Interleukin-8 gene expression in chronic sinusitis

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

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

Expression of Interleukin-5, Interleukin-8, and Interleukin-10 mRNA in the Osteomeatal Complex in Nasal Polyposis

Background

Several cytokines are expressed in chronic sinusitis with and without underlying allergy. Their local production and regulation in the osteomeatal complex, the key area of paranasal sinuses, still is not fully understood. This study was performed to investigate differences of cytokine messenger RNA (mRNA) expression between the medial and the lateral part of the middle turbinate and anterior ethmoid mucosa of allergic and nonallergic patients.

Methods

Using the LightCycler system for real-time reverse-transcription polymerase chain reaction, we investigated the content of interleukin (IL)-5, IL-8, and IL-10 mRNA in tissue samples from middle turbinates and anterior ethmoids of 18 patients with chronic sinusitis and nasal polyps. Inferior turbinate mucosa of six control subjects without sinusitis and allergy served as control.

Results

IL-5 mRNA was detectable in 32 (60%) of 54 samples (two of six controls) in significant different amounts between the various locations (p ≤ 0.001). Anterior ethmoid mucosa (0.96 ± 0.99) expressed the highest amount of IL-5 mRNA followed by the lateral (0.37 ± 0.54) and the medial portion of the middle turbinate (0.12 ± 0.29) with no difference between allergic and nonallergic subgroups. IL-8 was detected in significant higher amounts in all three origins with no significant difference in concentrations between the examined locations as compared with controls. Patients expressed either IL-5 or IL-8 or both cytokine mRNA. IL-10 was expressed in all three specimens from five of eight allergic patients. All five individuals with clinical symptoms of allergy at the time of operation expressed IL-10 in at least one specimen.

Conclusions

IL-5 cytokine expression in the osteomeatal complex is linked to the presence of nasal polyps, whereas IL-8 is up-regulated without distinct correlation to nasal polyps. IL-10 expression was detectable in five of eight allergic patients.

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.

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.

Effects of long-term clarithromycin treatment on lavage-fluid markers of inflammation in chronic rhinosinusitis

Macrolides can be clinically effective in chronic rhinosinusitis (CRS). However, little is known about how these drugs affect pathophysiological features of CRS in vivo. In the present study, patients with CRS were subjected to long-term treatment with clarithromycin. Nasal lavages with and without histamine (40 and 400 microg ml(-1)) were carried out prior to and late into the treatment period. Histamine was included as a tool to produce plasma exudation, a process known to move free cellular products from the mucosal tissue into the airway lumen thereby enriching nasal surface liquids with such products. Interleukin-8 (IL-8), myeloperoxidase (MPO), eosinophil cationic protein (ECP), alpha(2)-macroglobulin and fucose were monitored as indices of pro-inflammatory cytokine production, neutrophil and eosinophil granulocyte activities, plasma exudation and mucinous secretion, respectively. Clarithromycin reduced the lavage fluid levels of IL-8 at the low-dose histamine observation (P<0.001). There was a trend towards reduced MPO by the treatment, whereas ECP was significantly reduced at the low-dose histamine observation (P<0.05). alpha(2)-Macroglobulin was reduced by clarithromycin (saline lavages) (P = 0.05), whereas fucose was unaffected. The exudative responsiveness to high-dose histamine was significantly reduced by the treatment (P<0.05). Furthermore, significantly lower levels of fucose were observed at the low-dose histamine observation (P<0.01). We conclude that long-term clarithromycin treatment likely exerts an anti-inflammatory effect in CRS.

Inflammatory pathway gene expression in chronic rhinosinusitis

BACKGROUND

The main objective in this preliminary experiment was to compare gene expression in the sinus mucosa of patients with chronic hyperplastic rhinosinusitis (CRS) against normal subjects, using gene microarray technology. The specific aim was to examine alterations in inflammatory mediator expression in patients with CRS. We performed a prospective experimental study.

METHODS

Total RNA samples were obtained from the sinus mucosa biopsies of 14 patients with chronic hyperplastic sinusitis and 4 normal controls, using the Affymetrix recommended protocol. The data for 22,000 genes on the GeneChip U133A were generated from 18 hybridizations. Affymetrix GeneChip 5.0 was used as the image acquisition software for the U133A chips. Data normalization, log transformation, statistical analysis, and pattern study were performed with GeneSpring software. Comparison between patients with CRS and normal controls were performed using the Welch t-test, with log transformed data.

