Fig. 2: Transplanted human airway basal progenitors re-epithelialized the injured mouse lung.

a Direct fluorescence image of mouse lung transplanted with human GFP-labeled human airway basal progenitor cells showing engraftment, captured under a stereomicroscope. Scale bar, 1 mm. b Immunofluorescence images of engrafted human cells in mouse lung with human-specific antibodies anti-HuLamin (red) immunostaining. Nuclei counterstain, DAPI (blue). Scale bar, 1 mm. c IHC staining of engrafted cells (brown) in mouse lung 8 (left) or 35 days (right) post-transplantation (dpt) with anti-GFP antibodies. Scale bar, 1 mm. Enlarged inset: high magnification views of the representative pod and saccular structures. Scale bar, 100 μm. d Mean linear intercept (MLI) of native human (hAlveoli) and murine alveoli (mAlveoli) as well as human saccules (Sac) (n = 13, 6, 23 technical replicates from 3 biological replicates). Data are presented as mean ± SEM. e Wall thickness of native human (hAlveoli) and murine alveoli (mAlveoli) as well as human saccules (Sac) (n = 50, 50, 275 technical replicates from 3 biological replicates). Data are presented as mean ± SEM. f 3D visualization showing the connection of human pods and saccules(sac) with mouse airway. 3D reconstruction was performed based on anti-GFP IHC stained serial sections of mouse lungs, which were transplanted with human airway basal progenitor cells and analyzed on 8 dpt (left) or 35 dpt (right), respectively. g Schematic diagram showing the process of lung respiratory tract growth and saccule formation from mouse airway. h H&E staining (left) and anti-GFP IHC staining (right) of engrafted human cells on a lung tissue section for spatial transcriptomic analysis. Green circle: saccule zone, blue circle: pod zone. Scale bar, 300 μm. i Spatial visualization of human cells in lung section which was noted using human reference genome (GRCh38) by spatial transcriptomic analysis. Scale bar, 1 mm. j Spatial visualization of various gene expression in lung sections by spatial transcriptomic analysis. Green circle: saccule zone, blue circle: pod zone. Scale bar, 300 μm.