Predicting Obstructive Sleep Apnea Based on Computed Tomography Scans Using Deep Learning Models.

Rationale: The incidence of clinically undiagnosed obstructive sleep apnea (OSA) is high among the general population because of limited access to polysomnography. Computed tomography (CT) of craniofacial regions obtained for other purposes can be beneficial in predicting OSA and its severity. Objectives: To predict OSA and its severity based on paranasal CT using a three-dimensional deep learning algorithm. Methods: One internal dataset (N = 798) and two external datasets (N = 135 and N = 85) were used in this study. In the internal dataset, 92 normal participants and 159 with mild, 201 with moderate, and 346 with severe OSA were enrolled to derive the deep learning model. A multimodal deep learning model was elicited from the connection between a three-dimensional convolutional neural network-based part treating unstructured data (CT images) and a multilayer perceptron-based part treating structured data (age, sex, and body mass index) to predict OSA and its severity. Measurements and Main Results: In a four-class classification for predicting the severity of OSA, the AirwayNet-MM-H model (multimodal model with airway-highlighting preprocessing algorithm) showed an average accuracy of 87.6% (95% confidence interval [CI], 86.8-88.6%) in the internal dataset and 84.0% (95% CI, 83.0-85.1%) and 86.3% (95% CI, 85.3-87.3%) in the two external datasets, respectively. In the two-class classification for predicting significant OSA (moderate to severe OSA), the area under the receiver operating characteristic curve, accuracy, sensitivity, specificity, and F1 score were 0.910 (95% CI, 0.899-0.922), 91.0% (95% CI, 90.1-91.9%), 89.9% (95% CI, 88.8-90.9%), 93.5% (95% CI, 92.7-94.3%), and 93.2% (95% CI, 92.5-93.9%), respectively, in the internal dataset. Furthermore, the diagnostic performance of the Airway Net-MM-H model outperformed that of the other six state-of-the-art deep learning models in terms of accuracy for both four- and two-class classifications and area under the receiver operating characteristic curve for two-class classification (P < 0.001). Conclusions: A novel deep learning model, including a multimodal deep learning model and an airway-highlighting preprocessing algorithm from CT images obtained for other purposes, can provide significantly precise outcomes for OSA diagnosis.

NLRP3 inhibition attenuates the allergic rhinitis symptoms in a mouse model.

BACKGROUND: Recent human and animal studies have demonstrated that Nod-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome is closely involved in the development of allergic diseases. OBJECTIVE: To identify the mechanism underlying the activation of NLRP3 inflammasome signaling pathway in an ovalbumin (OVA)-induced allergic rhinitis (AR) mice model and to validate the effect of a specific inhibitor of the NLRP3, MCC950. METHODS: Mice were divided into three groups and each group consisted of ten mice (saline group, the negative control group; OVA group, the OVA-induced AR model group; and OVA+MCC group, treated with 10 mg/kg MCC950). MCC950 was administered intraperitoneally every second day. Multiple parameters of AR, including NLRP3, caspase-1, interleukin (IL)-1ß, and IL-18 were evaluated by using ELISA, RT-qPCR, histopathology, and immunohistochemistry. RESULTS: The mRNA and protein levels of NLRP3, caspase-1, IL-1ß and IL-18 were upregulated in the OVA group compared with those of the saline group. MCC950 significantly inhibited the mRNA and protein levels of NLRP3, caspase-1, IL-1ß and IL-18 in nasal tissue. Further, AR symptoms and eosinophil count were normalized after MCC950 treatment. However, OVA-specific IgE was not restored in the OVA+MCC group. CONCLUSION: NLRP3 inflammasome signaling pathway may be an alternative pathway to induce AR symptoms in OVA-induced AR model. MCC950 is a specific inhibitor of NLRP3 cascade, which attenuates AR symptoms regardless of IgE.

Symbiotic microbiome Staphylococcus epidermidis restricts IL-33 production in allergic nasal epithelium via limiting the cellular necroptosis.

