CART- a transfection delivery system for efficient intracellular mRNA delivery

Stanford researchers have developed a new class of materials that enable new strategies for the efficient delivery of messenger RNA (mRNA) into cells and animals. The delivery materials are easily prepared (2 steps), stable and readily tuned. Upon simple mixing, they form non-covalent complexes with mRNA that protect, deliver and release mRNAs of varied lengths. While mRNA therapeutics have the potential to transform disease treatment, their large size, polyanionic nature and susceptibility to degradation by nucleases make delivering mRNA across tissues and into cells a formidable challenge. Clinical utility is hampered by the lack of safe and effective delivery methods. Thus new delivery systems are needed to allow the intracellular delivery of mRNA in vitro and in vivo. To address this need the inventors developed a new, tunable, effective class of synthetic biodegradable materials called charge-altering releasable transporters (CARTs). CARTs operate through an unprecedented mechanism, serving initially to non-covalently complex, protect and deliver the mRNA and then change their physical properties through a degradative charge-neutralizing intramolecular rearrangement to release the mRNA in cells. This technology provides a tool for effective mRNA delivery that results in functional protein expression both in cells and animals. It can also be extended to other RNAs and has shown efficacy with plasmid DNA with up to 10,000 negative charges.

Stage of research
CART transfection efficiency was tested in vitro using multiple cell lines, including hard to transfect J774 cells. CARTs showed significantly better transfection efficiencies than commercial reagents; achieving greater than 98% transfection. Animal (mouse) studies showed mRNA expression is highly effective in vivo via multiple (IM, IV, SC) routes of administration.