title: Thiolated trimethyl chitosan nanocomplexes as gene carriers with high in vitro and in vivo transfection efficiency.
abstract: Trimethyl chitosan-cysteine conjugate (TMC-Cys) was evaluated as non-viral gene carriers to combine the advantages of TMC and thiolated chitosan. TMC-Cys with various molecular weights (30, 100, and 200 kDa) and quaternization degrees (15 and 30%) was allowed to form polyelectrolyte nanocomplexes with plasmid encoding enhanced green fluorescence protein (pEGFP), which demonstrated preferable diameters of below 200 nm and zeta potentials of +15 to +20 mV. Cell binding and uptake of TMC-Cys/pEGFP nanocomplexes (TMC-Cys NC) were enhanced 2.4-3.0 and 1.4-3.0 folds, respectively, compared to TMC/pEGFP nanocomplexes (TMC NC). pEGFP could be easily released from TMC-Cys NC at the intracellular glutathione concentration, which promoted its nuclear transport and accumulation. Consequently, TMC-Cys NC showed a 1.4 to 3.2-fold increase in the transfection efficiency in HEK293 cells as compared to TMC NC and the optimal TMC-Cys(100,30) NC showed a 1.5-fold enhancement than Lipofectamine2000. Such results were further confirmed by in vivo transfection with a 2.3-fold and 4.1-fold higher transfection efficiency of TMC-Cys(100,30) NC than TMC(100,30) NC and Lipofectamine2000, respectively. Therefore, TMC-Cys/DNA nanocomplexes could be a promising gene delivery system with in vitro and in vivo superiority to Lipofectamine2000.
authors.affiliation: State Key Laboratory of Genetic Engineering, Department of Pharmaceutical Sciences, School of Life Sciences, Fudan University, Shanghai 200433, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.forename: Lichen
authors.initials: L
authors.lastname: Yin
authors.forename: Jieying
authors.initials: J
authors.lastname: Ding
authors.forename: Cui
authors.initials: C
authors.lastname: Tang
authors.forename: Shaohua
authors.initials: S
authors.lastname: Gu
authors.forename: Chunhua
authors.initials: C
authors.lastname: Yin
authors.forename: Yumin
authors.initials: Y
authors.lastname: Mao
mesh_terms: D001692:Biological Transport; D001693:Biological Transport, Active; D048271:Chitosan / Q000737:chemistry*; D004247:DNA; D018014:Gene Transfer Techniques; D005796:Genes; D049452:Green Fluorescent Proteins; D006801:Humans; D008970:Molecular Weight; D010957:Plasmids; D014162:Transfection / Q000379:methods*
chemical_list: C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D004247:DNA; D048271:Chitosan