Evidence that oncostatin M synergizes with IL-4 signaling to induce TSLP expression in chronic rhinosinusitis with nasal polyps.

BACKGROUND: Oncostatin M (OSM) may promote type 2 inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP) by inducing thymic stromal lymphopoietin (TSLP). OBJECTIVE: We sought to study the impact of OSM on TSLP synthesis and release from nasal epithelial cells (NECs). METHODS: OSM receptors, IL-4 receptors (IL-4R), and TSLP were evaluated in mucosal tissue and primary NECs from patients with CRSwNP by quantitative PCR and immunofluorescence. Air-liquid interface-cultured NECs were stimulated with cytokines, including OSM, and quantitative PCR, ELISA, Western blot, and flow cytometry were used to assess the expression of OSM receptors, IL-4R, and TSLP. RESULTS: Increased levels of OSM receptor ß chain (OSMRß), IL-4Rα, and TSLP were observed in nasal polyp tissues and primary epithelial cells from nasal polyps of patients with CRSwNP compared with control tissues or cells from control subjects. The level of expression of OSMRß in tissue was correlated with levels of both IL-4Rα and TSLP. OSM stimulation of NECs increased the expression of OSMRß and IL-4Rα. Stimulation with IL-4 plus OSM augmented the production of TSLP; the response was suppressed by a signal transducer and activator of transcription 6 inhibitor. Stimulation of NECs with IL-4 plus OSM increased the expression of proprotein convertase subtilisin/kexin 3, an enzyme that truncates and activates TSLP. CONCLUSIONS: OSM increases the expression of IL-4Rα and synergizes with IL-4 to induce the synthesis and release of TSLP in NECs. Because the combination of IL-4 and OSM also augmented the expression of proprotein convertase subtilisin/kexin 3, these results suggest that OSM can induce both synthesis and posttranslational processing/activation of TSLP, promoting type 2 inflammation.

A Novel ATM Antisense Transcript ATM-AS Positively Regulates ATM Expression in Normal and Breast Cancer Cells.

OBJECTIVE: The ataxia telangiectasia mutated (ATM) gene is a master regulator in cellular DNA damage response. The dysregulation of ATM expression is frequent in breast cancer, and is known to be involved in the carcinogenesis and prognosis of cancer. However, the underlying mechanism remains unclear. The bioinformatic analysis predicted a potential antisense transcript ATM-antisense (AS) from the opposite strand of the ATM gene. The purpose of this study was to identify ATM-AS and investigate the possible effect of ATM-AS on the ATM gene regulation. METHODS: Single strand-specific RT-PCR was performed to verify the predicted antisense transcript ATM-AS within the ATM gene locus. qRT-PCR and Western blotting were used to detect the expression levels of ATM-AS and ATM in normal and breast cancer cell lines as well as in tissue samples. Luciferase reporter gene assays, biological mass spectrometry, ChIP-qPCR and RIP were used to explore the function of ATM-AS in regulating the ATM expression. Immunofluorescence and host-cell reactivation (HCR) assay were performed to evaluate the biological significance of ATM-AS in ATM-mediated DNA damage repair. Breast cancer tissue samples were used for evaluating the correlation of the ATM-AS level with the ATM expression as well as prognosis of the patients. RESULTS: The ATM-AS significantly upregulated the ATM gene activity by recruiting KAT5 histone acetyltransferase to the gene promoter. The reduced ATM-AS level led to the abnormal downregulation of ATM expression, and impaired the ATM-mediated DNA damage repair in normal breast cells in vitro. The ATM-AS level was positively correlated with the ATM expression in the examined breast cancer tissue samples, and the patient prognosis. CONCLUSION: The present study demonstrated that ATM-AS, an antisense transcript located within the ATM gene body, is an essential positive regulator of ATM expression, and functions by mediating the binding of KAT5 to the ATM promoter. These findings uncover the novel mechanism underlying the dysregulation of the ATM gene in breast cancer, and enrich our understanding of how an antisense transcript regulates its host gene.

Studies on activation and regulation of the coagulation cascade in chronic rhinosinusitis with nasal polyps.

