Imagine being able to rebuild damaged heart tissue using engineered cells. In this interview, Dr. Adam Feinberg, Professor and Biomedical Engineer at Carnegie Mellon University discusses the biomaterial developments he and his team are currently devising, including “developmentally-inspired” tissue engineering scaffolds.

Could you share with us the biomaterial developments you will look into thanks to funding from the National Institutes of Health Director’s New Innovator Award?

We are developing technologies that mimic the way cells build materials.  Collagen is a main biomaterial of the human body that cells assemble into a highly organized, 3-D scaffold, but it has proven difficult to recapitulate this complicated hierarchical architecture using manmade methods.  The surface-imitated assembly (SIA) technique we have created enables us to build collagen and other extracellular matrix (ECM) protein fibers on a surface, analogous to the way cells build these same protein fibers on their cell membranes. We are applying this technology in cardiac and ophthalmic tissue engineering applications.

Your expertise is in engineering muscle tissue to repair the heart. Could you describe the heart-tissue regeneration process you’re developing that is inspired by the growing human embryo?

The human heart cannot regenerate after a heart attack (myocardial infarction) because the muscle cells (cardiomyocytes) cannot divide in order to generate new cells to repair the damage. However, we can get new human cardiomyocytes from pluripotent stem cells. The problem is that these neo-cardiomyocytes are embryonic in their behavior and are equivalent to cardiomyocytes from early stages of embryonic development. Thus, we are building tissue engineering scaffolds that are inspired by the structure and composition of the human heart during early development in order to provide an environment that will improve the ability of these neo-cardiomyocytes to form functional heart tissue. We call this using “developmentally-inspired” tissue engineering scaffolds. At first we plan to engineer human heart muscle tissue that can be used in vitro for drug discovery and drug toxicity applications. Longer term we hope to engineer heart muscle regeneration approaches that will be used in vivo to repair heart damage.

Would you touch on the repair kit you’re working on that will repair heart injury and disease?

We are not building a repair kit, but are developing nascent repair strategies. For example, our work in 3-D bioprinting combines the advances we have made using SIA to engineer developmentally-inspired tissue scaffolds with the 3-D printing of larger collagen based scaffolds. This is the approach we are using to engineer cardiac tissue large enough to repair large muscle tissue deficits.

Although the heart is your specialty, could your developments and techniques be implemented in other areas of the body?

The developments we are making in cardiac are also being applied to other areas. One area is skeletal muscle tissue engineering, which has many similarities to cardiac muscle. Here we are using human skeletal muscle precursor cells and differentiating them into functional skeletal muscle for in vitro and in vivo applications. A second area in which we are applying these technologies is in ophthalmic tissue engineering. Here we are bioengineering a corneal endothelium, which we hope will be used to repair diseased corneas in human patients as a viable option instead of a cornea transplant.