Cell and cytokine profiles in nasal secretions from patients with nasal polyposis: effects of topical steroids and surgical treatment

TLR-2 expression and dysregulated human Treg/Th17 phenotype in Aspergillus flavus infected patients of chronic rhinosinusitis with nasal polyposis

Background

T helper (Th)17 and regulatory T (Treg) cells with toll-like receptor (TLR)-2 have been acknowledged to play a critical role in chronic rhinosinusitis with nasal polyposis (CRSwNP). However, its pathogenesis has been perplexed by conflicting reports on the role of Th17/Treg cells in patients of distinct ethnicities. We attempted to understand the role of Th responses induced during host defense against Aspergillus flavus.

Results

The percentages of Th17 (CD4⁺CD161⁺IL23R⁺) and Treg (CD4⁺CD25⁺FoxP3⁺) cell populations and various cytokine profiles in peripheral blood mononuclear cells (PBMCs) challenged by A. flavus antigens were characterized from 50 CRSwNP cases, before and after treatment, and in 50 healthy controls. TLR-2 expression was analyzed in tissues of cases and controls for disease co-relation. The major pathogen identified in our study was A. flavus by mycological investigations. A marked immune imbalance was noted with elevated Th17 and decreased Tregs in PBMCs of CRSwNP patients after A. flavus stimulation. Comparatively, interleukin (IL)-17 and IL-10 levels were increased, with low transforming growth factor (TGF)-β levels in A. flavus stimulated PBMC supernatants of patients. The mRNA expression of TLR-2 in polyps of CRSwNP patients indicated significant (p = 0.001) upregulation in comparison to the controls.

Conclusions

Our data highlights the excessive expression of TLR-2 in nasal polyps contributing to the imbalance in Th17/Tregs population in patients. After therapy, recovery of Tregs cells indicates restoration and tissue homeostasis, though high circulating CD4⁺CD161⁺ Th17 cells may continue to be a threat to patients predisposed to future recurrences. The constant exposure and tendency of A. flavus to colonize nasal cavities can lead to a Th17 driven airway inflammation. Dysregulated Th17 with TLR-2 promote resistance to treatment and progression to the chronicity of the disease.

Mir-142-3p Regulates Inflammatory Response by Contributing to Increased TNF-α in Chronic Rhinosinusitis With Nasal Polyposis

Objective:

Previous studies suggested that microRNAs played an important role in the progression of inflammation and remodeling of chronic rhinosinusitis with nasal polyposis. However, the abnormal expression of microRNAs and regulation cytokine expression in nasal polyposis are not clear.

Method:

The miR-142-3p and tumor necrosis factor α (TNF-α) expression levels in chronic rhinosinusitis with nasal polyposis were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The miR-142-3p and TNF-α levels in human nasal epithelial cells (HNEpC) after stimulation by lipopolysaccharide (LPS) were detected by qRT-PCR. Moreover, HNEpCs were transfected by miR-142-3p mimics or inhibitor or cotransfected with si-TNF-α to evaluate the regulation of miR-142-3p on TNF-α which affects the production of inflammatory factors.

Results:

The miR-142-3p and TNF-α were significantly higher in nasal mucosa of chronic rhinosinusitis with polyps patients compared to normal human. MiR-142-3p and TNF-α expression levels were increased after LPS stimulation in a dose- and time-dependent manner. Knockdown of miR-142-3p in HNEpCs downregulated TNF-α expression at both messenger RNA and protein levels.

Conclusions:

It is indicated that miR-142-3p may participate in the regulation of the body’s inflammatory response through the LPS-TLR-TNF-α signaling pathway in chronic rhinosinusitis with nasal polyposis.

Comparison of Corticosteroids by 3 Approaches to the Treatment of Chronic Rhinosinusitis With Nasal Polyps

Purpose

Corticosteroids are regarded as the mainstay of medical treatment of eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP). To date, a head-to-head comparison of the efficacy and safety of glucocorticoid preparations administered via different routes for the treatment of chronic rhinosinusitis with nasal polyps has not been reported. To compare the efficacy and safety of steroids administered via the oral, intranasal spray and transnasal nebulization routes in the management of ECRSwNP over a short course.

Methods

Overall, 91 patients with ECRSwNP were recruited prospectively and randomized to receive either oral methylprednisolone, budesonide inhalation suspension (BIS) via transnasal nebulization, or budesonide nasal spray (BNS) for 2 weeks. Nasal symptoms and polyp sizes were assessed before and after the treatment. Similarly, nasal polyp samples were evaluated for immunological and tissue remodeling markers. Serum cortisol levels were assessed as a safety outcome.

