ovalbumin and Nasal-Polyps

Eosinophilic chronic rhinosinusitis (ECRS) is predominantly characterized by nasal type 2 inflammation. The pathogenesis of this condition is complex. High levels of IL-17A are associated with eosinophil infiltration in some inflammatory diseases and contribute to the severity and insensitivity of corticosteroid therapy for chronic rhinosinusitis.. In the first experiment, we constructed a modified ECRS mouse model using four groups of mice: phosphate-buffered saline (PBS)-sensitized and nasal instillation (control); PBS-sensitized and Staphylococcus aureus enterotoxin B (SEB) nasal instillation after nasal tamponade (SEB group); ovalbumin (OVA)-sensitized and nasal instillation (OVA group); and OVA-sensitized combined with OVA and SEB nasal instillation after nasal tamponade (OVA + SEB group). In the second experiment, we examined the role of IL-17A by dividing the mice into four groups: control group; ECRS group; ECRS + anti-IL-17A group; and ECRS + IL-17A group. The latter two groups received intraperitoneal injections of anti-IL-17A antibody or IL-17A, respectively.. We constructed a modified ECRS mouse model (OVA + SEB group), where the IL-17A levels were upregulated in the nasal sinus of ECRS mice and the IL-17A levels were significantly correlated with eosinophil infiltration. We further demonstrated that IL-17A induced type 2 inflammation and eosinophil infiltration in the ECRS group of mice. In contrast, IL-17A neutralization attenuated type 2 inflammatory cytokine secretion and eosinophil infiltration.. OVA sensitization and unilateral nasal tamponade, combined with SEB and OVA alternate nasal instillation (OVA + SEB group), could be used to construct a more typical ECRS mouse model in which IL-17A enhanced the expression of type 2 cytokines and eosinophil infiltration.

Topics: Animals; Chronic Disease; Cytokines; Eosinophilia; Eosinophils; Inflammation; Mice; Nasal Polyps; Ovalbumin; Rhinitis; Sinusitis

Several factors, including bacterial and viral infections, have been associated with rhinosinusitis and nasal tissue remodelling that may result in nasal polyp formation. However, the potential role of bacterial or viral stimuli triggering polyp development is unclear. Here, we used lipopolysaccharide (LPS) and polyinosinic:polycytidylic acid [poly(I:C)] in a murine model of allergic rhinosinusitis to compare different effects of bacterial- and virus-derived stimuli in the pathogenesis of nasal polyp formation. Briefly, BALB/c mice were sensitised and challenged with ovalbumin and staphylococcal enterotoxin, with or without LPS or poly(I:C), and the consequent histopathological profiles, cytokines, and systemic humoral responses were studied. While no significant differences in polyp formations and epithelial disruptions were observed among the experimental groups, the local cell recruitment patterns slightly differed in animals that received either LPS or poly(I:C). Additionally, the local immune environments generated by LPS or poly(I:C) stimulation varied. LPS stimulation induced a marked Th1/Th17 response and predominantly neutrophilic nasal polyp formations, whereas poly(I:C) induced a Th2-skewed environment in neutrophilic nasal polyp development. Overall, our findings show that both cell recruitment patterns and local immune environments induced by these two stimuli differ, which may have implications in the physiopathology of rhinosinusitis with nasal polyp.

Topics: Animals; Cytokines; Disease Models, Animal; Enterotoxins; Humans; Lipopolysaccharides; Mice; Mice, Inbred BALB C; Nasal Mucosa; Nasal Polyps; Neutrophils; Ovalbumin; Poly I-C; Rhinitis, Allergic; Sinusitis; T-Lymphocyte Subsets

One subtype of chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by the development of a T-helper type 2 (Th2) response and eosinophilic infiltration. Here, we aimed to establish an eosinophilic CRSwNP murine model, which would be essential to understand the underlying pathogenesis and establish a treatment strategy. C57BL/6 mice were challenged intranasally with a mixture of an Aspergillus oryzae-derived protease (AP) and ovalbumin (OVA) for 6, 8, or 12 consecutive weeks (12 mice/group); control mice received the same volume of phosphate-buffered saline for 12 weeks (n = 12). Sinonasal samples were evaluated histologically, and interleukin (IL)-4, IL-5, IL-13, eotaxin, keratinocyte chemoattractant, and macrophage inflammatory protein-2 mRNA levels in sinonasal mucosa were measured by real-time PCR. Protein levels of Th2 cytokines, INF-γ, IL-17A, and chemokines in nasal lavage fluid, and total serum IgE were measured by ELISA. Greater eosinophil infiltration in the subepithelial layer was observed in the challenged groups, compared with the control group. Polypoid mucosal lesions were predominantly observed in the 12-week group, which also exhibited mucosal thickening on micro-CT scans. The IL-4, IL-5, and IL-13 mRNA and protein levels were elevated in the sinonasal mucosa and nasal lavage fluid. INF-γ and IL-17A were undetectable or not elevated relative to the control group levels. In contrast, eotaxin levels were particularly elevated in the sinonasal mucosa and nasal lavage fluid in the 12-week group. In conclusion, intranasal AP and OVA exposure successfully induced Th2-specific CRSwNP in a murine model.

