Immunomodulatory effect of PLGA-encapsulated mesenchymal stem cells-derived exosomes for the treatment of allergic rhinitis.

Introduction: Allergic rhinitis (AR) is an upper airway inflammatory disease of the nasal mucosa. Conventional treatments such as symptomatic pharmacotherapy and allergen-specific immunotherapy have considerable limitations and drawbacks. As an emerging therapy with regenerative potential and immunomodulatory effect, mesenchymal stem cell-derived exosomes (MSC-Exos) have recently been trialed for the treatment of various inflammatory and autoimmune diseases. Methods: In order to achieve sustained and protected release of MSC-Exos for intranasal administration, we fabricated Poly(lactic-co-glycolic acid) (PLGA) micro and nanoparticles-encapsulated MSC-Exos (PLGA-Exos) using mechanical double emulsion for local treatment of AR. Preclinical in vivo imaging, ELISA, qPCR, flow cytometry, immunohistochemical staining, and multiomics sequencing were used for phenotypic and mechanistic evaluation of the therapeutic effect of PLGA-Exos in vitro and in vivo. Results: The results showed that our PLGA platform could efficiently encapsulate and release the exosomes in a sustained manner. At protein level, PLGA-Exos treatment upregulated IL-2, IL-10 and IFN-γ, and downregulated IL-4, IL-17 and antigen-specific IgE in ovalbumin (OVA)-induced AR mice. At cellular level, exosomes treatment reduced Th2 cells, increased Tregs, and reestablished Th1/Th2 balance. At tissue level, PLGA-Exos significantly attenuated the infiltration of immune cells (e.g., eosinophils and goblet cells) in nasal mucosa. Finally, multiomics analysis discovered several signaling cascades, e.g., peroxisome proliferator-activated receptor (PPAR) pathway and glycolysis pathway, that might mechanistically support the immunomodulatory effect of PLGA-Exos. Discussion: For the first time, we present a biomaterial-facilitated local delivery system for stem cell-derived exosomes as a novel and promising strategy for AR treatment.

Tolerance to Haemophilus influenzae infection in human epithelial cells: Insights from a primary cell-based model.

Haemophilus influenzae is a human respiratory pathogen and inhabits the human respiratory tract as its only niche. Despite this, the molecular mechanisms that allow H. influenzae to establish persistent infections of human epithelia are not well understood. Here, we have investigated how H. influenzae adapts to the host environment and triggers the host immune response using a human primary cell-based infection model that closely resembles human nasal epithelia (NHNE). Physiological assays combined with dualRNAseq revealed that NHNE from five healthy donors all responded to H. influenzae infection with an initial, 'unproductive' inflammatory response that included a strong hypoxia signature but did not produce pro-inflammatory cytokines. Subsequently, an apparent tolerance to large extracellular and intraepithelial burdens of H. influenzae developed, with NHNE transcriptional profiles resembling the pre-infection state. This occurred in parallel with the development of intraepithelial bacterial populations, and appears to involve interruption of NFκB signalling. This is the first time that large-scale, persistence-promoting immunomodulatory effects of H. influenzae during infection have been observed, and we were able to demonstrate that only infections with live, but not heat-killed H. influenzae led to immunomodulation and reduced expression of NFκB-controlled cytokines such as IL-1ß, IL-36γ and TNFα. Interestingly, NHNE were able to re-activate pro-inflammatory responses towards the end of the 14-day infection, resulting in release of IL-8 and TNFα. In addition to providing first molecular insights into mechanisms enabling persistence of H. influenzae in the host, our data further indicate the presence of infection stage-specific gene expression modules, highlighting fundamental similarities between immune responses in NHNE and canonical immune cells, which merit further investigation.

m6A mRNA methylation-mediated MAPK signaling modulates the nasal mucosa inflammatory response in allergic rhinitis.

