Helper-Polymer Based Five-Element Nanoparticles (FNPs) for Lung-Specific mRNA Delivery with Long-Term Stability after Lyophilization

Abstract

Lipid nanoparticles (LNPs) carrying therapeutic mRNAs hold great promise in treating lung-associated diseases like viral infections, tumors, and genetic disorders. However, because of their thermodynamically unstable nature, traditional LNPs carrying mRNAs need to be stored at low temperatures, which hinders their prevalence. Herein, an efficient lung-specific mRNA delivery platform named five-element nanoparticles (FNPs) is developed in which helper-polymer poly(β-amino esters) (PBAEs) and DOTAP are used in combination. The new strategy endows FNPs with high stability by increasing the charge repulsion between nanoparticles and the binding force of the aliphatic chains within the nanoparticles. The structure−activity relationship (SAR) shows that PBAEs with E1 end-caps, higher degrees of polymerization, and longer alkyl side chains exhibit higher hit rates. Lyophilized FNP formulations can be stably stored at 4 °C for at least 6 months. Overall, a novel delivery platform with high efficiency, specificity, and stability was developed for advancing mRNA-based therapies for lung-associated diseases.

Lipid Nanoparticle (LNP) Enables mRNA Delivery for Cancer Therapy

“…[112] Third, Cao et al developed PBAEbased five-element nanoparticles (FNPs), which are composed of optimized PBAE, DOPE, cholesterol, DMG-PEG, and DOTAP, and could effectively deliver mRNA into the lungs. [113] The mechanism studies suggested that lung targeting was dependent on vitronectin binding on the surface of FNPs, which is consistent with the SORT mechanisms reported before. [108] In addition to the lipid compositions of LNP, the N/P (N referring to amine groups of ionizable cationic lipids and P referring to phosphate groups of mRNA) molar ratio also has a great influence on the properties of LNP.…”

“…developed PBAE‐based five‐element nanoparticles (FNPs), which are composed of optimized PBAE, DOPE, cholesterol, DMG‐PEG, and DOTAP, and could effectively deliver mRNA into the lungs. [ 113 ] The mechanism studies suggested that lung targeting was dependent on vitronectin binding on the surface of FNPs, which is consistent with the SORT mechanisms reported before. [ 108 ]…”

Exploration of mRNA nanoparticles based on DOTAP through optimization of the helper lipids

“…[ 56 ] Furthermore, some researchers have elaborated on the SORT strategy, demonstrating that incorporating the fifth component into positively charged LNPs can facilitate the successful delivery of mRNA to the lung. [ 12,26 ] Similarly, Q. Cheng, T et al. performed an experiment of the SORT in mice based on the charge of the lipid.…”

“…[10] Recently, LNPs based on DOTAP have been used in preclinical and clinical settings widely. [3,[11][12][13][14][15] For example, an efficient lung-specific mRNA delivery platform known as five-element nanoparticles (FNPs) has been developed by combining PBAEs and DOTAP. [12] Furthermore, the paclitaxel-encapsulated cationic liposomal delivery system named EndoTAG-1, which is based on DOTAP, has recently entered a phase III clinical trials.…”

Optimal delivery strategies for nanoparticle-mediated mRNA delivery

“…18 Interestingly, protein corona enriched with Vtn has the potential for endogenous targeting of alpha-v-beta-3 (αvβ3) enriched organs or tissues (such as lungs and tumors). 40,41 The β2-GPI binding to phosphatidylserine enables LNPs to target the spleen. 42 The protein corona enriched with different specific proteins is determined mainly by regulating the physiochemical properties of LNPs.…”