TIM-4 in macrophages contributes to nasal polyp formation through the TGF-ß1-mediated epithelial to mesenchymal transition in nasal epithelial cells.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is caused by prolonged inflammation of the paranasal sinus mucosa. The epithelial to mesenchymal transition (EMT) is involved in the occurrence and development of CRSwNP. The T-cell immunoglobulin domain and the mucin domain 4 (TIM-4) is closely related to chronic inflammation, but its mechanism in CRSwNP is poorly understood. In our study, we found that TIM-4 was increased in the sinonasal mucosa of CRSwNP patients and, especially, in macrophages. TIM-4 was positively correlated with α-SMA but negatively correlated with E-cadherin in CRS. Moreover, we confirmed that TIM-4 was positively correlated with the clinical parameters of the Lund-Mackay and Lund-Kennedy scores. In the NP mouse model, administration of TIM-4 neutralizing antibody significantly reduced the polypoid lesions and inhibited the EMT process. TIM-4 activation by stimulating with tissue extracts of CRSwNP led to a significant increase of TGF-ß1 expression in macrophages in vitro. Furthermore, coculture of macrophages and human nasal epithelial cells (hNECs) results suggested that the overexpression of TIM-4 in macrophages made a contribution to the EMT process in hNECs. Mechanistically, TIM-4 upregulated TGF-ß1 expression in macrophages via the ROS/p38 MAPK/Egr-1 pathway. In conclusion, TIM-4 contributes to the EMT process and aggravates the development of CRSwNP by facilitating the production of TGF-ß1 in macrophages. Inhibition of TIM-4 expression suppresses nasal polyp formation, which might provide a new therapeutic approach for CRSwNP.

IL-17A-producing sinonasal MAIT cells in patients with chronic rhinosinusitis with nasal polyps.

BACKGROUND: Diverse immune cells contribute to the pathogenesis of chronic rhinosinusitis (CRS), an inflammatory disease of the nasal cavity and paranasal sinuses. However, whether mucosal-associated invariant T (MAIT) cells are present in human sinonasal tissues remains unclear. Furthermore, the characteristics of sinonasal MAIT cells have not been studied in patients with CRS. OBJECTIVE: We investigated the phenotype, function, and clinical implications of MAIT cells in patients with CRS. METHODS: Peripheral blood and sinonasal tissue were obtained from patients with CRS with (CRSwNP) or without nasal polyps (CRSsNP) and healthy controls. MAIT cells were analyzed by flow cytometry. RESULTS: We found that MAIT cells are present in human sinonasal tissues from healthy controls and patients with CRS. The sinonasal MAIT cell population, but not peripheral blood MAIT cells, from patients with CRSsNP, noneosinophilic CRSwNP (NE-NP), or eosinophilic CRSwNP (E-NP) had a significantly higher frequency of activated cells marked by CD38 expression. In functional analysis, the sinonasal MAIT cell population from NE-NP and E-NP had a significantly higher frequency of IL-17A+ cells but lower frequency of IFN-γ+ or TNF+ cells than control sinonasal tissues. Furthermore, CD38 expression and IL-17A production by sinonasal MAIT cells significantly correlated with disease extent evaluated by the Lund-Mackay computed tomography score in patients with E-NP. CONCLUSIONS: Sinonasal MAIT cells exhibit an activated phenotype and produce higher levels of IL-17A in patients with CRSwNP. These alterations are associated with the extent of disease in patients with E-NP.

Reduced Expression of Antimicrobial Protein Secretory Leukoprotease Inhibitor and Clusterin in Chronic Rhinosinusitis with Nasal Polyps.