BACKGROUND: Increased activation of the coagulation cascade and diminished fibrinolysis combine to promote fibrin deposition and polyp formation in chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP). More information is needed concerning mechanisms of coagulation in CRSwNP. OBJECTIVE: We investigated the mechanisms as well as the initiation and regulation of coagulation cascade activation in CRS. METHODS: Samples were collected from 135 subjects with CRSwNP, 80 subjects with chronic CRS without nasal polyps (NP), and 65 control subjects. The levels of activated factor X (FXa), prothrombin fragment 1+2 (F1+2), thrombin-antithrombin complex, tissue factor (TF), and TF pathway inhibitor (TFPI) were monitored in CRS by real-time PCR, ELISA, immunohistochemistry, or immunofluorescence. Heteromeric complexes of TF with activated factor VII (FVII) and TF with activated FVII and FXa were assessed by coimmunoprecipitation and Western blotting. RESULTS: Increased levels of FXa, F1+2, and thrombin-antithrombin complex were detected in NP tissue compared to uncinate tissue from CRS and control subjects. Although free TF protein levels were not increased in NP, immunoprecipitation of TF in NP tissue revealed increased complexes of TF with FVII. Local expression of FVII was detected in sinonasal mucosa, and the ratio of TFPI to FXa was lower in NP tissue. CONCLUSION: The coagulation cascade is associated with NP compared to control and uncinate tissue from CRS patients, and TF and FVII are produced locally in sinonasal mucosa in patients. TF and FVII can activate the extrinsic coagulation pathway, suggesting that this pathway may activate fibrin deposition in CRSwNP. Reduced formation of the complex of FXa and TFPI in NP may reduce natural suppression of the extrinsic coagulation pathway in CRSwNP.

Cold-inducible RNA-binding protein contributes to tissue remodeling in chronic rhinosinusitis with nasal polyps.

BACKGROUND: Cold-inducible RNA-binding protein (CIRP) is a newly identified damage-associated molecular pattern molecule. Its roles beyond promoting inflammation and in human diseases are poorly understood. This study aimed to investigate the involvement of CIRP in chronic rhinosinusitis with nasal polyps (CRSwNP). METHODS: Immunohistochemistry, quantitative RT-PCR, and ELISA were used to detect the expression of CIRP and matrix metalloproteinases (MMPs) in sinonasal mucosal samples and nasal secretions. Human nasal epithelial cells (HNECs) and THP-1 cells, a human monocytic/macrophage cell line, were cultured to explore the regulation of CIRP expression and MMP expression. RESULTS: Cytoplasmic CIRP expression in nasal epithelial cells and CD68+ macrophages in sinonasal tissues, and CIRP levels in nasal secretions were significantly increased in both patients with eosinophilic and noneosinophilic CRSwNP as compared to those in control subjects. IL-4, IL-13, IL-10, IL-17A, TNF-α, Dermatophagoides pteronyssinus group 1, and lipopolysaccharide induced the production and secretion of CIRP from HNECs and macrophages differentiated from THP-1 cells. CIRP promoted MMP2, MMP7, MMP9, MMP12, and vascular endothelial growth factor A (VEGF-A) production from HNECs, macrophages differentiated from THP-1 cells, and polyp tissues, which was inhibited by the blocking antibody for Toll-like receptor 4, but not advanced glycation end products. The expression of MMPs and VEGF-A in tissues correlated with CIRP levels in nasal secretions in patients with CRSwNP. CONCLUSIONS: The upregulated production and release of CIRP from nasal epithelial cells and macrophages may contribute to the edema formation in both eosinophilic and noneosinophilic CRSwNP by inducing MMP and VEGF-A production from epithelial cells and macrophages.

[The NOXA promoter could function as an active enhancer to regulate the expression of BCL2 in the apoptosis response].

The transcription of eukaryotic genes is regulated by both proximal promoters and distal enhancers. Some promoters also have enhancer activity. NOXA and BCL2 are pro-apoptotic and anti-apoptotic members of the BCL2 family of protein, respectively. Our previous study has found that the NOXA gene promoter and the BCL2 gene promoter interact at the level of three-dimensional chromatin structure. Moreover, the NOXA gene promoter region displays histone modifications characteristic of both promoters and enhancers. This study aimed to explore whether and when the NOXA promoter could act as an active enhancer to regulate BCL2 expression. Based on the apoptosis model of MCF-7 cells induced by camptothecin, we used chromosome conformation capture (3C), quantitative real-time PCR (qRT-PCR) and the luciferase reporter gene technology to demonstrate that the NOXA promoter could function as an active enhancer and physically interact with the BCL2 promoter through chromatin looping. The regulatory properties of the NOXA promoter were closely related to the strength of the apoptosis stimulation. Under weak apoptotic stimulation (1 µmol/L camptothecin treatment), the NOXA promoter mainly functioned as an enhancer; with the enhancement of apoptotic stimulation (10 µmol/L camptothecin treatment), the NOXA promoter activity increased and mainly regulated the expression of the gene itself to promote apoptosis. Chromatin immunoprecipitation (ChIP) confirmed that the dynamic changes of the promoter activity and enhancer activity in the NOXA promoter region are consistent with its histone modification marks. This study provides new clues for further exploring the mechanism underlying cooperative response of BCL2 family member to apoptosis stimuli.

Pathophysiologic mechanisms of chronic rhinosinusitis and their roles in emerging disease endotypes.

