Nanotopographic Substrates Encourage Endothelial Order
Endothelial progenitor cells create band structures, well-organized capillaries, on line-grated substrates
THURSDAY, Jan. 3 (HealthDay News) -- In a new study, researchers found that endothelial progenitor cells aligned, elongated, reduced their proliferation and migrated better in response to line-grated nanotopographic substrates, suggesting that this technology could be used to create organized vascular structures in vitro. The research was published online Dec. 11 in Advanced Materials.
Christopher J. Bettinger, of the Massachusetts Institute of Technology in Cambridge, Mass., and colleagues created nanotopographic substrates using etched silicon wafers. They compared the response of endothelial progenitor cells (EPCs) on these versus flat substrates.
EPCs showed a faster migration velocity and improved directed migration on the nanotopographic substrates. On linear nanotopographic substrates, EPCs formed band structures containing hundreds of cells, with a well-defined edge. Protein-level expression of a variety of markers remained the same, regardless of substrate type, including CD31, vascular endothelial cadherin, and von Willebrand factor. With the addition of Matrigel, EPCs formed well-defined, better aligned capillary tubes on nanotopographic substrates, compared to randomly oriented capillaries on flat substrates.
"The observations in this study further suggest the continued application and integration of nanotopographic features in tissue engineering systems. For example, biodegradable polymers amenable to soft-lithography could be used in future studies. Furthermore, other vascular progenitor cells and co-culture systems could also be employed to explore the use of systems with physical surface cues for therapeutic applications. This system could also be directly used to study the mechanisms of vascular genesis by investigating the cellular pathways involved in the observed enhanced capillary tube formation," the authors conclude.