Increased communication among nasal epithelial cells in air-liquid interface culture

Comprehensive evaluation of type 2 endotype and clinical features in patients with chronic rhinosinusitis with nasal polyps in Taiwan: a cross-sectional study

PURPOSE

Endotype-driven treatment has been introduced in the management of chronic rhinosinusitis with nasal polyps (CRSwNP), and an understanding of the associations between phenotypes and endotypes of CRSwNP will be beneficial in identifying responders. We aimed to determine the correlations between clinical manifestations and type 2 inflammatory mediators of sinonasal tissues.

METHODS

Adult patients undergoing endoscopic sinus surgery for bilateral CRSwNP were prospectively enrolled. Tissue eosinophilia and type 2 mediator expression in tissue homogenates were assessed and correlated with clinical features, including symptoms, comorbidities, blood eosinophil counts, specific allergen immunoglobulin (IgE) testing, computed tomography (CT) scan findings, and Sino-Nasal Outcome Test-22 scores.

RESULTS

A total of 93 subjects were recruited in our study. Fifty-nine (63.4%) cases were identified as the eosinophilic endotype, demonstrating with higher rates of comorbidity of asthma, blood eosinophilia and a high ethmoid-maxillary ratio on CT images. To correlate of phenotypes with the inflammatory mediator profile, multivariate analyses revealed the associations of IgE expression in nasal polyp tissues with allergen sensitization (p = 0.042), CT ethmoid-maxillary ratio (p = 0.001) and tissue eosinophil counts (p = 0.022); the association of interleukin (IL-5) expression with the blood eosinophil percentage (p = 0.020); and the association of IL-13 expression with white blood cell count (p = 0.002) and central compartment-type inflammation (p < 0.001).

CONCLUSION

We demonstrated associations of IgE and IL-5 expression with clinical features of eosinophilic-type inflammation and a significantly elevated level of IL-13 in patients with central-compartment-type CRSwNP. These observations may be useful when considering the use of type 2 biologic treatment and require further validation studies.

The Path from Nasal Tissue to Nasal Mucosa on Chip: Part 1-Establishing a Nasal In Vitro Model for Drug Delivery Testing Based on a Novel Cell Line

In recent years, there has been a significant increase in the registration of drugs for nasal application with systemic effects. Previous preclinical in vitro test systems for transmucosal drug absorption studies have mostly been based on primary cells or on tumor cell lines such as RPMI 2650, but both approaches have disadvantages. Therefore, the aim of this study was to establish and characterize a novel immortalized nasal epithelial cell line as the basis for an improved 3D cell culture model of the nasal mucosa. First, porcine primary cells were isolated and transfected. The P1 cell line obtained from this process was characterized in terms of its expression of tissue-specific properties, namely, mucus expression, cilia formation, and epithelial barrier formation. Using air-liquid interface cultivation, it was possible to achieve both high mucus formation and the development of functional cilia. Epithelial integrity was expressed as both transepithelial electrical resistance and mucosal permeability, which was determined for sodium fluorescein, rhodamine B, and FITC-dextran 4000. We noted a high comparability of the novel cell culture model with native excised nasal mucosa in terms of these measures. Thus, this novel cell line seems to offer a promising approach for developing 3D nasal mucosa tissues that exhibit favorable characteristics to be used as an in vitro system for testing drug delivery systems.