OBJECTIVE: Chronic rhinosinusitis (CRS) is a heterogeneous disorder with distinct pathophysiologic mechanisms. Based on transcription factor expression and cytokine production patterns in different innate lymphoid cell (ILC) types, in parallel with those of adaptive CD4+ T-helper (TH) cells and CD8+ cytotoxic T (Tc) cells, new perspectives on endotypes of patients are emerging for the immune response deviation into type 1 (orchestrated by ILC1s and Tc1, and TH1 cells), type 2 (characterized by ILC2s and Tc2 and TH2 cells), and type 3 (mediated by ILC3s and Tc17 and TH17 cells). In addition, cluster analysis has been applied to endotyping of CRS in recent years, which has provided additional novel insights into CRS pathogenesis. This review assessed pathologic mechanisms of CRS based on type 1, 2, and 3 immune responses and how they inform us to begin to understand CRS endotypes. This review also assessed recent cluster analysis studies of CRS endotypes. The impact of endotype on therapeutic management of CRS also is summarized. DATA SOURCES: Review of published literature. STUDY SELECTIONS: Relevant literature concerning CRS endotypes and possible underlying mechanisms was obtained from a PubMed search and summarized. RESULTS AND CONCLUSION: CRS with and without nasal polyps are composed of distinct endotypes with distinct deviated immune responses, pathogenic mechanisms, and different responses to medical and surgical treatment. An endotype of CRS with prominent type 2 immune responses is the best-studied endotype and generally can benefit from treatment with steroids and specific type 2 disrupting biologics.

IgD-activated mast cells induce IgE synthesis in B cells in nasal polyps.

BACKGROUND: Although upregulated expression of local IgD has been reported in patients with chronic rhinosinusitis (CRS), its function is unclear. OBJECTIVE: We sought to explore the expression and function of soluble IgD in patients with CRS, particularly CRS with nasal polyps. METHODS: IgD levels in sinonasal mucosa were analyzed by using RT-PCR and ELISA. Numbers and phenotypes of IgD+ cells were studied by means of immunohistochemistry, immunofluorescence, and flow cytometry. HMC-1 cells, a human mast cell line, and mast cells purified from eosinophilic polyps were cultured alone or with naive B cells purified from peripheral blood. The antigen specificity of nasal IgD was investigated by using ELISA. RESULTS: The mRNA expression of immunoglobulin heavy constant delta gene, numbers of IgD+ cells, and protein levels of secretory IgD in sinonasal mucosa were increased in patients with CRS with or without nasal polyps compared with control subjects. Numbers of IgD+ plasmablasts were increased in both eosinophilic and noneosinophilic polyps, whereas numbers of IgD+ mast cells were only increased in eosinophilic polyps. Cross-linking IgD induced serum preincubated HMC-1 cells and polyp mast cells to produce B-cell activating factor, IL-21, IL-4, and IL-13 and to promote IgM, IgG, IgA, and IgE production from B cells. In eosinophilic polyps expression of those B cell-stimulating factors in mast cells and close contact between mast cells and B cells were found. Moreover, positive correlations of total IgD levels with total IgE levels and eosinophilia and upregulation of specific IgD against house dust mites were discovered in eosinophilic polyps. CONCLUSION: IgD-activated mast cells can facilitate IgE production and eosinophilic inflammation in patients with CRS with nasal polyps.

Ectopic lymphoid tissues support local immunoglobulin production in patients with chronic rhinosinusitis with nasal polyps.

BACKGROUND: The contribution of ectopic lymphoid tissues (eLTs) to local immunoglobulin hyperproduction in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) is unclear. OBJECTIVE: We sought to explore the cellular basis, formation mechanisms, and function of eLTs in patients with CRSwNP. METHODS: We graded lymphoid aggregations in sinonasal mucosa and histologically studied their structures. The expression of lymphorganogenic factors and molecules required for immunoglobulin production was measured by using real-time PCR, and their localization was analyzed by means of immunohistochemistry and immunofluorescence. The phenotype of follicular helper T cells was analyzed by performing flow cytometry. Immunoglobulin levels were quantified by using the Bio-Plex assay or ImmunoCAP system. Nasal tissue explants were challenged ex vivo with Dermatophagoides pteronyssinus group 1 (Der p 1), and the expression of Iε-Cµ and Iε-Cγ circle transcripts was detected by using seminested PCR. RESULTS: Increased formation of eLTs with germinal center-like structures was discovered in patients with eosinophilic (20.69%) and noneosinophilic (17.31%) CRSwNP compared with that in patients with chronic rhinosinusitis without nasal polyps (5.66%) and control subjects (3.70%). The presence of eLTs was associated with increased expression of lymphorganogenic and inflammatory chemokines and cytokines, as well as their receptors. The expression of molecules required for immunoglobulin production, generation of follicular helper T cells, and production of IgE in eosinophilic polyps and IgG and IgA in both eosinophilic and noneosinophilic polyps were predominantly upregulated in patients with eLTs. After Der p 1 challenge ex vivo, Iε-Cµ transcript was detected only in eosinophilic polyps with eLTs but not in polyps without eLTs and noneosinophilic polyps. CONCLUSION: eLTs might support local immunoglobulin production and therefore significantly contribute to the development of CRSwNP.

