Drug binding to α_IIbβ₃ and induction of MIBS and LIBS. (A) Eptifibatide or tirofiban binds to α_IIb/β_3, as indicated. Drug binding (eptifibatide in panel B or tirofiban in panel C) induces emergence of drug-specific MIBS (mimetic-induced binding site) and nonspecific LIBS (ligand-induced binding site). Drug-dependent antibodies recognize and bind MIBS and not LIBS.