Cheng-Wei “Aaron” Chen
UCI doctoral student Cheng-Wei “Aaron” Chen proposes using human embryonic stem cells to create sheets of cardiomyocytes for repairing damaged heart tissue. Michelle S. Kim / University Communications

Since stem cells were first discovered to be a basis of new medical treatments, researchers have touted their potential to repair the human heart.

Millions of Americans suffer heart attacks each year, and those who survive never fully recover. Left behind is scarred and dead tissue that never mends, and research has focused on utilizing stem cells to initiate new growth.

Recent results show promise. One study this February found that cardiac stem cells regenerated heart muscle in patients who had suffered heart attacks.

UC Irvine doctoral candidate Cheng-Wei “Aaron” Chen is pursuing another approach. He believes that human embryonic stem cells can be used to create tissue — a sort of cardiac patch that could be grafted onto damaged heart areas and stimulate regrowth.

His research has earned him a 2011-12 Public Impact Fellowship. Instituted by Graduate Division Dean Frances Leslie, the $10,000 prize supports UCI grad students whose work has the potential to significantly benefit society.

“Stem cell research is an exciting, emerging field,” Chen says. “There is lots of potential to meet medical needs. That’s why I chose this area.”

He’s also demonstrating that stem cell research is not solely the domain of biology and medicine. After establishing a career in biotechnology, Chen is pursuing a Ph.D. in biochemical engineering to explore novel ways of repairing damaged hearts.

The most common technique for making tissue involves collecting and growing cells in a scaffold, which provides structure and support. However, when it comes to creating cardiac tissue, Chen says, this approach has significant drawbacks.

Scaffolds are too inflexible to properly attach to other cells in the constantly beating heart, and when they dissolve, scaffolds may emit toxins that could prompt a potentially harmful immune response.

Chen proposes a different fabrication method that, he says, overcomes these limitations: linking cells into a sheet. He has developed a substrate with wrinkles on which cells can align, grow and share signals.

To generate these cells, Chen is taking human embryonic stem cells — early-stage cells that can transform into any human cell type — and coaxing them into cardiomyocytes, the building blocks of heart tissue.

His research is still in its infancy, but the goal is to eventually stack the cell sheets and devise functional cardiac patches for use in clinical trials on heart disease patients.

The effort, Chen says, will extend beyond his doctoral studies – he expects to receive his Ph.D. in 2013 – and he plans to take his project into the biotech industry.

“Aaron’s work is important because it brings us one critical step closer to creating therapeutically relevant cardiac cells for heart attack repair,” says Michelle Khine, an associate
professor of biomedical engineering who is supervising Chen’s doctoral program.

“As heart disease is the No. 1 cause of death in the U.S., this would have enormous public impact.”