Topics: Administration, Intranasal; Animals; Aspergillus; Chronic Disease; Cytokines; Disease Models, Animal; Eosinophilia; Instillation, Drug; Mice; Mice, Inbred C57BL; Nasal Polyps; Ovalbumin; Peptide Hydrolases; Rhinitis; Sinusitis

Nasal polyps (NPs) imply a refractory clinical course in patients with chronic rhinosinusitis (CRS). Previously, we showed that hypoxia-inducible factor (HIF) 1 could mediate nasal polypogenesis through epithelial-to-mesenchymal transition (EMT). Sirtuin 1 (SIRT1), a histone deacetylase, reportedly suppresses the transcriptional activity of HIF-1. Thus we hypothesized that SIRT1 attenuates nasal polyposis by inhibiting HIF-1-induced EMT.. We sought to determine the role of SIRT1 in patients with nasal polyposis.. The effects of SIRT1 on nasal polypogenesis were investigated in previously developed murine models. Immunohistochemistry, immunoblotting, and immunoprecipitation were done to evaluate SIRT1, EMT, and hypoxic markers in human nasal epithelial cells or sinonasal tissues from the mice and the patients with CRS with or without NPs.. SIRT1 transgenic mice had significantly fewer mucosal lesions with epithelial disruption and fewer NPs than wild-type (WT) mice. In addition, resveratrol (a SIRT1 activator) treatment suppressed nasal polypogenesis in WT mice; however, sirtinol (a SIRT1 inhibitor) administration increased the polyp burden in SIRT1 transgenic mice. In sinonasal specimens from patients with CRS, SIRT1 was downregulated in the mucosa from patients with polyps compared with levels seen in patients without polyps. SIRT1 overexpression or activation reversed hypoxia-induced EMT in human nasal epithelial cells. The intranasal transfection of a small hairpin SIRT1 lentiviral vector induced more nasal polypoid lesions in SIRT1 transgenic mice. Finally, mucosal extracts from patients with CRS without NPs increased SIRT1 expression in nasal epithelial cells, whereas those from patients with CRS with NPs did not.. SIRT1 suppressed NP formation, possibly because of inhibition of HIF-1-induced EMT. Thus nasal epithelium SIRT1 might be a therapeutic target for NPs.

Topics: Adult; Aged; Animals; Cell Line; DNA; Epithelial Cells; Epithelial-Mesenchymal Transition; Female; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Immunoglobulin E; Male; Mice, Inbred C57BL; Mice, Transgenic; Middle Aged; Nasal Mucosa; Nasal Polyps; Ovalbumin; Plasmids; RNA, Small Interfering; Sirtuin 1

Chronic rhinosinusitis (CRS) is one of the most common chronic diseases in adults in both developing and developed countries. The etiology and pathogenesis of CRS remain poorly understood, and the disease is refractory to therapy in many patients. Mast cell activation has been demonstrated in the sinonasal mucosa of patients with CRS; however, the specific contribution of mast cells to the development and pathogenesis of this disease has not been established.. The objective of this study was to investigate the role of mast cells in the development of CRS.. C57BL/6 wild-type and C57BL/6-Kit(W-sh/W-sh) mast cell-deficient mice were immunized by intraperitoneal allergen injection and subsequent chronic low dose intranasal allergen challenges. The sinonasal phenotypes of these groups were then evaluated and compared to saline-treated controls using radiologic, histologic, and immunologic methods.. Wild-type mice exposed to chronic intranasal allergen developed many features seen in human CRS, including mucosal thickening, cystic changes, polyp development, eosinophilia, goblet cell hyperplasia, and mast cell activation. In contrast, sinonasal pathology was significantly attenuated in mast cell-deficient mice subjected to the same chronic allergen protocol. Specifically, tissue eosinophilia and goblet cell hyperplasia were reduced by approximately 50% compared to wild-type levels. Surprisingly, none of the mast cell-deficient mice subjected to chronic allergen challenge developed cystic changes or polypoid changes in the nose or sinuses.. These data identify a critical role for mast cells in the development of many features of a mouse model of eosinophilic CRS, suggesting that therapeutic strategies targeting mast cells be examined in humans afflicted with this disease.

Topics: Allergens; Animals; Chronic Disease; Disease Models, Animal; Eosinophilia; Goblet Cells; Hyperplasia; Mast Cells; Maxillary Sinus; Mice; Mice, Inbred C57BL; Nasal Polyps; Ovalbumin; Paranasal Sinuses; Rhinitis; Sinusitis; X-Ray Microtomography

Topics: Cortisone; Desoxycorticosterone; Histamine; Humans; Hyaluronoglucosaminidase; Nasal Mucosa; Nasal Polyps; Ovalbumin; Sinusitis