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.

Role of interferon-γ-producing t cells in the pathogenesis of chronic rhinosinusitis with nasal polyps associated with staphylococcal superantigen

OBJECTIVES

The major aims of this study were to characterize the varieties of T-cell infiltrates in tissue collected from patients with chronic rhinosinusitis with nasal polyps (CRSwNP), analyze the cytokine profiles of these infiltrating T cells, and determine whether infiltrating T lymphocytes are specific for superantigens (SAGs).

METHODS

Anterior ethmoid sinus mucosa and polyp tissue were collected from 23 patients with CRSwNP, and control anterior ethmoid sinus mucosa were obtained from 20 patients without CRS. Infiltrating cells were isolated from tissue samples and analyzed using flow cytometry, enzyme-linked immunosorbent assay, reverse transcriptase-polymerase chain reaction, and in vitro T-lymphocyte stimulation with Staphylococcus aureus.

RESULTS

The mean total numbers and proportions of CD3+, CD4+, and CD8+ T cells were significantly higher in the mucosa and polyp tissue of patients with CRSwNP than in the control group. Most infiltrating T cells in patients with CRSwNP were activated CD45RO+ memory T cells. Furthermore, interferon-γ (IFN-γ) expression was significantly higher than interleukin (IL)-10 and IL-4 expression in infiltrating T cells isolated from both the mucosa and the polyp tissue. IFN-γ also showed significantly greater increases in expression compared to IL-4 and IL-10 when isolated T cells were stimulated with SAGs in vitro.

CONCLUSION

IFN-γ-producing T cells could play an important role in CRSwNP when sinonasal chronic inflammation is induced by SAGs.

Eosinophilic chronic rhinosinusitis in Japan

Chronic rhinosinusitis is a heterogeneous disease. In Europe and the United States, it has recently been divided into two subgroups: chronic rhinosinusitis with nasal polyps (CRSwNP) and chronic rhinosinusitis without nasal polyps (CRSsNP). The majority of CRSwNP cases have a strong tendency to recur after surgery and show eosinophil-dominant inflammation. However, this definition has proved difficult to apply in Japan and East Asia, because more than half of the CRSwNP cases do not exhibit eosinophil-dominant inflammation in these areas of the world. In Japan in the 1990s, refractory CRSwNP to the standard treatment was focused on in clinical studies and the term "eosinophilic chronic rhinosinusitis" (ECRS) was introduced to identify this subgroup of chronic rhinosinusitis in 2001. ECRS is different from non-ECRS in terms of many clinical features: symptom appearance, occurrence site of nasal polyps, CT scan findings, the histology of nasal polyps, blood examination findings, clinical course after surgery, and co-morbid asthma, etc. In this review, we describe these clinical features and mention how to make a clinical diagnosis of ECRS as well as how to treat it. Finally, we discuss the pathophysiology of ECRS. The concept of ECRS in Japan would be applicable for CRSwNP in other countries including Europe and the United States.

Pathological mechanisms and clinical features of eosinophilic chronic rhinosinusitis in the Japanese population

The overall pathological view of paranasal sinus inflammation in the Japanese population has profoundly changed in recent years. Eosinophilic chronic rhinosinusitis (ECRS) is a clinical entity of intractable chronic sinus inflammation accompanied by numerous infiltrations of activated eosinophils in the paranasal sinus mucosa and/or nasal polyps. Several pathologic processes are considered to act in concert to promote the accumulation of eosinophils in ECRS. They include infiltration of progenitor cells, increase in local IL-3, IL-5, IL-13, GM-CSF and eotaxin production, and upregulation of adhesion molecules. The role of nasal allergen sensitization and innate immunity responses in the sinus mucosa has also been proposed in the development of ECRS. Various pathogens including TLRs ligands may trigger an abnormal immune response at the mucosal surface. The objectives of ECRS management should focus directly on inhibition of local eosinophil infiltration. Surgical procedures include widely opening the bony wall septum of every affected sinus and mechanical removal of diseased mucosal lesion. The use of local and/or systemic steroids, leukotriene receptor antagonists, and Th2 cytokine antagonists is recommended. Local administration of steroids is a potent treatment strategy for preventing relapse of nasal polyposis and is considered to be the first-line treatment for ECRS patients.

