IL2 and neoplasm: Delivery of an antitumor cytokine payload demonstrated feasibility in PDAC mice treated with single-domain antibodies against PD-L1 fused with IFNγ or IL-2 in vivo; reduced tumor burden seen from targeting IFNγ was associated with decreased numbers of CD11b+ cells and transition of intratumoral macrophages towards an M1-like phenotype [38].