INTRODUCTION: Antimicrobial peptides and proteins (AMPs) constitute the first line of defense against pathogenic microorganisms in the airway. The association between AMPs and chronic rhinosinusitis with nasal polyps (CRSwNP) requires further investigations. This study is aimed at investigating the expression and regulation of major dysregulated AMPs in the nasal mucosa of CRSwNP. METHODS: The expression of AMPs was analyzed in nasal tissue from patients with eosinophilic (E) CRSwNP and nonECRSwNP and healthy subjects using RNA sequencing. The 10 most abundant AMPs expressed differentially in CRSwNP patients were verified by real-time PCR, and of these, the expression and regulation of secretory leukoprotease inhibitor (SLPI) and clusterin (CLU) were investigated further. RESULTS: The 10 most abundant AMPs expressed differentially in CRSwNP compared to healthy control, regardless of subtypes, included BPIFA1, BPIFB1, BPIFB2, CLU, LTF, LYZ, and SLPI, which were downregulated, and S100A8, S100A9, and HIST1H2BC, which were upregulated. ELISA and immunofluorescence confirmed the decreased expression of SLPI and CLU levels in CRSwNP. SLPI is expressed in both nasal epithelial cells and glandular cells, whereas CLU is mainly expressed in glandular cells. AB/PAS staining further demonstrated that both SLPI and CLU were mainly produced by mucous cells in submucosal glands. Furthermore, the numbers of submucosal glands were significantly decreased in nasal polyp tissue of CRSwNP compared to nasal tissue of controls. SLPI was downregulated by TGF-ß1 and IL-4 in cultured nasal tissues in vitro, while CLU expression was inhibited by TGF-ß1. Glucocorticoid treatment for 2 weeks significantly increased the expression of all downregulated AMPs, but not LYZ. Additionally, budesonide significantly increased the expression of SLPI and CLU in cultured nasal tissues. CONCLUSION: The expression of major antimicrobial proteins is significantly decreased in nasal tissue of CRSwNP. The expression of SLPI and CLU is correlated with the numbers of submucosal glands and regulated by inflammatory cytokines and glucocorticoids.

Subjective and Objective Measurements of Sinonasal Manifestations in Patients With Autoimmune Disorders.

OBJECTIVES/HYPOTHESIS: A number of autoimmune disorders (ADs) are associated with a spectrum of sinonasal manifestations comparable to chronic rhinosinusitis (CRS). Our objective was to study the subjective and objective measurements of sinonasal manifestations of ADs. STUDY DESIGN: Retrospective cohort study. METHODS: All patients with ADs referred to our tertiary care rhinology clinic from 2008 to 2019 with sinonasal symptoms were compared to randomly selected cohorts of noneosinophilic CRS without nasal polyps (neCRSsNP) and eosinophilic CRSsNP (eCRSsNP). Demographic data, along with the 22-item Sino-Nasal Outcome Test (SNOT-22), Lund-Kennedy (LK) endoscopy score, Lund-Mackay (LM) computed tomography (CT) score, nasal crusting, and epistaxis were reviewed at presentation. RESULTS: Fifty-three patients with an AD (26 with sarcoidosis, 14 with systemic lupus erythematosus, 10 with granulomatosis with polyangiitis [GPA], and three with pemphigoid vulgaris) were identified, and compared to 75 randomly selected neCRSsNP patients and 75 eCRSsNP patients. Patients with an AD had an average SNOT-22 score of 44.4 (confidence interval [CI]: 34.6-51.2) compared to 25 (CI: 24.4-25.1) and 29.7 (CI: 20.3-29.7) for neCRSsNP and eCRSsNP patients, respectively (P < .0001), and an average LK endoscopy score of 5.3 (CI: 4.3-6.3), compared to 3.4 (P = .005, CI: 2.7-4) in neCRSsNP and 4.4 in eCRSsNP (P = .2, CI: 3.7-5). There was no significant difference in the CT score compared to both groups. Patients with an AD also scored significantly worse on all four SNOT-33 subdomains, nasal obstruction, nasal crusting, and epistaxis. Additionally, patients with GPA had the worst symptomatic and endoscopy scores. CONCLUSIONS: Patients with ADs presenting with sinonasal symptoms have a more severe subjective and objective presentation than patients with CRS without nasal polyps. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:255-259, 2021.

Diverse phenotypes and endotypes of fungus balls caused by mixed bacterial colonization in chronic rhinosinusitis.