Preliminary Study on the Development of In Vitro Human Respiratory Epithelium Using Collagen Type I Scaffold as a Potential Model for Future Tracheal Tissue Engineering

Pathological conditions of the tracheal epithelium, such as postoperative injuries and chronic conditions, often compromise the functionality of the respiratory epithelium. Although replacement of the respiratory epithelium using various types of tracheal transplantation has been attempted, there is no predictable and dependable replacement method that holds for safe and practicable long-term use. Therefore, we used a tissue engineering approach for ex vivo regeneration of the respiratory epithelium (RE) construct. Collagen type I was isolated from sheep tendon and it was fabricated in a three-dimensional (3D) scaffold format. Isolated human respiratory epithelial cells (RECs) and fibroblasts from nasal turbinate were co-cultured on the 3D scaffold for 48 h, and epithelium maturation was allowed for another 14 days in an air–liquid interface culture system. The scanning electron microscope results revealed a fabricated porous-structure 3D collagen scaffold. The scaffold was found to be biocompatible with RECs and fibroblasts and allows cells attachment, proliferation, and migration. Immunohistochemical analysis showed that the seeded RECs and fibroblasts were positive for expression of cytokeratin 14 and collagen type I markers, respectively, indicating that the scaffold supports the native phenotype of seeded cells over a period of 14 days. Although a longer maturation period is needed for ciliogenesis to occur in RECs, the findings suggest that the tissue-engineered RE construct is a potential candidate for direct use in tracheal epithelium replacement or tracheal tube reengineering.

Clinical characteristics and cytokine profiles of central-compartment-type chronic rhinosinusitis

BACKGROUND

The clinical characteristics of central-compartment-type chronic rhinosinusitis (CRS) in East Asian individuals are not clear. We sought to investigate the clinical features and the cytokine profiles of central-compartment-type CRS in our patient group.

METHODS

Adult patients diagnosed with bilateral CRS were recruited, and patients who had previously undergone sinus surgery and pansinusitis (Lund-Mackay scores >23) were excluded. Central-compartment-type CRS was defined by both endoscopic and radiological features. The symptoms, inhalant allergen sensitization status, endoscopic findings, and radiological assessments were recorded and compared between patients with central-compartment-type CRS and other types of CRS. We also examined the extent of tissue eosinophilia and specific cytokine protein levels (eosinophil cationic protein [ECP], myeloperoxidase [MPO], immunoglobulin E [IgE], interleukin [IL]-4, IL-5, and IL-13) in the sinonasal tissues.

RESULTS

Central-compartment-type CRS was found in 16 (23.9%) patients, and non-central-compartment-type CRS was found in 51 (76.1%) patients. Hyposmia or anosmia as the major symptom was more common in the central-compartment-type CRS group. The numbers of eosinophils in tissue and serum were significantly higher in the central-compartment-type CRS patients. The presence of allergen sensitization was not significantly different between groups. The levels of IL-5 and IL-13 were increased in middle turbinate tissues of patients with central-compartment-type CRS.

CONCLUSION

Central-compartment-type CRS was associated with hyposmia or anosmia, eosinophilic subtypes, and elevated levels of IL-5 and IL-13 in middle turbinate tissues but not necessarily correlated with allergic disease in our patients.

Influenza A virus infection induces indoleamine 2,3-dioxygenase (IDO) expression and modulates subsequent inflammatory mediators in nasal epithelial cells

Background: Nasal epithelial cells are the first site of encounter of the influenza virus, and their innate immune response might define subsequent inflammatory direction.Aims/objectives: We used metabolomics analysis to identify metabolic changes and the regulation of inflammatory cytokines in nasal epithelial cells upon influenza virus infection.Material and methods: We cultured nasal epithelial cells using air-liquid interface (ALI) model. Influenza virus (PR8) infection followed by metabolomic analysis was performed. Furthermore, cytokine expression was analyzed by cytokine array and RT-qPCR.Results: Metabolomic analysis revealed depletion of the tryptophan and accumulation of its metabolite, kynurenine, within 48 h. The major enzyme involved in the tryptophan metabolic pathway, indoleamine 2,3-dioxygenase (IDO), was overexpressed after infection. Cytokine expression array after infection showed increased levels of IL-1α, CCL2, IL-6, CXCL10, CCL5, and CXCL11, and after using 1-methyltryptophan (1-MT) as inhibitor, the expression levels of IL-6 and G-CSF were reduced.Conclusions and significance: Viral infection results in depletion of tryptophan and accumulation of kynurenine via increased cellular IDO activity. Inhibition of IDO activity or replenishment of tryptophan by local application may be a good therapeutic strategy for limiting the initial damage caused by influenza virus in nasal epithelial cells.

