(A) UMAP clustering from 21 pediatric brain samples (13 PAs, 5 HGGs, and 3 NBs). (B) The frequency of CAFs is a function of glioma grade. Data represent mean ± SEM. **P < 0.01. LGG, low-grade glioma. (C) Stacked histogram of CAF subtypes by glioma grade. Color within the bar denotes the CAF subtype. (D) Bubble plot depicting gene ontology (GO) analysis of functions that are suppressed by CAFs. Each bubble represents a GO term, the bubble size corresponds to the gene ratio, and the color indicates the P value. (E) Dot plot displaying collagen and receptor expression within pediatric gliomas. Bubble size corresponds to the percentage of cells expressing gene marker; colors indicate average expression. (F) Multiplex imaging demonstrates PDGFRA⁺VIM⁺PDGFRB⁺ACTA2⁺ CAFs embedded in COL6A1/A2 (white) within HGG. Scale bar: 50 μm. See Supplemental Video 1. (G) ACTA2⁺COL4A⁺ arteries were embedded in a COL1A1/A2 matrix infiltrated with immune cells. Scale bar: 50 μm. (H) LAIR1⁺ myeloid cells embedded in COL6A1/A2⁺ areas. Scale bar: 50 μm. (I) Quantification of LAIR1⁺ cells in COL6A1/A2⁺ areas versus areas without COL6A1/A2 in HGG (n = 3 samples and 5 ROI per sample). Data represent mean ± SEM.