title: Surface properties of quantum dots define their cellular endocytic routes, mitogenic stimulation and suppression of cell migration.
abstract: The practical use of quantum dots (QD) as diagnostic, visualizing and therapeutic nano-agents depends on the understanding of fundamental mechanisms of their entrance and trafficking within cells. Here we show that CdSe/ZnS carboxylic-coated QD (COOH-QD) enter fibroblast cells via lipid raft/caveolin-mediated endocytosis, pass early sorting endosomes and accumulate in the multivesicular bodies, but not in the lysosomes. Later phase of their endocytosis leads to the generation of lipid raft/caveolin-dependent endocytosis inhibition that prevents intracellular uptake of new COOH-QD, but not the QD coupled with platelet-derived growth factor BB (PDGF-QD). PDGF-QD enter fibroblasts by the clathrin-mediated endocytosis and undergo similar intracellular trafficking as COOH-QD, yet they accumulate in lysosomes in contrast to COOH-QD. The PDGF-QD activate PDGF receptor-beta and are mitogenic, however, COOH-QD suppress cell migration and chemotaxis. Data show that surface coating of QD with the biologically active proteins redirects their intracellular traffic routes and changes their biological activity.
authors.forename: Vitalijus
authors.initials: V
authors.lastname: Karabanovas
authors.forename: Zigmantas
authors.initials: Z
authors.lastname: Zitkus
authors.forename: Dalius
authors.initials: D
authors.lastname: Kuciauskas
authors.forename: Ricardas
authors.initials: R
authors.lastname: Rotomskis
authors.forename: Mindaugas
authors.initials: M
authors.lastname: Valius
mesh_terms: D000818:Animals; D022461:Caveolins / Q000378:metabolism*; D002465:Cell Movement / Q000502:physiology*; D004705:Endocytosis / Q000502:physiology*; D021962:Membrane Microdomains / Q000737:chemistry / Q000502:physiology*; D051379:Mice; D008938:Mitosis / Q000502:physiology*; D050258:Mitosis Modulators / Q000378:metabolism*; D041681:NIH 3T3 Cells; D045663:Quantum Dots
chemical_list: D022461:Caveolins; D050258:Mitosis Modulators