BACKGROUND: The pathogenic roles of fungus and bacteria in chronic rhinosinusitis (CRS) remain unclear. Recently, we described the bacterial ball, which is distinct from the fungus ball, as an unusual phenotype of bacterial infection. In this study, we investigated the clinical, histopathologic, and immunologic characteristics of sinonasal microorganic materials, including fungus ball and bacterial ball. METHODS: In this study, we enrolled 80 CRS patients with sinonasal microorganic materials and 10 control subjects who underwent skull base surgery or endoscopic dacryocystorhinostomy and had no signs or symptoms of nasal inflammation. All specimens were stained with hematoxylin-eosin, Gomori-methenamine-silver, and Gram stain to identify fungal organisms and Gram-positive/negative bacterial colonies. The expression of tumor necrosis factor (TNF)-α; interleukin (IL)-1ß; S100A7; S100A8/A9; and short, palate, lung, and nasal epithelial clone 1 (SPLUNC1) were evaluated by enzyme-linked immunosorbent assay using sinus lavage fluid. RESULTS: We histologically classified sinonasal microorganic materials into the following 4 groups: fungus ball (n = 45); bacterial ball (n = 6); mixed ball (formed by a mixture of fungus and bacteria, n = 27); and double ball (formed by separate fungal and bacterial balls, n = 2). Compared with the fungus ball, the mixed ball was more frequently detected in immunocompromised patients (p < 0.0001). In addition, TNF-α expression was significantly higher in fungus and mixed balls than in control, whereas the mixed ball showed higher expression of IL-1ß compared with the fungus ball. Moreover, the expression of S100A7 and S100A8/A9 protein in the mixed ball was significantly decreased when compared with the fungus ball, whereas there was no significant difference in SPLUNC1 expression between fungus and mixed balls. CONCLUSION: Our findings suggest that fungal and bacterial interactions are diverse in CRS. Specifically, the mixed ball is prevalent in CRS with an immunocompromised state and it may decrease epithelial barrier function.

Eosinophil extracellular trap formation is closely associated with disease severity in chronic rhinosinusitis regardless of nasal polyp status.

Chronic rhinosinusitis (CRS) is a heterogeneous inflammatory airway disease involving non-eosinophilic and eosinophilic phenotypes, which translate to various endotypes. Activated eosinophils and neutrophils are known to generate extracellular traps consisting of DNA and cytotoxic granule proteins. We sought to investigate the presence of eosinophil and neutrophil extracellular traps (EETs and NETs, respectively) in human CRS tissues and to clarify the associations with their clinical features. Nasal polyp (NP) or ethmoid tissue slides of 43 subjects from endoscopic sinus surgery for CRS were analysed. Quantitative analysis of EETs and NETs was performed by confocal microscopy using immunofluorescent staining. For correlation study, the presence of NPs, number of infiltrating tissue eosinophils, preoperative Lund-Mackay scores, and other comorbidities were analysed. EET formation was observed to varying degrees in all CRS groups and was correlated with the number of tissue eosinophils (r = 0.83, p < 0.001) regardless of the presence of NPs. Patients with more EETs demonstrated higher Lund-Mackay scores (r  =  0.51, p  = 0.009), blood eosinophilia (r  =  0.80, p  < 0.001), and decreased olfactory function (r  = -0.65, p  < 0.001). No correlation between the extent of EET formation and the presence of atopy or asthma was apparent. However, none of the CRS groups containing neutrophils formed NETs in this study. Eosinophilic CRS indicates the presence of EETs. Formation of EETs could have a role in clinical decision-making and prediction of treatment outcome of CRS, regardless of NP status.

Aspergillus fumigatus induction of IL-33 expression in chronic rhinosinusitis is PAR2-dependent.

OBJECTIVE: In the pathophysiology of chronic rhinosinusitis with nasal polyps (CRSwNP), Aspergillus fumigatus (A. fumigatus) can upregulate IL-33 from human sinonasal epithelial cells (SNECs), which then activates innate lymphoid cells causing release of IL-13, an important driver of allergic inflammation. However, the mechanism by which A. fumigatus mediates the induction of IL-33 expression remains to be elucidated. The objectives of this study were to determine the specific fungal component(s) and the receptor responsible for mediating the A. fumigatus induced increase in IL-33 expression in SNECs from patients with CRSwNP. METHODS: SNECs from CRSwNP patients were cultured and stimulated with various fungal components in the absence or presence of 4-(2-Aminoethyl)benzenesulfonyl fluoride hydrochloride, an irreversible serine protease inhibitor, or GB83, a reversible protease activated receptor 2 (PAR2) inhibitor. IL-33 expression was evaluated using quantitative real-time polymerase chain reaction (qRT-PCR). PAR2 expression was examined in inflamed mucosa from nonatopic control and CRSwNP patients. RESULTS: Elevation of IL-33 expression in primary SNECs was found in response to fungal protease but not fungal cell wall components. PAR2 expression was elevated in inflamed mucosa from CRSwNP patients in comparison to controls. The A. fumigatus fungal protease-mediated elevation in IL-33 expression by human SNECs was serine protease- and PAR2-dependent. CONCLUSION: These data suggest that serine protease activity of A. fumigatus is capable of inducing IL-33 expression in CRSwNP SNECs via PAR2, a potential therapeutic target in the treatment of CRSwNP. LEVEL OF EVIDENCE: NA Laryngoscope, 129:2230-2235, 2019.

