PTPRC and glioma: In murine gliomas (i.e., GL261, CT-2A, 005 GSC, and KR158B), M-MDSCs characterized by lineage markers CD45+, CD11b+, Ly6Chi, and Ly6G– (19, 24, 25), are the predominant subset present in the TME, with little to no PMN-MDSC infiltration (26–28).