Beating heart muscle engineered
Scientists have grown a thin strip of heart muscle, which is able to beat spontaneously, using stem cells from a mouse embryo. Currently there are many treatments to prevent a heart attack. However, after a heart attack there is no way to restore the damaged heart muscle.
So far stem cells found in bone marrow have been used in an attempt to kick start stem cells within the heart to grow new cardiac muscle, but this approach has as yet proved unsuccessful. The new study took a more direct approach. The researchers discovered that master heart stem cells were present in both human and mouse embryos. They then engineered mice so that certain cells within the developing heart would glow fluorescent red or green.
When tracking the fluorescence in the developing embryos, the researchers noted the areas where the two colours overlapped. These areas were where the cells responsible for developing heart ventricle muscle were located. The team seeded special scaffolding with these ventricle stem cells and managed to grow a thin strip of mouse heart muscle. Amazingly this muscle strip also spontaneously beat, just like a normal heart tissue strip.
The team are trying to grow thicker, usable portions of muscle. They will also attempt to pinpoint the stem cells that develop blood supply to the heart, so that the new tissue will grow an essntial blood supply.