Metabolically stabilized long-circulating PEGylated polyacridine peptide polyplexes mediate hydrodynamically stimulated gene expression in liver.
A novel class of PEGylated polyacridine peptides was developed that mediate potent stimulated gene transfer in the liver of mice. Polyacridine peptides, (Acr-X)(n)-Cys-polyethylene glycol (PEG), possessing 2-6 repeats of Lys-acridine (Acr) spaced by either Lys, Arg, Leu or Glu, were Cys derivatized with PEG (PEG(5000 kDa)) and evaluated as in vivo gene transfer agents. An optimal peptide of (Acr-Lys)(6)-Cys-PEG was able to bind to plasmid DNA (pGL3) with high affinity by polyintercalation, stabilize DNA from metabolism by DNAse and extend the pharmacokinetic half-life of DNA in the circulation for up to 2 h. A tail vein dose of PEGylated polyacridine peptide pGL3 polyplexes (1 μg in 50 μl), followed by a stimulatory hydrodynamic dose of normal saline at times ranging from 5 to 60 min post-DNA administration, led to a high level of luciferase expression in the liver, equivalent to levels mediated by direct hydrodynamic dosing of 1 μg of pGL3. The results establish the unique properties of PEGylated polyacridine peptides as a new and promising class of gene delivery peptides that facilitate reversible binding to plasmid DNA, protecting it from DNase in vivo resulting in an extended circulatory half-life, and release of transfection-competent DNA into the liver to mediate a high-level of gene expression upon hydrodynamic boost.
Fernandez
C A
CA
Divisions of Pharmaceutics and Medicinal and Natural Products Chemistry, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA.
Baumhover
N J
NJ
Duskey
J T
JT
Khargharia
S
S
Kizzire
K
K
Ericson
M D
MD
Rice
K G
KG
D000166:Acridines / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D004247:DNA / Q000008:administration & dosage* / Q000737:chemistry / Q000378:metabolism; D015870:Gene Expression; D018014:Gene Transfer Techniques; D006207:Half-Life; D057446:Hydrodynamics; D008099:Liver / Q000378:metabolism*; D051379:Mice; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D011092:Polyethylene Glycols / Q000737:chemistry / Q000378:metabolism*; D014162:Transfection
D000166:Acridines; D010455:Peptides; D011092:Polyethylene Glycols; D004247:DNA