Autologous serum skin test reactivity and basophil histamine release test in patients with nasal polyposis: preliminary results

An eosinophilic inflammatory process is generally observed in patients suffering from nasal polyposis (NP), however its onset has not yet been defined. It has been suggested that immune activation of inflammatory cells may be the cause. The aim of this study is to verify whether autoantibodies and/or histamine-releasing factors are present in the serum of patients suffering from NP. In fact, we assume that autoantibodies and/or histamine-releasing factors, as already demonstrated in chronic idiopathic urticaria and asthma, may be involved in the pathogenesis of NP. In this case-control analytical study 40 patients with NP and 27 control subjects underwent the in vivo autologous serum skin test (ASST). The sera from 6 patients suffering from NP and 9 control group subjects, who had all been previously studied and randomly selected, underwent basophil histamine release assay from normal donor as a pilot study. The ASST showed positive results in 55% of patients suffering from NP versus 8% of the control group (p= .00006), the basophil histamine release test (BHRT) turned out positive in all patients tested and in 11% of the control group. We found a weak positive correlation between the percentage of histamine release and the wheal diameter. ASST reactivity is very frequent in patients suffering from NP, thus suggesting the presence of histamine-releasing factors in the blood stream. The BHRT was positive in the serum of all patients, thus suggesting the presence of anti-FcepsilonRI, anti-IgE autoantibodies and/or other histamine-releasing factors, the presence of which can play a role in triggering and maintaining the eosinophilic inflammatory process in NP.

Analysis of Ki-67 immunoreactivity in recurring and nonrecurring nasal polyps

OBJECTIVE

Nasal polyps are common, abnormal lesions. Recurrence of the nasal polyposis is prevalent and a severe problem. The aim of this study was to investigate the relationship between Ki-67 immunoreactivity and the risk of recurrence of nasal polyps. Ki-67 staining of polypectomy material was tested as a risk factor for recurrence independent of etiologic factors or treatment modalities.

DESIGN

Retrospective study.

SETTING

University hospital.

MAIN OUTCOME MEASURE

Ki-67 immunoreactivity.

METHODS

Pathologic specimens from patients with nonrecurrent and recurrent nasal polyps archived at the Department of Pathology were reviewed, and the most suitable blocks were chosen among the excision materials. Ki-67 antibody staining was investigated immunohistochemically using the avidin-biotin-peroxidase method. The percentages of nuclei immunostained for Ki-67 of at least 1000 epithelial cells in the most intensive staining areas at final magnification (x400) were calculated and defined as the labeling index. The Mann-Whitney U-test was used to compare the Ki-67 labeling index in the nonrecurring and recurring nasal polyp groups.

RESULTS

The mean Ki-67 labeling index was 1.4 +/- 1.972 (range 1-87 in 1000 epithelial cells) in the nonrecurrent nasal polyp group and 17.8 +/- 5.67 (range 82-446 in 1000 epithelial cells) in the recurrent nasal polyp group; the difference between the nonrecurrent and the recurrent group was significant (p < .01).

CONCLUSION

The results of this study clearly demonstrate that proliferative activity in the surface epithelial cells of recurring nasal polyps is significantly higher than that in nonrecurring nasal polyps.

Role of muscarinic receptor activation in regulating immune cell activity in nasal mucosa

BACKGROUND

The prevalence of airway inflammatory disorders keeps rising; its pathogenic mechanism is still not fully understood.

OBJECTIVE

The present study aimed to investigate the role of muscarinic receptor (M receptor) in regulating the immune cell activity in nasal mucosa by using surgical removed nasal mucosa from patients with nasal polyposis (NP) as a study platform.

METHODS

Human nasal mucosal sample was collected from inferior turbinectomy of 86 patients with NP or/and allergic rhinitis. Expression of tumor necrosis factor alpha (TNF-alpha), M receptor, OX40 ligand was measured in nasal mucosa by enzyme-linked immunosorbent assay, flow cytometry, and Western blotting assay.

RESULTS

When compared with non-NP (nNP) nasal mucosa, contents of TNF-alpha and TNF-alpha+ cells markedly increased in NP nasal mucosa; immune staining colocalized M3 receptor+ and TNF-alpha+ cells in NP nasal mucosa; exposure of isolated CD4+ T cells to methacholine induced the release of TNF-alpha. We also found CD11c+/M3 receptor+ cells in NP nasal mucosa. Methacholine increased the expression of OX40L in dendritic cells. Staphylococcal (S) aureus and S. enterotoxin B (SEB) were detected in NP nasal mucosa. Exposure of dendritic cells or naïve CD4+ T cells to SEB initiated the expression of M3 receptor at mRNA and protein levels.