BACKGROUND: Allergic rhinitis (AR) is characterized by airway inflammation in nasal mucosa from inhaled allergens and interleukin (IL)-33 is the potent inducer of Th2 inflammation in allergic nasal epithelium. Staphylococcus epidermidis is one of the most abundant colonizers of the healthy human nasal mucosa and might impact the allergen-induced inflammatory responses in the nasal epithelium. Thus, we sought to characterize the mechanism of S. epidermidis regulating Th2 inflammation and IL-33 production in AR nasal mucosa. RESULTS: The AR symptoms were alleviated and eosinophilic infiltration, serum IgE levels, and Th2 cytokines were significantly decreased in OVA-sensitized AR mice in response to human nasal commensal S. epidermidis. The inoculation of S. epidermidis to normal human nasal epithelial cells reduced IL-33 and GATA3 transcriptions and also reduced IL-33 and GATA3 expression in AR nasal epithelial (ARNE) cells and the nasal mucosa of AR mice. Our data exhibited that the cellular necroptosis of ARNE cells might be involved in IL-33 production and inoculation of S. epidermidis decreased the phosphorylation of necroptosis enzymes in ARNE cells, which was related to the reduction of IL-33 production. CONCLUSIONS: We present that human nasal commensal S. epidermidis reduces allergic inflammation by suppressing IL-33 production in nasal epithelium. Our findings indicate that S. epidermidis serves a role in blocking allergen-induced cellular necroptosis in allergic nasal epithelium which might be a key mechanism of reduction of IL-33 and Th2 inflammation.

Der p 38 Is a Bidirectional Regulator of Eosinophils and Neutrophils in Allergy.

The house dust mite is the most common cause of allergic diseases, and TLR4 acts as an overarching receptor for allergic responses. This study aimed to identify novel allergen binding to TLR4 in house dust mites and unveil its unique role in allergic responses. Der p 38 was purified and characterized by liquid chromatography tandem mass spectrometry-based peptide mapping. Biolayer interferometry and structure modeling unveiled TLR4-binding activity and the structure of recombinant Der p 38. The allergenicity of Der p 38 was confirmed by a skin prick test, and basophil activation and dot blot assays. The skin prick test identified 24 out of 45 allergic subjects (53.3%) as Der p 38+ subjects. Der p 38-augmented CD203c expression was noted in the basophils of Der p 38+ allergic subjects. In animal experiments with wild-type and TLR4 knockout BALB/c mice, Der p 38 administration induced the infiltration of neutrophils as well as eosinophils and exhibited clinical features similar to asthma via TLR4 activation. Persistent Der p 38 administration induced severe neutrophil inflammation. Der p 38 directly suppressed the apoptosis of allergic neutrophils and eosinophils, and enhanced cytokine production in human bronchial epithelial cells, inhibiting neutrophil apoptosis. The mechanisms involved TLR4, LYN, PI3K, AKT, ERK, and NF-κB. These findings may contribute to a deep understanding of Der p 38 as a bridge allergen between eosinophilic and neutrophilic inflammation in the pathogenic mechanisms of allergy.

Sleep parameter characteristics of patients with OSA who have retropalatal circumferential narrowing and the clinical significance of lateral pharyngeal wall collapse during sleep.

