The Development of Cell-Penetrating Peptides for Efficient and Selective In Vivo Expression of mRNA in Spleen Tissue

Abstract

mRNA-based therapeutics are presently one of the nucleic acid-based therapeutics with a high potential for extraordinary success as preventive vaccines. Current applications with mRNA therapeutics rely on lipid nanoparticle (LNP) mediated delivery of nucleic acids. In order to achieve the transition from preventive to therapeutic vaccines, there is a challenge of delivering the mRNA into non-hepatic tissues, especially into lymphoid tissues such as the spleen and lymph nodes. In this work, we characterize new cell-penetrating peptides NF424 and NF436 that exhibit preferential delivery of mRNA into the spleen after a single i.v. injection, without the use of any active targeting mechanisms. We show that between the spleen, liver, and the lungs, >95% of mRNA expression arises in the spleen tissue and the majority of expression occurs in the dendritic cells. The cell-penetrating peptides NF424 and NF436 represent promising candidates for cancer immunotherapeutic applications with tumor antigens.

Advancing mRNA Therapeutics: The Role and Future of Nanoparticle Delivery Systems

“…Porosk et al introduced new CPP variants, NF424 and NF436, which preferentially targeted mRNA delivery to the spleen following a single intravenous injection without requiring additional active targeting mechanisms. 109 3.5. Inorganic NPs.…”

“…Despite relatively slow progress in delivering mRNA in vivo, CPPs hold promise in overcoming the challenge of mRNA delivery to nonhepatic tissues, a constraint typically seen with LNPs, which predominantly accumulate in the liver. Porosk et al introduced new CPP variants, NF424 and NF436, which preferentially targeted mRNA delivery to the spleen following a single intravenous injection without requiring additional active targeting mechanisms …”

N‐terminal modification of an LAH4‐derived peptide increases mRNA delivery in the presence of serum

“…Therefore, the key to enabling the growth of this approach is the development of efficient vectors that complex, deliver and release mRNA into the cytosol. Most mRNA transfection systems are based on the use of lipid nanoparticles (LNPs) [8,9], although some recent publications also describe the use of cellpenetrating peptides (CPPs) as delivery vehicle for mRNA [10][11][12][13].…”

Human β-Defensin 23 as a Carrier for In Vitro and In Vivo Delivery of mRNA

“…Few studies reported CPP-mediated in vivo mRNA delivery [16]. For in vivo mRNA delivery studies, CPPs have been chemically modified or mainly utilized as a component of hybrid materials for carriers [17][18][19]. In addition, most of the previously employed CPPs for mRNA delivery have sequences derived from non-human organisms or modified from human protein sequences [13].…”