Tailoring Hyperbranched Poly(β‐amino ester) as a Robust and Universal Platform for Cytosolic Protein Delivery

Abstract

Cytosolic protein delivery is a prerequisite for protein‐based biotechnologies and therapeutics on intracellular targets. Polymers that can complex with proteins to form nano‐assemblies represent one of the most important categories of materials, because of the ease of nano‐fabrication, high protein loading efficiency, no need for purification, and maintenance of protein bioactivity. Stable protein encapsulation and efficient intracellular liberation are two critical yet opposite processes toward cytosolic delivery, and polymers that can resolve these two conflicting challenges are still lacking. Herein, hyperbranched poly(β‐amino ester) (HPAE) with backbone‐embedded phenylboronic acid (PBA) is developed to synchronize these two processes, wherein PBA enhanced protein encapsulation via nitrogen–boronate (N–B) coordination while triggered polymer degradation and protein release upon oxidation by H2O2 in cancer cells. Upon optimization of the branching degree, charge density, and PBA distribution, the best‐performing A2‐B3‐C2‐S2‐P2 is identified, which mediates robust delivery of various native proteins/peptides with distinct molecular weights (1.6–430 kDa) and isoelectric points (4.1–10.3) into cancer cells, including enzymes, toxins, antibodies, and CRISPR‐Cas9 ribonucleoproteins (RNPs). Moreover, A2‐B3‐C2‐S2‐P2 mediates effective cytosolic delivery of saporin both in vitro and in vivo to provoke remarkable anti‐tumor efficacy. Such a potent and universal platform holds transformative potentials for protein pharmaceuticals.

ROS-Responsive Selenopolypeptide Micelles: Preparation, Characterization, and Controlled Drug Release

“…The structures of micelles after oxidation were characterized by proton nuclear magnetic resonance ( 1 H NMR), circular dichroism (CD), and Fourier transform infrared (FT-IR) as described above. In addition, the ROS-responsive drug release profile from DOX-loaded PEG-PBnSec micelles was further studied according to the previous literature, − ,, and the details are described in the Supporting Information.…”

Cardiomyocyte-targeted anti-inflammatory nanotherapeutics against myocardial ischemia reperfusion (IR) injury

“…Normally, polycations with higher molecular weights (MWs) feature stronger siRNA condensation and intracellular delivery efficiencies. However, they will impede the cytosolic release of siRNA to compromise the transfection efficiency and induce MW-dependent long-term toxicity [31][32][33]. To address this dilemma, ROS-degradable polycations have been developed and utilized for delivering siRNA into inflamed cells that produce elevated levels of ROS [34][35][36][37].…”

Cationic polymer synergizing with a disulfide-containing enhancer achieved efficient nucleic acid and protein delivery

“…[16][17][18] Similarly, for protein drugs targeting intracellularly and vaccine antigens, their large molecular weight does not allow them to directly penetrate the cell membrane, thus limiting their utilization efficiency. [19][20][21] Therefore, the development of high-performance delivery systems is crucial for the efficient utilization of nucleic acid drugs as well as protein drugs.…”