RESULTS

There were a total of 1283 genes scored as differentially expressed between groups. The value of p, the probability of a false positive, was set to <0.05. Hierarchical clustering was applied to study coexpression patterns of the 1283 significant genes. The inflammatory pathway was overlaid with the differential expressed gene list. Four genes involved in the inflammatory pathway, interleukin (IL)-6, IL-12A, IL-13, and tumor necrosis factor (TNF) alpha (2) were consistently overexpressed in patients with hyperplastic CRS.

CONCLUSION

There is overexpression of four major genes of the inflammatory pathway (IL-6, IL-12A, IL-13, and TNF-alpha (2)) in patients with CRS compared with the normal population. Defining gene expression profiles may help elucidate new key factors in the pathogenesis of CRS and perhaps aid in the development of new therapeutic modalities.

Expression of Syk is associated with nasal polyp in patients with allergic rhinitis

OBJECTIVE

Numerous signalings are involved in allergic inflammation. The non-receptor protein tyrosine kinase, Syk, is widely expressed in immune-potentiated cells and plays critical roles in initiating signal transduction in response to the activation of cytokine, chemokine and other types of receptors. It has been hypothesized that Syk expression in allergic nasal mucosa and polyps with allergy is different from non-allergic mucosa, and that changes in Syk expression contribute to the activation of allergic reactions.

METHODS

We examined whether the expression of Syk is found in allergic nasal mucosa and polyps. We investigated the expression of Syk in 46 nasal mucosa and polyps (14 samples from patients with allergic rhinitis and 32 samples with non-allergic chronic sinusitis) using an immunohistochemical technique.

RESULTS

Allergic polyps had more Syk positive cells than non-allergic polyps. Syk positive cells were determined to mainly be eosinophils. There was no difference in Syk expression in the lamina propria and nasal gland between allergic mucosa and non-allergic mucosa.

CONCLUSION

Eosinophils in allergic polyps receive an intracellular signal, although the signal is not able to determine the function in the present state. Syk appears to be a promising target molecule for anti-allergic inflammation in allergic rhinitis.

The role of sinus disease in asthma

PURPOSE OF REVIEW

Some time ago, a link between upper and lower respiratory disease was described, which gave rise to the concept of 'united airways disease'. This concept primarily refers to the well established link between allergic rhinitis and asthma, but it also covers a possible link between sinus disease and asthma (allergic or nonallergic) and other lower airway disease.

RECENT FINDINGS

The current classification of chronic rhinosinusitis (CRS) includes disease without and with nasal polyps, which are considered subgroups of CRS. Different patterns of inflammatory and regulatory cytokines (involving distinguishable T-helper lymphocyte populations) and of remodelling markers, however, were recently described to differentiate nasal polyposis from CRS, yielding two discrete entities. These patterns resemble those of lower airway diseases, such as asthma and chronic obstructive pulmonary disease, and suggest a common aetiological/pathogenetic background. Whereas the link between nasal polyps and asthma is well established (indeed, asthma improves after medical or surgical treatment of sinus disease), that between CRS and lower airway disease is not well understood. Recently, Staphylococcus aureus enterotoxins, acting as superantigens, were identified as a possible link between nasal polyps and asthma, resulting in severe disease manifestations in both upper and lower airways.

SUMMARY

The role played by sinus disease in asthma is only partially understood, largely because of deficits in the clinical classification and in basic knowledge of pathophysiological pathways. Recent research into upper airway and sinus inflammation and remodelling may reveal new perspectives and lead to a classification of sinus disease, which will facilitate appropriate clinical and epidemiological studies.

In vivo relationship between collagenase-2 and interleukin-8 but not tumour necrosis factor-alpha in chronic rhinosinusitis with nasal polyposis

BACKGROUND

The characteristic feature of chronic rhinosinusitis with nasal polyposis (CRSwNP) is eosinophilic inflammation of the sinus mucosa; a type of inflammation also seen in asthmatic airways. Similar histopathologic findings of airway remodelling are present in both diseases. Remodelling is tightly controlled by matrix metalloproteinases (MMP). Increase of collagenase-2 (MMP-8) expression in the bronchial epithelial cells has been described in asthmatic patients, but it has not been studied in CRSwNP.

