Fig. 4

Additive fecal microbiota transfer from Facility B to A renders the recipients more susceptible to the lung injury response. A, B Littermate progenies of the conventionalized ex-GF founders that were born and raised in each SPF facility were separated into two cages. One cage of mice received the pooled fecal slurry from themselves (A → A or B → B), and another cage of mice received the pooled fecal slurry from mice housed in a different facility (A → B or B → A), via 3 oral gavages in a week. 10-days after the first dose of gavage, the mice were challenged with 1 U/kg of intratracheal bleomycin. Weight curves showing the effect of fecal microbiota transfer from the Facility B to A (A), and from the Facility A to B (B). Overall, around 70% of the mice from all groups survived with no statistically significant difference, and datapoints were censored upon death. P-values were obtained from the mixed-effects analysis of the data and depicted as P < 0.001 (***) or non-significant (ns). C–E Fecal samples collected from FMT recipients at before and after gavaging were sequenced for 16S rRNA genes (V4–V5 region). C The within-sample richness and evenness (alpha diversity) were measured by Shannon index. Four groups are A: samples collected from Facility A mice prior to FMT (n = 7), B → A: samples collected from Facility A mice at 10 days after the first dose of Facility B microbiota transplant (n = 7), B: samples collected from Facility B mice prior to FMT (n = 6), A → B: samples collected from Facility B mice at 10 days after the first dose of Facility A microbiota transplant (n = 6). D Unweighted UniFrac analysis of similarity coefficients were calculated from 16S rRNA gene sequences of each mouse. E Heatmap of the percent sequence amplicons measured from a list of commensal taxa that were present in donor mice in Facility B but absent in recipient mice in Facility A at baseline. Fecal samples from donor mice were pooled and sampled on days of gavage treatment. Fecal samples from 7 recipient mice were collected longitudinally at baseline, 10-days after the first dose of gavage (FMT), and 7-days after bleomycin challenge (FMT + BLM). F, G Shallow shotgun metagenomics analysis of fecal samples from progenies of the conventionalized ex-GF founder mice in the two facilities. The samples were collected from naïve mice without any treatment. Total 268 unique taxa were identified using k-mer based classification on One Codex databse (Transnetyx). F Venn diagram showing the taxa that were exclusively present in each facility. G Read counts for species within Helicobacter and Desulfovibrio genera in 10 mice sampled for metagenomic sequencing analysis