title: In Vitro Cytotoxicity, Adhesion, and Proliferation of Human Vascular Cells Exposed to Zinc.
abstract: Zinc (Zn) and its alloys have recently been introduced as a new class of biodegradable metals with potential application in biodegradable vascular stents. Although an in vivo feasibility study pointed to outstanding biocompatibility of Zn-based implants in vascular environments, a thorough understanding of how Zn and Zn2+affect surrounding cells is lacking. In this comparative study, three vascular cell types-human endothelial cells (HAEC), human aortic smooth muscle cells (AoSMC), and human dermal fibroblasts (hDF)-were studied to advance the understanding of Zn/Zn2+-cell interactions. Aqueous cytotoxicity using a Zn2+insult assay resulted in LD50values of 50 µM for hDF, 70 µM for AoSMC, and 265 µM for HAEC. Direct cell contact with the metallic Zn surface resulted initially in cell attachment, but was quickly followed by cell death. After modification of the Zn surface using a layer of gelatin-intended to mimic a protein layer seen in vivo-the cells were able to attach and proliferate on the Zn surface. Further experiments demonstrated a Zn dose-dependent effect on cell spreading and migration, suggesting that both adhesion and cell mobility may be hindered by free Zn2+.
authors.affiliation: Department of Biomedical Engineering, Michigan Technological University, Houghton, Michigan, United States.
authors.forename: Emily R
authors.initials: ER
authors.lastname: Shearier
authors.affiliation: Department of Materials Science and Engineering, Michigan Technological University, Houghton, Michigan, United States.
authors.forename: Patrick K
authors.initials: PK
authors.lastname: Bowen
authors.affiliation: Department of Biomedical Engineering, Michigan Technological University, Houghton, Michigan, United States.
authors.forename: Weilue
authors.initials: W
authors.lastname: He
authors.affiliation: Department of Materials Science and Engineering, Michigan Technological University, Houghton, Michigan, United States.
authors.forename: Adam
authors.initials: A
authors.lastname: Drelich
authors.affiliation: Department of Materials Science and Engineering, Michigan Technological University, Houghton, Michigan, United States.
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Drelich
authors.affiliation: Department of Biomedical Engineering, Michigan Technological University, Houghton, Michigan, United States.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Goldman
authors.affiliation: Department of Biomedical Engineering, Michigan Technological University, Houghton, Michigan, United States.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
keywords: biocompatibility; cytotoxicity; in vitro testing; stents; zinc