PVR (Poliovirus Receptor): PVR is a transmembrane glycoprotein that functions as a receptor for poliovirus and related enteroviruses, facilitating viral entry and infection. Beyond its role in viral recognition, PVR is essential for cell-cell adhesion, immune regulation, and tissue homeostasis. It contributes to the integrity of epithelial and endothelial barriers through its involvement in adherens and tight junctions. Interactions of PVR with ligands such as TIGIT and DNAM-1 help regulate immune cell activation, influencing both innate and adaptive immune responses. Dysregulation of PVR expression or function can have significant impacts on immune function and tissue integrity.