Polymorphisms in RYBP and AOAH genes are associated with chronic rhinosinusitis in a Chinese population: a replication study

Background

The development of CRS is believed to be the result of combined interactions between the genetic background of the affected subject and environmental factors.

Objectives

To replicate and extend our recent findings from genetic association studies in chronic rhinosinusitis (CRS) performed in a Canadian Caucasian population in a Chinese population.

Methods

In a case-control replication study, DNA samples were obtained from CRS with (n = 306; CRSwNP) and without (n = 332; CRSsNP) nasal polyps, and controls (n = 315) in a Chinese population. A total of forty-nine single nucleotide polymorphisms (SNPs) selected from previous identified SNPs associated with CRS in Canadian population, and SNPs from the CHB HapMap dataset were individually genotyped.

Results

We identified two SNPs respectively in RYBP (rs4532099, p = 2.15E–06, OR = 2.59) and AOAH (rs4504543, p = 0.0001152, OR = 0.58) significantly associated with whole CRS cohort. Subgroup analysis for the presence of nasal polyps (CRSwNP and CRSsNP) displayed significant association in CRSwNP cohorts regarding to one SNP in RYBP (P = 3.24^E–006, OR = 2.76). Evidence of association in the CRSsNP groups in terms of 2 SNPs (AOAH_rs4504543 and RYBP_rs4532099) was detected as well. Stratifying analysis by gender demonstrated that none of the selected SNPs were associated with CRSwNP as well as CRSsNP. Meanwhile 3 SNPs (IL1A_rs17561, P = 0.005778; IL1A_rs1800587, P = 0.009561; IRAK4_rs4251513, P = 0.03837) were associated with serum total IgE level.

Conclusions

These genes are biologically plausible, with roles in regulation of transcription (RYBP) and inflammatory response (AOAH). The present data suggests the potential common genetic basis in the development of CRS in Chinese and Caucasian population.

Memory T cells in the chronic inflammatory microenvironment of nasal polyposis are hyporesponsive to signaling through the T cell receptor

A majority of T cells from chronic inflammatory tissues derived from patients with nasal polyposis were found to express an effector memory phenotype. We report here that these memory T cells failed to activate NF-κB in response to TCR stimulation but responded normally when the proximal TCR signaling molecules were bypassed with PMA and ionomycin. The dysfunction of these cells was associated with a decrease in the phosphorylation of several TCR proximal signaling molecules including ZAP70, Lck and SLP-76. In addition to the disruption in the TCR signaling pathway, the nasal polyp-associated T cells were shown to have a defect in their ability to translocate LAMP-1 to the cell surface. The results presented here establish that the phenotype and anergy of the T cells in the nasal polyp are similar to those which is seen in memory T cells derived from human tumors and other sites of chronic inflammation.

Cytokine profiles in Japanese patients with chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) is classified in CRS without nasal polyp (CRSsNP) and CRS with nasal polyp (CRSwNP) in western countries, whereas this classification was not common so far in Japan. Studying inflammatory mediators in clearly defined disease subgroups may lead to a better differentiation of chronic sinus diseases.

METHODS

Homogenates of sinonasal mucosal tissue from 14 controls, 9 CRSsNP patients, and 19 CRSwNP patients were assayed for transforming growth factor (TGF)-β, interleukin (IL)-5, immunoglobulin E (IgE), Staphylococcus enterotoxin (SAE)-IgE, eosinophil-catioic protein (ECP), myeloperoxidase (MPO), IL-1β, IL-6, and IL-8 by enzyme-linked immunosorbent assay or UNICAP system.

RESULTS

CRSwNP had significantly higher levels of IL-5, IgE, SAE-IgE, and ECP compared with CRSsNP and controls. CRSsNP was characterized by high levels of TGF-β, while CRSwNP showed a Th2 polarization and lower levels of TGF-β. Especially, in CRSwNP samples, 68.4% were eosinophilic (ECP/MPO ratio >1), and 52.6% were SAE-IgE positive. On the other hand, in 9 CRSsNP patients, eosinophilic or SAE-IgE positive sample was only one sample respectively. Additionally, 31.6% of CRSwNP were asthmatic patients, while none of CRSsNP patient was suffering from bronchial asthma.