Background: Allergic rhinitis (AR) is a complex disease in which gene-environment interactions contribute to its pathogenesis. Epigenetic modifications, such as N6-methyladenosine (m6A) modification of mRNA, play important roles in regulating gene expression in multiple physiological and pathological processes. However, the function of m6A modification in AR and the inflammatory response is poorly understood. Methods: We used the ovalbumin (OVA) and aluminum hydroxide to induce an AR mouse model. Nasal symptoms, histopathology, and serum cytokines were examined. We performed combined m6A and RNA sequencing to analyze changes in m6A modification profiles. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and methylated RNA immunoprecipitation sequencing qPCR (MeRIP-qPCR) were used to verify differential methylation of mRNAs and the m6A methylation level. Knockdown or inhibition of Alkbh5 in nasal mucosa of mice was mediated by lentiviral infection or IOX1 treatment. Results: We showed that m6A was enriched in a group of genes involved in MAPK signaling pathway. Moreover, we identified a MAPK pathway involving Map3k8, Erk2, and Nfκb1 that may play a role in the disrupted inflammatory response associated with nasal inflammation. The m6A eraser, Alkbh5, was highly expressed in the nasal mucosa of AR model mice. Furthermore, knockdown of Alkbh5 expression by lentiviral infection resulted in high MAPK pathway activity and a significant nasal mucosa inflammatory response. Our findings indicate that ALKBH5-mediated m6A dysregulation likely contributes to a nasal inflammatory response via the MAPK pathway. Conclusion: Together, our data show that m6A dysregulation mediated by ALKBH5, is likely to contribute to inflammation of the nasal mucosa via the MAPK signaling pathway, suggesting that ALKBH5 is a potential biomarker for AR treatment.

Rat nasal mucosa-derived ectodermal mesenchymal stem cells: A new therapeutic option for chronic rhinosinusitis.

OBJECTIVE: To investigate the effect of nasal mucosa-derived ectodermal mesenchymal stem cells (NM-EMSCs) on the inflammatory state of rats with chronic rhinosinusitis (CRS) and the underlying therapeutic mechanism. METHODS: NM-EMSCs were isolated and extracted to construct a rat model of CRS. Fifteen Sprague‒Dawley (SD) rats were randomly divided into three groups: CK + NS group rats were injected locally with saline in the nasal mucosa; CRS + NS group rats were injected locally with saline in the nasal mucosa; and CRS + EMSCs group rats were injected locally with NM-EMSCs in the nasal mucosa. One rat from the CRS + EMSCs group was randomly euthanized at 2, 4, and 6 days after injection, and the nasal mucosa tissues were collected for HE staining, Masson's trichrome staining, and periodic acid-Schiff staining. RESULTS: NM-EMSCs specifically expressing CD73, CD105, and CD90 were successfully isolated from the nasal mucosa of rats and were able to differentiate into adipocytes, osteoblasts, and chondrocytes. After saline and NM-EMSC injection, compared with those in the blank control CK + NS group, the nasal mucosa in the CRS + NS and CRS + EMSC groups exhibited obvious thickening, a large amount of inflammatory cell infiltration, and increased collagen and mucin distribution. Four days post-NM-EMSC injection, the thickening of the nasal mucosa in the CRS group was gradually alleviated, the inflammatory cell infiltration gradually decreased, and the distribution of collagen and mucin and the collagen-positive area gradually decreased. Moreover, only a small number of inflammatory cells were visible, and the distribution of mucins was limited to 6 days post-NM-EMSC injection. CONCLUSION: NM-EMSCs effectively attenuated inflammation in the nasal mucosa of CRS model rats.

[Characterizing immune microenvironment cell composition of chronic rhinosinusitis with nasal polyps based on mass cytometry technology].