The IFN-γ-p38, ERK kinase axis exacerbates neutrophilic chronic rhinosinusitis by inducing the epithelial-to-mesenchymal transition

Chronic rhinosinusitis (CRS) is a heterogeneous and multifactorial inflammatory disease characterized by involvement of diverse types of inflammatory cells. Asian CRS patients frequently show infiltration of neutrophils and an elevated level of interferon (IFN)-γ; by contrast, western patients exhibit eosinophil infiltration and enhanced levels of Th2-related cytokines. Neutrophilia in tissues decreases sensitivity to corticosteroids, but the mechanisms underlying the progression of neutrophilic CRS are unclear. In this study, we investigated the role of IFN-γ in CRS patients with marked neutrophil infiltration. We report that the IFN-γ level is upregulated in the tissues of these patients, particularly those with non-eosinophilic nasal polyps. The level of IFN-γ was significantly correlated with markers of the epithelial-to-mesenchymal transition (EMT). We further demonstrated that IFN-γ induced the EMT via the p38 and extracellular signal-regulated kinase (ERK) pathways in a manner distinct from the hypoxia-inducible factor (HIF)-1α, SMAD, and NF-κB signaling pathways. In a murine nasal polyp (NP) model, blocking the p38 and ERK signaling pathways prevented NP formation and chemotactic cytokine secretion by neutrophils but not eosinophils. Taken together, our results suggest that IFN-γ can induce the EMT in nasal epithelial cells, and thus blocking the p38 and ERK pathways could be an effective therapeutic strategy against neutrophil-dominant CRS.

Isolation and Culture of Primary Mouse Middle Ear Epithelial Cells

Epithelial abnormalities underpin the development of the middle ear disease, otitis media (OM). Until now, a well-characterized in vitro model of the middle ear (ME) epithelium that replicates the complex cellular composition of the middle ear has not been available. This chapter describes the development of a novel in vitro model of mouse middle ear epithelial cells (mMECs), cultured at the air-liquid interface (ALI). This system enables recapitulation of the characteristics of the native murine ME epithelium. We demonstrate that mMECs undergo differentiation into the varied cell populations seen within the native middle ear. Overall, our mMEC culture system can help better understand the cell biology of the middle ear and improve our understanding of the pathophysiology of OM. The model also has the potential to serve as a platform for validation of treatments designed to reverse aspects of epithelial remodeling underpinning OM development.

miR-155 Modulates Cockroach Allergen- and Oxidative Stress-Induced Cyclooxygenase-2 in Asthma

Exposure to cockroach allergen is a strong risk factor for developing asthma. Asthma has been associated with allergen-induced airway epithelial damage and heightened oxidant stress. In this study, we investigated cockroach allergen-induced oxidative stress in airway epithelium and its underlying mechanisms. We found that cockroach extract (CRE) could induce reactive oxygen species (ROS) production, particularly mitochondrial-derived ROS, in human bronchial epithelial cells. We then used the RT² Profiler PCR array and identified that cyclooxygenase-2 (COX-2) was the most significantly upregulated gene related to CRE-induced oxidative stress. miR-155, predicted to target COX-2, was increased in CRE-treated human bronchial epithelial cells, and was showed to regulate COX-2 expression. Moreover, miR-155 can bind COX-2, induce COX-2 reporter activity, and maintain mRNA stability. Furthermore, CRE-treated miR-155^-/- mice showed reduced levels of ROS and COX-2 expression in lung tissues and PGE₂ in bronchoalveolar lavage fluid compared with wild-type mice. These miR-155^-/- mice also showed reduced lung inflammation and Th2/Th17 cytokines. In contrast, when miR-155^-/- mice were transfected with adeno-associated virus carrying miR-155, the phenotypic changes in CRE-treated miR-155^-/- mice were remarkably reversed, including ROS, COX-2 expression, lung inflammation, and Th2/Th17 cytokines. Importantly, plasma miR-155 levels were elevated in severe asthmatics when compared with nonasthmatics or mild-to-moderate asthmatics. These increased plasma miR-155 levels were also observed in asthmatics with cockroach allergy compared with those without cockroach allergy. Collectively, these findings suggest that COX-2 is a major gene related to cockroach allergen-induced oxidative stress and highlight a novel role of miR-155 in regulating the ROS-COX-2 axis in asthma.

