Project description:Epigenetic alterations may represent new therapeutic targets and/or biomarkers of allergic rhinitis (AR). Our aim was to examine genome-wide epigenetic changes induced by controlled pollen exposure in the Environmental Exposure Unit (EEU). 38 AR-sufferers and 8 non-allergic controls were exposed to grass pollen for 3h on two consecutive days. We interrogated DNA methylation at baseline and 3h in peripheral blood mononuclear cells (PBMCs) using the Infinium Methylation 450K array. We corrected for demographics, cell composition, and multiple testing (Benjamini-Hochberg), and verified hits using bisulfite PCR-pyrosequencing and qPCR. To extend these findings to a clinically relevant tissue, we investigated DNA methylation and gene expression of mucin 4 (MUC4), in nasal brushings from a separate validation cohort exposed to birch pollen. In PBMCs of allergic rhinitis participants, 42 sites showed significant DNA methylation changes of 2% or greater. DNA methylation changes in tryptase gamma 1 (TPSG1), schlafen 12 (SLFN12) and MUC4 in response to exposure were validated by pyrosequencing. SLFN12 DNA methylation significantly correlated with symptoms (p<0.05), and baseline DNA methylation pattern was found to be predictive of symptom severity upon grass allergen exposure (p<0.05). Changes in MUC4 DNA methylation in nasal brushings in the validation cohort correlated with drop in peak nasal inspiratory flow (Spearman r = 0.314, p = 0.034), and MUC4 gene expression was significantly increased (p<0.0001). This study revealed novel and rapid epigenetic changes upon exposure in a controlled allergen challenge facility, identified baseline epigenetic status as a predictor of symptom severity.
Project description:Analysis of nasal epithelial cells from adult patients with seasonal allergic rhinitis and from non allergic controls. Results provide insight into the molecular mechanisms associated with inflammatory responses in nasal mucosa. Total RNA was obtained from nasal epithelial cells of 7 seasonal allergic rhinitis patients and 5 non-allergic control subjects
Project description:To elucidate the epithelial cell diversity within the nasal inferior turbinates, a comprehensive investigation was conducted comparing control subjects to individuals with house dust mite-induced allergic rhinitis. This study aimed to delineate the differential expression profiles and phenotypic variations of epithelial cells in response to allergic rhinitis. This research elucidated distinct subpopulations and rare cell types of epithelial cells within the nasal turbinates, discerning alterations induced by allergic rhinitis. Furthermore, by interrogating transcriptomic signatures, the investigation provided novel insights into the cellular dynamics and immune responses underlying allergic rhinitis pathogenesis
Project description:The link between upper and lower airways in patients with both asthma and allergic rhinitis is still poorly understood. As the biological complexity of these disorders can be captured by gene expression profiling we hypothesized that the clinical expression of rhinitis and/or asthma is related to differential gene expression between upper and lower airways epithelium. We used micro array to profile gene expression of primary nasal and bronchial epithelial cells from the same individuals and examining the impact of allergic rhinitis with and without concomitant allergic asthma on expression profiles. 17 subjects were included in a cross-sectional study (6 allergic asthma and allergic rhinitis; 5 allergic rhinitis; 6 healthy controls). RNA was extracted from isolated and cultured epithelial cells from bronchial brushes and nasal biopsies, and analyzed by microarray (Affymetrix U133+ PM Genechip Array).
Project description:Analysis of nasal epithelial cells from adult patients with seasonal allergic rhinitis and from non allergic controls. Results provide insight into the molecular mechanisms associated with inflammatory responses in nasal mucosa.
Project description:Rhinovirus infections are the most common cause of asthma exacerbations. The complex responses by the airway epithelium to rhinovirus can be captured by gene expression profiling. We hypothesized that the upper and lower airway epithelium exhibit differential responses to double-stranded RNA (dsRNA), and that this is modulated by the presence of asthma and allergic rhinitis. Identification of dsRNA-induced gene expression profiles by microarray of primary nasal and bronchial epithelial cells from the same individuals and examining the impact of allergic rhinitis with and without concomitant allergic asthma on expression profiles. 17 subjects were included in a cross-sectional study (6 allergic asthma and allergic rhinitis; 5 allergic rhinitis; 6 healthy controls). RNA was extracted from isolated and cultured epithelial cells that were stimulated with Poly(I:C) for 24 hours from bronchial brushes and nasal biopsies, and analyzed by microarray (Affymetrix U133+ PM Genechip Array).
Project description:Background: In asthma, airway epithelium remodeling can already be detected during childhood, and epithelial cells are more susceptible to virus and oxidative stress. Their exact role in natural history and severity of children allergic respiratory disease remains however surprisingly unexplored. Aim: To analyze dysfunctions of epithelium in dust mite allergic respiratory disease (rhinitis ± asthma) in children. Methods: Expression profilings of nasal epithelial cells collected by brushing were performed on Affymetrix Hugene 1.0 ST arrays. All allergic patients were sensitized to dust mite. 19 patients had an isolated allergic rhinitis (AR). 14 patients had AR associated with asthma. Patients were compared to 12 controls, their severity and control being assessed according to NAEPP and ARIA criteria. Infections by respiratory viruses were excluded by real-time PCR measurements. Results: 61 probes were able to distinguish allergic rhinitis children from healthy controls. A majority of these probes was under the control of Th2 cytokines, as evidenced by parallel experiments performed on primary cultures of nasal epithelial cells. In uncontrolled asthmatic patients, we observed not only an enhanced expression of these Th2-responsive transcripts, but also a down-regulation of interferon-responsive genes. Conclusion: Our study identifies a Th2 driven epithelial phenotype common to all dust mite allergic children. Besides, it suggests that epithelium is involved in the severity of the disease. Expression profiles observed in uncontrolled asthmatic patients suggest that severity of asthma is linked at the same time to atopy and to impaired viral response. Nasal epithelium gene expression profiling of dust mite allergic children with isolated rhinitis, rhinitis associated with asthma and controls. 38 samples classified in 4 categories : 14 isolated rhinitis (R), 6 rhinitis with uncontrolled asthma (UA), 7 rhinitis with controlled asthma (CA) and 11 healthy subjects (C )
Project description:This study investigated temporal transcriptomic changes in response to nasal allergen challenge of titrated timothy grass pollen. This is an open single-center observational study conducted outside the pollen season. Twelve participants with seasonal allergic rhinitis underwent a control (diluent) challenge followed by nasal allergen challenge after an interval of 14 days. On each challenge day, nasal challenge with control or titrated timothy grass pollen (Aquagen, phleum pratense; ALK) was administered. Peripheral blood was collected before nasal challenge (baseline) and at 3, 6 and 24 hours following challenge. RNA was extracted from whole blood and CD4 cells for microarray experiment using Affymetrix Human Gene 1.0 ST arrays.
Project description:Seasonal allergic rhinitis (SAR) is a complex disease that is caused by many interacting genes and environmental factors. It is also an excellent model disease for clinical studies; it is common, it is seasonal, and since it takes place in the nasal cavity it can be studied in vivo non-invasively. Furthermore, the key disease cell, the Th2 cell is known. We study SAR using allergen-challenged CD4+ cells from allergic patients.
Project description:The link between upper and lower airways in patients with both asthma and allergic rhinitis is still poorly understood. As the biological complexity of these disorders can be captured by gene expression profiling we hypothesized that the clinical expression of rhinitis and/or asthma is related to differential gene expression between upper and lower airways epithelium. We used micro array to profile gene expression of primary nasal and bronchial epithelial cells from the same individuals and examining the impact of allergic rhinitis with and without concomitant allergic asthma on expression profiles.