Non-viral delivery of CRISPR-Cas9 complexes for targeted gene editing via a polymer delivery system.

Recent advances in molecular biology have led to the CRISPR revolution, but the lack of an efficient and safe delivery system into cells and tissues continues to hinder clinical translation of CRISPR approaches. Polymeric vectors offer an attractive alternative to viruses as delivery vectors due to their large packaging capacity and safety profile. In this paper, we have demonstrated the potential use of a highly branched poly(β-amino ester) polymer, HPAE-EB, to enable genomic editing via CRISPRCas9-targeted genomic excision of exon 80 in the COL7A1 gene, through a dual-guide RNA sequence system.

Highly branched poly(β-amino ester) delivery of minicircle DNA for transfection of neurodegenerative disease related cells.

Current therapies for most neurodegenerative disorders are only symptomatic in nature and do not change the course of the disease. Gene therapy plays an important role in disease modifying therapeutic strategies. Herein, we have designed and optimized a series of highly branched poly(β-amino ester)s (HPAEs) containing biodegradable disulfide units in the HPAE backbone (HPAESS) and guanidine moieties (HPAESG) at the extremities.

Brushlike Cationic Polymers with Low Charge Density for Gene Delivery.

Using a combined synthesis approach comprising reversible addition-fragmentation transfer polymerization and ring opening reaction, a series of poly glycidyl methacrylate (polyGMA) polymers were designed and synthesized for gene delivery. These polymers characterized by low cationic charge respective to established gene delivery vectors such as PEI were studied to further elucidate the key structure-activity parameters that mediate efficient and biocompatible gene delivery. Compared to PEI, these brushlike polymers facilitated markedly improved safety and gene delivery efficiency.

A new developing class of gene delivery: messenger RNA-based therapeutics.

Gene therapy has long been held as having the potential to become a front line treatment for various genetic disorders. However, the direct delivery of nucleic acids to correct a genetic disorder has numerous limitations owing to the inability of naked nucleic acids (DNA and RNA) to traverse the cell membrane. Recently, messenger RNA (mRNA) based delivery has become a more attractive alternative to DNA due to the relatively easier transfection process, higher efficiency and safety profile.

Star Poly(β-amino esters) Obtained from the Combination of Linear Poly(β-amino esters) and Polyethylenimine.

Composed of a three-dimensional structure with a central core and multiple radiating linear "arms", star polymers represent a significant type of branched macromolecular architectures. Due to the spatially defined core-shell-periphery architecture, star polymers have demonstrated their superiority in a variety of biomedical applications such as drug/gene delivery, molecular imaging, antibacterial agents, and so on. In this paper, we report the successful synthesis of a new type of star-shape poly(β-amino esters) with low molecular weight PEI as core and linear PAE (LPAE) as arms.

Highly Branched poly(5-amino-1-pentanol-co-1,4-butanediol diacrylate) for High Performance Gene Transfection.

The top-performing linear poly(β-amino ester) (LPAE), poly(5-amino-1-pentanol-co-1,4-butanediol diacrylate) (C32), has demonstrated gene transfection efficiency comparable to viral-mediated gene delivery. Herein, we report the synthesis of a series of highly branched poly(5-amino-1-pentanol-co-1,4-butanediol diacrylate) (HC32) and explore how the branching structure influences the performance of C32 in gene transfection. HC32 were synthesized by an "A2 + B3 + C2" Michal addition strategy.

Thermo- and pH-Responsive, Coacervate-Forming Hyperbranched Poly(β-amino ester)s for Selective Cell Binding.

We report a new type of thermo- and pH-responsive, coacervate-forming highly degradable polymer-hyperbranched poly(β-amino esters) (HPAEs) and its selective cell binding behaviors. The HPAEs were synthesized from 5-amino-1-pentanol (S5) and trimethylolpropane ethoxylate triacrylate (TMPETA) via an A2+B3 type Michael addition. The existence of multiple hydrogen bond pairs as well as tertiary amines makes the S5-TMPETA polymers manifest temperature- and pH-dependent phase transition.

Development of Branched Poly(5-Amino-1-pentanol-co-1,4-butanediol Diacrylate) with High Gene Transfection Potency Across Diverse Cell Types.

One of the most significant challenges in the development of polymer materials for gene delivery is to understand how topological structure influences their transfection properties. Poly(5-amino-1-pentanol-co-1,4-butanediol diacrylate) (C32) has proven to be the top-performing gene delivery vector developed to date. Here, we report the development of branched poly(5-amino-1-pentanol-co-1,4-butanediol diacrylate) (HC32) as a novel gene vector and elucidate how the topological structure affects gene delivery properties.

Highly Branched Poly(β-amino esters) for Non-Viral Gene Delivery: High Transfection Efficiency and Low Toxicity Achieved by Increasing Molecular Weight.

A successful polymeric gene delivery vector is denoted by both transfection efficiency and biocompatibility. However, the existing vectors with combined high efficacy and minimal toxicity still fall short. The most widely used polyethylene imine (PEI), polyamidoamine (PAMAM) and poly(dimethylaminoethyl methacrylate) (PDMAEMA) suffer from the correlation: either too toxic or little effective.

The transition from linear to highly branched poly(β-amino ester)s: Branching matters for gene delivery.

Nonviral gene therapy holds great promise but has not delivered treatments for clinical application to date. Lack of safe and efficient gene delivery vectors is the major hurdle. Among nonviral gene delivery vectors, poly(β-amino ester)s are one of the most versatile candidates because of their wide monomer availability, high polymer flexibility, and superior gene transfection performance both in vitro and in vivo.

Multifunctional oligomer incorporation: a potent strategy to enhance the transfection activity of poly(l-lysine).

Natural polycations, such as poly(l-lysine) (PLL) and chitosan (CS), have inherent superiority as non-viral vectors due to their unparalleled biocompatibility and biodegradability. However, the application was constrained by poor transfection efficiency and safety concerns. Since previous modification strategies greatly weakened the inherent advantages of natural polycations, developing a strategy for functional group introduction with broad applicability to enhance the transfection efficiency of natural polycations without compromising their cationic properties is imperative.

Tailoring highly branched poly(β-amino ester)s: a synthetic platform for epidermal gene therapy.

Highly branched poly(β-amino ester)s (HPAEs) were designed and synthesised for safe and efficient gene delivery to human keratinocytes. HPAEs outperformed commercial transfection reagents: PEI and SuperFect®, for both transfection efficiency and biocompatibility. A 22 and 3.