Results

Oral methylprednisolone and BIS decreased symptoms and polyp sizes to a significantly greater extent from baseline (P < 0.05) than BNS. Similarly, BIS and oral methylprednisolone significantly reduced eosinophils, T helper 2 cells, eosinophil cationic protein, interleukin (IL)-5, and expression of matrix metalloproteinases 2 and 9, and significantly increased type 1 regulatory T cells, IL-10, transforming growth factor-β, and tissue inhibitor of metalloproteinases 1 and 2 in nasal polyps to a greater extent than BNS. Post-treatment serum cortisol levels were significantly decreased by oral methylprednisolone compared to BIS or BNS, which did not significantly alter the cortisol levels.

Conclusions

A short course of BIS transnasal nebulization is more efficacious compared to BNS in the management of ECRSwNP and is safer than oral methylprednisolone with respect to hypothalamic-pituitary-adrenal axis function.

Immunopathogenesis of Chronic Rhinosinusitis and Nasal Polyposis

Chronic rhinosinusitis (CRS) is a troublesome, chronic inflammatory disease that affects over 10% of the adult population, causing decreased quality of life, lost productivity, and lost time at work and leading to more than a million surgical interventions annually worldwide. The nose, paranasal sinuses, and associated lymphoid tissues play important roles in homeostasis and immunity, and CRS significantly impairs these normal functions. Pathogenic mechanisms of CRS have recently become the focus of intense investigations worldwide, and significant progress has been made. The two main forms of CRS that have been long recognized, with and without nasal polyps, are each now known to be heterogeneous, based on underlying mechanism, geographical location, and race. Loss of the immune barrier, including increased permeability of mucosal epithelium and reduced production of important antimicrobial substances and responses, is a common feature of many forms of CRS. One form of CRS with polyps found worldwide is driven by the cytokines IL-5 and IL-13 coming from Th2 cells, type 2 innate lymphoid cells, and probably mast cells. Type 2 cytokines activate inflammatory cells that are implicated in the pathogenic mechanism, including mast cells, basophils, and eosinophils. New classes of biological drugs that block the production or action of these cytokines are making important inroads toward new treatment paradigms in polypoid CRS.

Lymphocyte Subpopulations and Cytokines in Nasal Polyps: Is there a Local Immune System in the Nasal Polyp?

PURPOSE: The pathogenesis of chronic hyperplastic rhinosinusitis with massive nasal polyposis is still not entirely known. The present study evaluates the lymphocyte subpopulations and their production of cytokines using a technique for detection of intracytoplasmic cytokines by flow cytometry. This information may allow us to determine whether the source of these lymphocytes is from peripheral blood, the common mucosal immune system, or both.

METHODS: Detection of intracytoplasmic cytokines by flow cytometry was performed using a fluoresceinated monoclonal antibody directed against CD4+ and CD8+ lymphocytes and a rhodaminelabeled intracytoplasmic monoclonal antibody directed against four cytokines. In this way, the percentage of lymphocytes synthesizing TH1 and TH2 cytokines were identified in nasal polyp lymphocytes and the corresponding peripheral blood lymphocytes of 13 patients.

RESULTS: Lymphocytes producing interferongamma and IL-2, as well as IL-4 and IL-5, were found in the nasal polyps, suggesting that the nasal polyp possesses both TH1 and TH2 cytokine expression. There are also significant differences between the percentage of lymphocytes producing these cytokines between nasal polyps and peripheral blood, suggesting that nasal polyp lymphocytes derive from at least another source than only peripheral blood lymphocytes. Statistical analysis of four groups of patients demonstrated that no statistically significant difference in the lymphocyte subpopulations in atopic versus non-atopic patients, nor aspirin-intolerant versus aspirin-tolerant patients. In general, CD8 cells always produce more interferon-gamma than IL-2 in both peripheral blood and nasal polyps. In contrast with this data, CD4 cells produce more IL-2 in the peripheral blood than in nasal polyps.

CONCLUSIONS: Data support the concept that nasal polyp lymphocyte subpopulations may be derived from both the local mucosal immune system as well as from random migration of peripheral blood lymphocytes secondary to adhesion molecules and chemokines, which are known to be present in nasal polyps.

