Fig. 1

a Bacterial 16S gene copies/ml in allograft (A), native (N) of single lung transplant recipients and normal (H) lung controls. The Y axis indicates 16S rRNA gene copy number by quantitative PCR. (N vs A vs H, P = 0.02 (Kruskal Wallis), post-hoc Dunn’s test, N vs A = 0.1, N vs H = NS, A vs H = 0.04,) (b) Shannon diversity index in allograft (A), native (N) of single lung transplant recipients and normal (H) lung controls. N vs A vs H, P = 0.06 (Kruskal Wallis), post-hoc Dunn’s test, N vs A = NS, N vs H = NS, A vs H=NS (c) Relationship between native and transplant airway bacterial communities within individual subjects. Weighted UniFrac distances were calculated between all pairs of samples within native or allograft, and then each sample type was plotted separately in 3D space by principal coordinate analysis. The two plots (allograft and transplant) were then transformed by Procrustes analysis to achieve maximum alignment. Each point corresponds to a bacterial community, with native communities shown in red, allograft communities shown in blue, and the two communities from each subject connected by a bar. The black end of each bar connects to the native sample data; the grey end connects to the allograft lung sample data from the same individual. If native and allograft plots are similar, then the relative distance between connected points (residuals) will be small. The overall similarity is summarized by the M² value, and statistical goodness of fit is measured by a Monte Carlo label permutation approach (10,000 iterations). The M² value ranges from 0 to 1, with 0 suggesting complete overlap i.e. similarity and 1 suggesting maximum variation. M² = 0.715 suggests a greater degree of variation between the native and allograft microbiome from individual patients. d Principal coordinate analyses (PCoA): ordination constrained by specimen group (RDA) showing spatial relationship of the variance between allograft (A) and native (N) of single lung transplant recipient microbiomes. Native are shown in red and allograft in blue. P value calculated via PERMANOVA analysis N vs A, P = 0.05. e Principal coordinate analyses (PCoA): ordination constrained by specimen group (RDA) showing spatial relationship of the variance between allograft (A) and normal (H) lung microbiomes. Normal lung controls are shown in green and allograft in blue. P value calculated via PERMANOVA analysis A vs H, P = 0.0009 (f) Principal coordinate analyses (PCoA): ordination constrained by specimen group (RDA) showing spatial relationship of the variance between native (N) lung of single lung transplant recipients and normal (H) lung control microbiomes. Normal lung controls are shown in green and native in red. P value calculated via PERMANOVA analysis N vs H, P = 0.003