Elliot A Philips, Jia Liu, Audun Kvalvaag, Alexander M Mørch, Anna S Tocheva, Charles Ng, Hong Liang, Ian M Ahearn, Ruimin Pan, Christina C Luo, Alexander Leithner, Zhihua Qin, Yong Zhou, Antonio Garcia-España, Adam Mor, Dan R Littman, Michael L Dustin, Jun Wang, Xiang-Peng Kong
Programmed cell death-1 (PD-1) is a potent immune checkpoint receptor on T lymphocytes. Upon engagement by its ligands, PD-L1 or PD-L2, PD-1 inhibits T cell activation and can promote immune tolerance. Antagonism of PD-1 signaling has proven effective in cancer immunotherapy, and conversely, agonists of the receptor may have a role in treating autoimmune disease. Some immune receptors function as dimers, but PD-1 has been considered monomeric. Here, we show that PD-1 and its ligands form dimers as a consequence of transmembrane domain interactions and that propensity for dimerization correlates with the ability of PD-1 to inhibit immune responses, antitumor immunity, cytotoxic T cell function, and autoimmune tissue destruction...
March 8, 2024: Science Immunology