Distinct mucosal immunopathologic profiles in atopic and nonatopic chronic rhinosinusitis without nasal polyps in Central China.

BACKGROUND: The role of atopy to aeroallergens in chronic rhinosinusitis without nasal polyps (CRSsNP) remains unclear. This study aimed to investigate the mucosal immunopathologic characteristics of CRSsNP with and without atopy to inhalant allergens. METHODS: Thirteen nonatopic CRSsNP patients, 9 atopic CRSsNP patients, and 11 nonatopic control subjects were enrolled in this study. The expression of type 1, 2, and 17 cytokines, growth factors, and chemokines for T cell subsets and granulocytes in sinonasal mucosa was detected using Bio-Plex suspension chip technology or enzyme-linked immunosorbent assay (ELISA). Subjective symptoms were scored on a visual analogue scale (VAS), while disease severity on computed tomography (CT) was graded by the Lund-Mackay CT scoring system. RESULTS: There was no significant difference in VAS and CT scores between atopic and nonatopic CRSsNP. Compared with control, both atopic and nonatopic CRSsNP demonstrated increased interferon γ (IFN-γ) levels in sinonasal mucosa. In contrast, although no difference in interleukin 5 (IL-5), IL-13 and eotaxin-1 expression, or mucosal eosinophil infiltration, was found between the control and whole CRSsNP group, atopic CRSsNP manifested an increased expression of IL-5, IL-13 and eotaxin-1, as well as an enhanced infiltration of mucosal eosinophils in comparison with control and nonatopic CRSsNP. Mucosal eosinophil infiltration correlated with IL-5 and eotaxin-1 expression. No difference in IL-12, IL-4, IL-6, IL-17A, IL-8, myeloperoxidase, "regulated upon activation normal T cell expressed and presumably secreted" (RANTES), or chemokine (C-X-C motif) ligand 10 (CXCL10) protein expression was found among control, atopic CRSsNP, and nonatopic CRSsNP. CONCLUSION: Atopic and nonatopic CRSsNP have distinct mucosal immunopathologic profiles. CRSsNP is a heterogeneous disorder consisting of multiple groups of biological subtypes, or "endotypes," which may argue for different therapeutic strategies.

Nasal IL-4(+)CXCR5(+)CD4(+) T follicular helper cell counts correlate with local IgE production in eosinophilic nasal polyps.

BACKGROUND: Locally produced IgE contributes to the initiation and development of eosinophilic inflammation in eosinophilic nasal polyps independent of systemic atopy. However, whether CXCR5(+)CD4(+) T follicular helper (TFH) cells are involved in local IgE production at mucosal sites remains unexplored. OBJECTIVE: We sought to explore the presence, phenotype, and function of CXCR5(+)CD4(+) TFH cells in eosinophilic nasal polyp tissues compared with noneosinophilic nasal polyp and control normal nasal tissues. METHODS: TFH cell-surface phenotypes and subsets and B-cell subsets in nasal tissues and peripheral blood were studied by means of flow cytometry. Immunohistochemistry was used to detect the tissue location of TFH cells. Sorted nasal TFH cells and CXCR5(-) T cells were cultured with autologous naive B cells purified from blood. RESULTS: Nasal TFH cells expressed inducible costimulator, programmed cell death protein 1, and the transcription factor B-cell lymphoma 6 (Bcl-6) at an intermediate level when compared with bona fide TFH cells in tonsils and circulating TFH cells. Although counts of total TFH cells and IL-21(+), IFN-γ(+), and IL-17(+) TFH cells were increased in both eosinophilic and noneosinophilic nasal polyp tissues compared with those in normal nasal tissues, IL-4(+) TFH cell counts were only increased in eosinophilic polyp tissues. IL-4 and IL-21 were involved in polyp TFH cell-induced IgE production from naive B cells, and nasal IL-4(+) TFH cell counts correlated highly with local IgE levels in vivo. IL-4(+)Bcl-6(+)CD4(+) TFH cells were identified in ectopic lymphoid structures in eosinophilic nasal polyps. TFH cells also positively correlated with germinal center B cells and plasma cells in nasal tissues. CONCLUSION: Nasal IL-4(+) TFH cells might be involved in local IgE production in eosinophilic nasal polyps.

Clarithromycin and dexamethasone show similar anti-inflammatory effects on distinct phenotypic chronic rhinosinusitis: an explant model study.