CONCLUSIONS

The present data demonstrate that parasympathetic activity has the capacity to activate dendritic cells to release OX40 ligand, the latter induces CD4+ T cells to produce IL-4 and TNF-alpha that may further contribute to the pathogenesis of NP.

Migration of regulatory T cells toward airway epithelial cells is impaired in chronic rhinosinusitis with nasal polyposis

The pathogenesis of chronic rhinosinusitis with nasal polyposis (CRSwNP) is still unclear. To evaluate the role of regulatory T cells (Treg) in the pathogenesis of nasal polyposis, we tested migration potential of Treg purified from subjects with CRSwNP, CRS without NP and controls. The nasal tissue expressions of FOXP3 were analyzed by means of RT-PCR and double immunohistochemistry. Chemotaxis assays were used to evaluate the migration potential of Treg onto bronchial epithelial cells and primary nasal epithelial cells, and toward chemokines. FOXP3(+)CD3(+) cells frequency and FOXP3 transcript expression in nasal tissue, and migration potentials of Treg toward airway epithelial cells and CCL1 were significantly lower in CRSwNP compared with other groups (P<0.05). These results indicate that migration potential of Treg is decreased in CRSwNP subjects, and this may be one of the reasons why tissue infiltration of Treg was decreased as seen in the immunohistochemistry of nasal polyps from CRSwNP subjects.

Screening for staphylococcal superantigen genes shows no correlation with the presence or the severity of chronic rhinosinusitis and nasal polyposis

BACKGROUND

Staphylococcus aureus secretes numerous exotoxins which may exhibit superantigenic properties. Whereas the virulence of several of them is well documented, their exact biological effects are not fully understood. Exotoxins may influence the immune and inflammatory state of various organs, including the sinonasal mucosa: their possible involvement in chronic rhinosinusitis has been suggested and is one of the main trends in current research. The aim of this study was to investigate whether the presence of any of the 22 currently known staphylococcal exotoxin genes could be correlated with chronic rhinosinusitis.

METHODOLOGY/PRINCIPAL FINDINGS

We conducted a prospective, multi-centred European study, analysing 93 Staphylococcus aureus positive swabs taken from the middle meatus of patients suffering from chronic rhinosinusitis, with or without nasal polyposis, and controls. Strains were systematically tested for the presence of the 22 currently known exotoxin genes and genotyped according to their agr groups. No direct correlation was observed between chronic rhinosinusitis, with or without nasal polyposis, and either agr groups or the presence of the most studied exotoxins genes (egc, sea, seb, pvl, exfoliatins or tsst-1). However, genes for enterotoxins P and Q were frequently observed in nasal polyposis for the first time, but absent in the control group. The number of exotoxin genes detected was not statistically different among the 3 patient groups.

CONCLUSIONS/SIGNIFICANCE

Unlike many previous studies have been suggesting, we did not find any evident correlation between staphylococcal exotoxin genes and the presence or severity of chronic rhinosinusitis with or without nasal polyposis.

CRTH2 mediates the activation of human Th2 cells in response to PGD(2) released from IgE/anti-IgE treated nasal polyp tissue

BACKGROUND

Mast cells release mediators upon stimulation that contribute to the pathogenesis of chronic airway disease, including the recruitment and activation of Th2 lymphocytes. The objective was to determine the involvement of prostaglandin D(2) (PGD(2)) and its receptors in the chemotaxis of Th2 cells, using nasal polyp tissue.

METHODS

Tissue explants from ten patients with nasal polyposis were incubated with RPMI alone or RPMI containing IgE/anti-IgE for 30 min. Some samples were treated with diclofenac to inhibit the production of PGD(2). Supernatants were assayed for PGD(2) content and for their ability to promote human Th2 cell chemotaxis in the presence and absence of a CRTH2 antagonist. Transcript levels of D protanoid receptor type 1 (DP(1)), chemoattractant receptor-homologous receptor expressed on Th2 cells (CRTH2) and PGD(2) synthase were analysed by real time PCR.