From Single Cells to Engineered and Explanted Tissues: New Perspectives in Bacterial Infection Biology

Cell culture techniques are essential for studying host-pathogen interactions. In addition to the broad range of single cell type-based two-dimensional cell culture models, an enormous amount of coculture systems, combining two or more different cell types, has been developed. These systems enable microscopic visualization and molecular analyses of bacterial adherence and internalization mechanisms and also provide a suitable setup for various biochemical, immunological, and pharmacological applications. The implementation of natural or synthetical scaffolds elevated the model complexity to the level of three-dimensional cell culture. Additionally, several transwell-based cell culture techniques are applied to study bacterial interaction with physiological tissue barriers. For keeping highly differentiated phenotype of eukaryotic cells in ex vivo culture conditions, different kinds of microgravity-simulating rotary-wall vessel systems are employed. Furthermore, the implementation of microfluidic pumps enables constant nutrient and gas exchange during cell cultivation and allows the investigation of long-term infection processes. The highest level of cell culture complexity is reached by engineered and explanted tissues which currently pave the way for a more comprehensive view on microbial pathogenicity mechanisms.

Functional effects of TGF-β1 on mesenchymal stem cell mobilization in cockroach allergen-induced asthma

Mesenchymal stem cells (MSCs) have been suggested to participate in immune regulation and airway repair/remodeling. TGF-β1 is critical in the recruitment of stem/progenitor cells for tissue repair, remodeling, and cell differentiation. In this study, we sought to investigate the role of TGF-β1 in MSC migration in allergic asthma. We examined nestin expression (a marker for MSCs) and TGF-β1 signaling activation in airways in cockroach allergen extract (CRE)-induced mouse models. Compared with control mice, there were increased nestin(+) cells in airways and higher levels of active TGF-β1 in serum and p-Smad2/3 expression in lungs of CRE-treated mice. Increased activation of TGF-β1 signaling was also found in CRE-treated MSCs. We then assessed MSC migration induced by conditioned medium from CRE-challenged human epithelium in air/liquid interface culture in Transwell assays. MSC migration was stimulated by epithelial-conditioned medium, but was significantly inhibited by either TGF-β1-neutralizing Ab or TβR1 inhibitor. Intriguingly, increased migration of MSCs from blood and bone marrow to the airway was also observed after systemic injection of GFP(+) MSCs and from bone marrow of Nes-GFP mice following CRE challenge. Furthermore, TGF-β1-neutralizing Ab inhibited the CRE-induced MSC recruitment, but promoted airway inflammation. Finally, we investigated the role of MSCs in modulating CRE-induced T cell response and found that MSCs significantly inhibited CRE-induced inflammatory cytokine secretion (IL-4, IL-13, IL-17, and IFN-γ) by CD4(+) T cells. These results suggest that TGF-β1 may be a key promigratory factor in recruiting MSCs to the airways in mouse models of asthma.

Connexin 32 and 43 mutations: do they play a role in chronic rhinosinusitis?

OBJECTIVE

Dysfunction of the sinonasal epithelium may contribute to the pathogenesis of chronic rhinosinusitis (CRS) including recurrent acute rhinosinusitis (RARS). Mutations in connexin 32 and 43 proteins have been associated with a number of human diseases. The objective of this study is to investigate the role of mutations in connexin 32 or connexin 43 genes in CRS and RARS.

