A stem cell transplant is more commonly known as a bone marrow transplant (BMT). The reason we use different terms is that in the past the stem cells were obtained just from the bone marrow. Stem cells can be obtained from three different sources i.e. bone marrow or peripheral blood or cord blood.
BASIC STEPS IN A BMT
- The first step is the collection of the bone marrow or stem cells (the harvest) from the donor.
The bone marrow is stimulated into producing extra stem cells by a growth factor – usually G-CSF. The G-CSF is usually given as an injection just under the skin, once a day for four to six days before the harvest. The stem cells move from the bone marrow into the circulating blood where they are collected. The donor has a special cannula inserted and is attached to a stem cell collecting machine. This is called a Peripheral Blood Stem Cell Harvest (PBSC Harvest).
Umbilical cord blood is also a rich source of stem cells
All stem cells can last for up to approximately 72 hours if they are to be given fresh, else they can be frozen and used at a later date.
- The second step is to completely destroy the existing bone marrow of the recepient and thereby help the patient receive the new stem cells.
- The third step is to infuse the bone marrow or the stem cells through the intravenous route, like a blood transfusion. There may be no signs of a new bone marrow growing for two to three weeks, and occasionally it may be a few months before the new bone marrow produces all the components of the blood adequately.