RESULTS

Increased release of PGD(2) by nasal polyp tissue treated with IgE/anti-IgE was significantly inhibited by preincubation of the tissue with diclofenac. Transcript levels of PGD(2) synthase, DP(1) and CRTH2 receptors increased after stimulation with IgE/anti-IgE. Supernatants from IgE/anti-IgE-stimulated nasal polyp tissue caused significantly increased chemotaxis of Th2 cells. The levels of PGD(2) produced and the degree of Th2 cell chemotaxis were highly correlated. Diclofenac inhibited the production of Th2 cell chemotactic activity, and the chemotactic effect of the supernatant on Th2 cells was inhibited by the CRTH2 antagonist ramatroban.

CONCLUSION

These data suggest that in immunologically activated nasal polyp tissue, PGD(2) produced by mast cells promotes the migration of Th2 cells through a CRTH2 dependent mechanism.

[On the problem of medicamentous therapy of chronic polypous rhinosinusitis]

Chronic polypous rhinosinusitis (CPS) is currently regarded as a condition requiring medicamentous therapy rather than surgical treatment at the early stages. The choice of therapeutic modalities depends on pathogenetic mechanisms underlying formation of polyps. The International Consensus Conference on Nasal Polyposis (2006) and European documents EAACI - EP3OS (2007) recommend topical (endonasal) glucocorticoids, systemic antibiotics (long-term treatment with low doses of macrolides), antimycotic preparations, and other pharmaceuticals as the main medicinal products for the management of polypous rhinosinusitis (PR). Based on the concept of CPS as an immune-dependent condition, the authors developed the rationale for the use of immunomodulators in combination with etiotropic drugs (antiviral, antibacterial, and antimycotic) for the management of this disease. Advantages of Imunofan application (both local and systemic) during surgical intervention for the treatment of nasal polyps are discussed. It is concluded that combined medicamentous treatment restricts the growth and recurrence of nasal polyps.

Ratio of myeloid and plasmacytoid dendritic cells and TH2 skew in CRS with nasal polyps

BACKGROUND

The role of myeloid and plasmacytoid dendritic cells and its consequences for the T(H)2 skew in chronic rhinosinusitis (CRS) with nasal polyps (CRSNP(+)) should be detailed.

METHODS

In 18 CRS patients without nasal polyps (CRSNP(-)), 35 CRSNP(+) patients and 22 patients with nasal structural abnormalities without rhinosinusitis (controls), dendritic cells (DC) were differentiated into myeloid (mDC) and plasmacytoid (pDC) subtypes using an antibody cocktail including CD1c (BDCA-1) and CD303 (BDCA-2) in peripheral blood mononuclear cells (PBMC) and single cell preparations of sinonasal mucosa by flow cytometry. Moreover, cells were analysed for expression of CD45, CD3, CD4, CXCR3 (T(H)1) and CCR4 (T(H)2) and IFN-gamma, IL-5, TGF-beta1, TGF-beta2, ECP and total IgE in nasal secretions were determined. As a possible confounder, Staphylococcus aureus in nasal lavages was detected.

RESULTS

The tissue mDC/pDC-ratio was 1.7 (1.0-2.4) in controls, 3.0 (1.8-4.0) in CRSNP(-) and 0.8 (0.6-1.0) in CRSNP(+) (P < 0.01). In tissue samples, the T(H)1/T(H)2 ratio was 12.6 (6.4-16.0) in controls, 12.5 (6.9-21.2) in CRSNP(-) and 1.8 (1.3-3.6) in CRSNP(+) (median and interquartile range, P < 0.001). Less pronounced differences were found in PBMC. S. aureus detection rates or TGF-beta levels did not differ between patient groups and S. aureus detection had no influence on the parameters investigated.

CONCLUSION

A significant T(H)2 skew in CRSNP(+) could be confirmed on the cellular level. It was driven by low myeloid dendritic cell numbers. The T(H)2 skew did not correlate with S. aureus detection. The data support the concept that CRSNP(+) and CRSNP(-) are pathophysiologically distinct.

