Spatial distribution of microbial communities in the cystic fibrosis lung

Department of Biology, San Diego State University, San Diego, CA, USA.
The ISME Journal (Impact Factor: 9.3). 07/2011; 6(2):471-4. DOI: 10.1038/ismej.2011.104
Source: PubMed


Cystic fibrosis (CF) is a common fatal genetic disorder with mortality most often resulting from microbial infections of the lungs. Culture-independent studies of CF-associated microbial communities have indicated that microbial diversity in the CF airways is much higher than suggested by culturing alone. However, these studies have relied on indirect methods to sample the CF lung such as expectorated sputum and bronchoalveolar lavage (BAL). Here, we characterize the diversity of microbial communities in tissue sections from anatomically distinct regions of the CF lung using barcoded 16S amplicon pyrosequencing. Microbial communities differed significantly between different areas of the lungs, and few taxa were common to microbial communities in all anatomical regions surveyed. Our results indicate that CF lung infections are not only polymicrobial, but also spatially heterogeneous suggesting that treatment regimes tailored to dominant populations in sputum or BAL samples may be ineffective against infections in some areas of the lung.

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    • "While past selection in different environments could explain this difference, considerable variation in resistance exists also among clinical P. aeruginosa strains (Essoh et al., 2013; Friman et al., 2013). This variability could be explained by different sources of initial infection (Burns et al., 2001), gene loss due to within-host adaptation (Folkesson et al., 2012; Rau et al., 2012), cross-infection from other patients in CF-treatment centres (Jelsbak et al., 2007), prior exposure to phages through aerosol transmission (Ojeniyi et al., 1991; Willner et al., 2012a), or by chance events due to clinical interventions or interactions with surrounding microbial community (Mowat et al., 2011; Hansen et al., 2012; Willner et al., 2012b). Therefore, phage treatments might need to be adjusted in a patient-specific manner according the matching host and parasite genotypes, or alternatively, phage cocktails with broader host range could be employed (Merabishvili et al., 2009; Hall et al., 2012). "
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    • "Indeed, reads of P. aeruginosa were obtained in all but one P. aeruginosa positive-sample from which P. aeruginosa was only detected using qPCR. The 13 predominant genera identified in the present study are commonly found in CF respiratory tract microbiota (Willner et al. 2012; Venkataraman et al. 2015; Tunney et al. 2008; Carmody et al. 2013). Nine of them have been described to be the most abundant genera in healthy lungs (Wat et al. 2008). "
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