BACKGROUND: Phenotype of chronic rhinosinusitis (CRS) may be an important determining factor of the efficacy of anti-inflammatory treatments. Although both glucocorticoids and macrolide antibiotics have been recommended for the treatment of CRS, whether they have different anti-inflammatory functions for distinct phenotypic CRS has not been completely understood. The aim of this study is to compare the anti-inflammatory effects of clarithromycin and dexamethasone on sinonasal mucosal explants from different phenotypic CRS ex vivo. METHODS: Ethmoid mucosal tissues from CRSsNP patients (n = 15), and polyp tissues from eosinophilic (n = 13) and non-eosinophilic (n = 12) CRSwNP patients were cultured in an ex vivo explant model with or without dexamethasone or clarithromycin treatment for 24 h. After culture, the production and/or expression of anti-inflammatory molecules, epithelial-derived cytokines, pro-inflammatory cytokines, T helper (Th)1, Th2 and Th17 cytokines, chemokines, dendritic cell relevant markers, pattern recognition receptors (PRRs), and tissue remodeling factors were detected in tissue explants or culture supernatants by RT-PCR or ELISA, respectively. RESULTS: We found that both clarithromycin and dexamethasone up-regulated the production of anti-inflammatory mediators (Clara cell 10-kDa protein and interleukin (IL)-10), whereas down-regulated the production of Th2 response and eosinophilia promoting molecules (thymic stromal lymphopoietin, IL-25, IL-33, CD80, CD86, OX40 ligand, programmed cell death ligand 1, CCL17, CCL22, CCL11, CCL5, IL-5, IL-13, and eosinophilic cationic protein) and Th1 response and neutrophilia promoting molecules (CXCL8, CXCL5, CXCL10, CXCL9, interferon-γ, and IL-12), from sinonasal mucosa from distinct phenotypic CRS. In contrast, they had no effect on IL-17A production. The expression of PRRs (Toll-like receptors and melanoma differentiation-associated gene 5) was induced, and the production of tissue remodeling factors (transforming growth factor-ß1, epidermal growth factor, basic fibroblast growth factor, platelet derived growth factor, vascular endothelial growth factor, and matrix metalloproteinase 9) was suppressed, in different phenotypic CRS by dexamethasone and clarithromycin in comparable extent. CONCLUSIONS: Out of our expectation, our explant model study discovered herein that glucocorticoids and macrolides likely exerted similar regulatory actions on CRS and most of their effects did not vary by the phenotypes of CRS.

Disease-specific T-helper cell polarizing function of lesional dendritic cells in different types of chronic rhinosinusitis with nasal polyps.

RATIONALE: Although eosinophilic and noneosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP) exhibit distinct T-helper (Th) responses, the underlying mechanisms remain unclear. OBJECTIVES: To clarify the phenotypes and Th-cell polarizing functions of dendritic cells (DCs) in different types of CRSwNP. METHODS: DC subsets, their surface phenotypes, and Th-cell subsets were studied by means of immunohistochemistry and flow cytometry. The sorted lesional DCs were activated or cultured with autologous naive CD4(+) T cells, and cytokine production was determined by ELISA. Thymic stromal lymphopoietin and osteopontin expression were detected by means of reverse-transcriptase polymerase chain reaction. MEASUREMENTS AND MAIN RESULTS: Although elevated local Th1 and Th17 cells were noted in both eosinophilic and noneosinophilic CRSwNP, increased Th2 cells were found only in eosinophilic CRSwNP. Increased numbers of myeloid DCs, plasmacytoid DCs, and their activated subsets were found in both types of CRSwNP, but only myeloid DCs and plasmacytoid DCs from eosinophilic CRSwNP demonstrated an up-regulation of OX40 ligand (OX40L) and programmed death ligand 1(PD-L1) expression. Lesional DCs from both types of CRSwNP produced enhanced levels of IL-12, IL-6, and transforming growth factor-ß, and induced increased Th1 and Th17 responses; in contrast, only DCs from eosinophilic CRSwNP induced obviously enhanced Th2 responses, when cocultured with naive CD4(+) T cells. Blockade of OX40L and PD-L1 on lesional DCs from eosinophilic CRSwNP suppressed Th2 responses, but promoted Th1 responses in DC-T cell coculture. CONCLUSIONS: Distinct subsets of lesional DCs were found in eosinophilic and noneosinophilic CRSwNP, where OX40L/PD-L1(+) lesional DCs in eosinophilic CRSwNP could prime Th2 cells, whereas the low OX40L/PD-L1-expressing lesional DCs in noneosinophilic CRSwNP primarily induced Th1/Th17 cells.

Expression of microRNA machinery proteins in different types of chronic rhinosinusitis.