[The relationship between eosinophilia and parameters of systemic and local adaptive immunity in patients with polypous rhinosinusitis]

Results of the study on adaptive immunity in patients with polypous rhinosinusitis (PRS) proved to depend on the degree of eosinophilia in the peripheral blood. The patients were allocated to two groups, one comprised of those having up to 150 eosinophils per 1 microliter the other of the patients with a higher eosinophil concentration. Patients of the former group had a significantly reduced number of CD3+, CD4+, CD8+, and CD20+cells in the peripheral blood that may indicate the necessity of administering immunotropic agents. The opposite picture is characteristic of the latter group in which a rise in the number of the above cells is associated with the increased amount of IgG- and IgA-positive cells. In this situation, the use of systemic immunotropic agents should be restricted. It is concluded that evaluation of systemic and local adaptive immunity is of importance for the choice of an adequate strategy for the treatment of patients with polypous rhinosinusitis.

[The dependence of Toll-receptor expression on pathomorphological features of nasal polyps in patients with polypous rhinosinusitis]

This work was designed to study expression of Toll 1-10 receptors on the surface of cells present in inflammatory infiltrate from nasal polyps and peripheral blood of the patients with polypous rhinosinusitis. It was shown that the intensity of expression depended on the pathomorphological characteristics of nasal polyps. Tissues removed from the patients with polyps of the oedematous type contained more Toll-10 positive cells and showed enhanced expression of Toll-5 receptors on monocytes and lymphocytes, Toll-3 receptors on monocytes, granulocytes, and lymphocytes, and Toll-9 receptors on granulocytes. In contrast, patients with polypous rhinosinusitis and nasal polyps of the fibroedematous type exhibited suppressed expression of Tol-7 receptors on monocytes and Toll-10 receptors on granulocytes coupled to the reduced number of Toll-6 positive lymphocytes as well as enhanced expression of Toll-1 receptors on monocytes, Toll-4 and Toll-5 receptors on granulocytes, and Toll-5 receptors on lymphocytes. It is concluded that only Toll-1, Toll-3, Toll-4, Toll-5, Toll-7, Toll-9 and Toll-10 receptors of their ten types identified thus far in patients with polypous rhinosinusitis and two pathomorphological variants of nasal polyps undergo modulation of expression. These findings open up prospects for the use of new methods for the management of patients with polypous rhinosinusitis by affecting selected components of congenital immunity.

[Pathogenesis and clinical features of polypous rhinosinusitis]

The paper presents recommendations of the current European and Russian documents concerning pathogenesis of polypous rhinosinusitis (International Consensus Conference on Nasal Polyposis (2006), European documents EAACI - EP3OS (2007), and Summit of the Russian Society of Rhinologists "Nasal polyposis and inflammation" (2009)). The bilateral polypous process in the nasal cavity is considered to be a "special form of rhinosinusitis" in which bacterial superantigens or fungal infection induce chronic eosinophilic inflammation. Researchers of the ENT Department, Rostov State Medical University, undertook analysis of the results of long-term comprehensive examination of patients with polypous rhinosinusitis that included clinical, bacteriological, histomorphological, and allergological studies as well as evaluation of local and systemic immunity. The data obtained allowed to describe one of the forms of polypous rhinosinusitis as chronic infection-dependent allergic rhinosinusitis with the manifestation of all four types of allergic reactions, formation of the autoimmune component, and development of persistent immune inflammation leading to remodeling of endonasal mucosa. In all these cases, the process progressed parallel to the development of combined secondary immune deficiency (SID). A hypothetical scheme of pathogenesis of chronic polypous allergic rhinosinusitis is proposed.

Evidence of bacterial biofilms in nasal polyposis

INTRODUCTION

The pathogeny of chronic rhinosinusitis with nasal polyposis (CRS/NP) has not been elucidated. Bacterial exotoxins have been implicated in many inflammatory chronic diseases, such as chronic otitis, chronic tonsillitis, cholesteatomas, and more recently CRS/NP. We propose that the bacteria in CRS/NP are not only present in a planktonic state, but also occur in microbial communities as biofilms.

OBJECTIVE

To determine and characterize the presence of biofilms in CRS/NP.

METHODS

We performed a prospective study in 12 patients undergoing endoscopic sinus surgery for nasal polyposis. Ten patients without CRS/NP who underwent septoplasty were included as a control group. Tissue samples were obtained from the inferior turbinate mucosae. The bacteria were isolated and typified and the material was examined in vitro using a spectrophotometer, and in vivo using optical microscopy and confocal scanning laser microscopy.