BACKGROUND: The lateral pharyngeal wall (LPW) is a critical anatomic structure in patients with obstructive sleep apnea (OSA). Resolving the retropalatal circumferential (RC) narrowing caused by combination of both LPW collapse and antero-posterior (AP) narrowing holds promise for surgical treatment of OSA. We sought to determine the clinical characteristics and distinctive alterations in sleep parameters of patients with OSA who have RC narrowing and LPW collapse. METHODS: Drug-induced sleep endoscopy (DISE), polysomnography findings, and sleep questionnaires were reviewed retrospectively in patients with OSA. RESULTS: Of the 106 OSA patients examined, 48% showed RC narrowing and 44% showed AP narrowing at the oropharynx level during sleep while 8% of the patients showed only LPW collapse. Patients with RC narrowing with LPW collapse exhibited a higher BMI than those with AP narrowing only. In addition, patients with RC narrowing showed more aggravated sleep parameters including apneic events than patients with AP narrowing alone. The degree of RC narrowing correlated significantly with the severity of OSA as shown by a higher apnea index and lower oxygen desaturations. CONCLUSIONS: Our clinical findings suggest that the presence of RC narrowing with LPW collapse in OSA is closely related to increased apneic and oxygen desaturation events. RC narrowing with LPW collapse may be targets for surgical correction in patients with OSA to improve therapeutic outcomes.

DEP-induced ZEB2 promotes nasal polyp formation via epithelial-to-mesenchymal transition.

BACKGROUND: Diesel exhaust particles (DEPs) are associated with the prevalence and exacerbation of allergic respiratory diseases, including allergic rhinitis and allergic asthma. However, DEP-induced mechanistic pathways promoting upper airway disease and their clinical implications remain unclear. OBJECTIVE: We sought to investigate the mechanisms by which DEP exposure contributes to nasal polyposis using human-derived epithelial cells and a murine nasal polyp (NP) model. METHODS: Gene set enrichment and weighted gene coexpression network analyses were performed. Cytotoxicity, epithelial-to-mesenchymal transition (EMT) markers, and nasal polyposis were assessed. Effects of DEP exposure on EMT were determined using epithelial cells from normal people or patients with chronic rhinosinusitis with or without NPs. BALB/c mice were exposed to DEP through either a nose-only exposure system or nasal instillation, with or without house dust mite, followed by zinc finger E-box-binding homeobox (ZEB)2 small hairpin RNA delivery. RESULTS: Bioinformatics analyses revealed that DEP exposure triggered EMT features in airway epithelial cells. Similarly, DEP-exposed human nasal epithelial cells exhibited EMT characteristics, which were dependent on ZEB2 expression. Human nasal epithelial cells derived from patients with chronic rhinosinusitis presented more prominent EMT features after DEP treatment, when compared with those from control subjects and patients with NPs. Coexposure to DEP and house dust mite synergistically increased the number of NPs, epithelial disruptions, and ZEB2 expression. Most importantly, ZEB2 inhibition prevented DEP-induced EMT, thereby alleviating NP formation in mice. CONCLUSIONS: Our data show that DEP facilitated NP formation, possibly via the promotion of ZEB2-induced EMT. ZEB2 may be a therapeutic target for DEP-induced epithelial damage and related airway diseases, including NPs.

Optimal application of soft-palate webbing flap pharyngoplasty combined with nasal surgery for surgical treatment of primary snoring and obstructive sleep apnea.

BACKGROUND: Excessive collapse of the soft palate and lateral pharyngeal wall narrowing are established causes of loud snoring and sleep apnea in subjects with obstructive sleep apnea (OSA). Therefore, delicate surgical techniques are needed to reshape the soft palate and create sufficient tension in the lateral pharyngeal wall. This study aimed to determine the therapeutic outcome and favorable indications of soft-palate webbing flap pharyngoplasty in subjects with OSA and primary snoring. METHODS: A total of 174 subjects who underwent soft-palate webbing flap pharyngoplasty combined with uvulopalatal flap and septoturbinoplasty from August 2015 to February 2020 were included in this study. Medical records, including pre- and postoperative sleep parameters, were retrospectively reviewed. The primary outcome measure was the degree of improvement in AHI after surgery. Other outcomes were differences in surgical response rates, subjective visual analog score (VAS) for snoring, sleep quality, and complications. RESULTS: Polysomnographic results showed that apnea-hypopnea index (AHI) scores were significantly reduced from 39.6 ± 6.1 to 22.9 ± 3.6 following soft-palate webbing flap pharyngoplasty in 59 subjects, and overall success and response rates of this technique were analyzed with 71%. We found that the successful outcomes were observed in 50% of mild (n = 12) and 56% of moderate (n = 16) subjects with OSA subjects due to lateral pharyngeal wall collapse. The success rate of soft-palate webbing flap pharyngoplasty was relatively higher in subjects with mild and moderate OSA than those with severe OSA. Additionally, the mean VAS snoring scale was 4.7 and subjects' primary snoring intensity significantly improved to 2.9 after soft-palate webbing flap pharyngoplasty. Subjective symptoms such as daytime sleepiness and sleep quality also showed improvement. Most complications were found to be minimal and improved by 1 month after the operation. CONCLUSION: Our data demonstrate that soft-palate webbing flap pharyngoplasty is an effective treatment for OSA and primary snoring and may be a promising technique to reduce lateral pharyngeal wall collapse.

