Stem cells are very early blood cells. They are normally found in the bone marrow. Doctors use growth factor injections to make some of them move into the bloodstream. This makes it easier to collect them. You have growth factors as an injection just under the skin, usually in your tummy (abdomen), or into an arm or a leg. You have these once a day, for up to 10 days at a time and can learn to give them yourself at home.

Growth factor injections can cause itching around the injection site. You may have some aching in your bones after you have had a few injections. This is because there are a lot of blood cells being made inside the bones. The aching is usually easy to control with a mild painkiller, such as paracetamol. The pain will go away after a day or so.

After your course of injections, you will have regular blood tests to see how many stem cells are in your blood. When there are enough, you will have them collected. Collecting stem cells takes 3 or 4 hours. You sit in a chair or lie down on a couch and have a fine tube put into a vein in each of your arms. The nurse attaches these to a machine called a stem cell separator. Your blood passes out of one drip, through the machine and back into your body through the other drip. The machine filters the stem cells out of your blood but gives you the rest of the cells and the plasma back. The donor stem cells are frozen and stored. Most donors need to have another collection the following day, to make sure there are enough cells.

Read more:
Bone marrow and stem cell transplants for chronic myeloid ...