Single-cell RNA sequencing reveals immunosuppressive myeloid cell diversity during malignant progression in a murine model of glioma

Cell Rep. 2023 Mar 28;42(3):112197. doi: 10.1016/j.celrep.2023.112197. Epub 2023 Mar 3.

Abstract

Recent studies have shown the importance of the dynamic tumor microenvironment (TME) in high-grade gliomas (HGGs). In particular, myeloid cells are known to mediate immunosuppression in glioma; however, it is still unclear if myeloid cells play a role in low-grade glioma (LGG) malignant progression. Here, we investigate the cellular heterogeneity of the TME using single-cell RNA sequencing in a murine glioma model that recapitulates the malignant progression of LGG to HGG. LGGs show increased infiltrating CD4+ and CD8+ T cells and natural killer (NK) cells in the TME, whereas HGGs abrogate this infiltration. Our study identifies distinct macrophage clusters in the TME that show an immune-activated phenotype in LGG but then evolve to an immunosuppressive state in HGG. We identify CD74 and macrophage migration inhibition factor (MIF) as potential targets for these distinct macrophage populations. Targeting these intra-tumoral macrophages in the LGG stage may attenuate their immunosuppressive properties and impair malignant progression.

Keywords: CD74; CP: Cancer; CP: Neuroscience; MHCII; glioblastoma; immunosuppressive TME; low-grade glioma; malignant progression; myeloid cells; single-cell RNA sequencing.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Brain Neoplasms* / genetics
  • Brain Neoplasms* / pathology
  • CD8-Positive T-Lymphocytes / pathology
  • Disease Models, Animal
  • Glioma* / genetics
  • Glioma* / pathology
  • Macrophages / pathology
  • Mice
  • Sequence Analysis, RNA
  • Tumor Microenvironment