METHODS

Prospective case series of 19 patients with CRS and /or RARS. Clinical and demographic factors were noted and buccal swabs were collected for DNA sequencing of connexin 32 and connexin 43 genes.

RESULTS

One patient was found to have a conservative V193I mutation in the connexin 32 gene. Connexin 43 mutations were found in two patients - a silent R239R mutation and an AAA insertion after the stop codon in the 3' UTR. None of these mutations are associated with any known diseases or predicted to lead to protein dysfunction.

CONCLUSION

Mutations in connexin 32 or 43 genes in patients with CRS, including RARS, appear to be rare. The etiologic role of connexin mutations in chromic rhinosinusitis is suspect, and routine sequencing for connexin mutations in patients with RARS or CRS is not cost effective.

Activated human nasal epithelial cells modulate specific antibody response against bacterial or viral antigens

Nasal mucosa is an immune responsive organ evidenced by eliciting both specific local secretory IgA and systemic IgG antibody responses with intra-nasal administration of antigens. Nevertheless, the role of nasal epithelial cells in modulating such responses is unclear. Human nasal epithelial cells (hNECs) obtained from sinus mucosa of patients with chronic rhinosinusitis were cultured in vitro and firstly were stimulated by Lactococcus lactis bacterium-like particles (BLPs) in order to examine their role on antibody production. Secondly, both antigens of immunodominant protein IDG60 from oral Streptococcus mutans and hemagglutinin (HA) from influenza virus were tested to evaluate the specific antibody response. Stimulated hNECs by BLPs exhibited a significant increase in the production of interleukin-6 (IL-6), and thymic stromal lymphopoietin (TSLP). Conditioned medium of stimulated hNECs has effects on enhancing the proliferation of CD4+ T cells together with interferon-γ and IL-5 production, increasing the costimulatory molecules on dendritic cells and augmenting the production of IDG60 specific IgA, HA specific IgG, IgA by human peripheral blood lymphocytes. Such production of antigen specific IgG and IgA is significantly counteracted in the presence of IL-6 and TSLP neutralizing antibodies. In conclusion, properly stimulated hNECs may impart immuno-modulatory effects on the antigen-specific antibody response at least through the production of IL-6 and TSLP.

Explant culture of gastrointestinal tissue: a review of methods and applications

The gastrointestinal (GI) tract is an important target organ for the toxicity of xenobiotics. The toxic effects of xenobiotics on this complex, heterogeneous structure have been difficult to model in vitro and have traditionally been assessed in vivo. The explant culture of GI tissue offers an alternative approach. Historically, the organotypic culture of the GI tract proved far more challenging than the culture of other tissues, and it was not until the late 1960s that Browning and Trier described the means by which intestinal tissues could be successfully cultured. This breakthrough provided a tool researchers could utilise, and adapt, to investigate topics such as the pathogenesis of inflammatory intestinal diseases, the effect of growth factors and cytokines on intestinal proliferation and differentiation, and the testing of novel xenobiotics for efficacy and safety. This review considers that intestinal explant culture shows much potential for the application of a relatively under-used procedure in future biomedical research. Furthermore, there appear to be many instances where the technique may provide experimental solutions where both cell culture and in vivo models have been unable to deliver conclusive and convincing findings.

