AX6 is an ionizable lipid in the F32 LNP formulation, engineered by ReNAgade/Orna Therapeutics for targeted mRNA delivery to T cells. AX-6's unique bridged bicyclic/polycyclic core with a tertiary amine group enables pH-dependent protonation and endosomal escape, while C14-C18 hydrophobic tails (optionally branched/fluorinated) enhance bilayer stability and mRNA encapsulation. Demonstrating exceptional T-cell tropism, AX6 achieves high transfection efficiency in CD4+/CD8+ T cells (validated in NHP/humanized models) with minimal toxicity. Compared to clinical benchmarks (SM-102, ALC-0315), its rigid core offers superior serum stability and immune-cell specificity, positioning it as an ideal candidate for CAR-T/NK therapies and next-gen vaccines. The F32 LNP system's proven efficacy (e.g., in vivo B-cell depletion) underscores AX 6's transformative potential for cell engineering and immunotherapies.