Correlation between cytokine levels in nasal fluid and eosinophil counts in nasal polyp tissue in asthmatic and non-asthmatic patients

BACKGROUND/AIMS

Concentrations of mediators in nasal secretions could reflect the inflammatory status of the nasal mucosa and evolution of sinus disease. So, the aim of our study was to evaluate local immune reaction by measuring crucial Th1, Th2 and inflammatory cytokines in nasal fluid samples of patients with nasal polyps (NP), and to correlate them to clinical, radiological findings and to the degree of eosinophil infiltration of polyp tissue. Therefore, in our study we compared the cytokine levels in nasal fluid of asthmatic and non-asthmatic patients with nasal polyposis, the eosinophil counts in NP tissues of these patients, and we correlated cytokine levels with eosinophil counts in NP tissue specimens.

MATERIAL AND METHODS

Thirty patients with nasal polyposis (NP) (15 asthmatic and 15 non-asthmatic) were included in this prospective study. Nasal secretion samples were collected from nasal cavities of all subjects. The levels of 11 cytokines (TNF-α, TNF-β, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, and IFN-γ) were measured using commercial flow cytometric kit. Eosinophils were counted in haematoxylin-and-eosin-stained NP sections.

RESULTS

The concentrations of Th2 cytokines IL-5, IL-6, IL-10, and Th1 cytokine IFN-γ were significantly higher in patients with NP and asthma compared with non-asthmatic subjects. A positive correlation was found between IL-6 and TNF-α levels in nasal fluid and eosinophil counts in polyp tissue in non-asthmatic subjects. In asthmatic NP patients, we found positive correlation between level of IL-6 and eosinophil counts and negative correlation between IFN-γ level and number of eosinophils in NP tissue specimens.

CONCLUSION

Our results showed that these patients with similar clinical findings had significantly different mediator profiles in their nasal secretions, implying clear differences in pathogenesis of their NP.

Short-term antibiotics treatment in patients with nasal polyps and enterotoxins producing Staphylococcus aureus strains

Enterotoxins produced by Staphylococcus aureus (SA) can act as super-antigens and thus influence the course of chronic rhinosinusitis with nasal polyps (NP). The aim of this study was to determine if antibiotic treatment administered after endoscopic sinus surgery (ESS) for NP can positively influence the course of the disease compared to placebo. After ESS, 23 patients who tested positive, in a perioperative culture, for SA strains producing enterotoxins A-E and TSST-1, were randomized into two groups. Group A which in addition to standard treatment received oral anti-staphylococcal antibiotics for 3 weeks. Group B received a placebo. Both groups were compared preoperatively, and at 3 and 6 months after surgery using a symptom-specific score, an endoscopic score and the SNOT-22 quality of life questionnaire. Slightly better results were achieved in patients who received antibiotic therapy. However, the differences were not statistically significant. Regardless of post-operative treatment, approximately 30% of patients had a SA-negative culture 6 months after surgery.

Connectivity can be used to identify key genes in DNA microarray data: a study based on gene expression in nasal polyps before and after treatment with glucocorticoids

CONCLUSIONS

The presented analysis of nasal polyposis using connectivity based on the PubGene literature co-citation network demonstrates that this tool can be used to identify key genes in DNA microarray studies of human polygenic diseases.

OBJECTIVES

DNA microarray studies of complex diseases may reveal differential expression of hundreds of genes. According to network theory and studies of yeast cells, genes that are connected with several other genes appear to have key regulatory roles. This study aimed to examine if this principle can be translated to DNA microarray studies of human disease, using nasal polyposis as a base for the analysis.

MATERIALS AND METHODS

The connectivity of differentially expressed genes from a previously described microarray study of nasal polyposis before and after treatment with glucocorticoids was determined. This was done using the literature co-citation network PubGene.

RESULTS

In all, 166 genes were differentially expressed; 39 of these were previously defined as inflammatory and considered important for nasal polyposis. The connectivity of all differentially expressed genes was analysed using the PubGene literature co-citation network. Seventy-four of the 166 genes were connected to other genes. By contrast, the average number of connected genes among 100 sets of 166 randomly chosen genes was 31.5. A small number of the differentially expressed genes were highly connected, while most genes had few or no connections. This indicated a scale-free network. The most connected gene was interleukin-8, an inflammatory gene of known importance for nasal polyposis. Twenty-eight of the 74 connected genes were inflammatory (38%), compared with 11 of the 92 unconnected genes (12%), p < 0.0001. Since most evidence suggests that nasal polyps are inflammatory in their nature, this supports the hypothesis that connected genes have more disease relevance than unconnected genes.

