title: Targeting vault nanoparticles to specific cell surface receptors.
abstract: As a naturally occurring nanocapsule abundantly expressed in nearly all-eukaryotic cells, the barrel-shaped vault particle is perhaps an ideal structure to engineer for targeting to specific cell types. Recombinant vault particles self-assemble from 96 copies of the major vault protein (MVP), have dimensions of 72.5 x 41 nm, and have a hollow interior large enough to encapsulate hundreds of proteins. In this study, three different tags were engineered onto the C-terminus of MVP: an 11 amino acid epitope tag, a 33 amino acid IgG-binding peptide, and the 55 amino acid epidermal growth factor (EGF). These modified vaults were produced using a baculovirus expression system. Our studies demonstrate that recombinant vaults assembled from MVPs containing C-terminal peptide extensions display these tags at the top and bottom of the vault on the outside of the particle and can be used to specifically bind the modified vaults to epithelial cancer cells (A431) via the epidermal growth factor receptor (EGFR), either directly (EGF modified vaults) or as mediated by a monoclonal antibody (anti-EGFR) bound to recombinant vaults containing the IgG-binding peptide. The ability to target vaults to specific cells represents an essential advance toward using recombinant vaults as delivery vehicles.
authors.affiliation: Department of Biological Chemistry, David Geffen School of Medicine at UCLA, Los Angeles, California 90095-1737, USA.
authors.forename: Valerie A
authors.initials: VA
authors.lastname: Kickhoefer
authors.forename: Muri
authors.initials: M
authors.lastname: Han
authors.forename: Sujna
authors.initials: S
authors.lastname: Raval-Fernandes
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Poderycki
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Moniz
authors.forename: Dana
authors.initials: D
authors.lastname: Vaccari
authors.forename: Mariena
authors.initials: M
authors.lastname: Silvestry
authors.forename: Phoebe L
authors.initials: PL
authors.lastname: Stewart
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Kelly
authors.forename: Leonard H
authors.initials: LH
authors.lastname: Rome
mesh_terms: D000818:Animals; D001665:Binding Sites; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism*; D003713:Dendritic Cells / Q000378:metabolism; D000939:Epitopes / Q000737:chemistry; D066246:ErbB Receptors / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D007074:Immunoglobulin G / Q000737:chemistry; D051379:Mice; D053758:Nanoparticles / Q000737:chemistry*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011956:Receptors, Cell Surface / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000939:Epitopes; D007074:Immunoglobulin G; D011956:Receptors, Cell Surface; D066246:ErbB Receptors