Correlation of site of obstruction between two dynamic evaluation modalities in obstructive sleep apnea patients: drug-induced sleep endoscopy and sleep videofluoroscopy.

PURPOSE: Drug-induced sleep endoscopy (DISE) and sleep videofluoroscopy (SVF) are two dynamic modalities for evaluating the upper airway in patients with obstructive sleep apnea (OSA). We evaluated the correlation of obstructive sites determined by DISE and SVF in OSA patients and elucidate findings that can improve the accuracy of upper airway assessment. METHODS: A consecutive series of 63 patients with OSA who underwent DISE and SVF were the subjects of this study. The DISE and SVF findings were divided according to the anatomical structure responsible for the collapse, including the soft palate (SP), oropharyngeal lateral walls (LW), tongue base (TB), and larynx (LX). The obstruction was graded on the three-point scale: 0, no obstruction; 1, partial obstruction; or 2, complete obstruction. Additionally, grade 1.5 TB obstruction was designated when the posterior displacement of the anterior tongue was detected during simultaneous retropalatal obstruction. The agreement rate and Cohen's kappa test between the two modalities were also assessed. RESULTS: The agreement rate between the two modalities was highest in LX (88.9%) followed by SP (85.7%), TB (76.1%), and LW (74.6%) (Cohen's kappa value = 0.757 in LX, 0.642 in SP, 0.637 in TB, 0.612 in LW, respectively). When grade 1.5 and 2 TB obstructions were combined, the agreement rate increased to 88.9% (Cohen's kappa value = 0.757). CONCLUSIONS: We found a good overall agreement between the two dynamic airway evaluation modalities during drug-induced sleep, and this correlation may be improved if the posterior displacement of the anterior tongue during DISE is used as a sign of TB obstruction.

IL-17C Protects Nasal Epithelium from Pseudomonas aeruginosa Infection.

IL-17 family cytokines are directly involved in host immune responses and the critical mediators for host defense against infection or inflammation. IL-17C is highly expressed in respiratory epithelium and is induced after acute bacterial lung infection. However, the definite function of IL-17C induced by Pseudomonas aeruginosa (PAO1 strain) is not fully understood, and our study was designed to demonstrate IL-17C-induced immune response against PAO1 infection in nasal epithelium. Passage-2 normal human nasal epithelial (NHNE) cells were infected with PAO1 and the relationship between IL-17C-related immune responses and the iron absorption of PAO1, depending on inoculation of recombinant human IL-17C (rhIL-17C), was assessed by measuring the siderophore activity of PAO1. Microarray data showed that IL-17C expression increased 34.7 times at 8 hours postinfection (hpi) in NHNE cells, and IL-17C mRNA levels increased until 48 hpi. The PAO1 colonies significantly increased from 8 hpi in NHNE cells, and siderophore activity of PAO1 was enhanced in the supernatants of PAO1-infected NHNE cells. Interestingly, PAO1 colonies were reduced in PAO1-infected NHNE cells treated with rhIL-17C, and supernatants from NHNE cells treated with rhIL-17C also exhibited decreased PAO1 colonies. We found that the siderophore activity of PAO1 was significantly reduced in the supernatants of NHNE cells treated with rhIL-17C where LCN2 expression was highly elevated. Our findings indicate that IL-17C mediates an antibacterial effect against PAO1 by inhibiting siderophore activity in nasal epithelium. We propose that IL-17C might be an efficient mediator to suppress PAO1 infection through disturbing iron absorption of PAO1 in nasal epithelium.

