3D patterned substrates for bioartificial blood vessels – The effect of hydrogels on aligned cells on a biomaterial surface

作者：Xinxin Zhao, Scott A. Irvine, Animesh Agrawal, Ye Cao, Pei Qi Lim, Si Ying Tan, Subbu S. Venkatraman · 发表于：Acta Biomaterialia · 年份：2015 · DOI：10.1016/j.actbio.2015.08.024 · 被引用次数：39 · 研究领域：3D Printing in Biomedical Research、Polymer Surface Interaction Studies、Tissue Engineering and Regenerative Medicine

The optimal bio-artificial blood vessel construct is one that has a compliant tubular core with circumferentially aligned smooth muscle cells (SMCs). Obtaining this well-aligned pattern of SMCs on a scaffold is highly beneficial as this cellular orientation preserves the SMC contractile phenotype. We used 3D patterning to create channels on a polycaprolactone (PCL) scaffold; SMCs were then found to be aligned within the microchannels. To preserve this alignment, and to provide a protective coating that could further incorporate cells, we evaluated the use of two hydrogels, one based on poly(ethylene glycol) diacrylate (PEGDA) and the other based on gelatin. Hydrogels were either physically coated on the PCL surfaces or covalently linked via suitable surface modification of PCL. For covalent immobilization of PEGDA hydrogel, alkene groups were introduced on PCL, while for gelatin covalent linkage, serum proteins were introduced. It is, however, crucial that the hydrogel coating does not disrupt the cellular patterning and distribution. We show in this work that both the process of coating as well as the nature of the coating are critical to preservation of the aligned SMCs. The covalent coating methods involving the crosslinking of hydrogels with the surface of PCL films promoted hydrogel retention time on the film as compared with physical deposition. Furthermore, subsequent hydrogel degradation is affected by the components of the cell culture medium, hinting at a possible r...