Rationally Engineering Pro-Proteins and Membrane-Penetrating α‑Helical Polypeptides for Genome Editing Toward Choroidal Neovascularization Treatment.

Abstract

Ribonucleoprotein (RNP)-based CRISPR/Cas9 genome editing holds great potential for the treatment of choroidal neovascularization (CNV), which however, is challenged by the lack of efficient cytosolic protein delivery tools. Herein, reversibly-phosphorylated pro-proteins (P-proteins) with conjugated adenosine triphosphate (ATP) tags are engineered and coupled with a membrane-penetrating, guanidine-enriched, α-helical polypeptide (_LGP) to mediate robust and universal cytosolic delivery. _LGP forms salt-stable nanocomplexes (NCs) with P-proteins via electrostatic interaction and salt bridging, and the helix-assisted, strong membrane activities of _LGP enabled efficient cellular internalization and endolysosomal escape of NCs. Therefore, this approach allows efficient cytosolic delivery of a wide range of protein cargoes and maintains their bioactivities due to endolysosomal acidity-triggered traceless restoration of P-proteins. Notably, intravitreally delivered _LGP/P-RNP NCs targeting hypoxia-inducible factor-1α (HIF-1α) induce pronounced gene disruption to downregulate pro-angiogenic factors and alleviate subretinal fibrosis, ultimately provoking robust therapeutic efficacy in CNV mice. Such a facile and versatile platform provides a powerful tool for cytosolic protein delivery and genome editing, and it holds promising potential for the treatment of CNV-associated diseases, such as age-related macular degeneration.