CONCLUSIONS

This study is thought to be the first one that showed the cytokine profiles in Japanese CRSs/wNP similar to those of European CRS. Based on mediator profiles, we suggest that CRSsNP and CRSwNP are distinct disease entities within the group of chronic sinus diseases.

Effect of [6]-gingerol on myofibroblast differentiation in transforming growth factor beta 1-induced nasal polyp-derived fibroblasts

BACKGROUND

[6]-Gingerol is one of the major pungent principles of ginger and has diverse effects, including anti-inflammatory, and antioxidative effects. Reactive oxygen species (ROS) are released during the phenotypic transformation of fibroblasts to myofibroblasts, a process that is involved in the growth of nasal polyps by inducing extracellular matrix (ECM) accumulation. The purpose of this study was to determine the effect of [6]-gingerol on myofibroblast differentiation and collagen production of nasal polyp-derived fibroblasts (NPDFs) and to determine if the effect of [6]-gingerol is linked to an antioxidant effect.

METHODS

NPDFs were incubated and treated with transforming growth factor (TGF) beta 1. The ROS generated by NPDFs were determined using 2″,7″-dichlorfluorescein-diacetate. The fluorescence was captured by a fluorescent microscope and measured using a fluorometer. The expression of alpha-smooth muscle actin (SMA) and collagen type IV mRNA was determined by a reverse transcription-polymerase chain reaction, and the expression of α-SMA protein and pSmad2/3 was determined by immunofluorescence microscopy and or Western blotting. The amount of total soluble collagen production was analyzed by the SirCol collagen dye-binding assay.

RESULTS

TGF-beta 1 stimulation increased ROS production by NPDFs. [6]-Gingerol decreased the production of ROS in TGF-beta 1-induced NPDFs. Myofibroblast differentiation, collagen production, and phosphorylation of Smad2/3 were prevented by [6]-gingerol and inhibition of ROS generation with antioxidant such as diphenyliodonium, N-acetylcysteine, and ebselen.

CONCLUSION

These results suggest the possibility that [6]-gingerol may play an important role in inhibiting the production of the ECM in the development of nasal polyps through an antioxidant effect.

Expression of nitric oxide synthases in leukocytes in nasal polyps

BACKGROUND

Nitric oxide (NO) has various roles in airway physiology and pathophysiology. Monitoring exhaled NO levels is increasingly common to measure airways inflammation and inhaled NO studied for its therapeutic value in premature infants and adult respiratory distress syndrome. NO is produced by 3 isoforms of NO synthase (NOS1, 2, 3), and each can play distinct and perhaps overlapping roles in the airways. However, the distribution, regulation, and functions of NOS in various cells in the upper airways, particularly in leukocytes, are incompletely understood.

OBJECTIVE

To characterize the expression of NOS isoforms in leukocytes in normal middle turbinate tissues (MT) and in inflammatory nasal tissue (nasal polyps, NP).

METHODS

Normal MT tissue was collected from surgical specimens that were to be discarded. The NP samples were from surgical tissue archives of 15 patients with chronic rhinosinusitis. Isoforms of NOS in cells were identified by double immunostaining using NOS isoform-specific and leukocyte-specific (mast cell, eosinophil, macrophage, neutrophil, or T cell) antibodies.

RESULTS

The proportion of total cells below the epithelium that were positive for each isoform of NOS was higher in NP than in MT. Each isoform of NOS was found in all leukocyte populations studied, and there were significant differences in the percentage of leukocytes expressing NOS isoforms between MT and NP.

CONCLUSION

All isoforms of NOS are expressed in leukocytes in MT and NP, and their expression varies among leukocyte types. Our data provide a basis to investigate the regulation, cell distribution, and distinct functions of NOS isoforms in normal and inflamed nasal tissues.

Influence of allergy on clinical, immunological and histological characteristics of nasal polyposis

OBJECTIVES

Although polyps seem to be a manifestation of the chronic inflammation of nasal/paranasal sinuses mucosa in both allergic and non-allergic subjects, the pathogenesis of nasal polyposis remains unknown. The aim of this prospective study was to compare the clinical characteristics of nasal polyposis in non-allergic and allergic patients, to compare the cytokine levels in nasal secretions in atopic and non-atopic nasal polyp patients and to correlate these levels with eosinophil counts in nasal polyp tissue specimens.