METHODS

The concentrations and degree of activation of MMP-8 were analysed by immunofluorometric assay and Western blotting, respectively, in sinus mucus samples from CRSwNP patients and in nasal lavages from healthy controls in relation to inductive cytokines interleukin-8 (IL-8) and tumour necrosis factor-alpha (TNF-alpha).

RESULTS

Significantly elevated levels of MMP-8 and IL-8 but not TNF-alpha were found in CRSwNP patients relative to controls. In particular, the activation of mesenchymal-type MMP-8 but not polymorphonuclear-type MMP-8 was associated with elevated IL-8 levels.

CONCLUSIONS

The IL-8 and MMP-8 seemingly form an inductive cytokine-proteinase cascade in CRSwNP pathogenesis. Together they provide a target for novel therapies and a diagnostic tool for monitoring CRSwNP treatment.

Clinical implications of the immunomodulatory effects of macrolides on sinusitis

This article reviews the treatment of chronic sinusitis with macrolides. Chronic sinusitis is often the result of bacterial infections that lead to chronic inflammation with thickening of the sinus mucosa and hypersecretion of mucus. In addition to their anti-infective properties, some macrolides possess immunomodulatory effects. These macrolides have been used successfully to treat diffuse panbronchiolitis, a progressive inflammatory lung disease, and may be useful for treatment of asthma, chronic bronchitis, chronic sinusitis, cystic fibrosis, and bronchiectasis. The clinical benefits of macrolides in patients with chronic sinusitis include decreased nasal secretions and postnasal drip, with improvement in nasal obstruction. In vivo and in vitro studies show that some macrolides affect neutrophil chemotaxis and infiltration, inflammatory cytokine production, mucus production, and the transportability of airway secretions. These findings indicate that macrolides are promising agents for treating chronic inflammation of the airways.

Cytokine profile in paranasal effusions in patients with chronic sinusitis using the YAMIK sinus catheter with and without betamethasone

Recently, the YAMIK sinus catheter (YAMIK) has been reported to be a useful therapeutic device in the treatment of sinusitis. The present study was conducted to compare its delivery of either a normal saline (NS) or a betamethasone solution (0.4 mg/ml) into the paranasal sinuses of 25 patients (39 sides) with chronic sinusitis. The following parameters were evaluated: (1) subjective nasal clinical symptoms (nasal discharge, nasal obstruction, postnasal drip and headache), (2) X-ray photographs (ethmoid and maxillary sinuses) and (3) cytokine levels (IL-1beta, IL-8 and TNF-alpha) by enzyme-linked immunosorbent assay. The total nasal symptom scores significantly decreased after the first therapy, and the total X-ray photograph scores significantly decreased after therapy with either NS or the betamethasone solution. In both NS and betamethasone patients, the levels of IL-1beta and IL-8 had significantly decreased by the 3rd and 2nd weeks after therapy, respectively. In contrast, the TNF-alpha level decreased after the first therapy with betamethasone solution and remained unchanged after therapy with NS. These findings suggest that evacuation of the pathological effusions in sinuses may exert a beneficial effect by reducing the levels of IL-1beta and IL-8, and we speculate that removal of pathological effusions from the sinuses may provide treatment through different mechanisms than those that occur in treatment with betamethasone.

Fosfomycin nebulizer therapy to chronic sinusitis

OBJECTIVE

effects of Fosfomycin (FOM) nebulizer therapy were studied in patients with chronic sinusitis.

METHODS

about 28 patients with chronic sinusitis were administered 2 ml of FOM sodium (3% w/v) by nebulizer three times per week for 4 weeks. Levels of IL-1 beta, IL-6, IL-8, and TNF-alpha in nasal lavage were also measured before and at the end of treatment.

RESULTS

the overall efficacy of this treatment on the basis of both subjective and objective symptoms, was 'excellent' for 28.6%, 'good' for 10.7%, 'fair' for 39.4%, and yield 'no change' for 21.4% of the patients. Both IL-1 beta and IL-6 concentrations were significantly decreased after treatment. Although the IL-8 level did not significantly decrease, it seems to be related to the overall efficacy. TNF-alpha was not detected in all of the samples.

CONCLUSION

FOM nebulization therapy is highly effective in treatment for chronic sinusitis, and efficacy may be due to an immunomodulatory mechanism, as well as its bactericidal effect.