Objective: To analyze the cellular composition characteristics of the nasal tissue immune microenvironment in patients with control, chronic rhinosinusitis without nasal polyps (CRSsNP), non-eosinophilic chronic rhinosinusitis with nasal polyps (neCRSwNP), and eosinophilic chronic rhinosinusitis with nasal polyps (eCRSwNP) using mass cytometry flow technology. Methods: Thirteen CRS patients who underwent endoscopic nasal surgery at the Department of Otorhinolaryngology Head and Neck Surgery of Peking Union Medical College Hospital from March to December 2022 were recruited, including 8 males and 5 females, aged 22.3 to 58.3 years. Three control mucosae were obtained from normal ethmoid or sphenoid sinuses of patients with benign tumors of the temporal fossa or non-functional pituitary adenomas who underwent endoscopic surgery, excluding allergic rhinitis and sinusitis. Sixteen clinical tissue samples (3 of control, 3 of CRSsNP, 4 of neCRSwNP, and 6 of eCRSwNP) were prepared into single-cell suspensions. Mass cytometry flow detection was performed using a combination of 42 molecular markers to analyze the differences in cell subpopulations among the groups. Data were analyzed using GraphPad Prism 9. Results: Based on the mass cytometry flow results, cells from control, CRSsNP, neCRSwNP, and eCRSwNP were divided into seven main cell subgroups, with detailed subgrouping of T/NK cells and myeloid cells. In T/NK cells, compared with the control group, the number of NK CD56bright cells increased in the CRSsNP group, while NK CD56dim cells decreased; compared with the CRSsNP group, the eCRSwNP group showed a decrease in NKT cells and CD4+Tem cells; compared with the CRSsNP group, the eCRSwNP group showed a significant increase in CD25 expression within Treg cells; compared with the CRSsNP group, the eCRSwNP group showed a significant decrease in Tbet expression in CD8+Teff cells and CD8+TRM cells; in eCRSwNP, the expression of CD103 in CD8+TRM cells was significantly lower than in CRSsNP. In myeloid cells, compared with the other three groups, the eCRSwNP group showed a significant increase in macrophages and a significant decrease in cDC1 and monocytes; compared with the control group and CRSsNP, the eCRSwNP group also showed a significant decrease in resting state macrophages; compared with the CRSsNP group, the eCRSwNP group showed a significant decrease in the level of CX3CR1 within cDC2 and monocytes; the expression levels of NLRP3 in cDC2 and macrophages in the eCRSwNP group were significantly higher than in the other three groups; compared with the control group, the expression levels of Gata3 in cDC2 and macrophages in the eCRSwNP group were also significantly increased; additionally, the expression of CCR2 within monocytes in the eCRSwNP group was lower than in the CRSsNP group. In ILC, compared with the control group, the expression of CCR6 decreased in the eCRSwNP group. Conclusions: Compared with the control group, CRSsNP, and neCRSwNP, eCRSwNP shows an increase in macrophage number, a decrease in cDC1 and resting state macrophages, and depletion of protective cells CD103+CD8+TRM. Additionally, the expression levels of CCR2 and CX3CR1 in monocytes of eCRSwNP are decreased.

[Effects of PM2.5 and O3 sub-chronic combined exposure on ATP amount and ATPase activities in rat nasal mucosa].

OBJECTIVE: To evaluate the effects of fine particle matter (PM2.5) and ozone (O3) combined exposure on adenosine triphosphate (ATP) amount and ATPase activities in nasal mucosa of Sprague Dawley (SD) rats. METHODS: Twenty male SD rats were divided into control group (n=10) and exposure group (n=10) by random number table method. The rats were fed in the conventional clean environment and the air pollutant exposure system established by our team, respectively, and exposed for 208 d. During the exposure period, the concentrations of PM2.5 and O3 in the exposure system were monitored, and a comprehensive assessment of PM2.5 and O3 in the exposure system was conducted by combining self-measurement and site data. On the 208 d of exposure, the core, liver, spleen, kidney, testis and other major organs and nasal mucosal tissues of the rats were harvested. Each organ was weighed and the organ coefficient calculated. The total amount of ATP was measured by bioluminescence, and the activities of Na+-K+ -ATPase and Ca2+ -ATPase were detected by spectrophotometry. The t test of two independent samples was used to compare the differences among the indicator groups. RESULTS: From the 3rd week to the end of exposure duration, the body weight of the rats in the exposure group was higher than that in the control group (P < 0.05), and there was no significant difference in organ coefficients between the two groups. The average daily PM2.5 concentration in the exposure group was (30.68±19.23) µg/m3, and the maximum 8 h ozone concentration (O3-8 h) was (82.45±35.81) µg/m3. The chemiluminescence value (792.4±274.1) IU/L of ATP in nasal mucosa of the rats in the exposure group was lower than that in the control group (1 126.8±218.1) IU/L. The Na+-K+-ATPase activity (1.53±0.85) U/mg in nasal mucosa of the rats in the exposure group was lower than that in the control group (4.31±1.60) U/mg (P < 0.05). The protein content of nasal mucosa in the control group and the exposure group were (302.14±52.51) mg/L and (234.58±53.49) mg/L, respectively, and the activity of Ca2+-ATPase was (0.81±0.27) U/mg and (0.99±0.73) U/mg, respectively. There was no significant difference between the groups. CONCLUSION: The ability of power capacity decreased in the rat nasal mucossa under the sub-chronic low-concentration exposure of PM2.5 and O3.

