Basically you take a bit from one person and put it in someone else - don't say we don't tell it like it is!
Transplants are tricky. Donors and recipients need to be carefully matched to minimize rejection of the new tissue. Generally the recipient will have to take immunosuppressant drugs for the rest of their life. These drugs override the body's usual response to foreign tissue, which is to attack it as if it were a disease.
Needless to say there are never enough donors.
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