Relationship between matrix metalloproteinases MMP-2, MMP-9, tissue inhibitor of matrix metalloproteinases-1 and IL-5, IL-8 in nasal polyps

BACKGROUND

Nasal polyps (NP), a subgroup of chronic rhinosinusitis, are characterized by interleukin 5 (IL-5) mediated infiltration of eosinophils in sinus mucosa, leading to pseudostratified ciliated columnar epithelium, thickening of the epithelial basement membrane and tissue edema. Matrix metalloproteinases (MMP) constitute a large group of Zn2+ dependent endopeptidases with the ability to degrade extracellular matrix and are possibly responsible for the development of tissue edema in chronic sinusitis.

OBJECTIVE

The aim of this study was to determine the expression of MMP-2, MMP-9 and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) mRNA and to locate the distribution of MMP-2, MMP-9 and TIMP-1 by immunohistochemistry in ethmoid sinus mucosa in NP. Furthermore the correlation between IL-5 or IL-8 and MMP-2, MMP-9 or TIMP-1 is examined.

METHODS

Nasal polyps of 33 patients and 18 specimens of inferior turbinate mucosa were examined by real time RT-PCR for MMP-2, MMP-9, TIMP-1, IL-5 and IL-8 mRNA expression. Immunohistochemical labeling for MMP-2, MMP-9 and TIMP-1 was performed.

RESULTS

Differences between both locations were detectable for MMP-9 (P < 0.001) and IL-5 (P=0.003) but not for MMP-2 (P=0.278), TIMP-1 (P=0.515) and IL-8 (P=0.386). Correlation was detected only between TIMP-1 and IL-5 (r=0.422, P =0.014). Cytoplasmic staining of MMP-2 was present in the apical part of the ciliated cells, submucosal glands and in smooth muscle cells. Matrix metalloproteinase-9 was expressed in surface epithelium, in seromucous glands and in polymorphonuclear cells.

CONCLUSIONS

Expression of MMP-9 and IL-5 mRNA are associated with NP. The correlation between IL-5 and TIMP-1 indicates the role of TIMP-1 in maintaining the homeostasis in NP.

Nasal polyp diseases in allergic and nonallergic patients and steroid therapy

OBJECTIVE

To investigate widespread disease causes, cellular-structural differences, and steroid response of nasal polyps (NPs).

METHOD

Study group consisted of NPs, allergic-NPs, NPs with steroid therapy (ST), antrochoanal polyp (ACP), and controls. We investigated stromal eosinophil, mast cell, CD4+ and CD8+ cell counts and presence of squamous metaplasia, Ki-67 expression, intraepithelial eosinophils-mast cells, epithelial damage, edema, fibrosis, hyalinization, polymorphonuclear leukocyte, and glandular hyperplasia.

RESULTS

In allergic-NPs, intraepithelial eosinophils and epithelial damage CD4+ were significantly higher than NPs and also, eosinophils, mast cells, intraepithelial eosinophils, and epithelial damage were significantly higher than ACP. Only stromal eosinophilic infiltration was significantly higher in NPs than ACP. There was significant increased glandular hyperplasia and decreased intraepithelial eosinophils, mast cells, CD4+ cells, squamous metaplasia, and epithelial damage with ST in allergic-NPs. There were no significant differences with ST in NPs.

CONCLUSION

NPs in allergic and nonallergic patients may differ in their histology and in their histologic responses to ST.

EBM RATING

B-3b.

TNF-alpha upregulates VCAM-1 and NF-kappaB in fibroblasts from nasal polyps

OBJECTIVE

Lung and synovial fibroblasts produce VCAM-1 in response to TNF-alpha. However, the massive infiltration of eosinophils, the effects of the increased amount of TNF-alpha and the production of VCAM-1 in human nasal polyp fibroblasts are not yet fully understood. The present study examines the role of VCAM-1 and the molecular mechanism of its expression in nasal fibroblasts.

METHODS

Nasal fibroblasts were isolated from human nasal polyps and after four passages, the cells were stimulated with TNF-alpha and VCAM-1 expression was examined by ELISA, flow cytometry, and RT-PCR. The activation of NF-kappaB induced by TNF-alpha was determined by electrophoretic mobility shift assays and the influence on the expression of VCAM-1 was investigated.

RESULTS

VCAM-1 protein and mRNA were expressed in unstimulated controls and remarkably increased by TNF-alpha stimulation. NF-kappaB activity was enhanced by TNF-alpha stimulation and remarkably suppressed by NF-kappaB proteasome inhibitor.

