Biochem/physiol Actions
High-affinity FKBP12 F36V mutant cross-linker for Chemical Induction of Dimerization (CID) of Chimeric Antigen Receptor (CAR) in vitro and in vivo.
Rimiducid (AP1903) is a homodimeric FKBP12 Phe36Val (F36V-FKBP, FKBP-F36V) mutant-selective cross-linker composed of two high-affinity ligands, each with 713-fold selectivity over endogenous FKBP (Kd = 94 pM/F36V- vs 67 nM/Wt-FKBP using 4′-AF-labeled rimiducid). Rimiducid activates signaling events via Chemical Induction of Dimerization (CID) by cross-linking FKBP12-F36 fusions (Chimeric Antigen Receptor or CAR) expressed in cells in cultures (apoptosis induction EC50 = 0.1 nM; HT1080 expressing FKBP(F36V)-Fas intracellular domain) and in animals in vivo (EC50 = 0.4 mg/kg i.v. in a murine model of conditional cell ablation).