PDCD1 and neoplasm: De Aquino et al. further characterize this immunosuppressive network, comprised of tumor-associated macrophages (TAMs), DCs, MDSCs, Tregs, inhibitory molecules (such as TGF-β, FasL, and IL-10), and immune checkpoint signals, such as CTLA4 and the PD-1/PD-1L interaction [130].