CONCLUSIONS

The present study discovered that nasal fibroblasts produce VCAM-1 protein and mRNA and that production is increased by TNF-alpha stimulation. Furthermore, VCAM-1 expression in nasal fibroblasts is induced through an NF-kappaB-dependent pathway. These findings might provide a rationale for using NF-kappaB inhibitors as a treatment for nasal inflammatory diseases such as polyps.

Potential New Avenues of Treatment for Chronic Rhinosinusitis: an Anti-inflammatory Approach

Chronic rhinosinusitis is a complex disease process, one that is characterized by much more than just infection. Until its pathophysiology is understood fully, truly definitive therapy may remain elusive. As this underlying inflammatory process begins to unravel, however, new avenues of therapy will begin to emerge. This article discusses some of these new therapies and provides some clues as to where future avenues may go.

Inflammatory mediators and eosinophilia in atopic and non-atopic patients with nasal polyposis

Nasal polyps are characterized by eosinophilic infiltration and presence of inflammatory mediators, such as total IgE, eosinophil cationic protein (ECP) and cytokines. The role of atopy in nasal polyp pathogenesis is still unclear. Therefore, we evaluated serum IgE levels, nasal mucus concentrations of ECP and cytokines and the number of infiltrating eosinophils in nasal tissue of polyps from atopic and non-atopic patients. Samples were obtained from a randomized population of 31 patients with nasal polyposis having endonasal sinus surgery and of 13 control subjects undergone corrective surgery of the nasal septum. On the basis of medical history of allergy, positive skin-prick tests and total IgE levels, patients with polyposis were divided in atopic (n = 13) and non-atopic (n = 18) patients. We determined levels of IgE in blood, ECP and cytokines (IL-4, IL-6, IL-8, IFN-gamma and IL-2) in nasal mucus, and number of infiltrating eosinophils in nasal tissue. The concentrations of total IgE, ECP, IL-4 and IL-8 and eosinophilia were significantly higher in all patients with nasal polyps compared with controls. Inside, all patients with nasal polyposis showed lower levels of IL-6, IFN-gamma and IL-2 compared with controls. The atopic patients showed significant differences when compared with non-atopic patients for the higher concentrations of total IgE (698.80+/-322.24 vs. 279.63+/-234.11; P < 0.0001) and IL-8 (1437.2 pg/ml+/-1250.7 vs. 605.5 pg/ml+/-481.1; P < 0.015). These findings suggest that inflammation still remains the major factor in the etiology of nasal polyposis and show different levels of inflammatory mediators into atopic and non-atopic patients.

TNF-alpha and endotoxin increase hypoxia-induced VEGF production by cultured human nasal fibroblasts in synergistic fashion

OBJECTIVE

Vascular endothelial growth factor (VEGF) promotes angiogenesis and is associated with the invasion and metastasis of malignant tumors. It enhances vascular permeability and is expressed in inflammatory nasal as well as middle-ear mucosa. As the mechanism of VEGF induction during chronic inflammation, such as chronic paranasal sinusitis (CPS) remains to be clarified, we studied the factors regulating the production of VEGF in cultured human nasal fibroblasts and discussed the role of VEGF in the pathogenesis of CPS.

METHODS

We used ELISA to quantify VEGF levels in paranasal sinus effusions, nasal secretions, and serum from patients with CPS. In addition, we cultured human nasal fibroblasts isolated from nasal polyps of CPS patients and studied the effects of hypoxia, TNF-alpha, and endotoxin on their production of VEGF using ELISA and PCR.

RESULTS

The VEGF concentration was significantly higher in paranasal sinus effusions than in nasal secretions and serum. Nasal fibroblasts produced high levels of VEGF, when cultured under hypoxic condition and this production was remarkably enhanced in the presence of TNF-alpha or endotoxin.

CONCLUSION

VEGF is locally produced in paranasal sinuses as well as nasal mucosa and its production is increased in patients with CPS. Hypoxia is associated with the production of VEGF by nasal fibroblasts and TNF-alpha and endotoxin may act synergistically to enhance VEGF production in paranasal sinuses under hypoxic condition.

