Open AccessTrehalose-Based Block Copolycations Promote Polyplex Stabilization for Lyophilization and in Vivo pDNA Delivery
Author(s) -
Zachary P. Tolstyka,
Haley Phillips,
Mallory A. Cortez,
Yaoying Wu,
Nilesh P. Ingle,
Jason B. Bell,
Perry B. Hackett,
Theresa M. Reineke
Publication year - 2015
Publication title -
acs biomaterials science and engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.082
H-Index - 50
ISSN - 2373-9878
DOI - 10.1021/acsbiomaterials.5b00312
Subject(s) - trehalose , gene delivery , chemistry , transfection , biochemistry , hek 293 cells , biophysics , microbiology and biotechnology , biology , gene
The development and thorough characterization of nonviral delivery agents for nucleic acid and genome editing therapies are of high interest to the field of nanomedicine. Indeed, this vehicle class offers the ability to tune chemical architecture/biological activity and readily package nucleic acids of various sizes and morphologies for a variety of applications. Herein, we present the synthesis and characterization of a class of trehalose-based block copolycations designed to stabilize polyplex formulations for lyophilization and in vivo administration. A 6-methacrylamido-6-deoxy trehalose (MAT) monomer was synthesized from trehalose and polymerized via reversible addition-fragmentation chain transfer (RAFT) polymerization to yield pMAT 43 . The pMAT 43 macro-chain transfer agent was then chain-extended with aminoethylmethacrylamide (AEMA) to yield three different pMAT- b -AEMA cationic-block copolymers, pMAT- b -AEMA-1 (21 AEMA repeats), -2 (44 AEMA repeats), and -3 (57 AEMA repeats). These polymers along with a series of controls were used to form polyplexes with plasmids encoding firefly luciferase behind a strong ubiquitous promoter. The trehalose-coated polyplexes were characterized in detail and found to be resistant to colloidal aggregation in culture media containing salt and serum. The trehalose-polyplexes also retained colloidal stability and promoted high gene expression following lyophilization and reconstitution. Cytotoxicity, cellular uptake, and transfection ability were assessed in vitro using both human glioblastoma (U87) and human liver carcinoma (HepG2) cell lines wherein pMAT- b -AEMA-2 was found to have the optimal combination of high gene expression and low toxicity. pMAT- b -AEMA-2 polyplexes were evaluated in mice via slow tail vein infusion. The vehicle displayed minimal toxicity and discouraged nonspecific internalization in the liver, kidney, spleen, and lungs as determined by quantitative polymerase chain reaction (qPCR) and fluorescence imaging experiments. Hydrodynamic infusion of the polyplexes, however, led to very specific localization of the polyplexes to the mouse liver and promoted excellent gene expression in vivo.