Nicotiana benthamiana-derived dupilumab-scFv reaches deep into the cultured human nasal epithelial cells and inhibits CCL26 expression.

Plants offer a cost-effective and scalable pharmaceutical platform devoid of host-derived contamination risks. However, their medical application is complicated by the potential for acute allergic reactions to external proteins. Developing plant-based protein therapeutics for localized diseases with non-invasive treatment modalities may capitalize on the benefits of plant proteins while avoiding their inherent risks. Dupilumab, which is effective against a variety of allergic and autoimmune diseases but has systemic responses and injection-related side effects, may be more beneficial if delivered locally using a small biological form. In this study, we engineered a single-chain variable fragment (scFv) of dupilumab, termed Dup-scFv produced by Nicotiana benthamiana, and evaluated its tissue permeability and anti-inflammatory efficacy in air-liquid interface cultured human nasal epithelial cells (HNECs). Despite showing 3.67- and 17-fold lower binding affinity for IL-4Ra in surface plasmon resonance assays and cell binding assays, respectively, Dup-scFv retained most of the affinity of dupilumab, which was originally high, with a dissociation constant (KD) of 4.76 pM. In HNECs cultured at the air-liquid interface, Dup-scFv administered on the air side inhibited the inflammatory marker CCL26 in hard-to-reach basal cells more effectively than dupilumab. In addition, Dup-scFv had an overall permeability of 0.8% across cell layers compared to undetectable levels of dupilumab. These findings suggest that plant-produced Dup-scFv can be delivered non-invasively to cultured HNESc to alleviate inflammatory signaling, providing a practical approach to utilize plant-based proteins for topical therapeutic applications.

Modeling brain pathology to study nose-to-brain drug delivery.

OBJECTIVES: To create a new mucoadhesive dosage form based on PluronicF127 followed by transformation into a gel form upon intranasal administration for targeted delivery to brain tissueMETHODS: Citicoline, cytidine diphosphocholine, designated as CDP-choline, was purchased as a white powder with the molecular weight of 510.31 g/mol. The triblock copolymers of polyethylene glycol-block-polypropylene glycol-block-polyethylene glycol (PEG-PPG-PEG), branded as Pluronic F127, was used. RESULTS: When instilled into the nasal cavity, Pluronic F127 for intranasal administration is transformed into a gel that remains retained for 45-55 minutes, which promotes better penetration of drugs into the brain tissue. CONCLUSION: The polymer's gelling and adhesive properties performed well, which is crucial for further research at the preclinical stage (Tab. 1, Fig. 5, Ref. 28).

Safety evaluation of adenosine, lidocaine and magnesium (ALM) intranasal therapy toward human nasal epithelial cells in vitro.

Adenosine, lidocaine and Mg2+ (ALM) solution is an emerging therapy that reduces secondary injury after intravenous administration in experimental models of traumatic brain injury (TBI). Intranasal delivery of ALM may offer an alternative route for rapid, point-of-care management of TBI. As a preliminary safety screen, we evaluated whether ALM exerts cytotoxic or inflammatory effects on primary human nasal epithelial cells (pHNEC) in vitro. Submerged monolayers and air-liquid interface cultures of pHNEC were exposed to media only, normal saline only, therapeutic ALM or supratherapeutic ALM for 15 or 60 min. Safety was measured through viability, cytotoxicity, apoptosis, cellular and mitochondrial stress, and inflammatory mediator secretion assays. No differences were found in viability or cytotoxicity in cultures exposed to saline or ALM for up to 60 min, with no evidence of apoptosis after exposure to supratherapeutic ALM concentrations. Despite comparable inflammatory cytokine secretion profiles and mitochondrial activity, cellular stress responses were significantly lower in cultures exposed to ALM than saline. In summary, data show ALM therapy has neither adverse toxic nor inflammatory effects on human nasal epithelial cells, setting the stage for in vivo toxicity studies and possible clinical translation of intranasal ALM therapy for TBI treatment.

