Stem Cells Could Lead to Biological Pacemaker

(Ivanhoe Newswire) — Animal studies show genetically engineered heart cells from human embryonic stem cells could lead to a biological form of pacemaker, according to a new study.

Researchers at Johns Hopkins School of Medicine in Baltimore injected clusters of human beating heart cells (derived from human embryonic stem cells) into the heart muscle of six guinea pigs. The researchers genetically engineered the stem cells, which were then encouraged to become heart cells.

Results show after the guinea pigs’ own pace-making cells were destroyed (through freezing), electrical measurements revealed a new heartbeat (slower) created by the addition of the human cells. The new electrical signal was traced to the human cells, made easier to locate by their fluorescent glow.

Electronic pacemakers, while lifesaving devices, cannot react to situations like the heart’s own can, such as raising the heart rate when a person is scared or about to climb up a hill.

A pacemaker created by stem cells may bypass this problem. According to lead study author Ronald Li, Ph.D., assistant professor of medicine at Johns Hopkins School of Medicine: “These implanted cells also responded appropriately to drugs used to slow or speed the heart rate, which pacemakers can’t do. But many challenges remain before this technique could be used for patients. If this process isn’t done properly, it could jeopardize a very promising field.”

SOURCE: To be published in an upcoming issue of Circulation