title: Three-dimensional bioassembly tool for generating viable tissue-engineered constructs.
abstract: The primary emphasis of tissue engineering is the design and fabrication of constructs for the replacement of nonfunctional tissue. Because tissue represents a highly organized interplay of cells and extracellular matrix, the fabrication of replacement tissue should mimic this spatial organization. This report details studies evaluating the use of a three-dimensional, direct-write cell deposition system to construct spatially organized viable structures. A direct-write bioassembly system was designed and fabricated to permit layer-by-layer placement of cells and extracellular matrix on a variety of material substrates. Human fibroblasts suspended in polyoxyethylene/polyoxypropylene were coextruded through a positive displacement pen delivery onto a polystyrene slide. After deposition, approximately 60% of the fibroblasts remained viable. Bovine aortic endothelial cells (BAECs) suspended in soluble collagen type I were coextruded via microdispense pen delivery onto the hydrophilic side of flat sheets of polyethylene terephthalate. After deposition with a 25-gauge tip, approximately 86% of the BAECs were viable. When maintained in culture for up to 35 days, the constructs remained viable and maintained their original spatial organization. These results indicate the potential for utilizing a direct-write, three-dimensional bioassembly tool to create viable, patterned tissue-engineered constructs.
authors.affiliation: Division of Biomedical Engineering, University of Arizona, Tucson, Arizona 85724-5084, USA.
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Smith
authors.forename: Alice L
authors.initials: AL
authors.lastname: Stone
authors.forename: Robert L
authors.initials: RL
authors.lastname: Parkhill
authors.forename: Robert L
authors.initials: RL
authors.lastname: Stewart
authors.forename: Mark W
authors.initials: MW
authors.lastname: Simpkins
authors.forename: Anatoly M
authors.initials: AM
authors.lastname: Kachurin
authors.forename: William L
authors.initials: WL
authors.lastname: Warren
authors.forename: Stuart K
authors.initials: SK
authors.lastname: Williams
mesh_terms: D000818:Animals; D002417:Cattle; D018929:Cell Culture Techniques / Q000379:methods*; D002478:Cells, Cultured; D024042:Collagen Type I / Q000737:chemistry; D016287:Computer Peripherals; D042783:Endothelial Cells / Q000166:cytology* / Q000502:physiology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005347:Fibroblasts / Q000166:cytology* / Q000502:physiology*; D006801:Humans; D008846:Micromanipulation / Q000295:instrumentation* / Q000379:methods; D011327:Printing; D012371:Robotics / Q000295:instrumentation; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D024042:Collagen Type I