title: Polymer-peptide delivery platforms: effect of oligopeptide orientation on polymer-based DNA delivery.
abstract: The success of nonviral transfection using polymers hinges on efficient nuclear uptake of nucleic acid cargo and overcoming intra- and extracellular barriers. By incorporating PKKKRKV heptapeptide pendent groups as nuclear localization signals (NLS) on a polymer backbone, we demonstrate protein expression levels higher than those obtained from JetPEI and Lipofectamine 2000, the latter being notorious for coupling high transfection efficiency with cytotoxicity. The orientation of the NLS peptide grafts markedly affected transfection performance. Polymers with the sequence attached to the backbone from the valine residue achieved a level of nuclear translocation higher than the levels of those having the NLS groups attached in the opposite orientation. The differences in nuclear localization and DNA complexation strength between the two orientations correlated with a striking difference in protein expression, both in cell culture and in vivo. Polyplexes formed from these comb polymer structures exhibited transfection efficiencies superior to those of Lipofectamine 2000 but with greatly reduced toxicity. Moreover, these novel polymers, when administered by intramuscular ultrasound-mediated delivery, allowed a high level of reporter gene expression in mice, demonstrating their therapeutic promise in vivo.
authors.affiliation: Polymer Science and Engineering Department, University of Massachusetts , 120 Governors Drive, Amherst, Massachusetts 01003, United States.
authors.forename: Sangram S
authors.initials: SS
authors.lastname: Parelkar
authors.forename: Rachel
authors.initials: R
authors.lastname: Letteri
authors.forename: Delphine
authors.initials: D
authors.lastname: Chan-Seng
authors.forename: Olga
authors.initials: O
authors.lastname: Zolochevska
authors.forename: Jayne
authors.initials: J
authors.lastname: Ellis
authors.forename: Marxa
authors.initials: M
authors.lastname: Figueiredo
authors.forename: Todd
authors.initials: T
authors.lastname: Emrick
mesh_terms: D021581:Active Transport, Cell Nucleus; D000818:Animals; D045744:Cell Line, Tumor; D004247:DNA / Q000008:administration & dosage; D003851:Deoxyribonucleases / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D018014:Gene Transfer Techniques; D017930:Genes, Reporter; D006801:Humans; D008055:Lipids / Q000008:administration & dosage; D008297:Male; D008810:Mice, Inbred C57BL; D019913:Nuclear Localization Signals / Q000235:genetics; D010051:Ovarian Neoplasms / Q000235:genetics; D010455:Peptides / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D014162:Transfection
chemical_list: D008055:Lipids; C086724:Lipofectamine; D019913:Nuclear Localization Signals; D010455:Peptides; D011108:Polymers; D004247:DNA; D003851:Deoxyribonucleases