Indeed, in a recent study by Noguchi and colleagues, IFN-γ was responsible for up regulating PD-L1 in tumor cells, contributing to immune escape, but unexpectedly, the majority of PD-L1 molecules were expressed by the host immune system, especially in the macrophage compartment, suggesting a mechanism in trans to impair T cells function. The gene discussed is IFNG; the disease is neoplasm.