Project description:The goal of this investigation was to establish proof of concept that nasal epithelium can be used as a proxy for the airway epithelium in studies of allergic asthma. We collected PBMCs, nasal epithelia, and bronchial epithelia from 12 subjects with allergic asthma and 12 control subjects without asthma, all non-Hispanic white nonsmoker adults. We conclude that genomic profiling of nasal epithelia captures most disease-relevant changes identified in airway epithelia but also provides additional targets that are most likely influenced by exposures. Thus, epigenetic marks in nasal epithelia may prove useful as a biomarker of disease severity and response to treatment or as a biosensor of the environment in asthma.
Project description:The goal of this investigation was to establish proof of concept that nasal epithelium can be used as a proxy for the airway epithelium in studies of allergic asthma. We collected PBMCs, nasal epithelia, and bronchial epithelia from 12 subjects with allergic asthma and 12 control subjects without asthma, all non-Hispanic white nonsmoker adults. We conclude that genomic profiling of nasal epithelia captures most disease-relevant changes identified in airway epithelia but also provides additional targets that are most likely influenced by exposures. Thus, epigenetic marks in nasal epithelia may prove useful as a biomarker of disease severity and response to treatment or as a biosensor of the environment in asthma.
Project description:Background: Nasal epithelia are emerging as a proxy measure of gene expression of the airway epithelium in asthma. We hypothesized that epigenetic marks regulate gene expression of the nasal epithelia and consequently may provide a novel target for allergic asthma. Methods: We compared genomic DNA methylation patterns and gene expression in African American children with persistent atopic asthma [N=36] versus healthy controls [N=36]. Results were validated in an independent population of asthmatics [N=30]. Results: We identified 186 genes with significant methylation changes, either as regions (differentially methylated regions [DMRs]) or single CpGs (differentially methylated probes [DMPs]) after adjustment for age, gender, race/ethnicity, batch effects, inflation, and multiple comparisons (false discovery rate-adjusted q<0.05). Genes differentially methylated include those with established roles in asthma and atopy, components of the extracellular matrix, genes related to immunity, cell adhesion, epigenetic regulation, and airway obstruction. The methylation changes are large (median 9.5%, range: 2.6-29.5% methylation change) and similar in magnitude to those observed in malignancies. Hypo- and hyper-methylated genes were associated with increased and decreased gene expression respectively (P<2.8x10-6 for DMRs and P<7.8x10-10 for DMPs). Quantitative analysis of methylation-expression relationships in 53 differentially expressed genes demonstrated that 32 (60%) have significant (q<0.05) methylation-expression relationships within 5kb of the gene. 10 loci selected based on the relevance to asthma, magnitude of methylation change, and asthma specific methylation-expression relationships were validated in an independent cohort of children with asthma. Conclusions: Our findings that epigenetic marks in respiratory epithelia are associated with allergic asthma in inner-city children provide new targets for biomarker development, and novel approaches to understanding disease pathogenesis. case control design with nasal epithelial cells from 36 atopic asthmatic and 36 nonatopic nonasthmatic children from the inner city
Project description:Background: Nasal epithelia are emerging as a proxy measure of gene expression of the airway epithelium in asthma. We hypothesized that epigenetic marks regulate gene expression of the nasal epithelia and consequently may provide a novel target for allergic asthma. Methods: We compared genomic DNA methylation patterns and gene expression in African American children with persistent atopic asthma [N=36] versus healthy controls [N=36]. Results were validated in an independent population of asthmatics [N=30]. Results: We identified 186 genes with significant methylation changes, either as regions (differentially methylated regions [DMRs]) or single CpGs (differentially methylated probes [DMPs]) after adjustment for age, gender, race/ethnicity, batch effects, inflation, and multiple comparisons (false discovery rate-adjusted q<0.05). Genes differentially methylated include those with established roles in asthma and atopy, components of the extracellular matrix, genes related to immunity, cell adhesion, epigenetic regulation, and airway obstruction. The methylation changes are large (median 9.5%, range: 2.6-29.5% methylation change) and similar in magnitude to those observed in malignancies. Hypo- and hyper-methylated genes were associated with increased and decreased gene expression respectively (P<2.8x10-6 for DMRs and P<7.8x10-10 for DMPs). Quantitative analysis of methylation-expression relationships in 53 differentially expressed genes demonstrated that 32 (60%) have significant (q<0.05) methylation-expression relationships within 5kb of the gene. 10 loci selected based on the relevance to asthma, magnitude of methylation change, and asthma specific methylation-expression relationships were validated in an independent cohort of children with asthma. Conclusions: Our findings that epigenetic marks in respiratory epithelia are associated with allergic asthma in inner-city children provide new targets for biomarker development, and novel approaches to understanding disease pathogenesis.
