ANN C. FOLEY, PhD
Assistant Professor of Bioengineering
Department of Bioengineering
The ultimate goal of this study is to bioengineer grafts for cardiac regenerative medicine. We envision that this might involve either injection of highly purified cells of specific types into damaged heart tissue or bio-printing of complex grafts consisting of several different cell types within a scaffold of hydrogel. As a first step, we are establishing protocols to isolate highly purified sinoatrial node cells, under chemically defined conditions without the use of genetic modification or the addition of animal-derived growth factors. Such a population of cells would be useful not only for tissue grafts but could also be used for genetic studies of SAN development and drug screening.
The heart is a complex organ comprised of several types of contractile cells including atrial, ventricular and conduction system cells such as the pacemaker cells of the sinoatrial node. These cardiac sub-lineages each have unique morphologies, physiologies and electrophysiologies. A significant unmet goal for cardiac tissue engineering is the ability to generate large quantities of specific and pure populations of these different cardiac sub-types. We have shown that overexpression of TGFβ-Activated Kinase (TAK1) in mouse embryonic stem (ES) cells faithfully and reproducibly biases cardiac differentiation in EBs toward the SAN fate (Legros, in revision) at the expense of other types of cardiac cells. However these studies has been done in the absence of growth factors and as a consequence cardiac cell yield is have been low. In addition, at the moment they rely on the genetic modification of ES cells.