Application of YAMIK sinus catheter for patients with paranasal sinusitis with and without nasal allergy

PURPOSE

YAMIK sinus catheter (YAMIK) has already been reported to be a useful therapeutic device for sinusitis cases. The purpose of this study was to compare the effectiveness of YAMIK in sinusitis cases with and without nasal allergy in order to contribute toward establishing its indication.

METHODS

YAMIK was tried in 10 chronic sinusitis cases complicated with nasal allergy and 20 cases without nasal allergy. Clinical symptoms, endoscopic findings and pathological opacification in X-ray photographs were compared in these cases with and without nasal allergy.

RESULTS

No significant differences were seen in the effectiveness of YAMIK between cases with and without nasal allergy.

CONCLUSION

These findings suggest that YANIK is useful and applicable even in sinusitis cases complicated with nasal allergy.

Chronic sinusitis

Sinusitis is a very common chronic illness with a substantial health care impact. This review focuses on factors contributing to sinusitis pathogenesis and chronicity, including anatomic factors, disturbances in mucociliary clearance, microbial pathogens, and inflammatory factors. A distinction is made between "infectious" and "noninfectious" types of inflammation in chronic sinusitis. The inflammatory characteristics of noninfectious inflammation are reviewed primarily in the context of chronic hyperplastic sinusitis with nasal polyposis. Key features of this type of inflammation include the presence of chronic inflammatory cells, large numbers of eosinophils, and IL-5-producing T lymphocytes. Allergic fungal sinusitis is discussed as a special type of chronic sinusitis. Published studies on the outcomes of medical management are reviewed. Finally, algorithms for medical management of chronic sinusitis and allergic fungal sinusitis are presented.

Nasal interleukin-5, immunoglobulin E, eosinophilic cationic protein, and soluble intercellular adhesion molecule-1 in chronic sinusitis, allergic rhinitis, and nasal polyposis

OBJECTIVE

To compare concentrations of interleukin-5 (IL-5), immunoglobulin E (IgE), eosinophilic cationic protein (ECP), and soluble intercellular adhesion molecule-1 (sICAM-1) in nasal secretion and serum of patients with chronic nonallergic sinusitis, allergic rhinitis, and nonallergic nasal polyposis to obtain information about the pathogenesis of these diseases.

METHODS

Nasal secretion and serum were analyzed by routine enzyme-linked immunosorbent assay techniques. Nineteen patients with chronic nonallergic sinusitis, 24 patients with seasonal allergic rhinitis, and 18 patients with nonallergic nasal polyposis were included in the study. Eight healthy, nonallergic probands served as control subjects.

RESULTS

Significantly elevated concentrations of IL-5 (5-fold, P < .05) and IgE (15-fold, P < .01) were detected in nasal secretion of patients with allergic rhinitis (IL-5, 51.8 +/- 13.2 pg/mL; IgE, 41.9 +/- 20.9 kU/L) or nonallergic nasal polyposis (IL-5, 57.9 +/- 36.9 pg(mL; IgE, 40.5 +/- 20.2 kU/L) compared with controls (IL-5, 10.6 +/- 7.8 pg/mL; IgE, 2.8 +/- 0.5 kU/L) or with patients with chronic nonallergic sinusitis (IL-5, 16.5 +/- 13.2 pg/mL; IgE, 5.4 +/- 3.1 kU/L). There were no significant differences between patients with allergic rhinitis and those with nonallergic nasal polyposis. Concentrations of ECP were significantly elevated (sixfold, P < .01) in patients with allergic rhinitis (297.8 ng/mL +/- 173.1) compared with controls (52.4 +/- 28.0 ng/mL) or patients with chronic nonallergic sinusitis (44.8 +/- 40.1 ng/mL), whereas twofold higher concentrations (not significant) of ECP were observed in patients with nonallergic nasal polyposis (107.1 +/- 26.6 ng/mL). Significantly elevated concentrations of sICAM-1 in nasal secretion (threefold, P < .05) were detected only in patients with chronic nonallergic sinusitis (79.4 +/- 45.6 ng/mL). The elevated sICAM-1 nasal secretion values in this group correlated significantly (P < .05) to the serum values.