Induction of human regulatory innate lymphoid cells from group 2 innate lymphoid cells by retinoic acid.

BACKGROUND: Group 2 innate lymphoid cells (ILC2s) play critical roles in induction and exacerbation of allergic airway inflammation. Thus clarification of the mechanisms that underlie regulation of ILC2 activation has received significant attention. Although innate lymphoid cells are divided into 3 major subsets that mirror helper effector T-cell subsets, counterpart subsets of regulatory T cells have not been well characterized. OBJECTIVE: We sought to determine the factors that induce regulatory innate lymphoid cells (ILCregs). METHODS: IL-10+ ILCregs induced from ILC2s by using retinoic acid (RA) were analyzed with RNA-sequencing and flow cytometry. ILCregs were evaluated in human nasal tissue from healthy subjects and patients with chronic rhinosinusitis with nasal polyps and lung tissue from house dust mite- or saline-treated mice. RESULTS: RA induced IL-10 secretion by human ILC2s but not type 2 cytokines. IL-10+ ILCregs, which were converted from ILC2s by means of RA stimulation, expressed a regulatory T cell-like signature with expression of IL-10, cytotoxic T lymphocyte-associated protein 4, and CD25, with downregulated effector type 2-related markers, such as chemoattractant receptor-homologous molecule on TH2 cells and ST2, and suppressed activation of CD4+ T cells and ILC2s. ILCregs were rarely detected in human nasal tissue from healthy subjects or lung tissue from saline-treated mice, but numbers were increased in nasal tissue from patients with chronic rhinosinusitis with nasal polyps and in lung tissue from house dust mite-treated mice. Enzymes for RA synthesis were upregulated in airway epithelial cells during type 2 inflammation in vivo and by IL-13 in vitro. CONCLUSION: We have identified a unique immune regulatory and anti-inflammatory pathway by which RA converts ILC2s to ILCregs. Interactions between airway epithelial cells and ILC2s play an important roles in the generation of ILCregs.

Chronic rhinosinusitis in elderly patients is associated with an exaggerated neutrophilic proinflammatory response to pathogenic bacteria.

BACKGROUND: Potential effects of aging on chronic rhinosinusitis (CRS) pathophysiology have not been well defined but might have important ramifications given a rapidly aging US and world population. OBJECTIVE: The goal of the current study was to determine whether advanced age is associated with specific inflammatory CRS endotypes or immune signatures. METHODS: Levels of 17 mucus cytokines and inflammatory mediators were measured in 147 patients with CRS. Hierarchical cluster analysis was used to identify and characterize inflammatory CRS endotypes, as well as to determine whether age was associated with specific immune signatures. RESULTS: A CRS endotype with a proinflammatory neutrophilic immune signature was enriched in older patients. In the overall cohort patients 60 years and older had increased mucus levels of IL-1ß, IL-6, IL-8, and TNF-α when compared with their younger counterparts. Increases in levels of proinflammatory cytokines were associated with both tissue neutrophilia and symptomatic bacterial infection/colonization in aged patients. CONCLUSIONS: Aged patients with CRS have a unique inflammatory signature that corresponds to a neutrophilic proinflammatory response. Neutrophil-driven inflammation in aged patients with CRS might be less likely to respond to corticosteroids and might be closely linked to chronic microbial infection or colonization.

Relative abundance of nasal microbiota in chronic rhinosinusitis by structured histopathology.