Symbiotic microbiome Staphylococcus aureus from human nasal mucus modulates IL-33-mediated type 2 immune responses in allergic nasal mucosa.

BACKGROUND: The host-microbial commensalism can shape the innate immune responses in respiratory mucosa and nasal microbiome also modulates front-line immune mechanism in the nasal mucosa. Inhaled allergens encounter the host immune system first in the nasal mucosa, and microbial characteristics of nasal mucus directly impact the mechanisms of initial allergic responses in nasal epithelium. However, the roles of the nasal microbiome in allergic nasal mucosa remain uncertain. We sought to determine the distribution of nasal microbiomes in allergic nasal mucosa and elucidate the interplay between nasal microbiome Staphylococcus species and Th2 cytokines in allergic rhinitis (AR) models. RESULTS: Staphylococcus aureus (AR-SA) and S. epidermidis (AR-SE) were isolated from the nasal mucosa of patients with AR. The influence of nasal microbiome Staphylococcus species on allergic nasal mucosa was also tested with in vitro and in vivo AR models. Pyrosequencing data showed that colonization by S. epidermidis and S. aureus was more dominant in nasal mucus of AR subjects. The mRNA and protein levels of IL-33 and TSLP were significantly higher in AR nasal epithelial (ARNE) cells which were cultured from nasal mucosa of AR subjects, and exposure of ARNE cells to AR-SA reduced IL-33 mRNA and secreted protein levels. Particularly, ovalbumin-driven AR mice inoculated with AR-SA by intranasal delivery exhibited significantly reduced IL-33 in their nasal mucosa. In the context of these results, allergic symptoms and Th2 cytokine levels were significantly downregulated after intranasal inoculation of AR-SA in vivo AR mice. CONCLUSION: Colonization by Staphylococcus species was more dominant in allergic nasal mucosa, and nasal commensal S. aureus from subjects with AR mediates anti-allergic effects by modulating IL-33-dependent Th2 inflammation. The results demonstrate the role of host-bacterial commensalism in shaping human allergic inflammation.

Clinicopathological and Preclinical Findings of NUT Carcinoma: A Multicenter Study.