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:Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by persistent symptoms associated to the development of nasal polyps. To this day, the molecular mechanisms involved are still not well defined. However, it has been suggested that a sustained inflammation as allergy is involved in its onset. In this pilot study, we aimed to look into the effect of the allergic status of the patient and in their underlying mechanisms. To achieve this, we recruited 22 patients with CRSwNP and classified them in non-allergic and allergic using ImmunoCAP ISAC molecular diagnosis. Plasma samples were analyzed using liquid chromatography coupled to mass spectrometry (LC-MS). Subsequently, the identified changed metabolites from plasma that were commercially available were then analyzed by targeted analysis in some nasal polyps. Additionally, nasal polyp and mucosa tissue samples were examined for eosinophils and neutrophils. We found that 9 out of the 22 patients were sensitized to some aeroallergens (named as allergic). The other 13 patients had no sensitizations (non-allergic). Regarding metabolomics, we found that bilirubin, cortisol, lysophosphatidylcholines (LPCs) 16:0, 18:0 and 20:4 and lysophosphatidylinositol (LPI) 20:4, metabolites that are usually related to a sustained allergic inflammation, were unexpectedly increased in the plasma of non-allergic patients with CRSwNP compared to allergic patients with CRSwNP. LPC 16:0, LPC 18:0 and LPI 20:4 metabolites followed the same trend in the nasal polyp as they did in plasma. Comparison of nasal polyps with nasal mucosa tissue showed a significant increase in eosinophils (p < 0.001) and neutrophils (p < 0.01) in allergic patients with CRSwNP. There were also more eosinophils in the polyps of non-allergic patients with CRSwNP than in their nasal mucosa (p <0.01). The polyps from non-allergic patients with CRSwNP had less eosinophils than the polyps of allergic patients with CRSwNP (p < 0.05). Our data suggests that there is a systemic inflammatory response associated to CRSwNP in the absence of allergy, which could be accountable for the nasal polyp development. Allergic patients with CRSwNP presented a higher number of eosinophils located in nasal polyps suggesting that eosinophilia might be connected to the development of nasal polyps in these patients.
Project description:Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by persistent symptoms associated to the development of nasal polyps. To this day, the molecular mechanisms involved are still not well defined. However, it has been suggested that a sustained inflammation as allergy is involved in its onset. In this pilot study, we aimed to look into the effect of the allergic status of the patient and in their underlying mechanisms. To achieve this, we recruited 22 patients with CRSwNP and classified them in non-allergic and allergic using ImmunoCAP ISAC molecular diagnosis. Plasma samples were analyzed using liquid chromatography coupled to mass spectrometry (LC-MS). Subsequently, the identified changed metabolites from plasma that were commercially available were then analyzed by targeted analysis in some nasal polyps. Additionally, nasal polyp and mucosa tissue samples were examined for eosinophils and neutrophils. We found that 9 out of the 22 patients were sensitized to some aeroallergens (named as allergic). The other 13 patients had no sensitizations (non-allergic). Regarding metabolomics, we found that bilirubin, cortisol, lysophosphatidylcholines (LPCs) 16:0, 18:0 and 20:4 and lysophosphatidylinositol (LPI) 20:4, metabolites that are usually related to a sustained allergic inflammation, were unexpectedly increased in the plasma of non-allergic patients with CRSwNP compared to allergic patients with CRSwNP. LPC 16:0, LPC 18:0 and LPI 20:4 metabolites followed the same trend in the nasal polyp as they did in plasma. Comparison of nasal polyps with nasal mucosa tissue showed a significant increase in eosinophils (p < 0.001) and neutrophils (p < 0.01) in allergic patients with CRSwNP. There were also more eosinophils in the polyps of non-allergic patients with CRSwNP than in their nasal mucosa (p <0.01). The polyps from non-allergic patients with CRSwNP had less eosinophils than the polyps of allergic patients with CRSwNP (p < 0.05). Our data suggests that there is a systemic inflammatory response associated to CRSwNP in the absence of allergy, which could be accountable for the nasal polyp development. Allergic patients with CRSwNP presented a higher number of eosinophils located in nasal polyps suggesting that eosinophilia might be connected to the development of nasal polyps in these patients.