Antifungal immune reactivity in nasal polyposis

As a fungal etiology has been proposed to underlie severe nasal polyposis, the present study was undertaken to assess local antifungal immune reactivity in nasal polyposis. For this purpose, microbial colonization, along with the pattern of T helper 1 (Th1)/Th2 cytokine production and Toll-like receptor (TLR) expression, was evaluated in patients with nasal symptoms and with and without polyposis and in healthy subjects. The results show that Th2 reactivity was a common finding for patients with nasal polyposis regardless of the presence of microbes. The production of interleukin-10 was elevated in patients with bacterial and, particularly, fungal colonization, while both TLR2 expression and TLR4 expression were locally impaired in microbe-colonized patients. Eosinophils and neutrophils, highly recruited in nasal polyposis, were found to exert potent antifungal effector activities toward conidia and hyphae of the fungus and to be positively regulated by TLR2 or TLR4 stimulation. Therefore, a local imbalance between activating and deactivating signals to effector cells may likely contribute to fungal pathogenicity and the expression of local immune reactivity in nasal polyposis.

Cell and cytokine profile in nasal secretions in cystic fibrosis

BACKGROUND

Nasal polyposis (NP) frequently complicates the course of cystic fibrosis (CF). The aim of this study was to determine the pattern of inflammatory cells and mediators in nasal secretions from patients with or without NP compared to patients with idiopathic NP and healthy controls.

METHODS

Eighteen CF patients with NP (NP+ group: 6 untreated, 12 treated with nasal steroids), and 15 without NP (NP- group) were included in this prospective study and compared to 9 patients with idiopathic NP and 12 healthy controls. Differential cell count eosinophil cationic protein (ECP), interleukin-5 (IL-5) and IL-8 were determined in nasal lavage fluids.

RESULTS

The total cell count, the number and the percentage of neutrophils and eosinophils, the levels of IL-8, IL-5 and ECP were significantly higher in nasal secretions from both NP+ and NP- as compared with controls. No difference was found between untreated and treated CF patients with NP. No difference was found between NP+ and NP- groups. Compared to idiopathic NP group, both NP+ and NP- groups had higher percentage of neutrophils and lower percentage of eosinophils. There were no differences according to the use of topical steroids, systemic antibiotherapy, or the type of mutation. CF patients with positive nasal culture had a higher percentage of neutrophils than those with negative culture. CF patients with atopy had a higher percentage of eosinophils than non-atopic patients.

CONCLUSION

Our results demonstrate that nasal inflammation is a prominent feature in patients with CF and does not differ according to the presence of NP. IL-8 and IL-5 may play crucial roles in recruitment and activation of neutrophils and eosinophils in upper airways of CF patients.

Suppression of matrix metalloproteinase production from nasal fibroblasts by fluticasone propionate in vitro

OBJECTIVE

To examine the influence of fluticasone propionate (FP) on matrix metalloproteinase (MMP) production from nasal polyp fibroblasts in vitro.

MATERIAL AND METHODS

Fibroblasts derived from five nasal polyps were stimulated with tumor necrosis factor (TNF)-alpha in the presence of various concentrations of FP. The influence of FP on MMP production was assessed by examining the levels of MMP-2 and -9 in culture supernatants using ELISA. We also examined the influence of FP on MMP mRNA expression using reverse transcriptase polymerase chain reaction.

RESULTS

The addition of FP caused significant suppression of MMP-2 and -9 production from nasal polyp fibroblasts in response to TNF-alpha stimulation. MMP mRNA expression was also suppressed by the addition of FP to cell cultures. The minimum concentration of the agent required to cause suppression was 10(-5) M.

CONCLUSION

These results suggest that the inhibitory action of FP on tissue remodeling may underlie the clinical efficacy of corticosteroids in nasal polyposis.

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.

Induction of apoptosis in nasal polyp fibroblasts by glucocorticoids in vitro

OBJECTIVE

To examine the possible mechanisms underlying the therapeutic mode of action of glucocorticoids (GCs) in nasal polyposis.

MATERIAL AND METHODS

The effects of GCs on nasal polyps were firstly evaluated by examining the growth of fibroblasts derived from 10 nasal polyps in vitro. Subsequently, the ability of GCs to induce apoptotic cell death in fibroblasts was examined.

RESULTS

Addition of betamethasone 21-phosphate (BET) at a concentration of > 1 x 10(-3) M to cell cultures inhibited cell growth in all cases examined. BET and dexamethasone 21-phosphate, but not testosterone or estradiol, caused apoptotic cell death in 2/10 nasal polyp fibroblasts, as assessed by agarose gel electrophoresis, when the cells were cultured with the agents for > 96 h. The minimum concentration of agent needed to cause apoptosis was 1 x 10(-3) M, which is half of the recommended therapeutic dose.

CONCLUSION

The present findings suggest that topical application of GCs in nasal polyposis patients suppresses proliferation of fibroblasts in polyps and results in favorable modification of the clinical status of these patients.