Interferon signaling in the nasal epithelium distinguishes among lethal and common cold coronaviruses and mediates viral clearance.

All respiratory viruses establish primary infections in the nasal epithelium, where efficient innate immune induction may prevent dissemination to the lower airway and thus minimize pathogenesis. Human coronaviruses (HCoVs) cause a range of pathologies, but the host and viral determinants of disease during common cold versus lethal HCoV infections are poorly understood. We model the initial site of infection using primary nasal epithelial cells cultured at an air-liquid interface (ALI). HCoV-229E, HCoV-NL63, and human rhinovirus-16 are common cold-associated viruses that exhibit unique features in this model: early induction of antiviral interferon (IFN) signaling, IFN-mediated viral clearance, and preferential replication at nasal airway temperature (33 °C) which confers muted host IFN responses. In contrast, lethal SARS-CoV-2 and MERS-CoV encode antagonist proteins that prevent IFN-mediated clearance in nasal cultures. Our study identifies features shared among common cold-associated viruses, highlighting nasal innate immune responses as predictive of infection outcomes and nasally directed IFNs as potential therapeutics.

[H3K27 acetylation promotes lncRNA OIP5-AS1 transcription and induces apoptosis of nasal epithelial cells in allergic rhinitis through up-regulation of TLR4].

Objective To investigate the effect of lysine 27 residue of histone H3 (H3K27) acetylation modification on the transcriptional promotion of long noncoding RNA OPA interacting protein 5-antisense RNA 1 (lncRNA OIP5-AS1) and apoptosis of nasal epithelial cells (NECs) in allergic rhinitis (AR) via regulating Toll-like receptor 4 (TLR4). Methods Interleukin-13 (IL-13) was used to treat NECs to establish an AR cell model. Real-time quantitative PCR was utilized to detect the expressions of OIP5-AS1 and TLR4 in nasal mucosal tissues of AR patients and in the in vitro cell model. The concentrations of macrophage colony-stimulating factor (GM-CSF), eotaxin-1, and mucin 5AC (MUC5AC) were detected by ELISA. The apoptosis of NECs was determined by terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL). A dual-luciferase report experiment was carried out to verify the relationship between OIP5-AS1 and TLR4. Chromatin immunoprecipitation (ChIP) assay was performed to verify H3K27 acetylation of histones in the OIP5-AS1 promoter region. Results Compared with healthy controls and untreated NECs, OIP5-AS1 and TLR4 were both up-regulated in nasal mucosal tissues from AR patients and IL-13-stimulated NECs. Knockdown of OIP5-AS1 decreased the level of TLR4 in IL-13-treated NECs, while overexpression of OIP5-AS1 increased the level of TLR4. Inhibition of OIP5-AS1 reduced the apoptosis rate, and inhibited the secretion of GM-CSF, eotaxin-1, and MUC5AC from IL-13-treated NECs, while overexpression of TLR4 partially reversed the effects of OIP5-AS1 knockdown on NEC apoptosis and the secretion of GM-CSF, eotaxin-1, and MUC5AC. In addition, H3K27 acetylation was markedly enriched in the promoter region of OIP5-AS1, and H3K27 acetylation promoted the expression of OIP5-AS1 in IL-13-treated NECs. Conclusion H3K27 acetylation promotes OIP5-AS1 transcription and induces NEC apoptosis in AR via upregulation of TLR4.

Nasal mucosal fibroblasts produce IL-4 to induce Th2 response.

Th2 polarization is essential for the pathogenesis of allergic rhinitis (AR). Th2 polarization's mechanism requires further understanding. IL-4 is the primary cytokine involved in Th2 response. Fibroblasts play a role in immune regulation. This study aims to elucidate the role of nasal mucosal fibroblast-derived IL-4 in the induction of Th2 responses. Nasal mucosal tissues were obtained from surgically removed samples from patients with nasal polyps, whether with or without AR. Fibroblasts were isolated from the tissues by flow cytometry cell sorting, and analyzed by RNA sequencing (RNAseq). The data from RNAseq showed that nasal fibroblasts expressed genes of GATA3, CD80, CD83, CD86, STAT6, IL2, IL4, IL5, IL6, IL13 and costimulatory factor. The data were verified by RT-qPCR. The level of gene activity was positively correlated with those of AR-related cytokines present in nasal secretions. Nasal fibroblasts release IL-4 upon activation. Nasal fibroblasts had the ability to transform naive CD4+ T cells into Th2 cells, which can be eliminated by inhibiting IL-4 receptor or CD28 in CD4+ T cells. To sum up, nasal mucosal fibroblasts produce IL-4, which can induce Th2 cell development. The data implicate that nasal fibroblasts are involved in the pathogenesis of nasal allergy.

