Can form trans-heterodimers with PVRL3/nectin-3 (By similarity). Interacts with CD226. Binds with low affinity to TIGIT. Interacts with herpes simplex virus 1 (HHV-1) mutant Rid1, herpes simplex virus 1 (HHV-2) and pseudorabies virus (PRV) envelope glycoprotein D; functions as an entry receptor for these viruses.