Abstract

Interferon-Related Secretome Plays a Vital Role in PD-L1 Expression in the Tumor Microenvironment after Direct Interaction between Immune Cells and Tumor Cells

Yuan-Qin Yang, Jonathan Howard DeLong and Kang-Jian Zhang

PD-L1, also known as CD274 or B7-H1, is a major immune checkpoint protein . The binding of PD-L1 to its receptor PD-1 induces an inhibitory signal that suppresses the immune response by several mechanisms such as inhibiting the proliferation of CD8+ T effector cells. This research has resulted in the development of promising clinical drugs such as anti-PD-1 antibodies including Keytruda (pembrolizumab, Merck), and Opdivo (nivolumab, BMS) as well as the anti-PD-L1 antibody Tecentriq (atezolizumab, Roche), and other peptides and small molecule inhibitors for cancer immunotherapy. However, the mechanism by which tumor cells expressing PD-L1 regulate the function of infiltrating immune cells within the tumor microenvironment is still not well understood.