OBJECTIVES/HYPOTHESIS: Dysregulation of microRNAs (miRNAs) has recently been shown in chronic rhinosinusitis (CRS), the biogenesis and function of which are modulated by miRNA machinery proteins. The expression of these proteins in inflammatory airway diseases is unclear. The aim of this study was to investigate the expression of miRNA machinery components in CRS. STUDY DESIGN: Case-control experimental study. METHODS: The mRNA expression levels of miRNA machinery components including Drosha, Dicer, protein activator of the interferon-induced protein kinase (PACT), human immunodeficiency virus transactivating response RNA-binding protein, fragile X mental retardation protein, and argonaute 2/eukaryotic translation initiation factor 2C, 2 in nasal biopsies from control, CRS without nasal polyps (CRSsNP), eosinophilic, and noneosinophilic CRS with nasal polyps (CRSwNP) subjects were determined by quantitative reverse transcription polymerase chain reaction. Immunohistochemical staining was employed to examine the protein expression of PACT and the cellular source of PACT. RESULTS: Among the tested components, only PACT mRNA expression was found to be altered in CRS, the levels of which were upregulated in CRSwNP as compared with control. In comparison with control and CRSsNP, PACT protein expression was also significantly upregulated in CRSwNP, with a further increase in eosinophilic CRSwNP. PACT was mainly expressed in CD138(+) plasma cells. A higher percentage of PACT-positive plasma cells in total plasma cells was detected in eosinophilic CRSwNP than in noneosinophilic CRSwNP. PACT protein expression correlated with disease severity and eosinophil infiltration. CONCLUSIONS: PACT may be associated with the plasma cell function and eosinophilic inflammation in CRSwNP. However, further experimentation is needed to clarify the functions of PACT.

Diagnostic significance of blood eosinophil count in eosinophilic chronic rhinosinusitis with nasal polyps in Chinese adults.

OBJECTIVES/HYPOTHESIS: Over half of chronic rhinosinusitis with nasal polyps (CRSwNP) patients in China show noneosinophilic inflammation. The aim of this study was to compare the clinical characteristics of eosinophilic and noneosinophilic CRSwNP and to identify the predictors of eosinophilic CRSwNP. STUDY DESIGN: A retrospective study. METHODS: There were 155 CRSwNP patients enrolled in the Tongji cohort. Eosinophilic CRSwNP was diagnosed according to our previously published histologic criterion. The demographic and clinical features were compared between eosinophilic and noneosinophilic CRSwNP. Factors associated with eosinophilic CRSwNP were determined with regression analysis, and optimal cutoff points of the predictors were determined by a receiver operating characteristic curve. The optimal cutoff points of the predictors were validated in an independent group of 35 CRSwNP patients referred to as the Taizhou cohort. RESULTS: A male preponderance, a higher prevalence of smoking and atopy, and higher peripheral blood eosinophil absolute count and percentage and blood IgE levels were found in eosinophilic CRSwNP compared with noneosinophilic CRSwNP. Peripheral eosinophil absolute count and percentage were independently and significantly associated with eosinophilic CRSwNP. An absolute blood eosinophil count ≥ 0.215 × 10(9) /L yielded a sensitivity of 74.2% and a specificity of 86.5%, and a blood eosinophil percentage ≥ 3.05% yielded a sensitivity of 80.3% and a specificity of 75.3% for the diagnosis of eosinophilic CRSwNP in the Tongji cohort. The validation study in the Taizhou cohort revealed a lower sensitivity and specificity. CONCLUSIONS: Eosinophilic and noneosinophilic CRSwNP displayed significant differences in certain clinical features. Peripheral blood eosinophil count could distinguish eosinophilic and noneosinophilic CRSwNP in Chinese adults.

Overexpression of miR-125b, a novel regulator of innate immunity, in eosinophilic chronic rhinosinusitis with nasal polyps.

RATIONALE: Eosinophilic chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) represents a hard-to-treat subtype of CRS. OBJECTIVES: To determine the pattern of expression and biologic role of microRNAs (miRNAs) in CRS, particularly in eosinophilic CRSwNP. METHODS: Global miRNA expression in sinonasal mucosa from controls, CRS without nasal polyps (CRSsNP), and patients with eosinophilic CRSwNP was compared using miRNA microarrays. MiR-125b expression was detected by means of quantitative reverse-transcriptase polymerase chain reaction. The cellular localization of miR-125b was determined by in situ hybridization. MiR-125b functional assays were performed on airway epithelial cells and mice. MiR-125b expression regulation was studied by tissue and cell culture. MEASUREMENTS AND MAIN RESULTS: CRSsNP and eosinophilic CRSwNP exhibited distinct miRNA expression profiles. MiR-125b was specifically up-regulated in eosinophilic CRSwNP. MiR-125b was mainly expressed by sinonasal and bronchial epithelial cells. EIF4E-binding protein 1 (4E-BP1) was identified as a direct target of miR-125b. MiR-125b mimic or inhibitor enhanced or decreased IFN-α/ß production elicited by dsRNA in vitro or in vivo, respectively. 4E-BP1 expression was decreased, whereas IFN regulatory factor-7 and IFN-ß expression was increased, in eosinophilic CRSwNP. IFN-ß mRNA levels positively correlated with IL-5 mRNA levels and eosinophil infiltration in sinonasal mucosa. IFN-ß stimulated B cell-activating factor of the tumor necrosis factor family production in airway epithelial cells. miR-125b could be induced by lipopolysaccharide, dsRNA, and IL-10. CONCLUSIONS: The up-regulated expression of miR-125b may enhance type I IFN expression through suppressing 4E-BP1 protein expression in airway epithelial cells, which potentially contributes to mucosal eosinophilia in eosinophilic CRSwNP.

