title: The transition from linear to highly branched poly(β-amino ester)s: Branching matters for gene delivery.
abstract: 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. However, to date, all research has been focused on vectors with a linear structure. A well-accepted view is that dendritic or branched polymers have greater potential as gene delivery vectors because of their three-dimensional structure and multiple terminal groups. Nevertheless, to date, the synthesis of dendritic or branched polymers has been proven to be a well-known challenge. We report the design and synthesis of highly branched poly(β-amino ester)s (HPAEs) via a one-pot "A2 + B3 + C2"-type Michael addition approach and evaluate their potential as gene delivery vectors. We find that the branched structure can significantly enhance the transfection efficiency of poly(β-amino ester)s: Up to an 8521-fold enhancement in transfection efficiency was observed across 12 cell types ranging from cell lines, primary cells, to stem cells, over their corresponding linear poly(β-amino ester)s (LPAEs) and the commercial transfection reagents polyethyleneimine, SuperFect, and Lipofectamine 2000. Moreover, we further demonstrate that HPAEs can correct genetic defects in vivo using a recessive dystrophic epidermolysis bullosa graft mouse model. Our findings prove that the A2 + B3 + C2 approach is highly generalizable and flexible for the design and synthesis of HPAEs, which cannot be achieved by the conventional polymerization approach; HPAEs are more efficient vectors in gene transfection than the corresponding LPAEs. This provides valuable insight into the development and applications of nonviral gene delivery and demonstrates great prospect for their translation to a clinical environment.
authors.affiliation: School of Materials and Engineering, Tianjin University, Tianjin 300072, China.; Charles Institute of Dermatology, School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland.
authors.forename: Dezhong
authors.initials: D
authors.lastname: Zhou
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland.
authors.forename: Lara
authors.initials: L
authors.lastname: Cutlar
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland.
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland.
authors.forename: Jonathan
authors.initials: J
authors.lastname: O'Keeffe-Ahern
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland.
authors.forename: Sean
authors.initials: S
authors.lastname: McMahon
authors.affiliation: Cutaneous Diseases Modelling Unit, Division of Biomedicine, Centro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT), Madrid 28040, Spain.
authors.forename: Blanca
authors.identifier: 0000-0002-2850-5348
authors.initials: B
authors.lastname: Duarte
authors.affiliation: Cutaneous Diseases Modelling Unit, Division of Biomedicine, Centro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT), Madrid 28040, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Larcher
authors.affiliation: School of Physics and Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin 4, Ireland.
authors.forename: Brian J
authors.identifier: 0000-0001-9419-2717
authors.initials: BJ
authors.lastname: Rodriguez
authors.affiliation: Charles Institute of Dermatology, School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland.
authors.forename: Udo
authors.initials: U
authors.lastname: Greiser
authors.affiliation: School of Materials and Engineering, Tianjin University, Tianjin 300072, China.; Charles Institute of Dermatology, School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland.
authors.forename: Wenxin
authors.initials: W
authors.lastname: Wang
mesh_terms: D000818:Animals; D002460:Cell Line; D004195:Disease Models, Animal; D016108:Epidermolysis Bullosa Dystrophica / Q000378:metabolism / Q000473:pathology; D018014:Gene Transfer Techniques; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D011108:Polymers / Q000737:chemistry*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000302:isolation & purification; D016038:Skin Transplantation; D014162:Transfection / Q000295:instrumentation / Q000379:methods*
chemical_list: D011108:Polymers; D011994:Recombinant Proteins; C507253:poly(beta-amino ester)
keywords: Gene delivery; RDEB; highly branched polymer; non-viral vector; poly(β-amino ester)