Association of mucus eosinophil-derived neurotoxin levels with disease control status in patients with chronic rhinosinusitis.

OBJECTIVE: Identifying the biomarkers for uncontrolled chronic rhinosinusitis (CRS) is important for directing treatment decisions. Eosinophilia has been reported to be involved in the poor disease control of CRS and mucus eosinophil-derived neurotoxin (EDN) is potentially a biomarker of intense eosinophil activation. This study aimed to assess the relationship between mucus EDN levels, disease severity, and degree of CRS control. METHODS: A total of 150 adult patients with CRS and 25 healthy controls were prospectively enrolled. The nasal mucus and tissue specimens were collected to analyze EDN levels. Disease severity was assessed by Lund-Mackay score and 22-item Sino-Nasal Outcome Test (SNOT-22) score. Five CRS symptom severities during the prior month (nasal blockage, rhinorrhoea/postnasal drip, facial pain/pressure, smell, sleep disturbance or fatigue), use of rescue medications in the last six months, and the presence of diseased mucosa on nasal endoscopy were obtained. Consistent with the European Position Paper on Rhinosinusitis and Nasal Polyps 2020 CRS control criteria, uncontrolled CRS was defined as meeting at least three items. RESULTS: 40% of patients with CRS presented with uncontrolled status. Patients with uncontrolled CRS had significantly higher nasal mucus EDN levels (P = 0.010), percentage of blood eosinophil (P = 0.015), SNOT-22 score (P < 0.001), Lund-Mackay score (P = 0.008), and a more eosinophilic dominant phenotype of CRS (P < 0.001) than patients with controlled CRS. Furthermore, mucus EDN levels were positively correlated with blood eosinophils (r = 0.541, P = 0.005), SNOT-22 score (r = 0.460, P = 0.021), and Lund-Mackay score (r = 0.387, P = 0.039). Mucus EDN levels were the significant parameter related to uncontrolled CRS in multivariable analysis after adjusting for patient demographics and comorbidities (odds ratio = 1.323; P = 0.004). CONCLUSIONS: Mucus EDN levels may be a potential biomarker for identifying the CRS control status.

The oxidant-antioxidant imbalance was involved in the pathogenesis of chronic rhinosinusitis with nasal polyps.

Background: Although oxidative stress is involved in the pathophysiological process of chronic rhinosinusitis with nasal polyps (CRSwNP), the specific underlying mechanism is still unclear. Whether antioxidant therapy can treat CRSwNP needs further investigation. Methods: Immunohistochemistry, immunofluorescence, western blotting and quantitative polymerase chain reaction (qPCR) analyses were performed to detect the distribution and expression of oxidants and antioxidants in nasal polyp tissues. qPCR revealed correlations between oxidase, antioxidant enzymes and inflammatory cytokine levels in CRSwNP patients. Human nasal epithelial cells (HNEpCs) and primary macrophages were cultured to track the cellular origin of oxidative stress in nasal polyps(NPs) and to determine whether crocin can reduce cellular inflammation by increasing the cellular antioxidant capacity. Results: The expression of NOS2, NOX1, HO-1 and SOD2 was increased in nasal epithelial cells and macrophages derived from nasal polyp tissue. Oxidase levels were positively correlated with those of inflammatory cytokines (IL-5 and IL-6). Conversely, the levels of antioxidant enzymes were negatively correlated with those of IL-13 and IFN-γ. Crocin inhibited M1 and M2 macrophage polarization as well as the expression of NOS2 and NOX1 and improved the antioxidant capacity of M2 macrophages. Moreover, crocin enhanced the ability of antioxidants to reduce inflammation via the KEAP1/NRF2/HO-1 pathway in HNEpCs treated with SEB or LPS. Additionally, we observed the antioxidant and anti-inflammatory effects of crocin in nasal explants. Conclusion: Oxidative stress plays an important role in the development of CRSwNP by promoting various types of inflammation. The oxidative stress of nasal polyps comes from epithelial cells and macrophages. Antioxidant therapy may be a promising strategy for treating CRSwNP.