BACKGROUND: Chronic rhinosinusitis (CRS) is an inflammatory disease process with several different phenotypes. Recent data has shown that CRS phenotypes maintain distinct nasal microbiota that may predict surgical outcomes. Nasal microbiota and structured histopathologic reporting have the potential to further differentiate subtypes and provide additional insight into the pathophysiology of CRS. METHODS: Sinus swabs collected during functional endoscopic sinus surgery (FESS) were studied by polymerase chain reaction analysis of 16S ribosomal RNA. A structured histopathology report of 13 variables was utilized to analyze sinus tissue removed during FESS. Histopathology variables and relative abundance of nasal microbiota were compared among CRS patients. RESULTS: A total of 51 CRS patients who underwent FESS were included. Relative abundance of the Firmicutes phylum in nasal microbiota of CRS patients was associated with presence of neutrophilic infiltrate (27.47 ± 44.75 vs 9.21 ± 11.84, p < 0.029), presence of mucosal ulceration (47.67 ± 45.52 vs 13.27 ± 26.48, p < 0.041), presence of squamous metaplasia (5562.70 ± 2715.66 vs 3563.73 ± 2580.84, p < 0.035), and absence of Charcot-Leyden crystals (5423.00 ± 3320.57 vs 679.94 ± 1653.66, p < 0.001). Relative abundance of the Bacteroidetes phylum in nasal microbiota of CRS patients was associated with increased severity of inflammatory degree (p < 0.004) and presence of mucosal ulceration (p < 0.004). CONCLUSION: Distinct histopathologic features of CRS are associated with relative abundance of nasal microbiota phyla, specifically Firmicutes and Bacteroidetes. These findings contribute to the growing body of literature on microbiota in sinonasal disease and may have important implications for understanding pathophysiologic mechanisms of CRS subtypes and disease management.

Immunoglobulin G4-related disease of the paranasal sinuses.

Immunoglobulin G4-related disease (IgG4-RD) is becoming increasingly documented. It was first described in relation to autoimmune pancreatitis. Features of the disease include tissue infiltration by IgG4 plasma cells with associated fibrosis and the growth of pseudotumours. A 71-year-old woman presented with increasing right cheek swelling and mild proptosis. Ten years earlier, she had a similar presentation and was diagnosed with an inflammatory pseudotumour. Examination revealed a lesion in the right nasal cavity. CT and MRI confirmed a mass within the right maxillary antrum extending into the nasal cavity. Endoscopic biopsies showed florid plasma cell infiltrate with marked increase in IgG+ plasma cells. Immunostaining expressed IgG4 (70%). She was started on a course of prednisolone and her symptoms resolved. IgG4-RD is becoming an emerging disease entity. Its involvement in the paranasal sinuses can mimic nasal tumours. Major surgical resection should be avoided as patients can often be treated medically.

Focus on the Involvement of the Nose and Paranasal Sinuses in Eosinophilic Granulomatosis with Polyangiitis (Churg-Strauss Syndrome): Nasal Cytology Reveals Infiltration of Eosinophils as a Very Common Feature.

BACKGROUND: Eosinophilic granulomatosis with polyangiitis (EGPA) is a necrotizing vasculitis that predominantly affects small- to medium-sized vessels. It is characterized by a wide spectrum of extrapulmonary symptoms, including sinonasal and paranasal sinus abnormalities. These are the most common features of this disease, constituting diagnostic criteria for EGPA. However, the actual clinical features, cellular mechanisms and impact on patients' quality of life (QoL) are still a matter of study. METHODS: Thirty-nine EGPA patients underwent multidimensional rhinological evaluations, including rhinofibroscopy, nasal cytology, and QoL questionnaires. This was coupled with respiratory and rheumatological assessments. RESULTS: Twenty-eight patients were diagnosed with chronic rhinosinusitis (CRS). Of these, 18 had nasal polyposis (NP). Chronic rhinitis was diagnosed in 10 patients. Of these, 3 had allergic rhinitis (AR) and seven had non-AR (NAR). Overall, only 1 patient (2.6%) was normal. Nasal cytology showed that hypereosinophilia was present in 17/28 patients with CRS, 4/7 patients with NAR and all patients with AR. SNOT-22 and SF-36 showed a severe impact of nasal symptoms on QoL. No differences in asthma control or rheumatological patterns for EGPA were observed among patients with or without NP. CONCLUSIONS: Even when the rheumatological assessment scored EGPA "under control" according to the Birmingham Vasculitis Activity Score and Vasculitis Damage Index, sinonasal diseases and related nasal inflammatory processes were not controlled. Therefore, there is a need for clinical monitoring and targeted treatment to control the inflammatory processes and improve the QoL of EGPA patients.

