Lesson 4: Why did the man who got a successful face transplant last year die?

Hi,

I was reading about the Chinese farmer Li Guoxing (above) who died last week after a successful face transplant carried out last year.

Q: Why did he die after so many months of successful transplant?
A: He did not continue to take the prescribed anti-tissue rejection drugs.

Q: What is tissue rejection?
A: When we transplant a tissue or organ from one person to another, if they are not identical twins, the cells of the donated tissue will be attacked by the recipient's immune system and die cell by cell. Our immune system consists of the white blood cells and their arsenal of antibodies. The immune system is analogous to the defence system of Singapore. The police, army, navy and air force together with the civil defence do a pretty good job of defending our country from being invaded by enemies and other hostile elements.

In the same way there are several types of white blood cells and their secretions to defend our body against foreign invaders in our body.

Phagocytes move about amongst the tissue cells in a amoeba-like fashion. They travel in the blood stream and squeeze out of the capillaries to reach the tissues. They are able to engulf and "swallow" the foreign invaders. Then digestive enzymes kill and destroy the pathogen and other foreign invaders.

This video shows a phagocyte 'in hot pursuit' of a germ, which it catches eventually (phagocytosis) — "book him Danno!"

B-Lymphocytes, another type of WBC, produces antibodies. These are chemical molecules that attach themselves to pathogens and act as "markers" or "tag" for the phagocytes to come forward to swallow and destroy the pathogens. This process is called phagocytosis.

Another function of antibodies is to cause the pathogens to stick together or "clump" and thus immobilise them. This allows time for the phagocytes to rush to the site of infections to destroy the invaders.


A third function of antibodies is to neutralise the toxins produced by pathogens. These toxins (produced by the pathogens) affect chemical processes in our cells.

There are different types of leucocytes, or white blood cells. We are most familiar with neutrophils as the main constituent of pus

As you can see, the immune response is very good at keeping germs and other invaders of the body from harming us. However, in organ or tissue transplants, the WBCs do not know that these transplanted cells are not invaders. Hence transplant recipients have to take drugs to stop the WBCs from doing the job they are supposed to do. These 'Immuno-suppressant' drugs suppress the immune response of the body. They have to be taken for the rest of the patient's life. If the drugs are stopped, then his WBCs will start killing the cells of the transplanted organ.

This must have happened to the poor farmer in China because he stopped taking his Immuno-suppressant drugs.

A big problem with taking Immuno-suppressant drugs over a long period of time is that it increases one's risk of infection by all manner of microorganisms because one's Immune system would be rendered incapable of fighting infections like it routinely does in a healthy person.

Taking immuno-suppressants over a long period of time also increase a person's cancer risk. Anyone who is considering a face transplant, or any other organ transplants from persons whose tissues are not genetically identical to you would have to decide whether the benefits outweighed the risks.

Red blood cells with bits of fibrin, aka erythrocytes. The fibrin is a clotting agent

Q: Why is it important to receive the "right" type of blood from the blood bank?
A: Blood is a tissue, a liquid tissue. Our immune system will destroy the invaders (donor's blood cells) if they are not genetically closely matched with our cells. At the same time, the WBCs and antibodies in the donor's plasma will attack our body cells.

In blood transfusion, it is important to match the blood type from the donor with that of the recipient. This is of utmost importance. If the "wrong" blood group blood is transfused, the red blood cells will be clumped together to form lumps, and then burst.

The surface of red blood cells contain a type of protein called antigens (called A and B).
Blood is arranged by these antigens into blood types A, B, AB (contains both antigens), and O (contains neither antigen). The liquid part of blood (plasma) has antibodies against the opposite antigen. A person with Type A blood, for example, has antibodies against the B antigen.

So if blood of an unacceptable blood group is transfused, the immune system attacks the donated blood cells, causing them to burst. This may cause serious symptoms, including kidney failure and shock. Antigens also occur in other parts of blood, including white blood cells, a type of blood cell called platelets, and plasma proteins.

Donated blood is put into ABO and Rh groups (another type of blood grouping) to reduce the risk of transfusion reaction.

Before a transfusion, patient and donor blood is often tested (cross-matched) to see if it is compatible. A small amount of donor blood is mixed with a small amount of patient blood. The mixture is checked under a microscope for signs of antibody reaction. It is safe to proceed with the transfusion only if no antibody reaction takes place.

Cheers