Mechanisms regulating PD-L1 expression on tumor and immune cells

The PD-1/PD-L1 checkpoint is a central mediator of immunosuppression in the tumor immune microenvironment (TME) and is primarily associated with IFN-g signaling. To characterize other factors regulating PD-L1 expression on tumor and/or immune cells, we investigated TME-resident cytokines and the role of transcription factors in constitutive and cytokine-induced PD-L1 expression.