Fig. 9: The local and distal microbiota contribute to the IDO1/AhR axis in the lung.
From: Bridging of host-microbiota tryptophan partitioning by the serotonin pathway in fungal pneumonia
a Cytoscape network of lung and gut microbiome that qualitatively contributes to Indole (red), Kynurenine (purple), and 5-HT (cyan) pathways. Taxa identified by Q2- ALDEx2 as driving the difference between Tph1–/– and Tph1+/+ and contributing with an effect size versus Tph1–/– littermates at dpi 7 were used to create networks. Each hexagon represents a bacterial sequence variant, each dot represents an enzyme in a pathway, according to the dot label. Taxa are grouped by genus, explicitly shown in the figure, and colored by phylum (Actinobacteriota, darkcyan; Bacteroidota, salmon1; Firmicutes, palegreen; Verrucomicrobiota, honeydew; Proteobacteria, tan; Campilobacterota, darkgrey). Edges show the qualitative contribution (presence) of each taxon to enzymes, and all have the same width. b Description of tryptophan catabolic pathways in lung (blue arrows) and feces (brown arrows) of Tph1–/– mice. c–g A. fumigatus-infected Tph1+/+ and Tph1–/– mice were transplanted with fresh lung homogenates or fecal pellets from uninfected Tph1+/+ or Tph1–/– mice as depicted in the experimental schedule (c). Mice were sacrificed at 4 days post infection and assessed for d fungal burden, e % neutrophils and monocytes in the bronco-alveolar lavage, f lung histology (periodic acid-Schiff staining) and g gene expression in the lungs (RT-PCR). Photographs were taken with a high-resolution microscope (Olympus BX51), ×10 magnification (scale bar 500 µm). Data are expressed as mean ± SEM and representative from two experiments. *p < 0.05, **p < 0.01, and ***p < 0.001, LMT or FMT vs untreated (None) mice. The in vivo groups consisted of three mice/group. LMT, lung microbiota transplantation. FMT, fecal microbiota transplantation. One-way ANOVA, Dunnett post hoc test. Adjusted P values for d: 0.0354 (Tph1+/+, None vs LMT), 0.0068 (Tph1–/–, None vs LMT), 0.0083 (Tph1–/–, None vs FMT); for e: 0.0495 (Neutrophils (%), Tph1+/+, None vs FMT), 0.0008 (Neutrophils (%), Tph1–/–, None vs LMT), 0.0054 (Neutrophils (%), Tph1–/–, None vs FMT), 0.0084 (Monocytes (%), Tph1+/+, None vs LMT), 0.0033 (Monocytes (%), Tph1–/–, None vs LMT), 0.0025 (Monocytes (%), Tph1–/–, None vs FMT); for g: 0.0368 (Haao, Tph1–/–, None vs LMT), 0.0074 (Kmo, Tph1–/–, None vs LMT), 0.0248 (Cyp1a1, Tph1–/–, None vs LMT), 0.0301 (Cyp1b1, Tph1–/–, None vs LMT). Source Data are provided as a Source Data file.