CONCLUSIONS

Equally elevated concentrations of IL-5 and IgE in patients with allergic rhinitis and nonallergic nasal polyposis implicated similar pathogenic processes in both diseases. Whereas the pathogenesis of allergic rhinitis is IgE-specific, the pathogenesis of nasal polyps is not as clear. IL-5 was suggested to play a pivotal role in tissue eosinophilia, which was confirmed by data in the present study. Elevated concentrations of ECP were suggested to result from tissue eosinophilia--a characteristic of both diseases. Elevated concentrations of sICAM-1 in patients with chronic nonallergic sinusitis pointed to its key role in the recruitment of neutrophils into the inflamed tissue, whereas an important role in eosinophil recruitment was ruled out.

Macrolide treatment decreased the size of nasal polyps and IL-8 levels in nasal lavage

Recently, epidemiologic and experimental studies have been reported that long-term macrolides are effective for the treatment of chronic airway inflammatory diseases including diffuse panbronchiolitis, chronic rhinosinusitis, and cystic fibrosis (Jaffe A, Francis J, Rosenthal M, et al. Long-term azithromycin may improve lung function in children with cystic fibrosis. Lancet 351:420, 1998), and that macrolides can directly reduce the production of IL-8 by nasal epithelial cells (Suzuki H, Shimomura A, Ikeda K, et al. Inhibitory effect of macrolides on interleukin-8 secretion from cultured human nasal epithelial cells. Laryngoscope 107:1661-1666, 1997). In this study we administered macrolides with 14-membered rings to patients with nasal polyps due to chronic rhinosinusitis for at least 3 months and measured the IL-8 level in nasal lavage from those patients. The IL-8 levels in nasal lavage from patients with nasal polyps were reduced during macrolide treatment. There was significant correlation between decreased IL-8 levels in nasal lavage and the clinical effect of macrolides on the size of the nasal polyps. In the group whose polyps were reduced in size, the IL-8 levels dramatically decreased from 231.2 pg/mL to 44.0 pg/mL (p < 0.05), and were significantly higher before macrolide treatment than those in the group whose polyps showed no change (p < 0.005). This reduction in IL-8 may be an important aspect of the effect of macrolide treatment on nasal polyps in chronic rhinosinusitis.

Increased expression of IL-4, IL-5, IFN-gamma, IL-6, IL-8, and TGF-beta mRNAs in maxillary mucosa of patients with chronic sinusitis

This study aimed to investigate expression of various cytokine mRNAs, including IL-6, IL-8, TGF-beta, IL-4, IL-5, and IFN-gamma in maxillary sinus mucosa of patients with chronic sinusitis. Maxillary sinus mucosae of six patients with chronic sinusitis and turbinate mucosae of six healthy subjects were obtained. We performed RT-PCR and Southern blot to examine gene expression of the cytokines IL-6, IL-8, TGF-beta, IL-4, IL-5, and IFN-gamma in maxillary sinus mucosa and compared the results with cytokine gene expressions in normal turbinate mucosa. IL-6, IL-8, TGF-beta, IL-4, IL-5, and IFN-gamma mRNAs were expressed more frequently in maxillary sinus mucosa from patients with chronic sinusitis than in normal turbinate mucosa. All the maxillary sinus mucosa specimens revealed relatively higher mean density ratio for each cytokine investigated than did normal turbinate mucosa. IL-6, IL-8, TGF-beta, IL-4, IL-5, and IFN-gamma mRNAs were expressed simultaneously in maxillary sinus mucosa of chronic sinusitis. These cytokines may be responsible for recruitment of inflammatory cells and for mucosal thickening in chronic sinusitis, and thus chronicity of the disease.

Abnormal expression of the cystic fibrosis transmembrane regulator in chronic sinusitis in cystic fibrosis and non-cystic fibrosis patients

Cystic fibrosis (CF) patients commonly suffer from chronic sinusitis. Mutations of a single gene, the cystic fibrosis transmembrane conductance regulator (CFTR) gene, have been associated with CF. Functional CFTR protein is localized to the apical cell membrane, while dysfunctional CFTR is commonly found in the cytoplasm. We undertook a preliminary immunocytochemical study of CFTR subcellular localization in CF and non-CF pediatric and adult patients using a newly developed murine monoclonal antibody, TAM. Immunostaining was evaluated for subcellular localization (cytoplasmic versus membranous) and for epithelial layer (basal versus luminal). Analysis of the predominant CFTR distribution patterns demonstrated significant differences in adult versus pediatric groups independent of whether the latter were CF or non-CF (p<.0001 and p<.008, respectively), and no significant difference between the 2 pediatric groups (p = .70). This suggests that the pathophysiology of pediatric sinusitis differs from that of adult sinusitis at the level of secretion production.