BACKGROUND: NUT carcinoma is a rare aggressive disease caused by BRD4/3-NUT fusion, and C-MYC upregulation plays a key role in the pathogenesis. Here, we report on the clinicopathological characteristics of Korean patients with NUT carcinoma and the in vitro efficacy of MYC-targeting agents against patient-derived NUT carcinoma cell lines. MATERIALS AND METHODS: Thirteen patients with NUT carcinoma were evaluated for p53, C-MYC, epidermal growth factor receptor (EGFR), HER2, and programmed cell death ligand 1 (PD-L1) by immunohistochemistry. The half maximal inhibitory concentration (IC50) values of NUT carcinoma cell lines (SNU-2972-1, SNU-3178S, HCC2429, and Ty-82) were determined using MYC-targeting agents, including bromodomain and extraterminal (BET) inhibitors (I-BET, OTX-015, AZD5153) and histone deacetylase (HDAC) inhibitors (vorinostat, romidepsin, panobinostat, CUDC-907). RESULTS: Primary tumor sites included head and neck (n = 9) and lung (n = 4). The patient age ranged from 8 to 73 years with the male/female ratio of 1.2:1. Nine patients died at 3-23.6 months (median, 10.6) after diagnosis. Eight patients had been misdiagnosed initially with other diseases. One patient with metastatic NUT carcinoma who received mass excision plus metastasectomy followed by chemoradiotherapy was a long-term survivor (>27 months). Although expressions of C-MYC (8/12, 73%) and p53 (12/12, 100%) were commonly observed, EGFR, HER2, and PD-L1 expressions were observed in 2 of 7 (29%), 2 of 8 (25%), and 1 of 12 (8.3%) patients, respectively. BET and HDAC inhibitors showed variable but limited in vitro efficacy. However, a dual HDAC/PI3K inhibitor, CUDC-907, was most potent against NUT carcinoma cells, with an IC50 of 5.5-9.0 pmol/L. Consistent with these findings, kinome short interfering RNA screening showed a positive hit for PI3KCA in NUT carcinoma cells. Panobinostat (IC50, 0.4-1.3 nmol/L) and a bivalent BET inhibitor, AZD5153 (IC50, 3.7-8.2 nmol/L), also showed remarkable efficacies. CONCLUSION: East Asian patients with NUT carcinoma showed dismal survival outcomes like Western patients, and CUDC-907 might be promising in NUT carcinoma treatment. IMPLICATIONS FOR PRACTICE: NUT carcinoma (NC) is a disease caused by BRD-NUT fusion leading to C-MYC upregulation. NC is often misdiagnosed and very aggressive, requiring development of effective therapeutic strategy. This article presents the clinicopathological features of the largest series of NCs in East Asians and preclinical sensitivities to MYC-targeting agents in NC cell lines. Patients with NC had grave outcomes and poor response to treatment. Among MYC-targeting agents, including BET and HDAC inhibitors, CUDC-907 (a dual PI3K/HDAC inhibitor) was most effective against NC cells, followed by panobinostat (an HDAC inhibitor) and AZD5153 (a bivalent BET inhibitor). CUDC-907 might be promising in NC treatment.

Inhaled delivery of Interferon-lambda restricts epithelial-derived Th2 inflammation in allergic asthma.

The possibility has been suggested that interferon (IFN)-λs can be induced rapidly for restricting respiratory viral infection in asthmatic mice and may modulate Th2-related immune responses that underlie the pathogenesis of asthma. We sought to determine the in vivo contribution of IFN-λs on decrease of Th2 cytokines in the respiratory tract of in vivo asthma. Lungs of asthmatic mice were severely inflamed, with extensive inflammatory cell infiltration and increased goblet cell metaplasia with higher total lung resistance. The mean protein levels of TSLP and IL-33 from BAL fluid of asthmatic mice were significantly higher until 7 days. Following the collection of lung tissue of 20 asthmatic mice, TSLP and IL-33 gene expressions inversely correlated with mRNA levels of IFN-λ2/3. Asthmatic mice were administered recombinant IFN-λ2/3 via the intranasal route and the mRNA levels of IFN-stimulated genes were elevated to an even greater extent in the lung tissue of the mice without intranasal IFN-λ2/3. Asthma-related histopathologic lung inflammation was significantly improved and total lung resistance was maintained within normal range in IFN-λ2/3-treated asthmatic mice. Moreover, IFN-λ2/3-treated asthmatic mice exhibited significant decrease of secreted protein levels of TSLP and IL-33 in the BAL fluid until 7 days after IFN administration. The current data provide compelling evidence that the compensation of IFN-λs can restrict the secretion of epithelial-derived Th2 cytokines, accompanied with reduced asthmatic immunopathology and IFN-λs are critical for limiting Th2-mediated allergic responses in allergic asthma.

The association between obstructive sleep apnea during REM sleep and autonomic dysfunction as measured by heart rate variability.

