In a post here yesterday, --Creating artificial organs: New 3D printing technique could speed progress-- I mentioned research under way in Scotland to use 3D printing technology to generate human organs for possible transplant or other kinds of research. In essence, they spray cloned human stem cells into organs that can--someday-- be transplanted into people whose organs are failing.
That's one way being researched.
Here's another: At the Texas Heart Institute in Houston, Dr. Doris Taylor and her team "decellularize" the hearts from pigs and other mammals to "clean away" the pig cells, leaving only the scaffold of the heart upon which human stem cells can be placed to regrow into a new heart that can--someday--be implanted into the person who donated those cells.
The advantage of that approach over transplanting a complete heart from a deceased donor: First, there aren't enough hearts to go around; Second, by using this approach, utilizing the patient's own cells, the implantee will not reject the new heart.
Here's the link to that article in the Houston Chronicle, which also carries photos of one of the decellularized pig hearts. The article sums it up thusly: the work there may "reverse disease? [Even] reverse the aging process."
The approach will also -- if the research continues as successfully as it has -- be used with kidneys, livers, and other interntal organs. (To use the technical term: Dr. Taylor's and her team do "whole-organ decellurization."
And how do they clear off the animal cells--that is, decellularize a pig's heart? Simple: by soaking it a couple of days in baby shampoo.
The article about Dr. Taylor and her work concludes with a quote from Gandhi: "First they ignore you, then they laugh at you, then they fight you, then you win."