Question: Could humans use different animal organs to live instead of using Human ones?

John Foster answered on 12 Mar 2014:

In theory, yes. Pigs have similar size hearts with the same ability to pump blood. Parts of pigs hearts have been used to mend human hearts, such as replacing valves that regulate blood flow. Chemicals from animals have also been used. A hormone called insulin is important for regulating blood sugar levels and is either lost or doesn’t work as well in people with diabetes. Before we could make insulin in the lab, pig insulin was given to diabetic patients instead.

However, there is still a big problem with organ rejection, this is where the body of the person receiving the organ fights against the new organ and begins to destroy it. This even happens sometime when you transplant an organ from one human to another. Patient receiving organs have to be matched to make sure their tissue type is a close match to the donor of the organ. Then the patient needs to take drugs to slow their immune system response to the incoming organ.

This would be even more difficult with animal organs as they would be even more different to a human patient. Researchers are now more interested in the possibility of growing organs in the lab from human stem cells, one group recently grew a liver from stem cells.