ARG1 and central nervous system cancer: Antitumor immune responses in aPD-1- and RGD + aPD-1-treated gliomas evolved with time, as at an earlier time point 21 DPI, the tumor volume did not change upon treatment (Fig. S7A-B), and the myeloid compartment was dominated by Arg1+ and PD-L1+ immunosuppressive macrophages (Fig. S7C-D).