Vascular tissue engineering by computer-aided laser micromachining

Abstract

Many conventional technologies for fabricating tissue engineering scaffolds are not suitable for fabricating scaffolds with patient-specific attributes. For example, many conventional technologies for fabricating tissue engineering scaffolds do not provide control over overall scaffold geometry or over cell position within the scaffold. In this study, the use of computer-aided laser micromachining to create scaffolds for vascular tissue networks was investigated. Computer-aided laser micromachining was used to construct patterned surfaces in agarose or in silicon, which were used for differential adherence and growth of cells into vascular tissue networks. Concentric three-ring structures were fabricated on agarose hydrogel substrates, in which the inner ring contained human aortic endothelial cells, the middle ring contained HA587 human elastin and the outer ring contained human aortic vascular smooth muscle cells. Basement membrane matrix containing vascular endothelial growth factor and heparin was to promote proliferation of human aortic endothelial cells within the vascular tissue networks. Computer-aided laser micromachining provides a unique approach to fabricate small-diameter blood vessels for bypass surgery as well as other artificial tissues with complex geometries.

Fabrication of 3D Biomimetic Microfluidic Networks in Hydrogels

“…Conversely, microfabrication techniques allow for direct control over microfluidic architecture, but in general lack the resolution to recapitulate the highly tortuous and dense vascular networks formed in vivo. Lithographic molding, computer‐aided laser micromachining, and direct‐write assembly have been used to create geometrically simple microfluidic systems consisting of planar, three‐sided channels on the surface of a matrix. Planar microfluidic networks completely embedded in polymer have been fabricated using advanced lithographic molding, injection molding, strategic placement and removal of needles, and printing of sacrificial materials in self‐healing hydrogels .…”

Accurate flow in augmented networks (AFAN): an approach to generating three-dimensional biomimetic microfluidic networks with controlled flow

“…20 While many existing microfabrication approaches allow for direct control over 2D, planar networks, they do not duplicate the complex 3D structure of in vivo networks. 25 A few techniques to generate 3D, non-planar networks have been developed, including 3D printing of sacri-flcial carbohydrate glass, 26 modular assembly, 27 and 3D bio-printing. 28 These approaches have been implemented to increase cell viability in larger volume constructs, 26 to create a perfusable microfluidic hydrogel, 27 and to spatially organize both cells and vasculature in a tissue construct.…”

The next generation of biomaterial development

“…The relationship between texture, wetting and in vitro biocompatibility is examined. Doraiswamy & Narayan (2010) discuss the use of laser micromachining to create scaffolds for vascular tissue networks. Concentric three-ring structures were fabricated for differential adherence and growth of cells.…”