RESULTS

Moderate to high in vitro biofilm-forming capacity was detected in 9 out of 12 patients with CRS/NP (mean [SD] optical density values of between 0.284 [0.017] and 3.337 [0.029]). The microorganisms isolated were Staphylococcus (5 patients), Streptococcus viridans, Pseudomonas aeruginosa, Enterococcus faecalis and Streptococcus viridans/Corynebacterium. Biofilms were demonstrated in vivo in 2 patients and no biofilm structures were evident in any of the controls.

CONCLUSION

This study demonstrates the presence of bacterial biofilms in patients with CRS/NP. This chronic inflammatory factor might contribute to nasal mucosa damage, increased inflammatory cells in tissue, and the subsequent hyperplasic process.

[Comparative analysys of immunocorrective effect of ultraviolet irradiation of autoblood and plasmapheresis in patients with recurrent polypous rhinosinusitis]

The objective of the present study was to evaluate the immune status of patients with chronically recurring polypous rhinosinusitis (CRPS) for the identification of the key markers of immune disorders. Assessment of the efficiency of traditional therapy during the postoperative period demonstrated that it was very low in terms of beneficial effect on the major components of the immune system, T and B lymphocytes. Determination of the frequency of immune disorders during irradiation of autoblood with ultraviolet light and plasmapheresis in the postoperative period and evaluation of "true" effects of these treatments revealed their significant quantitative immunostimulating action. Integral evaluation (rank-sum analysis) demonstrated similar therapeutic efficiency of the two methods.

Endothelial L-selectin ligand expression in nasal polyps

BACKGROUND

L-selectins on leukocytes and their counter-receptors on endothelial cells have been shown to be involved in leukocyte recruitment in chronic rhinosinusitis without nasal polyps (NP).

OBJECTIVES

The purpose of this study was to evaluate the expression level of functionally active endothelial L-selectin ligands in NP obtained from patients with NP of different etiology [simple NP, antro-choanal polyps (ACP) and cystic fibrosis (CF) NP] and inferior turbinate specimens of healthy controls and to compare these levels to the presence of various leukocyte subsets.

METHODS

Nasal polyp specimens and healthy nasal mucosa specimens were obtained from patients undergoing surgery and were immunohistochemically stained with monoclonal antibodies detecting CD34, sialyl Lewis x (sLe(x)) of sulfated extended core 1 lactosamines and various leukocyte subsets.

RESULTS

All NP are characterized by a decrease in the number of CD34+ vessels. The number of eosinophils and the percentage of vessels expressing endothelial sulfated sLe(x) epitopes is upregulated in all groups of simple NP. Tissue eosinophilia is increased in those patients with increased disease severity (acetyl salicylic acid intolerance), but the percentage of endothelial sulfated sLe(x) epitopes is not. Results on CF NP are similar to those observed for simple NP. Antro-choanal polyps, on the contrary, are characterized by low numbers of tissue eosinophils and relatively few vessels expressing endothelial sulfated sLe(x) epitopes.

CONCLUSIONS

Our results suggest that functionally active L-selectin ligands might play a role in guiding leukocyte traffic into NP in patients with simple NP and CF NP but not ACP.

Quantitative proteomics of nasal mucus in chronic sinusitis with nasal polyposis

BACKGROUND

Proteomics has been used as a tool for identification of the protein content of nasal mucus in diseased and healthy subjects. Thirty-five proteins in both chronic rhinosinusitis (CRS) and control groups were identified in a previous study by our group using conventional mass spectrometry analysis. Ten of these proteins were related to innate and acquired immunity and showed differences in expression between the two groups.

OBJECTIVE

To investigate the quantitative differential expression of specific nasal mucus proteins previously identified by our group using multiple reaction monitoring (MRM) mass spectrometry in patients with CRS with nasal polyposis compared with normal subjects.

METHODS

In a prospective case control study, nasal mucus from patients and control subjects was collected, desalted, resolubilized, and digested using proteolytic enzymes. Previously identified nasal mucus proteins with differential expression in CRS patients were targeted and quantitatively measured using MRM mass spectrometry.

RESULTS

Analysis of 12 samples (6 patients and 6 controls) identified 7 of the 10 targeted proteins, many of which were related to innate and acquired immunity. Quantitative analysis showed differential expression in CRS patients compared with control subjects. A detailed analysis and characterization of the protein isolates is outlined.

