title: Nuclear inclusion of nontargeted and chromatin-targeted polystyrene beads and plasmid DNA containing nanoparticles.
abstract: The nuclear membrane is one of the major cellular barriers in the delivery of plasmid DNA (pDNA). Cell division has a positive influence on the expression efficiency since, at the end of mitosis, pDNA or pDNA containing complexes near the chromatin are probably included by a random process in the nuclei of the daughter cells. However, very little is known about the nuclear inclusion of nanoparticles during cell division. Using the Xenopus nuclear envelope reassembly (XNER) assay, we found that the nuclear enclosure of nanoparticles was dependent on size (with 100 and 200 nm particles being better included than the 500 nm ones) and charge (with positively charged particles being better included than negatively charged or polyethyleneglycolated (PEGylated) ones) of the beads. Also, coupling chromatin-targeting peptides to the polystyrene beads or pDNA complexes improved their inclusion by 2- to 3-fold. Upon microinjection in living HeLa cells, however, nanoparticles were never observed in the nuclei of cells postdivision but accumulated in a specific perinuclear region, which was identified as the lysosomal compartment. This indicates that nanoparticles can end up in the lysosomes even when they were not delivered through endocytosis. To elucidate if the chromatin binding peptides also have potential in living cells, this additional barrier first has to be tackled, since it prevents free particles from being present near the chromatin at the moment of cell division.
authors.affiliation: Laboratory of General Biochemistry and Physical Pharmacy, Ghent Research Group on Nanomedicines, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, 9000 Ghent, Belgium.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Symens
authors.forename: Rudolf
authors.initials: R
authors.lastname: Walczak
authors.forename: Joseph
authors.initials: J
authors.lastname: Demeester
authors.forename: Iain
authors.initials: I
authors.lastname: Mattaj
authors.forename: Stefaan C
authors.initials: SC
authors.lastname: De Smedt
authors.forename: Katrien
authors.initials: K
authors.lastname: Remaut
mesh_terms: D000818:Animals; D001692:Biological Transport; D002467:Cell Nucleus / Q000378:metabolism* / Q000648:ultrastructure; D002843:Chromatin / Q000737:chemistry / Q000378:metabolism*; D042002:Chromatin Assembly and Disassembly; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D018014:Gene Transfer Techniques; D006367:HeLa Cells; D006801:Humans; D008297:Male; D008422:Materials Testing; D008845:Microinjections; D008863:Microspheres; D053758:Nanoparticles / Q000737:chemistry*; D009685:Nuclear Envelope / Q000378:metabolism / Q000648:ultrastructure; D010063:Ovum / Q000378:metabolism; D010316:Particle Size; D010957:Plasmids / Q000378:metabolism*; D011137:Polystyrenes / Q000737:chemistry*; D013094:Spermatozoa / Q000378:metabolism; D014982:Xenopus laevis
chemical_list: D002843:Chromatin; D011137:Polystyrenes; D004247:DNA