levels of sgp130, a known inhibitor of IL-6 signaling. These results indicate that IL-6 and its signaling pathway may be altered in CRSwNP.

Vitamin D derivatives: calcitriol and tacalcitol inhibits interleukin-6 and interleukin-8 expression in human nasal polyp fibroblast cultures

PURPOSE

Biologically active vitamin D3 (VD) derivatives possess modulatory activities on immunological and inflammatory responses which can be reflected by altered levels of pro-inflammatory chemokines. Nasal polyposis (NP), defined as a chronic inflammatory process of upper respiratory system, could be influenced by VD derivatives. The purpose of this study was to investigate the influence of 1alpha,25-dihydroxyvitamin D3 (calcitriol) and 1alpha,24(R)-dihydroxyvitamin D3 (tacalcitol) on the secretion of IL-6 and IL-8 by fibroblasts derived from NP.

MATERIAL AND METHODS

The study involved 12 fibroblast cultures derived from NP samples obtained from surgically treated patients. Measurements were performed on the polyp cells after the 6-9 passages. Culture stimulation involved treatment with tacalcitol and calcitriol at a defined strength (from 10(-7)M to 10(-4)M). IL-6 and IL-8 concentrations were estimated with ELISA.

RESULTS

Treatment with calcitriol or tacalcitol inhibits the synthesis of both IL-6 and IL-8 compared to the control group. The dose dependence of this effect has been confirmed. VD derivatives influence was marked at higher concentrations. Significant interleukin decrease was observed at 10(-5) and 10(-4) for calcitriol and 10-4 in the case of tacalcitol.

CONCLUSIONS

The present study demonstrates that calcitriol and tacalcitol are capable of affecting pro-inflammatory cytokine (IL-6 and IL-8) levels in NP cultures. Our data imply a potential therapeutical application of topical VD derivates in NP and warrant further investigation.

Gene-expression signatures of nasal polyps associated with chronic rhinosinusitis and aspirin-sensitive asthma

PURPOSE OF REVIEW

The purpose of this review is to highlight recent advances in gene-expression profiling of nasal polyps in patients with chronic rhinosinusitis and aspirin-sensitive asthma.

RECENT FINDINGS

Gene-expression profiling has allowed simultaneous interrogation of thousands of genes, including the entire genome, to better understand distinct biological and clinical phenotypes associated with nasal polyps. The genes with altered expression in nasal polyps are involved in many cellular processes, including growth and development, immune functions, and signal transduction. The wide-ranging and typically nonoverlapping results reported in the published studies reflect methodological and demographic differences. The identified genes present possible novel therapeutic targets for nasal polyps associated with chronic rhinosinusitis and aspirin-sensitive asthma.

SUMMARY

Gene-expression profiling is a powerful technology that allows definition of expression signatures to characterize patient subgroups, predict response to treatment, and offer novel therapies. Although the ability to interpret the meaning of the individual gene in these signatures remains a challenge, integrated analysis of a large number of these signatures with other genome-scale data sets and more traditional targeted approaches has a potential to revolutionarize understanding and treatment of chronic rhinosinusitis and aspirin-sensitive asthma.

Interleukin-6 is essential for Staphylococcal exotoxin B-induced T regulatory cell insufficiency in nasal polyps

BACKGROUND

The pathogenesis of nasal polyps is still unclear. There is increasing evidence indicating that Staphylococcal aureus (S. aureus) is associated with the formation of nasal polyps, but the mechanism has not been well documented to date.

METHODS

We stimulated cultured nasal polyps and turbinate tissues with Staphylococcal exotoxin B (SEB), detected the expression of pro-inflammatory cytokines (IL-2, IL-6, and IL-8) and T cell cytokines (IFN-gamma, IL-4, IL-5, IL-10, and IL-17) in the supernatants, and evaluated mRNA expression (T-bet, GATA-3, Foxp3, and RORgammat) and frequencies of CD4+CD25+ T regulatory cells (Tregs) in nasal tissues. We also evaluated the effects of blocking IL-6 with monoclonal antibodies to T cell profiles in cultured nasal tissues stimulated by SEB.

RESULTS

Levels of IL-6, IFN-gamma and IL-4 increased significantly in SEB-stimulated nasal polyps. Meanwhile, mRNA expressions of T-bet and GATA-3 were significantly up-regulated, while Foxp3 was inhibited and the frequencies of CD4+CD25+ Tregs were decreased after SEB stimulation. After blocking IL-6, the levels of IL-10 and Foxp3 mRNA, as well as the frequencies of CD4+CD25+ Tregs, were significantly increased, while IFN-gamma and IL-4 production and the mRNA expression of T-bet and GATA-3 were significantly inhibited.

CONCLUSIONS

SEB is able to modulate pro-inflammatory factors, T-helper type 1/Th2 profiles and suppress Treg activity in cultured nasal polyps, which were rescued by blocking IL-6 activity. Therefore, IL-6 is essential for SEB-induced Treg insufficiency in nasal polyps.

Perspectives on the etiology of chronic rhinosinusitis: an immune barrier hypothesis

BACKGROUND

Chronic rhinosinusitis (CRS) has been defined as persistent symptomatic inflammation of the nasal and sinus mucosa resulting from the interaction of multiple host and environmental factors. Recent studies have implicated Alternaria fungi or toxigenic Staphylococcus aureus as critical agents in CRS pathogenesis. The emphasis on environmental agents in CRS etiology has focused interest toward elimination of those agents as the prime mechanism of therapy. This viewpoint is in marked contrast to the current perspective on some other chronic inflammatory epithelial disorders that afflict the skin, lungs, and gut, wherein host factors are believed to predispose to disease expression in the presence of ubiquitous environmental agents.

