Figure 1.

ARG1 expression is highly upregulated in human glioblastomas and murine experimental gliomas. (A) ARG1 expression in gliomas of different WHO grades (WHO grades II- IV) in TCGA datasets. Statistical significance was determined by Tukey’s Honest Significant Difference (HSD). ***p < 0.001. (B) Expression of ARG1 in malignant cells and microglia/macrophages (MG/MΦ) in 10 samples of astrocytomas in single-cell RNA-seq datasets (public data) from (33). (C) UMAP plot of CD11b⁺ cells from GL261 gliomas (n=8). Projection of cells combined from clusters identified as microglia, monocytes/macrophages (Mo/MΦ), and BAMs. Plots depicting Arg1 mRNA which is highly expressed in infiltrating Mo/MΦ. (D) Flow cytometry analysis of Arg1 expressing cells among microglia (CD11b⁺CD45^lo) and Mo/MΦ (CD11b⁺CD45^high) cells sorted from murine gliomas (n=10); Wilcoxon matched-pairs signed rank, two-tailed, **p < 0.01.