ARG1 and neoplasm: More recently, the αGM-CSF antibody was found to reprogram the tumor microenvironment from immunosuppressive to anti-tumorigenic in intrahepatic cholangiocarcinoma by reducing the expression of ARG1 and PD-L1 in granulocytes and monocytes, inhibiting M2 TAMs, and augmenting activation and tumor-infiltration of CD8+ T cells, leading to a pan-myeloid repolarization towards the pro-immunogenic, anti-tumor phenotype (182).