Clara cell 10-kD protein suppresses chitinase 3-like 1 expression associated with eosinophilic chronic rhinosinusitis.

RATIONALE: Clara cell 10-kD (CC10) protein, an antiinflammatory molecule, is involved in inflammatory upper airway diseases, but its regulatory role is unclear, particularly in the process of chronic rhinosinusitis (CRS). OBJECTIVES: To investigate the regulatory mechanisms of CC10 in eosinophilic CRS (ECRS) using an allergic mouse model. METHODS: Homozygous CC10-knockout mice were used to establish an allergic ECRS model. Phenotypic changes were examined by histology, cytokine ELISA, and gene microarray analysis. Differential expression of chitinase 3-like 1 (CHI3L1) was verified by quantitative reverse transcriptase-polymerase chain reaction and immunohistochemistry. The functional role of CHI3L1 in vivo was assessed by the use of anti-CHI3L1 antibody in ECRS mice. CHI3L1 gene expression regulated by inflammatory cytokines and CC10 protein was performed using BEAS-2B cell line. MEASUREMENTS AND MAIN RESULTS: Compared with wild-type mice, a significantly greater extent of inflammatory cell infiltration and tissue remodeling was found in CC10-knockout ECRS mice, which was associated with significantly higher levels of various cytokines and eotaxin-1. CHI3L1 was up-regulated in ECRS mice with a significant further increase in CC10-knockout mice. Anti-CHI3L1 treatment markedly ameliorated eosinophilic inflammation. Furthermore, nasal mucosal CC10 gene transfer in CC10-knockout mice attenuated eosinophilic inflammation and suppressed the levels of CHI3L1. Moreover, significantly up-regulated expression of CHI3L1 was noted in human ECRS. IL-1beta, tumor necrosis factor-alpha, and IL-13 were found to up-regulate CHI3L1 expression in BEAS-2B cells, whereas CC10 inhibited such up-regulation. CONCLUSIONS: These results suggest that CHI3L1 is a novel molecule involved in ECRS and that CC10 plays a regulatory role in ECRS, presumably by attenuating CHI3L1 expression.

Let-7a microRNA functions as a potential tumor suppressor in human laryngeal cancer.

MicroRNAs (miRNAs) are endogenously expressed non-coding RNAs, which are involved in the gene expression regulation. Lethal-7a (let-7a) is a founding member of miRNA family and recently it was found to be associated with several cancers, such as lung and colon cancers. In the present study, we found that let-7a miRNA expression was significantly downregulated both in human laryngeal squamous cancer tissues and in Hep-2 cells, a laryngeal cancer cell line, as compared with adjacent normal tissues and BEAS-2B cells, respectively. Moreover, we found that let-7a expression levels were significantly further decreased in non-differentiated (G3) cancer tissues as compared with moderately and well differentiated cancer tissues (G2 and G1), although no significant difference in let-7a expression levels between the cancer specimens with different T stages or specimens from patients with different lymph node metastasis status was revealed. In Hep-2 cells, let-7a mimics transfection markedly suppressed proliferation and induced apoptosis of Hep-2 cells under the treatment of diamminedichloroplatinum or not and downregulated RAS and c-MYC protein expression without affecting the mRNA levels. In parallel, RAS and c-MYC protein levels were found significantly upregulated only in cancer tissues with downregulated let-7a expression. Thus, we propose that let-7a may be a tumor suppressor in laryngeal cancer by inhibiting cell growth, inducing cell apoptosis and downregulating the oncogenes expression.

Distinct immunopathologic characteristics of various types of chronic rhinosinusitis in adult Chinese.

BACKGROUND: Chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP) is reported to be different in inflammatory patterns of the sinonasal mucosa in white patients. Studies in nonwhite populations may further be helpful to understand the pathogenic mechanisms of CRS. OBJECTIVE: To investigate the immunopathologic profiles of CRSwNP and CRSsNP in adult Chinese. METHODS: Histologic characteristics of surgical samples were analyzed in 50 controls, 94 CRSsNP patients, and 151 CRSwNP patients. Tissue samples from 17 controls, 36 CRSsNP patients, and 45 CRSwNP patients were stained for CD3, CD4, CD8, CD20, CD68, myeloperoxidase, and dendritic cell lysosome-associated membrane protein. Expression profiles of transcription factors of T-cell subsets in relation to cytokines and a marker of natural killer T cell (Valpha24) were examined by means of quantitative RT-PCR. RESULTS: Over half of CRSwNP patients presented noneosinophilic inflammation. CRSwNP had a higher number of eosinophils, plasma cells, and CD3(+), CD8(+), CD20(+), and CD68(+) cells and a lower myeloperoxidase expression rate than CRSsNP. Expression levels of transcription factors and cytokines of T(H)1/T(H)2/T(H)17 were increased, whereas the expression rate of Forkhead box p3 and TGF-beta1 was decreased in both CRSsNP and CRSwNP compared with controls. Comparing CRSsNP and CRSwNP, CRSsNP had higher levels of IFN-gamma expression, whereas only eosinophilic CRSwNP demonstrated an enhanced expression of GATA-3 and IL-5. Compared with noneosinophilic CRSwNP, an exaggerated T(H)2/T(H)17 reaction and Valpha24 expression were found in eosinophilic CRSwNP. CONCLUSION: Both Chinese CRSsNP and CRSwNP patients demonstrate impaired regulatory T cell function and enhanced T(H)1/T(H)2/T(H)17 responses. CRSsNP is confirmed to be a predominant T(H)1 milieu, whereas T(H)2 skewed inflammation with predominant T(H)17 reactions, and infiltration of natural killer T cells can be demonstrated only in eosinophilic CRSwNP, but not in noneosinophilic CRSwNP.

