Question: Why does the body reject a heart transplant?

Fiona Hatch answered on 9 Mar 2012:

Your body is made up of many cells, and each of your cells has a little label on the outside which says it is part of you.

When you catch a cold that is when a bacteria or virus enters your body, your body is able to tell it is not you because it does not have the labels on the outside and so it will kill the bacteria or virus.

Basically anything that does not have your name written on it, your body will destroy.

So when you have a heart transplant, this is a heart from someone else, so it is made up of their cells, NOT yours. Your body does not like having stranger cells inside it and so it will attack those cells. The body rejects the heart because it is not yours and so it does not want it.

During heart transplant operations the doctors give you something called an immunosuppressant, this stops your body attacking stranger cells and allows the body to get use to having those cells. Most of the time this is successful, but sometimes the body will never accept it no matter how many drugs you take.