Will we ever grow replacement hands?

It might seem unbelievable, but researchers can grow organs in the laboratory. There are patients walking around with body parts which have been designed and built by doctors out of a patient's own cells.

There is a pressing need. A shortage of available organs means many die on waiting lists and those that get an organ must spend a lifetime on immunosuppressant drugs to avoid rejection.
The idea is that using a patient's own stem cells to grow new body parts avoids the whole issue of rejection as well as waiting for a donor.
Dr Anthony Atala, director of the Institute for Regenerative Medicine at the Wake Forest Baptist Medical Center in North Carolina, US, has made breakthroughs in building bladders and urethras....
"We've been able to implant the first three in humans. We don't have any examples yet of solid organs in humans because its much more complex," Dr Atala told the BBC......

Building a scaffold for the bladder is one thing, building one for the heart is far more complicated. One of the problems when you move to larger organs is the getting the blood supply to work, connecting arteries, capillaries and veins to keep the organ alive.
It is why some researchers are investigating "decellularisation" - taking an existing donated organ, stripping out the original cells and replacing them with new cells from the patient who will receive the organ.
Prof Martin Birchall, a surgeon at University College London, has been involved in a number of windpipe transplants performed in this way.
The technique starts with a donor windpipe which is then effectively put through a washing machine. Repeated cycles of enzymes and detergents break down and wash away the host cells.
What is left behind is a web of proteins, mostly collagens and elastins, which give the windpipe its structure. It would look and feel like a windpipe, just without cells - a natural scaffold.
The next steps are very similar to those for making the bladder. Stem cells are taken, this time from bone marrow, and grown in a lab before being layered onto the scaffold.
The first patient was fitted with one of these windpipes in Spain in 2008.  Prof Birchall said: "We've made some inroads by starting with the windpipe. We're looking at some other tissues now like the oesophagus and diaphragm and overseas the big breakthroughs have been in building the bladder and urethra.
"Those are the areas in which immediate breakthroughs have occurred, but I see a raft of further first-in-man studies in other organs happening in the next five years."...

Source/Read More: BBC News http://www.bbc.co.uk/news/health-16679010