title: Reestablishment of recipient-associated microbiota in the lung allograft is linked to reduced risk of bronchiolitis obliterans syndrome.
abstract: BACKGROUND
  Bronchiolitis obliterans syndrome (BOS) is the primary limiting factor for long-term survival after lung transplantation, and has previously been associated with microbial infections.
  
  
  OBJECTIVE
  To cross-sectionally and longitudinally characterize microbial communities in allografts from transplant recipients with and without BOS using a culture-independent method based on high-throughput sequencing.
  
  
  METHODS
  Allografts were sampled by bronchoalveolar lavage, and microbial communities were profiled using 16S rRNA gene amplicon pyrosequencing. Community profiles were compared using the weighted Unifrac metric and the relationship between microbial populations, BOS, and other covariates was explored using PERMANOVA and logistic regression.
  
  
  RESULTS
  Microbial communities in transplant patients fell into two main groups: those dominated by Pseudomonas or those dominated by Streptococcus and Veillonella, which seem to be mutually exclusive lung microbiomes. Aspergillus culture was also negatively correlated with the Pseudomonas-dominated group. The reestablishment of dominant populations present in patients pretransplant, notably Pseudomonas in individuals with cystic fibrosis, was negatively correlated with BOS.
  
  
  CONCLUSIONS
  Recolonization of the allograft by Pseudomonas in individuals with cystic fibrosis is not associated with BOS. In general, reestablishment of pretransplant lung populations in the allograft seems to have a protective effect against BOS, whereas de novo acquisition of microbial populations often belonging to the same genera may increase the risk of BOS.
authors: Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, QLD, Australia. d.willner@uq.edu.au.
authors: Dana L
authors: DL
authors: Willner
authors: Philip
authors: P
authors: Hugenholtz
authors: Stephanie T
authors: ST
authors: Yerkovich
authors: Maxine E
authors: ME
authors: Tan
authors: Joshua N
authors: JN
authors: Daly
authors: Nancy
authors: N
authors: Lachner
authors: Peter M
authors: PM
authors: Hopkins
authors: Daniel C
authors: DC
authors: Chambers
mesh_terms: D000328:Adult; D001232:Aspergillus fumigatus / Q000302:isolation & purification; D001989:Bronchiolitis Obliterans / Q000453:epidemiology* / Q000382:microbiology* / Q000517:prevention & control; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology; D003550:Cystic Fibrosis / Q000382:microbiology; D004269:DNA, Bacterial / Q000032:analysis; D005260:Female; D006801:Humans; D008168:Lung / Q000382:microbiology*; D016040:Lung Transplantation / Q000009:adverse effects*; D008297:Male; D054892:Metagenome; D008875:Middle Aged; D025341:Principal Component Analysis; D011549:Pseudomonas / Q000302:isolation & purification; D018570:Risk Assessment; D012307:Risk Factors; D013291:Streptococcus / Q000302:isolation & purification; D013577:Syndrome; D014184:Transplantation, Homologous; D014678:Veillonella / Q000302:isolation & purification
chemical_list: D004269:DNA, Bacterial