Lack of association of Clara cell 10-kDa protein gene variant with chronic rhinosinusitis in a Chinese Han population.

BACKGROUND: Clara cell 10-kDa protein (CC10) is an anti-inflammatory molecule and has been implicated in the involvement of the pathogenesis of asthma and chronic rhinosinusitis (CRS). A single nucleotide polymorphism (SNP) in CC10 gene (A + 38G) was previously shown to be associated with asthma and plasma CC10 levels. The purpose of this study is to examine whether there is an association between the CC10 A + 38G SNP, plasma CC10 levels, and CRS in a central Chinese population of Han nationality. METHODS: The CC10 A + 38G SNP was analyzed by means of polymerase chain reaction with restriction fragment length polymorphism and plasma CC10 levels were measured using enzyme-linked immunosorbent assay in 220 patients with CRS (90 patients with nasal polyps [NPs] and 130 patients without NPs) and 180 healthy control subjects. Among 220 patients with CRS, 108 patients were atopic subjects. Severity of disease was determined by coronal computed tomography (CT) scan in CRS patients, which was graded according to Lund and Mackay. RESULTS: The frequency of the A allele was 0.394, which was not significantly higher than the frequencies of other reported ethnic groups except for German. No association between the CC10 A + 38G SNP and CRS, any subgroup of CRS, or CRS severity could be found. Although subjects carrying the AA genotype had a significantly lower plasma CC10 concentration than those carrying the GG and GA genotypes in both CRS and control groups (p = 0.00 for all), no association was found between the plasma CC10 levels and CRS phenotype. CONCLUSION: The CC10 A + 38G SNP may not exert a substantial influence on the development of CRS in the Chinese Han population.

Histological and immunological observations of bacterial and allergic chronic rhinosinusitis in the mouse.

BACKGROUND: The purpose of this study was to elucidate histological and immunologic features of mouse models of bacterial chronic rhinosinusitis (BCRS) and allergic chronic rhinosinusitis (ACRS). METHODS: A BCRS mouse model was established using Streptococcus pneumoniae inoculation plus Merocel (Medtronic, Jacksonville, FL) ostiomeatal obstruction for 12 weeks. An ACRS mouse model was developed by means of ovalbumin (OVA) i.p. injection and subsequent repeated OVA intranasal challenge for 12 weeks. Histological changes of sinonasal mucosa of both models were examined by means of hematoxylin and eosin staining for general morphology and inflammatory cell, periodic acid-Schiff staining for goblet cell, and Masson-trichrome staining for collagen. Enzyme-linked immunosorbent assay was used to detect the concentrations of various cytokines in nasal lavage fluid. RESULTS: Polymorphonuclear neutrophil infiltration in lamina propria was more obvious in the BCRS model, whereas eosinophil infiltration was more apparent in the ACRS model. Significant goblet cell and subepithelial gland hyperplasia, subepithelial fibrosis, epithelial thickening, and mononuclear cell infiltration were shown in both models with more severe extent found in the ACRS model. Interleukin (IL)-6 and tumor necrosis factor alpha levels in NLF from both models were increased and peaked at 1 week. Interferon gamma levels were also up-regulated in both models but reached maximum at 1 week in the BCRS model and 4 weeks in the ACRS model. IL-8 (CXCL8) levels were only increased in BCRS mice and peaked at 1 week, whereas IL-5, IL-13, and eotaxin (CCL11) levels were only enhanced in ACRS mice and peaked at 1 week. The Th1/Th2 ratio in BCRS mice was significantly higher than that in ACRS mice (6.68 +/- 2.33 versus 1.37 +/- 0.86; p < 0.01). CONCLUSION: Histological and immunologic features of BCRS and ACRS mouse models were similar to those of human noneosinophilic and eosinophilic CRS, respectively. BCRS and ACRS mouse models have distinct immunologic characteristics and are applicable for CRS research.