CONCLUSION

This is the first proteomics study of nasal mucus in CRS with polyposis using the MRM technique. The findings suggest that innate and acquired immunity may play a role in the pathophysiology of CRS. Future steps in evaluating the protein characteristics of the mucus of CRS patients are aimed at developing biomarkers and potentially targeted therapies.

Differential expression of the interleukin 5 receptor alpha isoforms in blood and tissue eosinophils of nasal polyp patients

BACKGROUND

Given the key role of interleukin-5 (IL-5) in eosinophil function, we investigated the regulated expression of the membrane-anchored (TM-IL-5Ralpha) isoform, or a secreted (SOL IL-5Ralpha) isoform, on both protein and transcript level in vitro and in vivo.

METHODS

A real-time PCR, FACS and ELISA were established to determine IL-5Ralpha isoform expression in peripheral blood and nasal tissue from control subjects and nasal polyp (NP) patients with or without asthma. Human peripheral blood eosinophils were incubated with IL-5 and were analyzed for SOL-IL-5Ralpha and TM-IL-5Ralpha mRNA and protein levels in comparison with CD-69 expression.

RESULTS

SOL-IL-5Ralpha and TM-IL-5Ralpha mRNA and protein expression was significantly increased in NP vs controls. In polyp tissue, SOL-IL-5Ralpha expression correlated to disease severity and eosinophils counts, whereas TM-IL-5Ralpha levels were inversely correlated to eosinophils counts and SOL-IL-5Ralpha expression. FACS analysis revealed increased CD-69 and decreased TM-IL-5Ralpha expression in NP tissue eosinophils vs blood eosinophils. Incubation of blood eosinophils with IL-5 caused up-regulation of CD-69 and down-regulation of TM-IL-5Ralpha after 2 and 24 h.

CONCLUSION

The expression of SOL-IL-5Ralpha and TM-IL-5Ralpha differs according to the eosinophil activation state and localization in the body (blood vs tissue) and may therefore be involved in the fine-tuning of the eosinophil homeostasis. Exposure of eosinophils to IL-5 reduces their responsiveness to IL-5 by regulated expression of the IL-5Ralpha isoforms. Since, TM-IL-5Ralpha is down-regulated and SOL-IL-5Ralpha (antagonistic) is upregulated in NP tissue, our findings are important to understand the clinical trials with anti-IL-5 in humans.

Important research questions in allergy and related diseases: 3-chronic rhinosinusitis and nasal polyposis - a GALEN study

Chronic rhinosinusitis is one of the most common health care challenges, with significant direct medical costs and severe impact on lower airway disease and general health outcomes. The diagnosis of chronic rhinosinusitis (CRS) currently is based on clinical signs, nasal endoscopy and CT scanning, and therapeutic recommendations are focussing on 2 classes of drugs, corticosteroids and antibiotics. A better understanding of the pathogenesis and the factors amplifying mucosal inflammation therefore seems to be crucial for the development of new diagnostic and therapeutic tools. In an effort to extend knowledge in this area, the WP 2.7.2 of the GA(2)LEN network of excellence currently collects data and samples of 1000 CRS patients and 250 control subjects. The main objective of this project is to characterize patients with upper airway disease on the basis of clinical parameters, infectious agents, inflammatory mechanisms and remodeling processes. This collaborative research will result in better knowledge on patient phenotypes, pathomechanisms, and subtypes in chronic rhinosinusitis. This review summarizes the state of the art on chronic rhinosinusitis and nasal polyposis in different aspects of the disease. It defines potential gaps in the current research, and points to future research perspectives and targets.

[Experimental study on overactivation of lymphocytes and cytokines in immunopathogenesis of nasal polyp]

OBJECTIVE

To investigate the expression of CD4, CD69, CD34, RANTES, IL-5 and IL-8 in nasal polyp tissues, and study their roles in the formation of nasal polyp.

METHOD

The expression of CD4, CD69, CD34, RANTES, IL-5 and IL-8 were detected by immunohistochemical method and image analysis in 34 cases of nasal polyps and 30 cases of nasal concha mucosa (LNT).

