Polysarcosine-based lipid formulations for intracranial delivery of mRNA

Dongdong Bi; Dennis Mark Unthan; Lili Hu; Jeroen Bussmann; Katrien Remaut; Matthias Barz; Heyang Zhang

doi:10.1016/j.jconrel.2023.02.021

Polysarcosine-based lipid formulations for intracranial delivery of mRNA

J Control Release. 2023 Apr:356:1-13. doi: 10.1016/j.jconrel.2023.02.021. Epub 2023 Feb 28.

Authors

Dongdong Bi¹, Dennis Mark Unthan¹, Lili Hu¹, Jeroen Bussmann¹, Katrien Remaut², Matthias Barz³, Heyang Zhang⁴

Affiliations

¹ Leiden Academic Centre for Drug Research (LACDR), Leiden University, Einsteinweg 55, 2333, CC, Leiden, the Netherlands.
² Laboratory for General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
³ Leiden Academic Centre for Drug Research (LACDR), Leiden University, Einsteinweg 55, 2333, CC, Leiden, the Netherlands; Department of Dermatology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany. Electronic address: m.barz@lacdr.leidenuniv.nl.
⁴ Leiden Academic Centre for Drug Research (LACDR), Leiden University, Einsteinweg 55, 2333, CC, Leiden, the Netherlands. Electronic address: h.zhang@lacdr.leidenuniv.nl.

PMID: 36803765
DOI: 10.1016/j.jconrel.2023.02.021

Abstract

Messenger RNA (mRNA) is revolutionizing the future of therapeutics in a variety of diseases, including neurological disorders. Lipid formulations have shown to be an effective platform technology for mRNA delivery and are the basis for the approved mRNA vaccines. In many of these lipid formulations, polyethylene glycol (PEG)-functionalized lipid provides steric stabilization and thus plays a key role in improving the stability both ex vivo and in vivo. However, immune responses towards PEGylated lipids may compromise the use of those lipids in some applications (e.g., induction of antigen specific tolerance), or within sensitive tissues (e.g., central nervous system (CNS)). With respect to this issue, polysarcosine (pSar)-based lipopolymers were investigated as an alternative to PEG-lipid in mRNA lipoplexes for controlled intracerebral protein expression in this study. Four polysarcosine-lipids with defined sarcosine average molecular weight (M_n = 2 k, 5 k) and anchor diacyl chain length (m = 14, 18) were synthesized, and incorporated into cationic liposomes. We found that the content, pSar chain length and carbon tail lengths of pSar-lipids govern the transfection efficiency and biodistribution. Increasing carbon diacyl chain length of pSar-lipid led up to 4- and 6-fold lower protein expression in vitro. When the length of either pSar chain or lipid carbon tail increased, the transfection efficiency decreased while the circulation time was prolonged. mRNA lipoplexes containing 2.5% C14-pSar2k resulted in the highest mRNA translation in the brain of zebrafish embryos through intraventricular injection, while C18-pSar2k-liposomes showed a comparable circulation with DSPE-PEG2k-liposomes after systemic administration. To conclude, pSar-lipid enable efficient mRNA delivery, and can substitute PEG-lipids in lipid formulations for controlled protein expression within the CNS.

Keywords: Lipid formulations; Polysarcosine; Zebrafish embryo; mRNA intracerebral delivery.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Lipids
Liposomes*
Polyethylene Glycols
RNA, Messenger
Sarcosine*
Tissue Distribution
Transfection
Zebrafish

Substances

polysarcosine
Liposomes
Sarcosine
RNA, Messenger
Polyethylene Glycols
Lipids