PURPOSE: To determine the effect of obstructive sleep apnea (OSA) during rapid eye movement (REM) sleep on autonomic dysfunction using heart rate variability (HRV) analysis. METHODS: The medical records of adults who underwent nocturnal polysomnography at the Sleep and Chronobiology Center at Seoul National University Hospital were retrospectively reviewed. HRV parameters (mean RR interval, the standard deviation of all normal RR intervals [SDNN], square root of the mean squared differences of adjacent RR intervals [RMSSD], normalized low frequency [LF], normalized high frequency [HF], and the ratio of LF to HF [LF/HF]) were measured in 5-min electrocardiogram recordings obtained during W, N2, and R sleep stages. Comparisons were made among the control (apnea-hypopnea index (AHI < 15 and AHI during REM sleep (AHIREM) < 15, n = 27), REM-associated OSA (AHI < 15 and AHIREM ≥ 15, n = 27), and OSA (AHI ≥ 15, n = 27) groups. The groups were matched for age, sex, and body mass index. RESULTS: No significant differences were observed between the control and the REM-associated OSA groups for any of the HRV parameters. In contrast, compared with controls, the OSA group showed significantly lower normalized HF (p = 0.031) and higher LF/HF (p = 0.018) in stage W and a significantly shorter mean RR interval (p = 0.046) and lower RMSSD (p = 0.034) in stage N2. CONCLUSIONS: Our findings suggest that OSA during REM sleep is not a major contributor to autonomic dysfunction.

Acute invasive fungal rhinosinusitis: MR imaging features and their impact on prognosis.

PURPOSE: Acute invasive fungal rhinosinusitis (AIFRS) is a life-threatening disease that is difficult to diagnose. Its overall imaging features have not been evaluated and the prognostic impact is unclear. The purpose of our study was to present MR imaging features and their impact on prognosis of AIFRS. METHODS: MR images and clinical records of 23 patients with AIFRS were retrospectively evaluated to identify the imaging features and to determine the factors affecting patients' survival. A multivariable Cox proportional hazard model was used to estimate the hazard ratio of the prognostic factors, and Kaplan-Meier survival curves were compared by using a log-rank test. RESULTS: All cases showed extra-sinonasal involvement and the orbit was the most common (65.2%, 15/23) location. The lesion enhancement pattern was classified into lack of contrast enhancement (LoCE) (47.8%, 11/23) and homogeneous (34.8%, 8/23) and heterogeneous (17.4%, 4/23) enhancement. Although LoCE showed variable signal intensity (SI), homogeneously or heterogeneously enhancing lesions showed exclusively low SI (100%, 12/12) on T2WI. Among various clinical and imaging factors, LoCE was correlated with coagulation necrosis, probably provoked by numerous fungal hyphae, and was found to be a sole independent prognostic factor for disease-specific mortality (hazard ratio = 16.819; 95% CI, 1.646-171.841, p = 0.017). In addition, patients with LoCE showed worse survival than patients without LoCE (p = 0.008). CONCLUSION: AIFRS showed frequent extra-sinonasal involvement and variable MR enhancement patterns. An enhancement pattern of LoCE was seen in about half of the cases and was a unique prognostic factor among the various clinico-radiologic factors.

Duox2-induced innate immune responses in the respiratory epithelium and intranasal delivery of Duox2 DNA using polymer that mediates immunization.

Respiratory mucosa especially nasal epithelium is well known as the first-line barrier of air-borne pathogens. High levels of reactive oxygen species (ROS) are detected in in vitro cultured human epithelial cells and in vivo lung. With identification of NADPH oxidase (Nox) system of respiratory epithelium, the antimicrobial role of ROS has been studied. Duox2 is the most abundant Nox isoform and produces the regulated amount of ROS in respiratory epithelium. Duox2-derived ROS are involved in antiviral innate immune responses but more studies are needed to verify the mechanism. In respiratory epithelium, Duox2-derived ROS is critical for recognition of virus through families retinoic acid-inducible gene-I (RIG-I) and melanoma differentiation-associated protein 5 (MDA5) at the early stage of antiviral innate immune responses. Various secreted interferons (IFNs) play essential roles for antiviral host defense by downstream cell signaling, and transcription of IFN-stimulated genes is started to suppress viral replication. Type I and type III IFNs are verified more responsible for influenza A virus (IAV) infection in respiratory epithelium and Duox2 is required to regulate IFN-related immune responses. Transient overexpression of Duox2 using cationic polymer polyethylenimine (PEI) induces secretion of type I and type III IFNs and significantly attenuated IAV replication in respiratory epithelium. Here, we discuss Duox2-mediated antiviral innate immune responses and the role of Duox2 as a mucosal vaccine to resist respiratory viral infection.