Sinonasal T-cell expression of cytotoxic mediators granzyme B and perforin is reduced in patients with chronic rhinosinusitis.

BACKGROUND: CD8+ T cells and natural killer (NK) cells are cytotoxic cells that use granzyme B (GrB) and perforin. Defective cytotoxic function is known to play a role in dysregulated immune response as seen in chronic sinusitis, also referred to as chronic rhinosinusitis (CRS). However, to our knowledge, in the United States, neither GrB or perforin expression has been reported in patients with CRS. OBJECTIVE: The aim of this study was to investigate sinonasal cytotoxic cells, their mediators, and cell-specific distribution of these mediators in patients with CRS with nasal polyp (CRSwNP) and in patients with CRS without nasal polyp (CRSsNP). METHODS: Blood and sinus tissue samples were taken from patients with CRSsNP (n = 8) and CRSwNP (n = 8) at the time of surgery. Control subjects (n = 8) underwent surgery for cerebrospinal fluid leak repair or to remove non-hormone-secreting pituitary tumors. The cells were analyzed via flow cytometry by using CD8 expression to identify cytotoxic T cells and CD56 expression to identify NK cells. Intracellular GrB and perforin expression were analyzed with flow cytometry. RESULTS: We observed no significant differences in plasma or peripheral blood immune cell numbers or specific levels of GrB or perforin among the groups. In the sinonasal mucosa of the patients with CRSsNP and the patients with CRSwNP, there was a significant decrease in GrB and perforin levels (p < 0.05) despite similar or increased numbers of cytotoxic cells when compared with the controls. The overall decrease in GrB and perforin in the sinonasal mucosa of the patients with CRSsNP and the patients with CRSwNP was due to decreased T cell production. There was no difference in total NK cell count or expression of perforin or GrB among all the groups. CONCLUSION: Total levels of sinonasal GrB and perforin were decreased in the sinonasal mucosa of both the patients with CRSwNP and the patients with CRSsNP compared with the controls, whereas sinonasal CD8+ T cells, (but not NK cells,), intracellular stores of GrB and perforin were reduced in the patients with CRSwNP compared with the controls.

Expression of immunoglobulin D is increased in chronic rhinosinusitis.

BACKGROUND: Immunoglobulin (Ig) D is largely localized to the upper airway and reacts with colonizing respiratory pathogens. OBJECTIVE: To determine whether chronic rhinosinusitis (CRS) is associated with increased IgD expression. METHODS: We performed immunofluorescent staining for cytoplasmic IgD, IgA, IgM, and surface plasma cell marker CD138 (syndecan-1) in sinus tissue of patients with CRS with and without nasal polyps (CRSwNP and CRSsNP, respectively) and control subjects without CRS (n = 6 each). Sinonasal mucus antibody levels of patients with CRSwNP or CRSsNP and control subjects were measured by enzyme-linked immunosorbent assay (n = 13, 11, and 9 subjects, respectively). Cells per square millimeter and antibody levels were compared by analysis of variance. Histopathology was performed with sinus tissue from subjects in the 3 groups (n = 6, 8, and 13 subjects respectively). RESULTS: Cells expressing cytoplasmic IgD exceeded those with cytoplasmic IgA and IgM and represented most CD138+ plasma cells in the lamina propria. The frequencies of IgD+ plasma cells were significantly higher in patients with CRSsNP and CRSwNP compared with control subjects (P < .01). Only patients with CRSwNP showed increased frequencies of IgM and IgA plasma cells (P < .01). In contrast to high plasma cell frequencies in tissues, the levels of secreted IgD were lower than those of IgA, IgM, and IgG but were highest in the CRSwNP group compared with the other groups (P < .05). CONCLUSION: IgD plasma cells are prominent in sinus tissues and are increased in CRS. That IgD protein also shows the lowest concentration of antibodies in secretions suggests that its activity might be targeted to the tissue rather than secretions.