METHODS

This study included thirty patients with nasal polyposis (13 atopic and 17 non-atopic) requiring surgical treatment. Nasal secretion samples were collected from the nasal cavities of all 30 subjects a few days before the surgical treatment. The levels of tumour necrosis factor-alpha (TNF-alpha), tumour necrosis factor-beta (TNF-beta), interleukin (IL)-1beta, IL-2, IL-12, interferon-gamma (IFN-gamma), IL-4, IL-5, IL-6, IL-10, and IL-8 were measured using the flow cytometric method. Each of the 30 patients was staged clinically according to nasal symptom score, endoscopic score and Lund-Mackay computed tomography (CT) score. All these patients had undergone sinus surgery. Eosinophils were counted in hematoxylin- and eosin-stained sections of all nasal polyp samples.

RESULTS

Our results showed that allergy does not modify the symptoms, or the endoscopic and CT findings, of nasal polyposis. We found significantly higher concentrations of IL-4 (p < 0.01), IL-5 (p < 0.05), IL-6 (p < 0.05) and TNF-beta (p < 0.05) in nasal secretions of allergic nasal polyp patients than in non-allergic ones. Eosinophil counts were significantly higher in tissues of atopic patients' polyps than in non-atopic subjects (p < 0.01). No correlation was observed between cytokine levels and eosinophil counts.

CONCLUSION

Non-atopic and atopic patients' polyps have different immunological patterns. Our results showed that the presence of Th2 cytokines was a more significant feature in allergic patients with nasal polyposis than in non-allergic patients.

Differential expression of interleukin-32 in chronic rhinosinusitis with and without nasal polyps

BACKGROUND

  Chronic rhinosinusitis (CRS) is a heterogeneous disease characterized by local inflammation of the upper airways and sinuses and is frequently divided into polypoid CRS (CRSwNP) and nonpolypoid CRS (CRSsNP). However, the mechanism of inflammation in CRS has still not been fully elucidated. The aim of the study was to investigate the role of interleukin-32 (IL-32), a recently discovered proinflammatory cytokine, in CRS.

METHODS

  We collected nasal epithelial cells and nasal tissue from patients with CRS and control subjects. We assayed mRNA for IL-32 by real-time PCR and measured IL-32 protein using ELISA, Western blot, and immunohistochemistry.

RESULTS

  The expression of mRNA for IL-32 was elevated in epithelial cells from uncinate tissue from patients with CRSsNP compared with patients with CRSwNP (P < 0.05), control subjects (P=0.06), and epithelial cells from nasal polyp (NP) tissue (P < 0.05). Production of IL-32 was induced by IFN-γ, TNF, and dsRNA in primary airway epithelial cells. In whole-tissue extracts, the expression of IL-32 protein was significantly elevated in patients with CRSwNP compared with patients with CRSsNP and control subjects. Immunohistochemistry data showed that IL-32 was detected in mucosal epithelial cells and inflammatory cells in the lamina propria. Levels of IL-32 were correlated with the levels of CD3 and macrophage mannose receptor in NP tissue. Immunofluorescence data showed IL-32 co-localization with CD3-positive T cells and CD68-positive macrophages in NPs.

CONCLUSION

  Overproduction of IL-32 may be involved in the pathogenesis of CRS, although the role of IL-32 in the inflammation in CRSsNP and CRSwNP may be different.

Association between the functional polymorphism C-159T in the CD14 promoter gene and nasal polyposis: potential role in asthma

BACKGROUND

Nasal polyposis (NP) is a chronic inflammatory disease that is frequently associated with allergy and asthma. Corticosteroid therapy and surgical removal of polyps are the 2 most common treatment strategies for NP. Various allergic and inflammatory mediators are thought to play a major role in the pathophysiology of this disorder. The CD14 gene is located on chromosome 5q31-32, which is considered a critical region for several allergic and atopic diseases, including asthma. Consequently, variations in CD14 could have functional effects on the etiology and severity of allergy and asthma. The aim of this study was to investigate the association between the polymorphism C-159T in the CD14 gene of patients with NP and controls.

