Bone marrow Transplant Bone marrow is the soft, jelly-like tissue that is found in the hollow centre of all large bones. Bone marrow contains stem cells. Stem cells produce red blood cells that carry oxygen around the body, white blood cells that fight infection, and platelets that help stop bleeding. All of these blood cells are produced by the stem cells and released into the blood stream through the veins and thin tissue surrounding the bone. Without the bone marrow and stem cells, blood cannot be produced and we cannot survive. If you have an illness or condition that affects your bone marrow (such as leukaemia), or requires treatment with chemotherapy or radiotherapy, your bone marrow may be damaged. This means that you may need a bone marrow transplant. During a transplant, healthy bone marrow will be introduced into your blood stream. If the transplant is successful, the new bone marrow will begin making healthy blood cells and you will start to get better. Autologous transplant: Healthy bone marrow may be taken from your body before you have chemotherapy or radiotherapy (this is called 'bone marrow harvest') and put back into your body when your treatment is complete. This is sometimes called an autologous transplant, or 'high-dose treatment and stem cell support'. Sometimes the bone marrow might be cleaned or 'purged' of cancer cells before it is put back. Allogenic transplant: Alternatively, you may have a transplant of bone marrow from a donor; this is called an allogenic transplant. Stem cell transplant: It is increasingly more common for stem cells to be collected for transplant instead of the whole bone marrow. This is called a stem cell transplant. Stem cell transplants (also known as PBSC) are similar to bone marrow transplants but an anaesthetic is not necessary to collect the cells and the blood counts usually recover quicker. Glossary Chemotherapy Chemotherapy is a treatment of an illness or disease with a chemical substance, e.g. in the treatment of cancer. Tissue Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection, producing movement or storing fat.   Platelets Platelets are cells in the blood that control bleeding by plugging the broken blood vessel and helping the blood to clot. Donor A donor is a person (living or dead) who donates blood, an organ or other body parts to another person in need. Blood Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart. Dose Dose is a measured quantity of a medicine to be taken at any one time, such as a specified amount of medication. Anaesthetic Anaesthetic is a drug used to either numb a part of the body (local), or to put a patient to sleep (general) during surgery. Radiotherapy Radiation therapy uses x-rays to treat disease, especially cancer. Veins Veins are blood vessels that carry blood from the rest of the body back to the heart. White blood cells White blood cells are the part of blood that fight infection and disease. Red blood cells Red blood cells transport oxygen around the body and remove carbon dioxide. Oxygen Oxygen is an odourless, colourless gas that makes up about 20% of the air we breathe. Stem cells Stem cells are cells that are at an early stage of development, so they still have the ability to turn into any type of cell in the body.