Donor lung Prevotella predicts favorable early FEV1 trajectory following lung transplantation

The lung microbiome is implicated in graft function, rejection, and other outcomes following lung transplantation. Lung dysbiosis is highly prevalent in lung transplant recipients likely due to widespread antimicrobial use, immunosuppression, and impaired mucociliary defenses and cough reflexes. We performed pre- (donor) and post-transplant (recipient) assessments of LRT microbiota in 35 lung allografts. We profiled LRT microbiota with 16S rRNA gene sequencing of genomic DNA from 164 bronchoalveolar lavage fluid (BALF) samples, 35 obtained from donor lungs prior to transplantation and 129 obtained longitudinally post-transplantation following bronchoscopies done for clinical care, with a median of 5 BALF samples per study participant (range 2-8), Our study has two major findings. First, the transplanted allograft's microbiota composition rapidly shifts away from the donor profile early after transplant and remains distinct. Second, donor lung microbiome dominated by Prevotella was associated with improved FEV1 trajectory post-transplantation after controlling for indication and other covariates, suggesting that Prevotella abundance may be a biomarker of a healthier donor lung.