Bone marrow is a spongy material that is found inside our bones. It is important as it produces special cells known as stem cells.
Stem cells are very useful because they have the ability to create other specialised cells that carry out important functions. The stem cells in bone marrow produce three important types of blood cells:
- Red blood cells, which carry oxygen around the body.
- White blood cells, which help fight infection.
- Platelets, which help stop bleeding.
Bone marrow transplantation
Bone marrow transplantation (BMT) involves taking a healthy sample of stem cells from bone marrow belonging to a healthy donor. This is then injected into your own bone marrow. The new stem cells take over the production of the blood cells.
In some circumstances, it may be possible to take your own bone marrow from another part of your body. The bone marrow is cleared of any diseased cells before being returned. This is known as an autologous transplantation.
BMTs are often required to treat conditions that affect the blood and bone marrow, such as leukaemia (cancer of the white blood cells) or sickle cell anaemia (an inherited condition which causes damage to red blood cells).
Other types of stem cell transplantation
In the past, doctors were only able to get stem cells from bone marrow. However, due to advances in medical technology, it is possible to get them from other sources.
Peripheral blood stem cell (PBSC) donation
A special medicine can be injected into the donor's blood, which causes the stem cells to filter out of their bone marrow and into their bloodstream. An amount of their blood can then be taken out of their body and given to you, in a similar way to a typical blood donation.
This procedure is known as a peripheral blood stem cell (PBSC) donation. The advantage of a PBSC is that the donor does not need to take a general anaesthetic.
Stem cells transplant
Stem cells can also be collected from the umbilical cord of a new born baby. The cells can be stored for many years in a laboratory, known as a cord bank centre, until they are needed. This is known as a cord blood donation. Currently, the number of cord blood cells available for donation is small, but it is hoped they will increase as more parents agree to their child's umbilical cord being used in this way.
Undergoing a stem cell transplant can be an intensive and challenging experience. The medicines used to prepare the body can cause unpleasant side-effects, and there is a risk of complications, such as your body rejecting the new stem cells, the new stem cells attacking your body (known as graft versus host disease, or GVHD) and infection. Many people will take up to one year to fully recover from the procedure.
