PRJNA518155
Oropharyngeal dysbiosis in advanced lung disease and following lung transplantation
The oropharyngeal microbiome is a primary source of lung microbiota and a driver of oral health. We, therefore, sought to understand oropharyngeal microbial dynamics in advanced lung disease and lung transplantation. Oropharyngeal wash (OW) samples were obtained from individuals with end-stage disease awaiting transplantation (n=22), longitudinally from individuals at 6-weeks, 3-months and 6-months following transplantation (n=33), and healthy controls (n=14). Bacterial 16S and fungal ITS rRNA regions were deep-sequenced, and bacterial respiratory patterns were imputed from a taxonomic composition. Healthy subjects' oropharyngeal microbiomes showed a gradient of community types reflecting relative enrichment of strictly anaerobic, aerobic or facultative anaerobic bacteria. Pre- and post-transplant groups showed dysbiosis by both taxonomic composition and imputed respiration phenotypes. Pre-transplant subjects had severely reduced richness and diversity, increased facultative and decreased aerobic bacteria, and absence of communities characterized by obligate aerobes. Early post-transplant, richness, and diversity were less aberrant, with a near-normal distribution of community types, but by six months OW resembled the low-diversity facultative-dominated profile of pre-transplant subjects. Community ecotype correlated with Candida abundance. Thus, end-stage lung disease is associated with marked upper respiratory tract dysbiosis, which persists post-transplantation. Aberrant oropharyngeal communities may contribute to abnormal lung microbiota both in advanced lung disease and after transplantation.