Biologically-Engineered Heart Valves that Grow
ABSTRACT
We have developed a biologically-engineered tube of cell-produced collagenous matrix, which is allogeneic upon a decellularization performed prior to implantation and thus “off-the-shelf.” It is grown from dermal fibroblasts entrapped in a sacrificial fibrin hydrogel tube that is then decellularized using sequential detergent treatments. The resulting cell-produced matrix tube possesses physiological strength, compliance, and alignment (circumferential). Using the concept of a tubular heart valve, where the tube collapses inward with back-pressure between 3 equi-spaced constraints placed around the periphery to create one-way valve action, we have created a set of novel heart valves for adults and children that offer indefinite durability and growth potential because the matrix becomes a living tissue with the recipient’s cells post-implantation as shown in multiple growing lamb studies. A robust FEM-based algorithm based on an anisotropic hyperelastic constitutive model was implemented for in silico construction of the novel tri-tube heart valve was developed to facilitate optimization of the leaflet geometry with respect to coaptation area, solid stress, and pinwheel index resulting from simulated closure from applied back-pressure. Preliminary FSI results are also presented.
ABOUT THE SPEAKER Professor Tranquillo received his Ph.D. in Chemical Engineering in 1986 from the University of Pennsylvania. He was a NATO Postdoctoral Fellow at the Center for Mathematical Biology at Oxford for one year before beginning his appointment in the Department of Chemical Engineering & Materials Science at the University of Minnesota in 1987. He served as the head of the Department of Biomedical Engineering from its inception in 2000 until 2019. Professor Tranquillo has used a combined modeling and experimental approach to understand cell behavior, in particular, directed cell migration, and cell-matrix mechanical interactions. More recently, his research program has focused on the role of these cell behaviors in cardiovascular and neural tissue engineering applications. His research program has resulted in over 120 peer-reviewed original research publications as first or senior author, being recognized with his selection for the TERMIS-AM Senior Scientist Award in 2015.Resulting intellectual property for a regenerative cardiovascular material platform technology was licensed by Vascudyne, Inc in 2017. Professor Tranquillo is a Fellow of the American Institute of Medical and Biological Engineering, International Academy of Medical and Biological Engineering, and the Biomedical Engineering Society, and he is also a Distinguished McKnight University Professor.
Event Contact: Angela Dixon