Cytotoxic, genotoxic and pro-inflammatory effects of zinc oxide nanoparticles in human nasal mucosa cells in vitro

Despite increasing application of zinc oxide nanoparticles (ZnO-NPs) for industrial purposes, data about potential toxic properties is contradictory. The current study focused on the cyto- and genotoxicity of ZnO-NPs in comparison to ZnO powder in primary human nasal mucosa cells cultured in the air-liquid interface. Additionally, IL-8 secretion as a marker for pro-inflammatory effects was measured. Particle morphology and intracellular distribution were evaluated by transmission electron microscopy (TEM). ZnO-NPs were transferred into the cytoplasm in 10% of the cells, whereas an intranuclear distribution could only be observed in 1.5%. While no cyto- or genotoxicity could be seen for ZnO powder in the dimethylthiazolyl-diphenyl-tetrazolium-bromide (MTT) test, the trypan blue exclusion test, and the single-cell microgel electrophoresis (comet) assay, cytotoxic effects were shown at a ZnO-NP concentration of 50 μg/ml (P<0.01). A significant enhancement in DNA damage was observed starting from ZnO-NP concentrations of 10 μg/ml (P<0.05) in comparison to the control. IL-8 secretion into the basolateral culture medium was increased at ZnO-NP concentrations of 5 μg/ml (P<0.05), as shown by ELISA. Our data indicates cyto- and genotoxic properties as well as a pro-inflammatory potential of ZnO-NPs in nasal mucosa cells. Thus, caution should be taken concerning their industrial and dermatological application. Additionally, further investigation on repetitive NP exposure is needed to estimate the impact of repair mechanisms.

Expression of SPLUNC1 protein in nasal polyp epithelial cells in air-liquid interface culture treated with IL-13

BACKGROUND

Short palate, lung, and nasal epithelium clone 1 (SPLUNC1) protein is an airway epithelial cell-derived molecule exerting host defense against pathogen. However, the function and regulation of SPLUNC1 in nasal epithelial cells are still unclear. Chronic rhinosinusitis with nasal polyps (CRSwNPs) is a disorder characterized by eosinophilic Th2 inflammation and frequent microbial colonization. The pathogenesis has been postulated as a disturbed mucosal immune response. This study investigates the SPLUNC1 expression of nasal polyp epithelial cells in air-liquid interface (ALI) culture and after treating with Th2 inflammatory cytokines IL-13.

METHODS

Human nasal polyp epithelial cells isolated from patients with CRSwNPs were put in different cell culture models at days 0 and 21 and were assessed for expression of SPLUNC1 by microarray. Cultured cells in ALI plus retinoic acid (ALI + RA) model were then incubated with 0, 1, 10, and 100 ng/mL human recombinant IL-13 for up to 5 days. The expression of SPLUNC1 was assessed by real-time quantitative polymerase chain reaction (RT-Q-PCR), reverse-transcriptase PCR (RT-PCR) and Western blot analysis.

RESULTS

ALI + RA culture model harvesting ciliary differentiated nasal epithelial cells constitutively expressed high levels of SPLUNC1. In contrast, SPLUNC1 is reduced under classic submerged single layer culture. SPLUNC1 is also dose-responsively down-regulated after incubation with IL-13.

CONCLUSION

A microenvironmental milieu containing IL-13 may be detrimental to the host innate immunity response, at least in part, through the inhibition of SPLUNC1 production.

Increased mucociliary differentiation of human respiratory epithelial cells on hyaluronan-derivative membranes

The selection of a scaffold to facilitate mucociliary differentiation of respiratory epithelial cells (RECs) is crucial in the development of tissue engineering of respiratory epithelium. However, how the differentiation of RECs is influenced by the biomaterials has never been thoroughly explored. Previously, hyaluronan derivatives were considered as unsuitable biomaterials for culture of respiratory epithelium. In contrast, this study demonstrates that the membranous scaffolds made from benzyl esters of hyaluronic acids are capable of providing a more preferential environment for human RECs than conventionally used collagen-based scaffolds. The proliferation and mucociliary differentiation of RECs were examined by MTT assays, scanning electron microscopy, immunofluorescence, immunoblotting and gene expression. The percentage of ciliated cells in cultured RECs increased from 12.4% on collagen to 20.4% on hyaluronan-derivative membranes with a pseudostratified polarized layer that closely resembled the composition of the native epithelium. The expression levels of MUC5AC and MUC5B mRNA were higher on hyaluronan-based scaffolds than those on collagen. The presence of a hyaluronan-binding domain, CD44 and the receptor for hyaluronan-mediated motility of RECs were also demonstrated. Accordingly, the mucociliary differentiation-promoting effect of hyaluronan-derivative membranes indicates that it may be applied to the tissue engineering of respiratory epithelium.

