@article{zhang_bambharoliya_xie_liu_celik_wang_akkus_king_2021, title={A hybrid vascular graft harnessing the superior mechanical properties of synthetic fibers and the biological performance of collagen filaments}, volume={118}, ISSN={["1873-0191"]}, url={http://dx.doi.org/10.1016/j.msec.2020.111418}, DOI={10.1016/j.msec.2020.111418}, abstractNote={Tissue-engineered small caliber vascular grafts have attracted much research attention as a viable alternative to traditional vascular grafts with their biocompatibility and potential to achieve complete healing. However, the major challenge is to fabricate a scaffold with both satisfactory mechanical properties and fast endothelialization. In this study, a hybrid tubular vascular tissue engineered scaffold has been circular-knitted using novel electrochemically aligned collagen (ELAC) filaments plied together with traditional poly(lactic acid) (PLA) yarn. The collagen component was able to promote the recruitment and proliferation of endothelial cells by increasing the initial cell adhesion 10-fold and the eventual cell population 3.2 times higher than the PLA scaffold alone. At the same time, the PLA yarn was able to provide sufficient mechanical strength and structural stability, as well as facilitate scaffold fabrication on high speed textile production equipment. The tubular hybrid scaffold exhibited excellent bursting strength (1.89 ± 0.43 MPa) and suture retention strength (10.86 ± 0.49 N), and had comparable compliance (3.98 ± 1.94%/100 mmHg) to that of the coronary artery (3.8 ± 0.3%/100 mmHg) under normotensive pressure. With its excellent mechanical and biological performance, this prototype hybrid scaffold is a promising candidate for the construction of a clinically successful and easily translatable tissue-engineered small caliber vascular graft.}, journal={MATERIALS SCIENCE & ENGINEERING C-MATERIALS FOR BIOLOGICAL APPLICATIONS}, publisher={Elsevier BV}, author={Zhang, Fan and Bambharoliya, Tushar and Xie, Yu and Liu, Laijun and Celik, Hakan and Wang, Lu and Akkus, Ozan and King, Martin W.}, year={2021}, month={Jan} }
 @article{xie_chen_celik_akkus_king_2021, title={Evaluation of an electrochemically aligned collagen yarn for textile scaffold fabrication}, volume={16}, ISSN={["1748-605X"]}, DOI={10.1088/1748-605X/abdf9e}, abstractNote={Abstract}, number={2}, journal={BIOMEDICAL MATERIALS}, author={Xie, Yu and Chen, Jiyang and Celik, Hakan and Akkus, Ozan and King, Martin W.}, year={2021}, month={Mar} }
 @article{zhang_xie_celik_akkus_bernacki_king_2019, title={Engineering small-caliber vascular grafts from collagen filaments and nanofibers with comparable mechanical properties to native vessels}, volume={11}, ISSN={["1758-5090"]}, url={https://doi.org/10.1088/1758-5090/ab15ce}, DOI={10.1088/1758-5090/ab15ce}, abstractNote={At the present time, there is no successful synthetic, off-the-shelf small-caliber vascular graft (<6 mm) for the repair or bypass of the coronary or carotid arteries. This stimulates on-going investigations to fabricate an artificial vascular graft that has both sufficient mechanical properties as well as superior biological performance. Collagen has long been considered as a viable material to encourage cell recruitment, tissue regeneration, and revascularization, but its use has been limited by its inferior mechanical properties. In this study, novel electrochemically aligned collagen filaments were used to engineer a bilayer small-caliber vascular graft, by circular knitting the collagen filaments and electrospinning collagen nanofibers. The collagen prototype grafts showed significantly greater bursting strength under dry and hydrated conditions to that of autografts such as the human internal mammary artery and the saphenous vein (SV). The suture retention strength was sufficient under dry condition, but that under hydrated condition needs to be further improved. The radial dynamic compliance of the collagen grafts was similar to that of the human SV. During in vitro cell culture assays with human umbilical vein endothelial cells, the prototype collagen grafts also encouraged cell adhesion and promoted cell proliferation compared to the synthetic poly(lactic acid) grafts. In conclusion, this study demonstrated the feasibility of the use of novel collagen filaments for fabricating small caliber tissue-engineered vascular grafts that provide both sufficient mechanical properties and superior biological performance.}, number={3}, journal={BIOFABRICATION}, publisher={IOP Publishing}, author={Zhang, Fan and Xie, Yu and Celik, Hakan and Akkus, Ozan and Bernacki, Susan H. and King, Martin W.}, year={2019}, month={Jul} }
 @article{xie_guan_kim_king_2016, title={The mechanical performance of weft-knitted/electrospun bilayer small diameter vascular prostheses}, volume={61}, ISSN={["1878-0180"]}, DOI={10.1016/j.jmbbm.2016.04.011}, abstractNote={Cardiovascular disease (CVD) accounts for a significant mortality rate worldwide. Autologous vessels, such as the saphenous vein and the internal mammary artery, are currently the gold standard materials for by-pass surgery. However, they may not always be available due to aging, previous harvesting or the pre-existing arterial disease. Synthetic commercial ePTFE and polyester (PET) are not suitable for small diameter vascular grafts (<6 mm), mainly due to their poor circumferential compliance, rapid thrombus formation and low endothelialization. In order to reduce thrombogenicity and improve cell proliferation, we developed a collagen/elastin knitted/electrospun bilayer graft made of biodegradable and biocompatible poly(lactic acid) (PLA) and poly(lactide-co-caprolactone) (PLCL) polymers to mimic the multilayer structure of native arteries. We also designed the prostheses to provide some of the required mechanical properties. While the bilayer structure had excellent circumferential tensile strength, bursting strength and suture retention resistance, the radial compliance did not show any observable improvement.}, journal={JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS}, author={Xie, Yu and Guan, Ying and Kim, Soo-Hyun and King, Martin W.}, year={2016}, month={Aug}, pages={410–418} }