Fig. 6.

Differential metabolic fingerprints identified by DESI-MSI and UMAP segmentation confirmed immune infiltration by single-section multimodal imaging workflow. a Whole section H&E stain of a kidney tissue post-DESI scanning. b DESI-MS ion image of m/z 175.0247 (ascorbic acid) and c corresponding UMAP segmentation cluster of the MSI data. Detailed view of one of the areas with a higher concentration of ascorbic acid by d H&E showing fibrotic scars and immune cell infiltration; e mIHC labelling with pan-cytokeratin (PK, cyan labelling) and vimentin (brown labelling) expression indicating increased numbers of mesenchymal cells (fibroblasts) contributing to fibrosis and f composite image of mIF labelling of CD8⁺ (green) and CD45⁺ (red) cells. g, h Identified CD45⁺ and CD8⁺ cells through the application of HALO® AI image analysis to the mIF data. Section analyzed with HTL at 450 °C