A common polymorphism in the Intelectin-1 gene influences mucus plugging in severe asthma.

By incompletely understood mechanisms, type 2 (T2) inflammation present in the airways of severe asthmatics drives the formation of pathologic mucus which leads to airway mucus plugging. Here we investigate the molecular role and clinical significance of intelectin-1 (ITLN-1) in the development of pathologic airway mucus in asthma. Through analyses of human airway epithelial cells we find that ITLN1 gene expression is highly induced by interleukin-13 (IL-13) in a subset of metaplastic MUC5AC+ mucus secretory cells, and that ITLN-1 protein is a secreted component of IL-13-induced mucus. Additionally, we find ITLN-1 protein binds the C-terminus of the MUC5AC mucin and that its deletion in airway epithelial cells partially reverses IL-13-induced mucostasis. Through analysis of nasal airway epithelial brushings, we find that ITLN1 is highly expressed in T2-high asthmatics, when compared to T2-low children. Furthermore, we demonstrate that both ITLN-1 gene expression and protein levels are significantly reduced by a common genetic variant that is associated with protection from the formation of mucus plugs in T2-high asthma. This work identifies an important biomarker and targetable pathways for the treatment of mucus obstruction in asthma.

The interleukin-4/interleukin-13 pathway in type 2 inflammation in chronic rhinosinusitis with nasal polyps.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is predominantly a type 2 inflammatory disease associated with type 2 (T2) cell responses and epithelial barrier, mucociliary, and olfactory dysfunction. The inflammatory cytokines interleukin (IL)-4, IL-13, and IL-5 are key mediators driving and perpetuating type 2 inflammation. The inflammatory responses driven by these cytokines include the recruitment and activation of eosinophils, basophils, mast cells, goblet cells, M2 macrophages, and B cells. The activation of these immune cells results in a range of pathologic effects including immunoglobulin E production, an increase in the number of smooth muscle cells within the nasal mucosa and a reduction in their contractility, increased deposition of fibrinogen, mucus hyperproduction, and local edema. The cytokine-driven structural changes include nasal polyp formation and nasal epithelial tissue remodeling, which perpetuate barrier dysfunction. Type 2 inflammation may also alter the availability or function of olfactory sensory neurons contributing to loss of sense of smell. Targeting these key cytokine pathways has emerged as an effective approach for the treatment of type 2 inflammatory airway diseases, and a number of biologic agents are now available or in development for CRSwNP. In this review, we provide an overview of the inflammatory pathways involved in CRSwNP and describe how targeting key drivers of type 2 inflammation is an effective therapeutic option for patients.

Occupational second-hand smoke exposure: A comparative shotgun proteomics study on nasal epithelia from healthy restaurant workers.

Non-smokers exposed to second-hand smoke (SHS) present risk of developing tobacco smoke-associated pathologies. To investigate the airway molecular response to SHS exposure that could be used in health risk assessment, comparative shotgun proteomics was performed on nasal epithelium from a group of healthy restaurant workers, non-smokers (never and former) exposed and not exposed to SHS in the workplace. HIF1α-glycolytic targets (GAPDH, TPI) and proteins related to xenobiotic metabolism, cell proliferation and differentiation leading to cancer (ADH1C, TUBB4B, EEF2) showed significant modulation in non-smokers exposed. In never smokers exposed, enrichment of glutathione metabolism pathway and EEF2-regulating protein synthesis in genotoxic response were increased, while in former smokers exposed, proteins (LYZ, ATP1A1, SERPINB3) associated with tissue damage/regeneration, apoptosis inhibition and inflammation that may lead to asthma, COPD or cancer, were upregulated. The identified proteins are potential response and susceptibility/risk biomarkers for SHS exposure.

Smoking-associated gene expression alterations in nasal epithelium reveal immune impairment linked to lung cancer risk.

