Abstract 18077: Endothelial Behavior and Signaling on Micro and Submicro- Patterned Titanium
Reestablishment of functional endothelium is crucial to long-term success in vascular stenting. However, numerous studies have shown potential for endothelial dysfunction on current drug eluting stents (DES), due to their reliance upon anti-inflammatory and immunosuppressive drugs for suppression of neointimal hyperplasia. We report results demonstrating that EC adhesion, proliferation, and morphology on Ti substrates can be enhanced significantly in vitro through surface patterning with gratings composed of periodic arrays of grooves with widths as small as 0.5 μm. We further asses the EC function on these surfaces. Patterned substrates were fabricated using our Ti deep reactive ion etching (Ti DRIE) process. After substrate sterilization, HECs were seeded and cultured for 1-3 days. Substrates were then rinsed with phosphate buffered solution (PBS) and adherent HECs were fixed and permeabilized and immuno-histo chemistry was performed and imaged using confocal fluorescent techniques, and processed. Figure 1 shows HECs aligned in the direction of sub-micron grooves and the corresponding signaling results. Activation of vWF, a vital anti-thrombotic, was significantly enhanced on all grating sub-patterns relative to unpatterned control (p value=0.05). Activation of eNOS, a potent vasodilator, generally increased with decreasing feature size. The phosphorylation of AMPK, which is reported to enhance cell polarity and division, was significantly higher on submicron-patterns of 0.75 and 0.5 μm (p value=0.5). Expression of VE Selectin, a metastatic cancer marker, was suppressed on most gratings. Finally, VCAM1, an anti-inflammatory, was negatively transcribed on sub-μm gratings (p value=0.05). These results demonstrate that nanopatterning can promote activation and suppression of atheroprotective and atheroscleotic biomolecules in vitro, thus suggesting promise for promoting native functionality in vivo.
- © 2013 by American Heart Association, Inc.