A biocleavable pullulan-based vector via ATRP for liver cell-targeting gene delivery.
Pullulan due to its specificity for liver has been widely exploited for biomedical applications. In this work, a tailor-made biocleavable pullulan-based gene vector (PuPGEA) with good hemocompatibility was successfully proposed via atom transfer radical polymerization (ATRP) for efficient liver cell-targeting gene delivery. A two-step method involving the reaction of hydroxyl groups of pullulan with cystamine was developed to introduce reduction-sensitive disulfide-linked initiation sites of ATRP onto pullulan. The poly(glycidyl methacrylate) (PGMA) side chains prepared subsequently via ATRP were functionalized with ethanolamine (EA) to produce the resultant biocleavable comb-shaped PuPGEA vectors consisting of nonionic pullulan backbones and disulfide-linked cationic EA-functionalized PGMA (PGEA) side chains with plentiful secondary amine and nonionic hydroxyl units. The cationic PGEA side chains can be readily cleavable from the pullulan backbones of PuPGEA under reducible conditions. Due to the liver targeting performance of pullulan backbones, such PuPGEA vectors exhibited much higher gene transfection efficiency and cellular uptake rates in HepG2 cell lines than in Hella cell lines. In addition, in vitro transfection efficiency and uptake mechanism of polyplex in HepG2 cells were evaluated in the presence of different endocytosis inhibitors, indicating that the asialoglycoprotein receptor was involved in transfection process of hepatocytes. More importantly, in comparison with gold standard polyethylenimine (PEI, ∼25 kDa), PuPGEA vectors possessed excellent hemocompatibility without causing undesirable hemolysis. Properly grafting short bioreducible PGEA polycation side chains from a liver cell-targeting pullulan backbone is an effective means to produce new hemocompatible polysaccharide-based gene delivery vectors.
State Key Laboratory of Chemical Resource Engineering, Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing Laboratory of Biomedical Materials, College of Materials Science & Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Xin-Chao
XC
Yang
Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210046, China.
Yan-Lan
YL
Niu
State Key Laboratory of Chemical Resource Engineering, Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing Laboratory of Biomedical Materials, College of Materials Science & Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
Na-Na
NN
Zhao
Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210046, China.
Chun
C
Mao
State Key Laboratory of Chemical Resource Engineering, Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing Laboratory of Biomedical Materials, College of Materials Science & Engineering, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address: fujian_xu@yahoo.com.
Fu-Jian
FJ
Xu
D004705:Endocytosis / Q000187:drug effects; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D005936:Glucans / Q000737:chemistry*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D008099:Liver
D005936:Glucans; C009109:pullulan
Bioreducible vector; Gene delivery; Hemocompatibility; PGEA; Pullulan