Investigations of the Microbial Communities of the Respiratory Tract in the Elderly and in Cystic Fibrosis via Culture-Dependent and -Independent Approaches
| Autor: | Whelan, Fiona Jane |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Druh dokumentu: | Diplomová práce |
| Popis: | The human microbiota is the collection of microorganisms which live on and in the human body. These organisms have been implicated in a host of diseases and disorders and nationwide initiatives have helped us understand their heterogeneity across the population in health. In this work, I investigate the respiratory tract microbiota and its correlations in age and disease. Elderly (≥ 65 years of age) are at a greater risk of respiratory infection; previous studies have shown changes to the elderly gut microbiota which correlate with the health of these individuals. Thus, we investigated the upper respiratory tract in comparison to mid-aged adults to identify statistically different communities within the anterior nares and oropharynx which may be associated with increased respiratory infection risk in this population. Individuals with cystic fibrosis have a lung microbiota which contributes to the onset of pulmonary exacerbations, increased inflammation, which is the greatest cause of patient mortality. However, it is not understood what triggers these events. In this work, we used 16S rRNA gene sequencing to longitudinally identify the lung microbiota in a subset of patients but were unable to identify any consistent correlations in the lung microbiota and pulmonary exacerbation onset. In order to gain a better resolution of these communities, we combined culture-independent sequencing technology with culture-enrichment. We showed that 81.21% of OTUs representing 99.15% of the biomass of the cystic fibrosis lung is culturable and that metagenomic sequencing of these cultured communities provide better taxonomic resolution of the cystic fibrosis lung. Together, this work shows the contributions of the respiratory tract microbiota in age and disease. Thesis Doctor of Philosophy (PhD) The microbes that live on and in us affect our health and can cause disease. Within, I investigate the association of these microbes in the airways. First, we show that the microbes in the noses and throats of the elderly differ from adults. We hypothesize that these differences may be associated with the increased incidence of respiratory infections, such as pneumonia and influenza, in this population. Second, we study the microorganisms that inhabit the lungs of individuals with cystic fibrosis. The bacteria of the lungs are the main cause of disease. In our study, we attempt to identify why these patients go through cycles of extreme sickness and hospitalization, but we were unable to find a cause of this in the microbiota. A follow up study using new techniques provided us with a better resolution of these communities which will help us better understand cystic fibrosis. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|