Inhibitory effect of erythromycin on interleukin-8 secretion from exudative cells in the nasal discharge of patients with chronic sinusitis

OBJECTIVES

The mechanism of the efficacy of long-term low-dose macrolide therapy for chronic sinusitis is not fully understood. The authors studied the inhibitory effect of erythromycin on interleukin-8 (IL-8) secretion from exudative cells in the nasal discharge of patients with chronic sinusitis.

STUDY DESIGN AND METHODS

Exudative cells in the nasal discharge were isolated from six patients with nonallergic chronic sinusitis. The cells, more than 90% of which were neutrophils, were incubated with or without erythromycin in the presence of 10 micrograms/mL of lipopolysaccharide. The IL-8 concentrations in the culture supernatants were measured by enzyme-linked immunoassay.

RESULTS

The amount of secreted IL-8 in the absence of erythromycin was 682 +/- 226 pg/10(6) cells/24 h. The IL-8 secretion was significantly reduced to 66 +/- 15% and 46 +/- 13% of the control in the presence of 10(-6) and 10(-5) M of erythromycin, respectively.

CONCLUSION

Erythromycin may act as a biologic modulator that inhibits IL-8 secretion from exudative cells and thereby blocks the vicious circle of neutrophil recruitment and IL-8 generation in the inflammatory site in chronic sinusitis.

Sinus mucosal IL-8 gene expression in chronic rhinosinusitis

BACKGROUND

Epithelial hyperplasia and mucosal infiltration of leukocytes are common features of chronic rhinosinusitis. The epithelium can produce chemoattractant cytokines that may contribute to leukocyte infiltration in rhinosinusitis.

OBJECTIVE

We sought to determine whether mucosal IL-8 gene expression is increased in chronic rhinosinusitis and to relate IL-8 gene expression to disease severity.

METHODS

We used both a noncompetitive and a quantitative, competitive reverse transcription-polymerase chain reaction to examine IL-8 gene expression in samples of sinus mucosal tissue obtained during surgery from 22 patients with chronic rhinosinusitis and 9 normal control subjects. IL-8 gene expression was related to disease severity assessed by sinus computed tomography (CT) scores and to symptom scores assessed by means of a questionnaire.

RESULTS

Sinus mucosal IL-8 gene expression was not detected in any of the control subjects but was present in 12 of 22 (55%) patients with rhinosinusitis. Sinus CT scores and symptom scores were both significantly higher in patients with positive mucosal IL-8 gene expression than in subjects with no detectable IL-8 gene expression. Positive IL-8 gene expression was not predicted by history of prior surgery nor by atopic or asthmatic status. In 9 subjects with positive IL-8 gene expression, levels of mRNA expression, assessed by competitive reverse transcription-polymerase chain reaction, correlated significantly (rho = 0.72, P <.05) with sinus CT scores.

CONCLUSION

Sinus mucosal expression of the gene for IL-8 is increased in patients with chronic rhinosinusitis, and the level of IL-8 gene expression correlates with disease severity.

Cytokines in nasal polyposis, acute and chronic sinusitis

Cytokines are potent biologic factors involved in the regulation of inflammation, immune defense, and wound healing. Recently, growing interest has developed in the role of cytokines in chronic sinusitis and nasal polyposis. In the present study, we investigated the cytokine profile of different types of rhinosinusitis in order to evaluate whether a specific form of rhinosinusitis is associated with the expression of a certain cytokine profile. Sinus mucosa from patients with acute sinusitis (n = 10), chronic sinusitis (n = 7), antrochoanal polyp (n = 10), nasal polyps (n = 8) and controls of turbinate mucosa (n = 7) were sampled. The cytokine protein content (IL-1 beta, IL-3, IL-4, IL-5, IL-6, IL-8, IL-13, GM-CSF, interferon-gamma) of tissue homogenates was measured using ELISA technique. In acute sinusitis, the synthesis of proinflammatory cytokines and of the neutrophil chemokine IL-8 and IL-3 appeared to be upregulated. Chronic sinusitis mucosa demonstrated no significantly increased concentrations of the measured cytokines. In bilateral nasal polyposis, but not in antrochoanal polyps, the eosinophil related cytokine IL-5 was strongly upregulated. From these findings, it appears that specific cytokine patterns are found in different forms of sinusitis, and that IL-5 may represent the most important cytokine responsible for tissue eosinophilia in nasal polyposis.

