Disease-associated microglia adopt stage-specific phenotypes that regulate T cell fate and immunity in glioma

Malignant gliomas are lethal brain tumors characterized by profound local immunosuppression and a radically remodeled myeloid landscape. Although these tumors mobilize resident microglia and infiltrating monocyte-derived macrophages, the mechanisms governing their phenotypic convergence and diversification remain elusive. Here, we integrated single-cell profiling and spatial transcriptomics of glioma-associated microglia in the GL261 model. We identified distinct microglial states that aligned with tumor architecture, most notably Cst7-expressing disease-associated microglia (DAMs) that aggregated at the tumor invasive margin and exhibited a conserved transcriptional signature shared across various central nervous system pathologies. Interferon-γ and toll-like receptor signaling sequentially tuned stage-specific DAM features, including transient MHC-II expression and sustained PD-L1 upregulation, thereby recalibrating the local immune equilibrium by reshaping bidirectional DAM-T cell interactions during glioma progression. Our findings highlight microglial state transitions as a stage-specific layer of immune regulation in glioma that shapes T cell fate and support targeting microglial plasticity to rebalance anti-tumor immunity.