Journal: Nature Communications
Article Title: Pulmonary fibroblast activation during Aspergillus fumigatus infection enhances lung defense via immunomodulation and tissue remodeling
doi: 10.1038/s41467-026-71027-5
Figure Lengend Snippet: A Schematic of the TAM-inducible DTA ablation model. The Cre recombinase, inserted into the Postn locus, is controlled by a TAM-inducible estrogen receptor ( MerCreMer ). Upon Postn promoter activation, TAM-induced recombination of the DTA gene results in DTA toxin expression from the rosa26 locus, preventing fibroblast activation and expansion. B Schematic representation of the experimental approach: Mice were inoculated OP with 1 × 10 6 conidia, followed by immunosuppression with triamcinolone acetonide 5 h post-infection. TAM was administered via gavage one day before fungal inoculation and maintained through a TAM-infused chewing diet for the duration of the experiment. C Percent survival of immunosuppressed mice infected with A. fumigatus ( n = 24 for control group and n = 20 for DTA group; p = 3.8 × 10 −5 , log rank test). D Gross appearance of lungs from infected DTA and control mice on day 4 post-infection. E Representative histopathologic images showing focal alveolar hemorrhage and angioinvasion in the A. fumigatus -infected DTA mice by H&E and GMS staining, respectively. F Distribution of alveolar hemorrhage severity in control (white bars) and DTA mice (red bars). Alveolar hemorrhage was scored semi quantitatively as described in Fig. . Data are shown as box-and-whisker plots with individual biological replicates overlaid ( n = 10 for control group and n = 8 for DTA group). Boxes represent the interquartile range (IQR), horizontal lines indicate the median, and whiskers extend to 1.5 x IQR (two-tailed Mann–Whitney U test). G Quantification of angioinvasion in intrapulmonary arteries of control (white bars) and DTA (red bars) mice. The percentage of vessels ≥100 µm in diameter that contained A. fumigatus hyphae in each animal were quantified in GMS-stained lung sections. Values represent the mean ± SD from 10 and 8 biological replicates in the control and DTA groups, respectively, with individual replicates indicated by dots (unpaired two-tailed t -test). H Collagen deposition quantified from Picrosirius Red-stained sections of lung tissue. Values represent the mean ± SD from 10 and 8 biological replicates in the control (white bars) and DTA (red bars) groups, respectively, with individual replicates indicated by dots (ns, no significant; unpaired two-tailed t -test) ( I ) Schematic representation of the experimental approach: similar to the schematic shown in ( B ), but lung tissue was harvested at day 4 post-challenge for further analysis, coinciding with the highest mortality rate observed in ( C ). J Flow cytometric quantification of viable Pdgfrα + cells. Right panels show the cell gating strategy used to distinguish viable and dead cells within the Pdgfrα + population. Values represent the mean ± SD from 5 and 8 biological replicates in the control and DTA groups, respectively ( p = 3.5 × 10 −5 ; unpaired two-tailed t -test). K Fungal burden quantification by RT-qPCR from lung lobes of the indicated mouse models. Fungal burden is expressed as Genome Equivalents (GE) per mg of lung tissue. Values represent the mean ± SD from 5 and 8 biological replicates in the control (white bars) and DTA (red bars) groups, respectively, with individual replicates indicated by dots ( p < 0.05; unpaired two-tailed t -test). L Quantification of immune infiltration by flow cytometry. Total leukocytes and hematopoietic subsets were discriminated using the antibodies indicated on the y -axis. Values represent the mean ± SD from 5 and 8 biological replicates in the control and DTA groups, respectively, with individual replicates indicated by dots (ns, no significant, unpaired two-tailed t-test). Source data are provided as a Source Data file.
Article Snippet: Rosa26-tdTomato (B6.Cg- Gt(rosa)26Sor tm14(CAG-tdTomato)Hze /J; JAX Strain #:007914), Rosa26-DTA (B6.129S6(Cg)- Gt(ROSA))26Sor tm1(DTAJpmb /J; JAX Strain #:032087), Pdgfrα-CreERT2 (B6.129S- Pdgfra tm1.1(cre/ERT2)Blh /J; JAX Strain #:032770), and Pdgfrα-eGFP (B6.129S4- Pdgfra tm11(EGFP)Sor /J; JAX Strain #:007669) mice were purchased from The Jackson Laboratory.
Techniques: Activation Assay, Expressing, Infection, Control, Staining, Whisker Assay, Two Tailed Test, MANN-WHITNEY, Quantitative RT-PCR, Flow Cytometry