Expression of adhesion molecules in cultured human nasal mucosal microvascular endothelial cells activated by interleukin-1 beta or tumor necrosis factor-alpha: effects of dexamethasone

Adhesion molecules of microvascular endothelial cells play a key role in the inflammatory processes involved in nonallergic sinusitis. We investigated the cytokine-regulated expression of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1), and the effect of dexamethasone on these expressions in cultured human nasal microvascular endothelial cells (HNMEC). ICAM-1 was enhanced, and E-selectin and VCAM-1 were induced in a dose-dependent fashion following stimulation with IL-1beta or TNF-alpha. HNMEC differed from human umbilical vein endothelila cells in that (1) maximal upregulation of ICAM-1 expression induced by IL-1beta or TNF-alpha required more time (2) TNF-alpha was more potent than IL-1beta in VCAM-1 expression, and (3) dexamethasone inhibited the upregulation of E-selectin expression alone. These findings contribute to a better understanding of the characteristic features of leukocyte infiltration into inflamed tissue and the effect of glucocorticoid in nonallergic chronic sinusitis.

Inhibitory effect of macrolides on interleukin-8 secretion from cultured human nasal epithelial cells

The mechanism of macrolide therapy in chronic sinusitis patients is unclear. The authors studied the effect of macrolides on interleukin (IL)-8 secretion from cultured human nasal epithelial cells. Epithelial cells harvested from the nasal polyps of patients with chronic sinusitis were primary-cultured, and secreted IL-8 in culture media was measured by enzyme immunoassay. The cells secreted considerable amounts of IL-8 constitutively and in response to lipopolysaccharide. The secretion was significantly inhibited by 10(-5) M of erythromycin, clarithromycin, roxithromycin, and josamycin. 10(-6) M erythromycin still showed the inhibitory effect, whereas the same concentration of josamycin did not. These results indicate that macrolide antibiotics may act as an immunomodulator to reduce IL-8 in inflammatory sites and, at least partially, account for the clinically discrepant effects between 14- and 16-membered ring macrolides in long-term low-dose therapy for chronic sinusitis.

Expression of adhesion molecules in nonallergic chronic sinusitis

Endothelial and epithelial adhesion molecules are important in the recruitment of leukocytes to inflammatory sites. To determine the relationship between recruited leukocytes and adhesion molecules in the paranasal sinus mucosa of nonallergic chronic sinusitis, we surgically obtained mucosa from 16 patients and identified the expression of intercellular adhesion molecules (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and P-selectin by immunohistochemistry. Neutrophils were significantly dominant in the nasal discharge as compared with eosinophils. The degree of neutrophil infiltration in the paranasal sinus mucosa was prominent in both intraepithelial and subepithelial areas as compared with the lamina propria. In each tissue site, the degree of infiltration of neutrophils was similar to that of eosinophils. These findings suggest that the tissue neutrophils actively and rapidly migrated into the lumen. All the adhesion molecules except VCAM-1 were expressed in the vascular endothelial cells. On the other hand, the surface epithelial cells showed the expression of only ICAM-1. The expression of ICAM-1 on the endothelial cells correlated with the degree of neutrophil infiltration in the mucosa The eosinophil infiltration was not dependent on any adhesion molecules examined here. It was concluded that ICAM-1 expression in the mucosa may be involved in neutrophil recruitment and may contribute to the establishment of the inflammatory cell distribution in the paranasal sinus of nonallergic chronic sinusitis.

Effects of long-term low-dose macrolide administration on neutrophil recruitment and IL-8 in the nasal discharge of chronic sinusitis patients

Effects of long-term low-dose macrolide administration were studied in patients with chronic sinusitis. Twelve patients with non-allergic chronic sinusitis were orally given 150 mg roxithromycin once a day without other treatments. The patients underwent computed tomography before and after the treatment, and paranasal sinus aeration was analyzed quantitatively. The number of neutrophils in the nasal smear was semiquantitatively assessed on a grading scale, and the IL-8 concentration in the nasal discharge was measured by enzyme immunoassay. The aeration of all four sinuses significantly improved, and recruited neutrophils and the IL-8 level in the nasal discharge were simultaneously reduced after the treatment. These findings suggest that long-term low-dose roxithromycin administration inhibits the positive feedback mechanism of neutrophil recruitment and IL-8 production by the recruited neutrophils, which is considered to be an essential cause of the prolongation of sinusitis.

