Sung Yun (Hann)1, Haitao (Cui)1, Timothy (Esworthy)1, Kartik (Bulusu)1， Michael W. (Plesniak)1,3, Lijie Grace (Zhang)1,2,3,4&nbsp;1Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, DC 20052, USA2Department of Electrical and Computer Engineering, The George Washington University, Washington, DC 20052, USA3Department of Biomedical Engineering, The George Washington University, Washington, DC 20052, USA4Department of Medicine, The George Washington University Medical Center, Washington, DC 20052, USA&nbsp;E-Mail: shann008@email.gwu.edu (Sung Yun Hann)htcui@email.gwu.edu (Haitao Cui)tesworthy@email.gwu.edu (Timothy Esworthy)bulusu@gwu.edu (Kartik Bulusu)plesniak@gwu.edu (Michael W. Plesniak)lgzhang@email.gwu.edu (Lijie Grace Zhang)&nbsp;To date, there are numerous efforts to engineer small-diameter (&lt;6 mm) blood vessel grafts for therapeutics due to the lack of available vascular autografts or artificial grafts. Among several fabrication techniques, 3D bioprinting has been widely incorporated for tissue and organ regeneration as it holds many strengths, such as superior reproducibility and repeatability of biomimetic artificial tissues. For 3D bioprinted vessel constructs, polylactic acid (PLA) has been widely used as a filament material for fused deposition modeling (FDM) 3D printing due to its decent biocompatibility. However, the fabricated scaffolds often lack flexibility and porosity, which are the critical requirements for blood flow control and nutrition exchange for the neighbor tissues. It is ideal to create elastic and biocompatible vessel grafts that can withstand blood pressures and control unexpected coagulation while maintaining the vessel wall permeability barrier. The objective of this study is to 3D bioprint novel biomimetic small-diameter blood vessels via a rubber-like elastomer that consists of a biocompatible hydrogel inner layer with human-induced pluripotent stem cells (iPSCs). Our results show that the blood vessels can be successfully bioprinted with significantly improved tensile modulus and elongation percentage at the break, with values close to the native human blood vessel, when compared to a PLA control group. In order to create biomimetic endothelium and smooth muscle layers, iPSC-derived endothelial cells (iECs) and iPSC-derived smooth muscle cells (iSMCs)-laden fibrin gel layers were homogenously formed inside the printed tubular structure. The acquired qualification data and cell staining results presented excellent viability and proliferation of the stem cells. In summary, this study provides an innovative bioprinting approach to create biologically inspired small-diameter blood vessel grafts with optimal physical and biological properties for clinical transplantation in the future.&nbsp;Acknowledgments: The authors would like to thank NSF BMMB program grant # 1854415 , and American Heart Association Transformative Project Award for financial support.&nbsp;Keywords: 3D bioprinting, blood vessel, vasculature, stem cell, tissue regeneration

3d Bioprinting Biologically Inspired Ips Cell-Laden Flexible Blood Vessels

Paper Proceedings: https://asmedigitalcollection.asme.org/IMECE/IMECE2021/volume/85543

ASME 2021 International Mechanical Engineering Congress and Exposition (IMECE2021)

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