Blood and Nasal Epigenetics Correlate to Allergic Rhinitis Symptom Development in the Environmental Exposure Unit
ABSTRACT: 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. Overall design: This cohort consist of genomic DNA extracted from lymphocyte-enriched blood samples from 15 Atopic and 8 non atopic participants. DNA was bisulphite converted and hybridized to the Illumina Infinium HumanMethylation450 Beadchip for genome wide DNA methylation profiling.
Project description:We profiled genome-wide gene expression in nasal scrapes following grass pollen challenge and Prednisone treatment. It was a randomized, double-blind, placebo-controlled, three-period, cross-over trial to evaluate the effects of single oral doses of 10 mg and 25 mg of prednisone on inflammatory mediators measured in nasal exudates after nasal allergen challenge in susceptible individuals with allergic rhinitis. It examined the ability to quantify responses to allergen challenge and resolve dose responsive treatment effects of prednisone. Overall design: This was a randomized, double-blind, placebo-controlled, three treatment period crossover study in 19 healthy patients with allergic rhinitis and allergy to grass pollen. Allergen was rapidly delivered using a nasal mist delivery system. Period 0 was a baseline in the absence of allergen challenge.
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:A Randomized, Placebo-Controlled Trial of Intradermal Allergen Immunotherapy for Grass Pollen Allergy Background: Repeated intradermal injection of grass pollen (nanograms of allergen) suppresses allergen-induced cutaneous late phase responses, in keeping with effects of conventional high dose subcutaneous and sublingual immunotherapy. We evaluated the efficacy and safety of grass pollen intradermal immunotherapy for treatment of allergic rhinitis.Methods: We randomly assigned 93 adults with grass pollen allergic rhinitis to receive 7 pre-seasonal Intradermal allergen immunotherapy injections (containing 7 ng of Phl p 5 major allergen) or histamine control. The primary end point was daily combined symptom-medication scores during the 2013 pollen season. Skin biopsies were taken after the pollen season following an intradermal allergen challenge. Cutaneous late phase responses were measured 4 and either 7, 10 or 13 months post-treatment. Results No difference in the primary endpoint was observed between treatment arms (median difference, 14; 95% confidence interval [CI], -172.5 to 215.1; P=0.80). Amongst secondary endpoints, nasal symptoms measured with daily scores (median difference, 35; 95% CI, 4.0 to 67.5; P=0.03) and visual-analogue scales (median difference, 53; 95% CI, -11.6 to 125.2; P=0.05) were higher in the intradermal treatment group. Intradermal immunotherapy increased serum Phl p-specific IgE (P=0.001) compared to the control arm and T cells cultured from biopsies showed higher and lower surface of surface markers for Type 2 (P=0.04) and Type 1 (P=0.01) T-helper cells, respectively, Interleukin-5 was differentially expressed by microarray (P=0.03). Late phase responses were still inhibited 7 months after treatment (P=0.03) but not at 10-13 months. Conclusions Grass pollen intradermal allergen immunotherapy was not clinically effective but resulted in immunological priming and worsening of allergic rhinitis symptoms. Overall design: T-cells were isolated from skin biopsy by explant culture from control subjects (8) and subjects undergoing IDIT (7). After 7 days T-cells were activated with PMA/Ionomycin. Control subjects were compared with IDIT subjects.
Project description:Timothy grass (TG) pollen is a common seasonal airborne allergen associated with symptoms ranging from mild rhinitis to severe asthma. The aim of this study was to characterize changes in TG-specific T cell responses as a function of seasonality. Peripheral blood mononuclear cells (PBMC) obtained either during the pollen season or out of season, from allergic individuals and non-allergic controls were stimulated either with TG extract or a pool of previously identified immunodominant antigenic regions. PBMC from in season allergic subjects exhibit higher IL-5 and IL-10 responses compared to out of season donors. In the case of non-allergic subjects, as expected we observed lower IL-5 responses and robust production of IFNγ compared to allergic individuals. Strikingly, non-atopic donors exhibited an opposing pattern with decreased immune reactivity in-season. The broad downregulation in non-allergic donors indicates that healthy individuals are not oblivious to allergen exposure but rather react with an active modulation of the responses following the antigenic stimulus provided during the pollen season. Transcriptomic analysis of allergen-specific T cells defined genes modulated in concomitance with allergen exposure and inhibition of responses in non-allergic donors. Magnitude and functionality of T-helper cell responses differ substantially for in season versus out of season in allergic and non-allergic subjects. The results indicate specific and opposing modulation of immune responses following the antigenic stimulation during the pollen season. This seasonal modulation reflects the enactment of specific molecular programs associated with health and allergic disease. Overall design: 11 allergen-specific T cell RNA samples were analyzed: 5 isolated from PBMC of allergic individuals and 6 from non-allergic individuals (considered as the control group).
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:Gene expression (Npatients = 21, Ncontrols = 21) of CD4+ T-cells failed to seperate patients with seasonal allergic rhinitis (SAR) and healthy controls in an in vitro model system in which purified PBMCs from patients and healthy controls were challenged with allergen for 7 days. PBMCs from 21 patients (P) and 21 healthy controls (H) were challenged with grass pollen for 7 days. Diluent challenged control samples were obtained from all subjects. CD4+ cells were purified by MACS.
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. Overall design: 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: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: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. Overall design: 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: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).