METHODS

The study population comprised 106 patients with NP diagnosed based on computed tomography scan of the paranasal sinus, endoscopy, and histological examination. Findings were compared with those from 87 controls. The frequency of C-159T was determined using polymerase chain reaction-restriction fragment length polymorphism analysis. DNA was extracted using the salting out technique.

RESULTS

A significant association was observed between C-159T and NP (P = .04). Patients with the CC genotype at position -159 of the CD14 promoter region had an increased risk of asthma (OR, 3.83, 95% CI, 0.99-13.91; P < .02). However, we did not find an association between the distribution of C-159T and serum immunoglobulin E level.

CONCLUSIONS

A genetic variation in the CD14 promoter might play a role in the pathogenesis of NP and in the incidence of asthma.

[Imbalance of Th17/Treg cell ratio in peripheral blood of patients with nasal polyposis and its clinical significance]

AIM

To observe the distribution of Th17 cells and Foxp3(+);CD4(+);CD25(+); regulatory T cells in peripheral blood of patients with nasal polyposis(NP) and their correlation with clinical patients' condition, and to explore the role of Th17/Treg cell ratio imbalance in pathogenesis of nasal polyposis and significance.

METHODS

The frequencies of Th17 cells and Treg cells were determined in 46 patients with NP and 10 controls by flow cytometry. The 46 patients were divided into two groups according to endoscopy score and CT score: the 1 group (endoscopy score: 2-8 scores; CT score: 3-10 scores, n=23) and the 2 group (endoscopy score: 8-12 scores; CT score: 10-19 scores, n=23).

RESULTS

Th17 cells were significantly higher in the blood of patients with NP compared with the control group (P<0.01), and the percentage was higher in the 2 group than the 1 group (P<0.05). The frequency of Treg cells was significantly decreased in patients with NP compared to the control group (P<0.01), whereas the difference between two groups was not significant. The ratio of Th17/Treg cells was highest in the 2 group (P<0.01), lower in the 1 group (P<0.01) and lowest in control subjects, and the differences were also significant between two groups (P<0.05). Furthermore, it was confirmed that the ratio of Th17/Treg positively correlated with endoscopy score and CT score (P<0.01).

CONCLUSION

The imbalance of Th17/Treg cell ratio characterized by increased Th17 cells and decreased Treg cells exists in peripheral blood of NP patients and may play an important role in the onset and development of NP. The degree of Th17/Treg cell imbalance may associate with clinical presentation.

Retinoic acid-inducible gene 1-like receptors in the upper respiratory tract

BACKGROUND

Retinoic acid-inducible gene 1-like receptors (RLRs) are a novel family of pattern recognition receptors that include retinoic acid-inducible gene 1 (RIG-1), melanoma differentiation-associated gene 5 (MDA-5), and laboratory of genomics and physiology 2 (LGP-2). The knowledge of RLRs and their function in the human airway is limited. This study explores the role of RLRs in the upper respiratory tract.

METHODS

Tonsils, adenoids, nasal polyps, and biopsy specimens from the nasal mucosa were examined for the occurrence of the RIG-1, MDA-5, and LGP-2 using real-time reverse-transcription polymerase chain reaction and immunohistochemistry. The nasopharyngeal epithelial cell line FaDu was cultured with the RIG-1/MDA-5 ligand poly(I:C)/LyoVec (Invivogen, San Diego, CA) and analyzed for cytokine release using ELISA.

RESULTS

RIG-1, MDA-5, and LGP-2 mRNA were found in all tissues tested. The airway epithelium appeared to be their most prominent location. The RIG-1 and MDA-5 mRNA levels were higher in nasal polyps than in normal nasal mucosa, a state that seemed to be reversed by local steroid treatment. Culture of FaDu with poly(I:C)/LyoVec resulted in IL-6 and IL-8 release. No alteration in RLR expression in tonsils was seen on infection.

CONCLUSION

This study shows the presence and functional activity of RLRs in the human upper airways. It also suggests a role for RLRs in nasal polyposis.