RESULT

The positive rate of glandular organ hyperplasia, formation of beaker cell, fiber hyperplasia, interstitial edema and infiltration of lymphocyte and eosinophilic granulocyte in nasal polyps were significantly higher than those in nasal concha mucosa (P<0.01). The cell density (piece/mm2) of CD4+, CD69+, IL-5, IL-8, RANTES in 34 nasal polyps was significantly higher than those in nasal concha mucosa (P<0.05). Marked positive correlations were found between expression of CD4, CD69 and RANTES, IL-5 and IL-8 (P<0.05, P<0.01 and P<0.05), expression of IL-5 and RANTES and infiltration level of eosinophilic granulocyte (P<0.05 and P<0.01), and expression of IL-8 and vaso formation on nasal polyps tissue (P<0.01).

CONCLUSION

T lymphocytes and correlated cytokines participate in the immunopathogenesis of nasal polyps; IL-5 and RANTES can prompt the infiltration, the aggregation and the activation of eosinophilic granulocytes; IL-8 can promote the vaso formation in nasal polyps.

Prostaglandin E(2) suppresses staphylococcal enterotoxin-induced eosinophilia-associated cellular responses dominantly through an E-prostanoid 2-mediated pathway in nasal polyps

BACKGROUND

Recent investigations have revealed that staphylococcal enterotoxins (SEs), COX metabolism, or both might participate in the pathogenesis of eosinophilic airway diseases, such as chronic rhinosinusitis with nasal polyposis.

OBJECTIVE

We sought to determine whether COX metabolism, especially prostaglandin (PG) E(2), plays a significant role in SE-induced cellular responses in nasal polyps.

METHODS

Dispersed nasal polyp cells (DNPCs) were prepared from nasal polyps by means of enzymatic digestion. DNPCs were cultured with SEB in the presence or absence of COX inhibitors (diclofenac and indomethacin) for 72 hours; then the levels of IL-5, IL-13, RANTES, and eotaxin in the supernatants were measured. The effect of PGE(2) on SEB-induced responses by diclofenac-treated DNPCs was examined, especially in terms of receptor specificity.

RESULTS

DNPCs produced significant amounts of IL-5, IL-13, and RANTES in response to SEB. COX inhibitors significantly increased the production of these cytokines. The degree of local eosinophilia was significantly and positively correlated with the changes in IL-5 production induced by diclofenac treatment. PGE(2) significantly and dose-dependently inhibited SEB-induced IL-5, IL-13, and RANTES production by diclofenac-treated DNPCs. E-prostanoid (EP) 2 receptor-selective agonist strongly inhibited the production of all 3 cytokines. EP3 and EP4 receptor-selective agonists partially suppressed these responses, whereas EP1 receptor-selective agonist did not. Interestingly, all of the combined treatments with 2 of the 4 EP receptor-selective agonists significantly inhibited the SEB-induced responses by diclofenac-treated DNPCs.

CONCLUSIONS

These results suggest that PGE(2) inhibits the pathogenesis of SEB-induced eosinophilic inflammation primarily through the EP2-mediated pathway in patients with chronic rhinosinusitis with nasal polyposis.

Activated mammalian target of rapamycin is associated with T regulatory cell insufficiency in nasal polyps

BACKGROUND

Decreased infiltration of Foxp3+ T regulatory cell (Treg) is considered to be critical for the Th1/Th2 dysregulation of nasal polyps, while the cellular mechanism underlying Foxp3+ Treg insufficiency is currently not well defined.

METHODS

We attempted to investigate the tissue expression of phosphorylated mammalian target of rapamycin (pmTOR) and infiltration of Foxp3+ Tregs in 28 nasal polyps and 16 controls by histological staining. We also evaluated the effects of blocking the mTOR signaling pathway with rapamycin on T cell phenotype selection and Foxp3+CD4+ Tregs expansion in a tissue culture system.

RESULTS

Significantly increased infiltration of pmTOR+ inflammatory cells and decreased infiltration of Foxp3+CD4+ Tregs into nasal polyps was observed, with an inverse association. In the tissue culture system, we detected significantly elevated Foxp3 expression and IL-10 production, as well as an increased percentage of Foxp3+ Tregs in nasal polyps after blocking the mTOR signaling pathway with rapamycin.

CONCLUSION

Here we demonstrate for the first time that the mTOR signaling pathway is associated with Foxp3+ Tregs insufficiency in nasal polyps. Inhibition of the mTOR signaling pathway may be helpful for enhancement of Foxp3+ Treg expansion, as well as modulation of T cell phenotype imbalances in nasal polyps.