As this latest article shows we are approaching the day that failing organs will be replaced by man made organs. That will solve the problems of both availability and rejection that currently keep organ replacement from helping more than a small percentage of the people it could. And while that day is still in the future researchers are closing in on answers that will in the end produce results. These truly are amazing times.
Miniature Human Livers Created in the Lab
ScienceDaily (Oct. 31, 2010) — Researchers at the Institute for Regenerative Medicine at Wake Forest University Baptist Medical Center have reached an early, but important, milestone in the quest to grow replacement livers in the lab. They are the first to use human liver cells to successfully engineer miniature livers that function -- at least in a laboratory setting -- like human livers. The next step is to see if the livers will continue to function after transplantation in an animal model.
"We are excited about the possibilities this research represents, but must stress that we're at an early stage and many technical hurdles must be overcome before it could benefit patients," said Shay Soker, Ph.D., professor of regenerative medicine and project director. "Not only must we learn how to grow billions of liver cells at one time in order to engineer livers large enough for patients, but we must determine whether these organs are safe to use in patients."
To engineer the organs, the scientists used animal livers that were treated with a mild detergent to remove all cells (a process called decellularization), leaving only the collagen "skeleton" or support structure. They then replaced the original cells with two types of human cells: immature liver cells known as progenitors, and endothelial cells that line blood vessels.
The cells were introduced into the liver skeleton through a large vessel that feeds a system of smaller vessels in the liver. This network of vessels remains intact after the decellularization process. The liver was next placed in a bioreactor, special equipment that provides a constant flow of nutrients and oxygen throughout the organ.
After a week in the bioreactor system, the scientists documented the progressive formation of human liver tissue, as well as liver-associated function. They observed widespread cell growth inside the bioengineered organ.
The ability to engineer a liver with animal cells had been demonstrated previously. However, the possibility of generating a functional human liver was still in question.Read more at www.sciencedaily.com