Nasal interleukin 25 as a novel biomarker for patients with chronic rhinosinusitis with nasal polyps and airway hypersensitiveness: A pilot study.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory disease of the upper airway and is tightly linked with airway hyperresponsiveness (AHR) and asthma. However, the surrogate biomarkers for indicating AHR and asthma in patients with CRSwNP remain elusive. OBJECTIVE: To investigate the surrogate biomarkers for indicating AHR and asthma in patients with CRSwNP. METHODS: In this study, sinonasal tissues were collected from 42 patients with CRSwNP (asthma, n = 17; asymptomatic AHR, n = 11; non-AHR, n = 14), 11 patients with chronic rhinosinusitis without nasal polyps (CRSsNP), and 13 controls. The protein and messenger RNA levels of interleukin (IL) 25 and other cytokines in nasal polyp (NP) and control sinonasal tissues were determined by quantitative real-time polymerase chain reaction and multiplex immunoassay, respectively. Multivariate logistic regression and receiver operating characteristic curve analysis were performed to assess the clinical relevance of IL-25. RESULTS: We found that the protein and messenger RNA levels of IL-25 were significantly increased in NP tissues compared with the control sinonasal tissues from patients with CRSwNP, patients with CRSsNP, and controls. Multivariate logistic regression revealed that the nasal IL-25 protein level and nasal and blood eosinophil counts were independent risk factors for AHR in patients with CRSwNP. According to receiver operating characteristic curve analysis, nasal tissue IL-25 had a sensitivity of 91.4% and a specificity of 62.8% (area under the curve, 0.845) at the cutoff level of 5 pg/µL for indicating AHR in this CRSwNP cohort. CONCLUSION: Our findings indicated that IL-25 was significantly increased in NP tissues and may be considered as the molecular indicator for AHR in patients with CRSwNP. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02110654.

Novel role of surfactant protein A in bacterial sinusitis.

BACKGROUND: Chronic rhinosinusitis (CRS) is a common inflammatory disorder of the upper airway characterized by chronic inflammation and significant sinonasal remodeling. CRS is comprised of 2 major subgroups, based on whether polyps are present or absent. In some cases, it is characterized by colonization with opportunistic pathogens such as Pseudomonas aeruginosa (PA), Staphylococcus aureus, and other bacteria. The innate immune system of the sinonasal epithelium is the first line of defense against inhaled pathogens. Surfactant protein A (SP-A) is a member of the collectin family secreted by the airway epithelia and plays a critical role in airway innate immunity, as it can aggregate bacteria. We hypothesized that SP-A plays a role in bacterial CRS. METHODS: Air-liquid interface (ALI) cultures of nasal epithelial cells were derived from human ex-vivo healthy and CRS sinus tissues (n = 26) and challenged with PA. SP-A levels were measured with western blot and quantitative reverse transcript-polymerase chain reaction (qRT-PCR) in ALI and sinus tissues. RESULTS: We determined that SP-A: (i) mRNA and protein levels are increased significantly in CRS tissues compared with healthy sinuses; (ii) although primarily expressed in the lung, it is also synthesized and expressed in sinonasal epithelia; (ii) is expressed in the sinuses of an SP-A humanized transgenic mouse but not in SP-A knockout mice; (iv) mRNA levels are upregulated significantly during PA challenge, but protein levels are downregulated 4 hours postchallenge and upregulated at 12 hours. CONCLUSION: Our data suggest that SP-A is expressed in the sinuses and that it plays a role in the sinus innate immune responses during bacterial infections.

Impact of tobacco smoke on upper airway dendritic cell accumulation and regulation by sinonasal epithelial cells.

