title: Nanoparticle-mediated cytoplasmic delivery of proteins to target cellular machinery.
abstract: Despite recent advances in nanomaterial-based delivery systems, their applicability as carriers of cargo, especially proteins for targeting cellular components and manipulating cell function, is not well-understood. Herein, we demonstrate the ability of hydrophobic silica nanoparticles to deliver proteins, including enzymes and antibodies, to a diverse set of mammalian cells, including human cancer cells and rat stem cells, while preserving the activity of the biomolecule post-delivery. Specifically, we have explored the delivery and cytosolic activity of hydrophobically functionalized silica nanoparticle-protein conjugates in a human breast cancer cell line (MCF-7) and rat neural stem cells (NSCs) and elucidated the mechanism of cytosolic transport. Importantly, the proteins were delivered to the cytosol without extended entrapment in the endosomes, which facilitated the retention of biological activity of the delivered proteins. As a result, delivery of ribonuclease A (RNase A) and the antibody to phospho-Akt (pAkt) resulted in the initiation of cell death. Delivery of control protein conjugates (e.g., those containing green fluorescent protein or goat antirabbit IgG) resulted in minimal cell death, indicating that the carrier-mediated toxicity was low. The results presented here provide insight into the design of nanomaterials as protein carriers that enable control of cell function.
authors.affiliation: Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
authors.forename: Shyam Sundhar
authors.initials: SS
authors.lastname: Bale
authors.forename: Seok Joon
authors.initials: SJ
authors.lastname: Kwon
authors.forename: Dhiral A
authors.initials: DA
authors.lastname: Shah
authors.forename: Akhilesh
authors.initials: A
authors.lastname: Banerjee
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Dordick
authors.forename: Ravi S
authors.initials: RS
authors.lastname: Kane
mesh_terms: D000818:Animals; D002417:Cattle; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003593:Cytoplasm / Q000378:metabolism*; D004337:Drug Carriers / Q000737:chemistry* / Q000378:metabolism* / Q000633:toxicity; D011992:Endosomes / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D055767:Immobilized Proteins / Q000737:chemistry / Q000378:metabolism; D053758:Nanoparticles; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D051381:Rats; D015398:Signal Transduction; D012822:Silicon Dioxide / Q000737:chemistry / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism
chemical_list: D004337:Drug Carriers; D055767:Immobilized Proteins; D011506:Proteins; D012822:Silicon Dioxide