Culture of nasal epithelial cells using chitosan-based membranes

OBJECTIVES/HYPOTHESIS

The aim of this study was to evaluate whether chitosan-based membranes can be used as scaffolds for growth and differentiation of nasal epithelial cells (NECs). Our final goal was to establish a novel methodology for enhancing the regeneration of the respiratory system.

STUDY DESIGN

Prospective study.

METHODS

Human NECs were cultured on three various substrates, e.g., chitosan membranes, collagen, and chitosan-collagen membranes. Morphology of NECs was examined via light and electron microscopy, the area of ciliated cells was measured by confocal microscopy, and ciliary beat frequency was also evaluated. Expression of mucin genes was investigated with reverse-transcription polymerase chain reaction.

RESULTS

NECs were found to be successfully adhesive with collagen and chitosan-collagen membranes at day 3 after seeding, but not with chitosan membranes. The cilia area on collagen were 6.1% +/- 1.2%, 8.4% +/- 1.4%, and 12.5% +/- 1.9% at days 7, 14, and 21 after confluence, respectively, compared with 5.1% +/- 0.9%, 8.6% +/- 1.6%, and 12.3% +/- 2.1% in chitosan-collagen membranes, exhibited nonsignificant difference (P > .05). There were no significant differences in ciliary beat frequency between each group. The expression levels of mucin genes, namely, MUC5AC, MUC5B, and MUC2, in NECs on both collagen and chitosan-collagen membranes did not differ significantly (P > .05).

CONCLUSIONS

A small amount collagen mixed with chitosan substrate may improve the biocompatibility and promote the mucociliary differentiation in NECs. It appears that chitosan-collagen membrane is a promising scaffold for culture of the nasal epithelium, which sets the stage for studying tissue regeneration in the respiratory system.

Patients with positive allergen test have less favorable outcome after endoscopic microdebrider-assisted inferior turbinoplasty

BACKGROUND

Endoscopic microdebrider-assisted inferior turbinoplasty is a newly developed surgical technique to treat patients with nasal obstruction. Although the procedure has been reported to be safe and effective, we tested the hypothesis that the prognosis might deteriorate with time in allergic rhinitis patients as identified by a positive allergen test in patients who have a persistent regional inflammation of the nose. We assessed the degree of nasal obstruction in a prospective cohort to investigate whether positive allergen test predicts outcome.

METHODS

In 70 consecutive patients, the symptom of nasal obstruction was evaluated subjectively by a visual analog scale (VAS) and objectively by acoustic rhinometry using cross-sectional area of the second notch (CSA-2) and nasal cavity volume before operation, and 3 months, 12 months after operation, respectively. Then, patients were classified and compared according to the multiple-antigen simultaneous test (MAST).

RESULTS

Both MAST(+) and MAST(-) groups showed statistically significant improvement in VAS score, CSA-2, and nasal cavity volume at 12 months after operation (p < 0.01). Of note, MAST(+) patients showed less favorable results than MAST(-) patients at 12 months after operation (p < 0.05).

CONCLUSION

Microdebrider-assisted inferior turbinoplasty provides effective relief for patients with nasal obstruction. However, such turbinate surgery may be successful only for a short period of time in patients with allergic rhinitis. Our finding suggests that, in selecting appropriate candidates, surgeons should consider criteria other than symptomatology, especially in patients with allergic rhinitis who may have manifestations other than at the level of the inferior turbinate contributing to nasal blockage.