BACKGROUND: In these studies we examined the impact of environmental tobacco smoke (ETS) and active smoking on sinonasal dendritic cell (DC) subsets in controls or patients with chronic rhinosinusitis with nasal polyps (CRSwNP). In subsequent in-vitro investigations, we examined the influence of cigarette smoke extract (CSE) on human sinonasal epithelial cells' (HSNECs) ability to regulate DC functions. METHODS: Sinonasal tissue, blood, and hair were collected from patients undergoing sinus surgery. Smoking status and ETS exposure were determined by hair nicotine. DC subsets were examined by flow cytometric analysis. Monocyte-derived dendritic cells (moDCs) were treated with conditioned medium from non-smoked-exposed HSNECs (NS-HSNECs) or cigarette-smoke-extract-exposed HSNECs (CSE-HSNECs) to assess the impact of CSE exposure on HSNEC regulation of moDC functions. RESULTS: Control subjects who were active smokers displayed increased sinonasal moDC and myeloid dendritic 1 (mDC1) cells and reduced mDC2 cells, whereas, in CRSwNP patients, only moDC and mDC2 cells were altered. ETS was found to increase only moDCs in the CRSwNP patients. In vitro, CSE stimulated HSNEC secretion of the moDC regulatory products chemokine (C-C motif) ligand 20, prostaglandin E2 , and granulocyte-macrophage colony-stimulating factor. CSE exposure also promoted HSNECs to stimulate monocyte and moDC migration. moDCs treated with CSE-HSNEC media stimulated an increase in antigen uptake and expression of CD80 and CD86. Last, CSE-HSNEC-treated moDCs secreted increased levels of interleukin-10, interferon-γ, and thymic stromal lymphopoietin. CONCLUSION: Active smoking, and to a lesser degree ETS, alters the sinonasal composition of DCs. A potential mechanism to account for this is that cigarette smoke stimulates HSNECs to induce moDC migration, maturation, and activation.

Taste Receptors Mediate Sinonasal Immunity and Respiratory Disease.

The bitter taste receptor T2R38 has been shown to play a role in the pathogenesis of chronic rhinosinusitis (CRS), where the receptor functions to enhance upper respiratory innate immunity through a triad of beneficial immune responses. Individuals with a functional version of T2R38 are tasters for the bitter compound phenylthiocarbamide (PTC) and exhibit an anti-microbial response in the upper airway to certain invading pathogens, while those individuals with a non-functional version of the receptor are PTC non-tasters and lack this beneficial response. The clinical ramifications are significant, with the non-taster genotype being an independent risk factor for CRS requiring surgery, poor quality-of-life (QOL) improvements post-operatively, and decreased rhinologic QOL in patients with cystic fibrosis. Furthermore, indirect evidence suggests that non-tasters also have a larger burden of biofilm formation. This new data may influence the clinical management of patients with infectious conditions affecting the upper respiratory tract and possibly at other mucosal sites throughout the body.

Allergic sensitization does not predispose to sinus inflammation in externalized paranasal sinuses.

BACKGROUND: Chronic rhinosinusitis (CRS) has a multifactorial etiology, with a debate about the role of inhalant allergy in the pathogenesis of CRS. OBJECTIVE: This study assessed the impact of allergy status on externalized paranasal sinuses after tumor resection to determine if a predisposition to inhalant allergy brought about additional inflammation after sinus surgery. METHODOLOGY: A case-control study was performed on patients who had no history of CRS who underwent paranasal sinus tumor resection. Allergic sensitization was defined by a positive serum ImmunoCAP test result. Outcomes were measured at least 6 months after surgery by using the modified Lund-MacKay endoscopic score and the 22-item Sino-Nasal Outcome test, with rhinitis, sleep, psychological, ear and/or facial, and sinus subscores to assess the impact of allergy status on mucosal inflammation. RESULTS: A total of 103 patients (53.44 ± 17.46 years; 46% women) were assessed. Of these, 61.17% were allergically sensitized at the time of surgery. Postsurgery endoscopic assessment was similar [the modified Lund-Mackay endoscopic score allergic sensitized 0.5 (1.7) versus nonallergic sensitized 0.0 (0.9); p = 0.15]. Sinonasal symptoms were also similar between the groups' 22-item Sino-Nasal Outcome test scores, allergic sensitized versus allergic nonsensitized, (allergic 28.9 ± 20.8 versus nonallergic 33.5 ± 19.7; p = 0.31), rhinitis score (5.9 ± 5.5 versus 6.4 ± 4.7; p = 0.66), sleep score (6.9 ± 5.9 versus 7.7 ± 4.8; p = 0.50), ear and/or facial symptom score (3.4 ± 3.6 versus 4.3 ± 3.3; p = 0.22), psychological score (6.9 ± 6.0 versus 8.3 ± 6.7; p = 0.29), and of nasal symptom score (6.4 ± 5.2 versus 7.0 ± 5.3; p = 0.61). CONCLUSIONS: Externalization of the sinuses in patients with inhalant allergy did not bring about significant additional inflammation in patients after tumor surgery.