Garrett Neese/Daily Mining Gazette Parisa Pour Shahid Saeed Abadi, an assistant professor of mechanical engineering at Tech, above, is co-author of a new paper demonstrating the improvements in functionality and rate of growth for heart muscle cells grown in three-dimensional substrates.

HOUGHTON — To grow the sturdiest replacement heart muscle cells, put them in situations that mimic the cells’ natural environment.

That’s the conclusion of researchers from Michigan Technological University, who worked in conjunction with Harvard Medical School on a project to grow the cells, known as cardiomyocytes, in a three-dimensional environment.

The current process involves converting stem cells into cardiomyocytes through biochemical signals, but that method has led to cells that reach maturity more slowly, are underdeveloped, and are more likely to be rejected.

“Most of the current methods are based on biochemical treatment, biochemical methods, but when we use biomechanical and biophysical methods, then it mimics the natural environment for these cells, and, as a result, we are able to get better results,” said Parisa Pour Shahid Saeed Abadi, an assistant professor of mechanical engineering at Tech.

Instead of growing the cells in a petri dish, Abadi and her team make a three-dimensional mold using polydimethylsiloxane (PDMS), a polymer whose molding capabilities make it common in microfluidic research.

Through the substrate, the cells are subjected to the kinds of pressure and physical forces that a normal heart cell would undergo.

“These substrates have the three-dimensional shape of the cells,” said Abadi, who began researching the cells during a post-doctoral fellowship at Brigham and Women’s Hospital at Harvard Medical School. “So they help the maturation of these cells by directing their growth and functionality.”

Without a substrate, a cell will beat in all directions. The substrate guided that to the longitudinal direction of the cells, as occurs in the heart. The beating is also stronger, Abadi said.

The substrate also shows results sooner than traditional methods.

“Some of the effects that we were able to visualize took place just as soon as one day after we had the cell in the substrate,” she said.

The next step for the project is testing them in smaller animals, then larger ones, before clinical trials on humans. Another project will also look at using electrical conductivity to stimulate the cells for better growth.

Ultimately, the cells could replace the injection of stem cells in treatment of defective or damaged heart cells.

“If it’s cardiomyocytes instead, functional cardiomyocytes, then the repair will be more effective and faster,” Abadi said. “So these could be cardiomyocytes derived from stem cells from the same patients. so we are hoping that it will be much more effective in these cases.”