U of M researchers create beating heart in laboratory

The biggest problems re going to be cancer, genetic problems that only arise as we age, and perhaps most important of all, neurodegenerative diseases. The problem is that our cells are pre-programmed to only divide a fixed number of times, hence why stem cells help, but even they are limited. When this is "fixed" so the cells can divide indefinitely, it tends to turn into cancer, which is probably one reason this mechanism evolved in the first place.

I don't think they can. The reason they use the "decellularized heart" is because they need a scaffold for the cells to grow on. This has basically been what's holding back growing organs.

They may, however, be able to use another mammal's heart for the scaffold, such as a cow or pig, with the help of some genetic engineering. I read something a while back about a group of scientists that genetically engineered a pig so that its organs could be transplanted into humans. If I remember correctly, a pig's organs have a salty layer on them or something making them incompatible with humans.