AA-T3A-C12 is a leading anisamide-tethered lipidoid (AA-lipidoid) identified through a combinatorial library screening for targeted RNA delivery to activated fibroblasts, offering a promising approach to treat liver fibrosis.AA-T3A-C12 is a leading anisamide-tethered lipidoid (AA-lipidoid) identified through a combinatorial library screening for targeted RNA delivery to activated fibroblasts, offering a promising approach to treat liver fibrosis. It is synthesized via a one-pot, two-step modular method that combines anisamide—a ligand for sigma receptors overexpressed on activated hepatic stellate cells (HSCs)—with a T3A polyamine core and C12 epoxide tails, enabling efficient siRNA encapsulation in lipid nanoparticles (LNPs).
In vitro, AA-T3A-C12 LNPs exhibit enhanced cellular uptake and gene silencing in activated fibroblasts, dependent on sigma receptor binding, as confirmed by haloperidol blockade studies, and outperform non-targeted analogs and the FDA-approved MC3 LNPs in fibroblast selectivity.In a mouse model of CCl4-induced liver fibrosis, AA-T3A-C12/siHSP47 LNP achieves approximately 65% knockdown of heat shock protein 47 (HSP47), a key fibrotic target, leading to significant reduction in collagen deposition and fibrosis alleviation, with a good safety profile and no exacerbation of liver injury.