BACKGROUND: Lung cancer is the leading cause of cancer-related death in the world. In contrast to many other cancers, a direct connection to modifiable lifestyle risk in the form of tobacco smoke has long been established. More than 50% of all smoking-related lung cancers occur in former smokers, 40% of which occur more than 15 years after smoking cessation. Despite extensive research, the molecular processes for persistent lung cancer risk remain unclear. We thus set out to examine whether risk stratification in the clinic and in the general population can be improved upon by the addition of genetic data and to explore the mechanisms of the persisting risk in former smokers. METHODS: We analysed transcriptomic data from accessible airway tissues of 487 subjects, including healthy volunteers and clinic patients of different smoking statuses. We developed a computational model to assess smoking-associated gene expression changes and their reversibility after smoking is stopped, comparing healthy subjects to clinic patients with and without lung cancer. RESULTS: We find persistent smoking-associated immune alterations to be a hallmark of the clinic patients. Integrating previous GWAS data using a transcriptional network approach, we demonstrate that the same immune- and interferon-related pathways are strongly enriched for genes linked to known genetic risk factors, demonstrating a causal relationship between immune alteration and lung cancer risk. Finally, we used accessible airway transcriptomic data to derive a non-invasive lung cancer risk classifier. CONCLUSIONS: Our results provide initial evidence for germline-mediated personalized smoke injury response and risk in the general population, with potential implications for managing long-term lung cancer incidence and mortality.

Chief Complaint: Nasal Congestion.

Nasal obstruction is the subjective perception and objective state of insufficient airflow through the nose. Nasal congestion, conversely, describes a state of not just inadequate airflow or obstructive phenomena but also pressure- and mucus-related states to the patient. Nasal receptors belonging to the transient receptor potential (TRP) protein family mediate the sense of nasal patency via the trigeminal nerve. The transient receptor potential melastatin-8 (TRPM8) responds to temperatures around 8°C to 22°C, and is stimulated by menthol and other cooling agents. The radiant effects of airflow create heat loss to activate these receptors and humans perceive this as nasal patency rather than the direct detection of airflow. The thermovascular state of the mucosa, in conditions such as rhinitis, influence TRPM8 activation. Nasal endoscopy can show signs of rhinitis and should be considered an essential part of the workup of nasal congestion. Efforts to relieve nasal congestion need to manage the mucosal state and surgery needs to ensures that the nasal cavity mucosa is exposed to the cooling effects of airflow rather than simply creating a passage to the nasopharynx.

[The auxiliary diagnostic value of ECP and MPO expression in nasal secretions in different types of rhinitis].

Objective:To evaluate the expression of eosinophil cationic protein and myeloperoxidase in nasal secretions in different types of rhinitis, and to explore their values in the differential diagnosis of different types of rhinitis. Methods:Six hundred and eighty-four subjects were selected, including 62 subjects in the acute rhinitis group, 378 subjects in the allergic rhinitis group, 94 subjects in the vasomotor rhinitis group, 70 subjects in the eosinophilic non-allergic rhinitis group, and 80 subjects in the control group. Nasal secretion samples were collected from the five groups, and the percentages of inflammatory cells were counted by Rachel's staining, and the expression of ECP/MPO was detected by colloidal gold assay. The correlation between the clinical diagnosis, the inflammatory cells in the nasal secretions and the expression of ECP/MPO was analyzed. Results:Nasal cytological smears showed that compared with the control group, the percentage of eosinophils in the AR and NARES groups were significantly higher （P<0.05）, while the percentage of neutrophils was not different （P>0.05）; the percentage of neutrophils was significantly higher in the acute rhinitis group compared with the control group （P<0.05）, while the percentage of eosinophils was not statistically different （P>0.05）; in vasomotor rhinitis group, the eosinophils and neutrophils were not statistically different compared with the control group（P> 0.05）. The colloidal gold results showed that there were differences in the expression of ECP/MPO in different types of rhinitis, among which 49 cases （79.0%） in the acute rhinitis group expressed ECP+/MPO+; 267 cases （70.6%） in the AR group and 56 cases （75.7%） in the NARES group expressed ECP+/MPO-; 80 cases （85.1%） in the vasomotor rhinitis group and 69 cases （86.3%） in the control group expressed ECP-/MPO-. Conclusion:The differences in ECP and MPO expression between different types of rhinitis have certain reference value for the differential diagnosis of different types of rhinitis and the selection of treatment programs.