A bone marrow stem cell transplant is a type of transplant in which stem cells which are capable of differentiating into different kinds of blood cells are transplanted from a donor to a recipient. This type of transplant is seen in the treatment of leukemia and lymphoma, among many other conditions which involve the blood. There are a number of sources for donor material, and thanks to improvements in technology, the cells can sometimes be harvested from the blood, rather than the bone marrow, which reduces risks for donors.
This type of transplant is also known as a hematopoietic stem cell transplant, referencing the type of stem cells involved. Unlike embryonic stem cells, which can differentiate into any kind of cell, hematopoietic cells are only capable of differentiating into blood cells. When they are infused into a patient, they make their way into the bone marrow and start reproducing, generating fresh blood for the patient.
Prior to a bone marrow stem cell transplant, a patient undergoes chemotherapy and radiation which are designed to kill off as many bone marrow stem cells as possible. This makes the patient extremely vulnerable to medical complications, necessitating a hospital stay until the transplant takes place and takes. The patient is usually held in seclusion, with access being tightly controlled because a stray infection could be deadly. This can be frustrating for patients.
One source for donor cells for a bone marrow stem cell transplant may be the patient. Prior to chemotherapy and radiation, the cells can be extracted, screened to remove cancerous cells, and frozen until they are needed. Another source is a donor, who can be a friend, a family member, or a complete stranger. Screening is conducted to find a donor who will be a good match, with the goal of reducing the risk of transplant rejection. The bone marrow stem cell transplant itself is a relatively quick procedure, it just requires a great deal of preparation and aftercare.
People who are interested in bone marrow stem cell transplant procedures can register as donors. Many nations have a bone marrow donor registry. To join the registry, people submit a blood sample and some basic biographical information. If someone needs marrow, the registry can be screened to see if any good candidates come up if there are no matches in the patient's immediately circle of family and friends. People always have the right to refuse to donate if contacted by a registry with a request for marrow.