Intranasal delivery of Duox2 DNA using cationic polymer can prevent acute influenza A viral infection in vivo lung.

We studied the contribution of Duox2 in mucosal host defense against influenza A virus (IAV) infection in in vivo lung. We found that Duox2 was required for the induction of type I and III interferon (IFN)s and transient Duox2 overexpression using cationic polymer polyethyleneimine (PEI) leads to suppression of IAV infection in in vivo lung. Twenty mice (C57BL/6J) were anesthetized and challenged by intranasal administration of 213 pfu/30 µl of IAV (WS/33/H1N1), and IAV-infected mice were euthanized at 1, 3, 5, 7, 10, 14 days post infection (dpi). Duox2 small hairpin RNA (shRNA) and pCMV-Duox2 formulated with PEI were inoculated to mice to assess the regulatory mechanism between Duox2 and IFN secretion. Following intranasal IAV inoculation, viral infection was significantly aggravated from 3 dpi in in vivo lung and viral titer was highest at 7 dpi. Consistent with this, Duox2 messenger RNA (mRNA) and protein expressions were significantly induced from 3 dpi in the lung tissue of IAV-infected mice. Viral titer was much higher in IAV-infected mice that were inoculated with Duox2 shRNA accompanied with lower survival rate and extensive lung pathologies. Interestingly, severe lung pathologies in IAV-infected mice were not observed and viral titer was significantly reduced in mice with pulmonary administration of pCMV-Duox2 formulated with PEI before IAV inoculation. Both mRNA and secreted protein levels of IFN-ß and IFN-λ2/3 were highly elevated in IAV-infected mice with pCMV-Duox2 formulated with PEI. Duox2 is necessary for the regulation of IFN secretion in in vivo lung, and pulmonary administration of Duox2 DNA using cationic polymer triggers the induction of type I and III IFNs resulting in more complete suppression of IAV infection.

The Superiority of IFN-λ as a Therapeutic Candidate to Control Acute Influenza Viral Lung Infection.

Here, we studied the IFN-regulated innate immune response against influenza A virus (IAV) infection in the mouse lung and the therapeutic effect of IFN-λ2/3 in acute IAV lung infection. For viral infections, IAV (WS/33, H1N1, PR8 H1N1, H5N1) were inoculated into wild-type mice by intranasal delivery, and IAV mRNA level and viral titer were measured. To compare the antiviral effect of IFNs in vivo in the lung, neutralizing antibodies and recombinant IFNs were used. After intranasal inoculation of IAV into mice, viral infection peaked at 7 days postinfection, and the IAV titer also reached its peak at this time. We found that IFN-ß and IFN-λ2/3 were preferentially induced after IAV infection and the IFN-λ2/3-mediated innate immune response was specifically required for the induction of IFN-stimulated genes (ISGs) transcription in the mouse respiratory tract. Neutralization of secreted IFN-λ2/3 aggravated acute IAV lung infection in mice with intact IFN-ß induction; consistent with this finding, the transcription of ISGs was significantly reduced. Intranasal administration of IFN-λ2/3 significantly suppressed various strains of IAV infection, including WS/33 (H1N1), PR (H1N1), and H5N1 in the mouse lung, and was accompanied by greater up-regulation of ISGs. Taken together, our data indicate that the IFN-λ2/3-mediated innate immune response is necessary to protect the lungs from IAV infection, and intranasally delivered IFN-λ2/3 has the potential to be a useful therapeutic strategy for treating acute IAV lung infection.