Abstract:
The pursuit of an ideal model system to study the pathophysiology of vascular disease has included the use of tissue engineered blood vessels (TEBV), vascularizing engineered volumetric tissue, silicone-based “organ-on-a-chip” platforms, and tissue decellularization; yet we are still far from generating engineered vascular tissue that recapitulates native physiology. 3D bioprinting has led to additive manufacturing approaches for creating fluidic channels; however, it remains challenging to produce continuous networks with vessels ranging from large (>6 mm) to small (<1 mm) diameter using soft native-like extracellular matrix (ECM) that mimics the mechanical properties, geometric organization, and compositional complexity of the cellular and extracellular microenvironment. An ideal engineering strategy would combine the advantages of additive manufacturing with the controlled fluid flow achieved by organ-on-a-chip platforms, and the ECM structure, composition, and biomechanics of decellularized tissue. In this presentation I will highlight recent work on developing i) a fluorescence-based mechanical strain sensor for mapping 3D surface strain of contractile cells, developing tissue, and engineered blood vessels, ii) 3D bioprinted ECM microfluidics using Freeform Reversible Embedding of Suspended Hydrogels (FRESH), and iii) an in-process imaging platform for error detection and 3D gauging using optical coherence tomography (OCT). Together, this work highlights the exciting potential for FRESH printed ECM-based microfluidic scaffolds and vascular tissue engineering that will set the foundation for future work studying how ECM composition, mechanical properties, and fluid flow contribute to vascular disease. In addition to vascular biology, the collagen-based microfluidics and fluorescence strain sensor are platform technologies amenable to other organ systems, and can be utilized to study cell proliferation, metastasis, ECM remodeling, and biomechanics in a 3D environment.
Bio:
Dr. Shiwarski received a B.S. in Cell Biology and Biochemistry from Bucknell University and a Ph.D. in Biology and Neuroscience from Carnegie Mellon University. During his doctoral research, he investigated how opioid receptor membrane trafficking events influence pain inhibition and opioid addiction using advanced live cell fluorescence imaging and analysis techniques to track exocytic and endocytic events. In 2017 he began a postdoctoral fellowship in Dr. Adam Feinberg’s Lab in the Department of Biomedical Engineering at Carnegie Mellon University where he has: 1) studied how biomechanical forces are essential for cellular and tissue physiology by developing a fluorescence-based nanomechanical biosensor to map real-time changes in cell and tissue strain, 2) was a key contributor on the development of the 3D bioprinting technology FRESH 2.0,  which provided the ability to print unmodified collagen into functional components of the human heart, and 3) designed and published a series of open-source hardware and software platforms for 3D bioprinting, bi-axial mechanical testing, and in-process monitoring for additive manufacturing. Dr. Shiwarski has a broad background in cell biology, quantitative imaging, and tissue engineering with specific expertise in live cell fluorescence imaging, cellular biosensors, computational image analysis, 3D bioprinting, and cellular biomechanics. His future work focuses on engineering FRESH printed ECM-based microfluidic scaffolds as a platform technology for vascular tissue engineering that will set the foundation for studying how vascular smooth muscle cell differentiation, ECM composition, mechanical properties, and fluid flow contribute to hypertensive vascular disease. 

Zoom Link: https://umich.zoom.us/j/96508834308

Organized by:
Dr. Brendon Baker,
Assistant Professor, Biomedical Engineering

Dr. David Nordsletten,
Associate Professor, Department of Biomedical Engineering and Cardiac Surgery