• Braune, Steffen

Abstract

Background: The patency of small-diameter vascular prostheses is limited by several factors such as thrombogenicity, which is strongly influenced by surface roughness and chemical composition, or a mechanical mismatch between the elastic modulus of an artery and of the vascular prosthesis. A confluent layer of endothelial cells onto the inner surface of vascular prostheses could improve the hemocompatibility of the device. Biomaterials with adjustable elastic properties could be tailored to the values of human arteries so that a prothesis mismatch could be avoided. It was recently demonstrated that a co-culture of endothelial cells with angiogenically stimulated monocytes (aMO2) shows an accelerated formation of a functional confluent endothelial cell monolayer on soft hydrophobic poly(n-butyl acrylate) (cPnBA) networks. In addition, the cell compatibility with vascular smooth muscle cells and aortic fibroblasts, which are other important cell types of the vessel wall, is essential for a vascular prosthesis material and must therefore be explored. Purpose: Here we investigated the interaction of human vascular smooth muscle cells and aortic fibroblasts with cPnBA04 and cPnBA73. Material and methods: Human primary vascular smooth muscle cells and aortic fibroblasts were seeded on the two cPnBAs with different elastic moduli (cPnBA04 - 250 kPa and cPnBA73 - 1100 kPa) over 72 h. A live-dead staining (fluorescein diacetate/propium iodide) was performed to determine the morphology and viability of adherent cells. Furthermore, the extracellular matrix components, the actin cytoskeleton, the cell-material-contacts and the cytokine profiles were analysed. Results: Both cell types adhered and were viable on cPnBA04 and cPnBA73. The level of pro-inflammatory cytokine secretion (IFN-γ and TNF-α) by smooth muscle cells and vascular fibroblasts was comparable to that of cells cultivated on a control material. The release of these cytokines by human fibroblasts was higher on cPnBA73 compared to cPnBA04. Both cell types secreted an extracellular matrix comparable to cells seeded on a control material. Conclusion: The study revealed, that cPnBA with varying elastic moduli are not only suitable for the cultivation of endothelial cells, but also for human vascular smooth muscle cells and aortic fibroblasts. Therefore, cPnBA could be a potential candidate material for the development of cardiovascular prostheses.

Topics

• impedance spectroscopy
• morphology
• surface
• chemical composition
• biomaterials