METHODS

The current review evaluates CRS etiology from this perspective and considers that CRS develops, in part, as an outcome of a dysfunctional host response. Specifically, evidence from our laboratory and others will be reviewed indicating that CRS is associated with a failure of the mechanical and immunologic barriers across the nasal mucosa. The hypothesis would further propose that genetic and epigenetic variation predisposes susceptible individuals to barrier failure in the presence of environmental stress leading to CRS.

RESULTS

From this unifying perspective, bacteria and fungi are seen as disease modifiers rather than primary etiologic agents.

CONCLUSION

The goal is to place concepts of CRS pathophysiology in a framework consistent with a current understanding of chronic inflammation in general and epithelial disease in particular.

Inflammatory genes in nasal polyposis

PURPOSE OF REVIEW

This paper is a review of the most recent literature concerning the role of inflammatory genes in nasal polyposis. The data provide evidence of a pivotal role for some inflammatory mediators in the development and maintenance of nasal polyps.

RECENT FINDINGS

Nasal polyposis is a common disease of the nasal mucosa; the exact mechanisms leading its development are still unknown. The role of the immune system in the pathogenesis of this disease is poorly understood. This lack of understanding makes definitive treatment very difficult. Activated eosinophils are a prominent feature of nasal polyps. Their presence in tissue results from a complex series of events that regulates their influx from the vasculature, as well as their movement, activation and survival within the tissue. Several studies have demonstrated that there are many potent chemoattractants that can activate eosinophils and trigger the inflammatory response.

SUMMARY

Cytokines, chemokines and growth factors play an important role in the persistence of mucosal inflammation associated with nasal polyps. Metalloproteinases seem to be crucial in nasal tissue remodeling in these patients. Arachidonic acid metabolites seem to be particularly important in the pathogenesis of nasal polyps in patients with aspirin hypersensitivity. We discuss the contribution of each one for the polyp formation.

Microarray cDNA to identify inflammatory genes in nasal polyposis

BACKGROUND

The objective of this study was to investigate the spectrum of inflammatory gene expression in patients with nasal polyposis.

METHODS

The cDNA microarray technique was used to identify gene expression in tissue samples from nasal polyps and adjacent inflammatory nasal mucosa of 21 patients with nonallergic nasal polyposis. To validate the microarray analysis, we compared the expression of five genes by reverse transcription-polymerase chain reaction (RT-PCR): tumor necrosis factor, IL-5, IL-9, fibroblast growth factor, and transforming growth factor (TGF)-beta1.

RESULTS

We tested 96 different inflammatory genes in our samples. Thirty-six genes exhibited differences in expression between the two tissue types. In all 36 genes the level of expression was greater in the inflammatory mucosa than the polyps. The RT-PCR confirmed the cDNA results.

CONCLUSION

We believe that the high expression of TGF-beta1 in inflammatory mucosa compared with the low expression in polyps may reflect an important role in the inhibitory mechanisms of nasal polyposis.

Tissue remodelling in upper airways: where is the link with lower airway remodelling?

Tissue remodelling reported in upper airways include epithelial hyperplasia, increased matrix deposition in the nasal or paranasal lining, matrix degradation and accumulation of plasma proteins. Genetic influences, foetal exposures and early life events may contribute to structural changes such as subepithelial fibrosis from an early age. Other structural alterations are related to duration of the disease and long-term uncontrolled inflammation. Structural changes may increase alteration of the protective functions of the upper airways namely by affecting mucociliary clearance and conditioning of inspired air. The sequences of tissue changes during wound repair of upper airway mucosa after surgery are illustrative of the complexicity of tissue modelling and remodelling and could be considered as an important source of information for a better understanding of the complex relationship between inflammatory reaction, of the subsequent tissue damages and fibroblast metabolism of upper airways.

Endoscopic endonasal sinus surgery: a review of 18 years of practice and long-term follow-up

A study of 1,915 patients operated on with a total of 4,285 endoscopic endonasal ethmoidal procedures during a period of 18 years is presented. The study comprises five groups of patients with (1) acute recurrent and chronic sinusitis--long-standing symptoms >3 months--(n = 733), (2) nasal/paranasal polyposis (n = 710), (3) sinogenic headache (n = 325), (4) mucoceles (n = 59) and (5) other nasal/paranasal disorders (n = 88). This group includes acute sinus infection with complications (n = 38), acute trauma/injury (n = 22), Grave's disease with exophthalmus (n = 12) and olfactory dysfunction (n = 16). The need for a thorough examination leading to a final diagnosis is emphasized. Endoscopy and CT/MRI are standard tools in the diagnostic and postoperative process. Close cooperation and educational teaching of the patient are necessary to obtain highest compliance. Long-standing medical treatment of inflammatory diseases is important to the long-term outcome and is of utmost importance to surgical success. Surgery is recommended to be performed under general anesthesia (total intravenous anesthesia or laryngeal mask anesthesia) with additional local, topical anesthetics, and can be easily performed on a day-case out-patient basis. The surgery is based upon the Messerklinger technique (MT). Peroperative complications are reduced by a skilled and meticulous surgical conduct and an adequate medication preoperatively. During this period of time, necessary controls within the first postoperative month were reduced from 3-4 to only one. Long-term follow-up secures a long-standing optimal result. Endoscopic surgery for more rare conditions, such as orbital decompression, CSF leaks and meningoceles, is recommended to be performed in specialized centers with adequate trained staff and necessary equipment. The possibilities of the picture archiving communication system, giving a number of different projections and angles and video-guided imaging peroperatively, facilitates safe surgical performances in areas usually associated with great risks and hazards. The long-term results are very good during the above circumstances. Reoperations are few and the patient satisfaction is very high.