Extensive transcriptional and ontogenetic diversity exists among normal tissue-resident
macrophages, with unique transcriptional profiles endowing the cells with tissue-specific
functions. However, it is unknown whether the origins of different macrophage populations
affect their roles in malignancy. Given potential artifacts associated with irradiation-based
lineage tracing, it remains unclear if bone-marrow-derived macrophages (BMDMs) are
present in tumors of the brain, a tissue with no homeostatic involvement of BMDMs. Here, we …