Adult Heart Cell Found to have Same Capability as Embryonic Stem Cell

University of Minnesota, January 20, 2007

Capable of developing into all types of cardiac cells, a new cell type in adult rat heart tissue has been found by researchers at the University of Minnesota.

This gives hope for the possibility of treatments such as the growth of new blood vessels for use in bypass surgery or to repair damaged heart muscle after a heart attack. The cells could be expanded in a lab after being harvested and then used in therapy.

Appearing in the February print edition, The journal Nature Clinical Trials Cardiovascular Medicine has published the research.

The researchers expanded tissue taken from adult rat hearts in a dish after adding certain growth factors. These cells were able to give rise to all types of cardiac cells, such as the cells that make up the left and right ventricles and blood vessels. Impressively, just as more mature heart muscle cells will do, the newly grown cells even beat in a laboratory dish.

Professor of physiology and director of the Center for Cardiovascular Repair, Doris, said that they injected the cells into rats with injured hearts and documented that the cells repaired the damaged tissue.

“They appear at this time to be the ideal cell to use for cardiac repair,” Doris said. “They do everything embryonic cardiac cells do, and they don’t create teratomas, or tumors.”

Typically, it takes 2 million to 2 billion cells to make an effective therapeutic dose explained Doris. The cells her lab found can be grown in the laboratory to the number necessary to make an effective treatment in a relatively short period of time and appear more immature than previously described cells. Prior research had only shown more mature cells capable of differentiating into different types of cardiac tissue.

Other types of cells are currently being evaluated in a number of clinical trials, they include muscle tissue cells and bone marrow. Doris says that those tests have not been as effective as once hoped, but they still hold promise for the future. In contrast to cells currently in use for clinical trials, Doris believes the group of cells she and her team have identified will prove to be more potent.

The next step will be to try the experiment in a larger animal model, such as a pig, and then move forward to growing the cells from human heart tissue.