[The expression and significance of IGF-1R in nasal polyp and its relationship with allergic rhinitis]

OBJECTIVE

To study the expression of insulin-like growth factor-1 receptor(IGF-1R) in nasal polyps and its relationship with allergic rhinitis.

METHOD

The mRNA and protein expression of IGF-1R in 40 cases (20 cases with allergic rhinitis and 20 cases without) nasal polyps tissue (the CRSWNP group) and 20 middle turbinate tissue samples (the control group) were examined by fluorescence quantitative polymerase chain reaction (FQ-PCR) and immunohistochemistry.

RESULT

The positive staining rate of IGF-1R protein of nasal polyps tissue is 70.8% and that of control is 12.3%, the expression of IGF-1R mRNA of nasal polyp is 0.748 +/- 0.111,which is significant higher than that of the control group is 0.107 +/- 0.208 (P < 0.01). No significant difference of the expression of IGF-1R mRNA between with and without allergic rhinitis cases and between with and without endoscopy sinus surgery history cases in the CRSWNP group.

CONCLUSION

The overexpression of IGF-1R maybe play important roles in the formation of nasal polyp. Hypersensitivity reaction type I mediated by IgE has no contribution to the overexpression of the IGF-1R.

The association between bacterial colonization and inflammatory pattern in Chinese chronic rhinosinusitis patients with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) can be subdivided according to the mucosal inflammatory patterns. In mainland China, apart from interleukin (IL)-5-positive and IL-17-positive polyps, a large group of patients with IL-5/IL-17/interferon-gamma (IFNγ)-negative nasal polyps (referred to as key cytokine-negative (KCN) polyps) can be found.

OBJECTIVE

To further study the KCN polyps and evaluate the associations between bacterial colonization and mucosal inflammatory pattern in KCN vs IL-5-positive nasal polyps.

METHODS

Nasal polyp or nasal turbinate tissue was obtained from 89 Chinese CRSwNP patients and 36 nonatopic control subjects during surgery. Samples without and after SEB exposure were processed for the assessment of pro-inflammatory cytokines and mediators by immunoassay. Prior to surgery, nasal swabs were taken from each patient for microbiological evaluation.

RESULTS

Overall, 80% polyp tissue did not express IL-5, with about 70% (49/71) of these being KCN. Key cytokine-negative nasal polyps were characterized by the synthesis of mediators promoting neutrophilic inflammation (myeloperoxidase (MPO), IL-1β, IL-6 and IL-8), whereas IL-5-positive nasal polyps were characterized by the synthesis of mediators promoting eosinophilic inflammation (IL-5, ECP, total IgE and SE-IgE). Key cytokine-negative nasal polyps were associated with greater Gram-negative bacterial load compared with controls, while IL-5-positive nasal polyps were associated with greater Gram-positive bacterial colonization vs controls and KCN polyps.

CONCLUSION

Our findings suggest that the bacteria colonizing nasal polyps of CRSwNP patients may impact on or be determined by the presence/absence of IL-5.

Alternatively activated macrophages and impaired phagocytosis of S. aureus in chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by biased Th2 inflammation and CRS without nasal polyps (CRSsNP) by a Th1 immune response. Colonization by Staphylococcus aureus is increased in CRSwNP. We aimed to determine macrophage phenotypes in nasal mucosa of CRSwNP and CRSsNP and to examine phagocytosis of S. aureus in these pathologies.

METHODS

Macrophage phenotyping was performed by immunohistochemical staining on nasal mucosa sections from 28 patients; in addition flow cytometry analysis was performed. Tissue homogenate protein levels of IFN-γ, IL-5, IL-6, IL-1β, TGF-β, eosinophil cationic protein (ECP) and total IgE were analyzed and correlated with macrophage subtypes. Phagocytosis of S. aureus was analyzed by flow cytometry. Survival of S. aureus in Thp1 cells in the presence of polarizing cytokines was studied in vitro.

RESULTS

  By immunohistochemical analysis more M2 macrophages were present in CRSwNP than in CRSsNP. This also was positively correlated with increased levels of IL-5, ECP and locally produced IgE and decreased levels of IL-6, IL-1β and IFN-γ. FACS analysis of dissociated nasal tissue confirmed the presence of increased numbers of M2 macrophages (CD206(+) HLADR(+) CD14(+) CD11c(+) CD20(-) ) in CRSwNP as compared to controls, while the number of M1 macrophages (CD206(-) HLADR(+) CD14(+) CD11c(int) CD16(-) CD20(-) ) was not different. Phagocytosis of S. aureus by human tissue derived macrophages was reduced in CRSwNP as compared to macrophages from the control inferior turbinates.