Influence of age on the production of interleukin-8-like chemokine (GRO/CINC-1) in rat nasal mucosa

The ability of the nasal mucosa to produce various cytokines has been shown to correlate closely with the capacity to regulate an inflammatory condition in the nasal cavity. Immune senescence is characterized by a dysregulation of the immune system. This change is reflected by the altered production of cytokines during aging. We measured the in vivo production and gene expression of IL-8-like cytokines (GRO/CINC-1) in nasal lavages and mucosa from young (2- to 4-week-old and 11- to 15-week-old) and older (81-to 98-week-old) rats by using enzyme-linked immunosorbent assays and reverse transcription-polymerase chain reactions. Significant increases of GRO/CINC-1 levels were found in unstimulated nasal lavages of the older rats compared to that of the 2- to 4-week-old animals. GRO/CINC-1 showed time-dependent production with lipopolysaccharide (LPS) stimulation in nasal lavages. The GRO/CINC-1 production reached a plateau by 4 h with LPS in any group. However, the manner of the initial time course showed no significant differences among these three groups. At the time of peak production of GRO/CINC-1, messenger RNA for the GRO/CINC-1 was found to be induced in the nasal mucosa. These findings may be important for understanding the mechanisms of the altered immune response and inflammation in the nasal cavity associated with aging.

Production and gene expression of IL-8-like cytokine GRO/CINC-1 in rat nasal mucosa

Growth-regulated gene product/cytokine-induced neutrophil chemoattractant (GRO/CINC)-1 is a rat chemokine with structural and functional homology to human IL-8. Chemokines are a family of cytokines whose participation in nasal inflammation in vivo remains to be established. Using ELISA and RT-PCR, we investigated the production and gene expression of GRO/CINC-1 in rat nasal lavage and mucosa in vivo. GRO/CINC-1 in nasal lavage was produced by stimulation of LPS, ConA and IL1-beta. GRO/CINC-1 showed time- and dose-dependent production under all stimulants, but was more slowly induced by IL-1 beta. The steady-peak of the GRO/CINC-1 production remained at 3 h with LPS or ConA exposure, whereas it lasted 4 h or more after IL-1 beta exposure. At the time of peak production of GRO/CINC-1, we found that mRNA for the GRO/CINC-1 was induced in the nasal mucosa. The mRNA of the related inflammatory cytokines TNF-alpha and IFN-gamma were also expressed in nasal mucosa with stimulation of these reagents. Thus, this study revealed that exposure to bacterial endotoxin, mitogenic reagent and also IL-1 beta induced the production and gene expression of the neutrophil chemoattractant GRO/CINC-1 in rat nasal mucosa in vivo. This investigation of the characteristics of IL-8 family in nasal mucosa using rat models has extended the functional concept of cytokines in the inflammatory condition of nasal cavity in humans.

Mechanism of neutrophil recruitment induced by IL-8 in chronic sinusitis

BACKGROUND

The mechanism of neutrophil recruitment in patients with chronic sinusitis is unclear.

OBJECTIVE

This study aims to elucidate the role of IL-8 in inducing neutrophil accumulation in the nasal discharge of patients with chronic sinusitis.

METHODS

Nasal discharge and mucosal specimens were obtained from two groups of patients, those with chronic sinusitis and those with allergic rhinitis. The samples were subjected to immunohistochemical examination and in situ hybridization. The IL-8 level in the nasal discharge was measured by enzyme immunoassay.

RESULTS

Immunoreactivity to IL-8 was observed in polymorphonuclear cells of nasal smear, in nasal gland duct cells, and in epithelial cells of the chronic sinusitis group; whereas those of the allergic rhinitis group mostly showed little or no reaction. Similar patterns of localization were shown by in situ hybridization for IL-8 messenger RNA. The IL-8 level in nasal discharge was significantly higher in the chronic sinusitis group than in the allergic rhinitis group.

CONCLUSION

These results suggest that chemotactic factors in sinus effusion, including IL-8 derived from nasal gland duct cells and epithelial cells, attract neutrophils out of mucosa, and the neutrophils that have emigrated into the sinus effusion secrete IL-8. This induces further neutrophil accumulation in the sinus effusion of patients with chronic sinusitis.