Fig. 2. Lipid heterogeneity in mouse IRI kidneys.
a, Lipid heterogeneity in mouse sham kidneys (n = 3) from which mice were opened up and closed similarly as bIRI mice but no ligations were performed, visualized in a two-dimensional (2D) UMAP plot of MALDI-MSI data (20 × 20 µm2 pixel size). b, Lipid heterogeneity in mouse bIRI kidneys (n = 3), visualized in a 2D UMAP plot of MALDI-MSI data at 20 × 20 µm2 pixel size. The dot plot displays lipid expression of cluster-enriched signatures. Exp, expression. c, IF staining (LTL, green), E-cadherin (CDH1, red), and BS1-lectin (gray)) of tissue that had been analyzed with MALDI-MSI. Representative images showing lipid species distributions in sham (n = 3) and bIRI (n = 3) kidneys, as recorded by MALDI-MSI (20 × 20 μm2 pixel size). Scale bars, 500 µm. d, Molecular histology of sham (n = 3) and bIRI (n = 3) kidneys generated from integrated three-dimensional (3D) UMAP analysis on the basis of lipid profiles. The color code represents the position of pixels in the 3D UMAP (UMAP1: red, UMAP2: green, UMAP3: blue). Scale bar, 500 µm. e, Comparison of PT areas between sham (n = 3) and bIRI (n = 3) kidneys. Two-tailed t-test was performed. f, PAS staining showing the tubular structures in the outer stripe outer medulla area of sham (n = 3) and bIRI (n = 3) kidneys. Scale bars, 50 µm. PT-S1/S2, cortical proximal tubular segments 1 and 2; PT-S3, outer stripe of outer medulla proximal tubular segment; DT, distal tubule; CDLH, collecting duct and loop of Henle; IM, inner medulla; OSOM, outer stripe of outer medulla; ISOM, inner stripe of outer medulla; PUL, pelvic urothelial lining.