CONCLUSIONS

  Decreased phagocytosis of S. aureus and an M2 activation phenotype in CRSwNP could potentially contribute to persistence of chronic inflammation in CRSwNP.

Lack of association between aspirin-triggered 15-hydroxyeicosatetraenoic acid release and mast cell/eosinophil activation in nasal polyps from aspirin-sensitive patients

BACKGROUND

The mechanism of aspirin sensitivity in patients with asthma and rhinosinusitis has been attributed to arachidonic acid metabolism abnormalities.

OBJECTIVE

We aimed to test whether aspirin-triggered generation of 15-hydroxyeicosatetraenoic acid (15-HETE) in nasal polyp dispersed cells (NPDCs) from aspirin-sensitive patients is associated with activation of inflammatory cells.

METHODS

Polyps were obtained from 11 aspirin-sensitive and 19 aspirin-tolerant patients with chronic rhinosinusitis. NPDCs were stimulated by aspirin or calcium ionophore. Levels of 15-HETE, leukotriene (LT) C4, eosinophil cationic protein (ECP), and tryptase were measured in NPDC supernatant.

RESULTS

NPDCs from aspirin-sensitive patients contained more eosinophils (14% vs 9%, P < .05) and released 2.4-fold more ECP (P < .01) at baseline. Stimulation with aspirin (200 microM) resulted in a significant increase in 15-HETE generation only in tissue from aspirin-sensitive patients (mean increase, 82%) but did not induce any increase in the release of LTC4, ECP, or tryptase. Preincubation with calcium ionophore resulted in significantly enhanced generation of 15-HETE, ECP, tryptase, and LTC4 in patients from both groups. Incubation of NPDCs with misoprostol inhibited aspirin-induced 15-HETE generation in aspirin-sensitive patients and calcium ionophore-induced 15-HETE, ECP, and tryptase release in both aspirin-sensitive and aspirin-tolerant patients.

CONCLUSION

Our study demonstrated that aspirin-induced 15-HETE generation in nasal polyps from aspirin-sensitive patients is not associated with activation of mast cells and eosinophils. Misoprostol has a potent inhibitory effect on the activation of cells derived from the site of nasal mucosal inflammation, regardless of sensitivity to aspirin.

Mucosal tissue polyclonal IgE is functional in response to allergen and SEB

BACKGROUND

Staphylococcus aureus may modify airway disease by inducing local formation of polyclonal IgE antibodies (abs), the role of which is unknown.

METHODS

Nasal mucosal tissue and serum was obtained from 12 allergic rhinitis (AR) and 14 nasal polyp (NP) subjects. Skin prick tests were performed, and total and specific IgE abs to inhalant allergens and enterotoxin B were determined in serum and tissue. Tissue fragments were stimulated with anti-IgE, enterotoxin B, or grass and house dust mite allergens in different concentrations for 30 min. RBL SX38 cells were sensitized with NP homogenates containing IgE and stimulated with grass pollen extracts.

RESULTS

In AR patients, degranulation of tissue mast cells upon allergen exposure and presence of specific IgE to inhalant allergens corresponded in almost all cases. Total IgE concentrations in serum and mucosal tissue homogenates highly correlated. In contrast, in NP patients, reactivity of tissue mast cells upon allergen exposure and presence of specific IgE to inhalant allergens or Staphylococcus aureus enterotoxin B corresponded for tissue, but not for serum. Total IgE was significantly higher in tissue compared to serum and failed to show correlation. Tissue IgE to grass pollen was functional to degranulate RBL cells.

CONCLUSION

We here demonstrate that mucosal IgE abs in NP tissue are functional and able to activate mast cells; specific IgE abs in NP tissue can be found independently of their presence in serum. We postulate that superantigen-induced polyclonal IgE in airway disease contributes to chronic inflammation by continuously activating mast cells.

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.