In the medical drama Grey’s Anatomy, Surgical resident Izzy agrees to donate bone marrow. In a scene that probably gave donation professionals goosebumps, Izzy grimaced on the operating table as the doctor inserts a needle into her thigh and twists it aggressively.
In real life, doctors designed bone marrow donation to be as painless as possible. Most donors provide stem cells that are collected from the bloodstream before the blood is returned to the body. And those who donate directly from the bone are under full anesthesia, not clutching a pillow like poor Izzy.
Advocates urge more people — especially people of color — to join bone marrow registries to help 18,000 patients each year who are diagnosed with blood disorders and need donated stem cells.
Bone marrow benefit
A bone marrow transplant (BMT) takes a donor’s healthy stem cells and gives them to a patient so they can grow their own healthy red blood cells, white blood cells and platelets.
It’s BMT used to help people who have blood cancers, including leukemia and lymphoma. BMT also treats different life-threatening conditionsincluding sickle cell disease, bone marrow disorders and inherited metabolic disorders.
There are several different types of BMT. The first one, autologous, collects the cells from the patient’s own bloodstream. This method has several advantages, including not having to look for a donor. The patient should also not be immunosuppressed. There are disadvantages, including a higher risk of relapse.
The second type, an allogeneic hematopoietic stem cell transplant (HSCT), is more common and involves finding a donation from another person. The patient’s siblings are usually approached first. Full biological siblings have 25 percent chance of a perfect match. Medical teams usually turn to donor registries when a family member is not a match. About 70 percent of patients do not have a match in their family and need help from an unrelated donor.
Collection of healing cells
The process of unrelated donation begins when a person registers with a registry such as Be the match. They receive a kit in the mail that includes a cotton swab to collect cells from the inside of their cheeks. When the kit is returned, the lab looks for a specific protein, human leukocyte antigens (HLA).
If a person is suitable, their doctor will decide which type of harvesting process is best. Historical, blood stem cells were harvested from the bone marrow. In this process, the donor lies on their stomach so that the doctor can insert a needle into the iliac crest, located at the back of the pelvic bone.
Depending on the concentration of stem cells in the bone marrow, the donor would give between 0.5 and 1.5 liters of bone marrow. This all happens under general anesthesia, and the donor usually spends one to two nights in a hospital for observation. They may temporarily experience pain or bruising.
The second and more common option is to take stem cells from the donor’s blood. The process begins a few days before donation, when the donor is injected with granulocyte-colony-stimulating factor to increase the movement of stem cells from the bone marrow into the bloodstream.
The donation process is somewhat similar to donating platelets in a blood donation. The donor’s blood is drawn from a vein in the arm and travels through a tube into an apheresis machine, removing the stem cells and returning the blood to the donor. The process takes two to three hours and is performed on an outpatient basis. Donation may require two to three sessions, and donors report no pain, although the growth factor may cause temporary headaches, joint or bone pain.
Various donors are needed
In addition to being included in a bone marrow registry, parents can donate the blood from their newborn’s umbilical cord and part of the child’s placenta. Stem cells from both are kept in the repository until there is a match in the registry.
| More ▼ over 805,000 units of umbilical cord blood are stored worldwide and about 39 million potential donors have registered in registries. That might seem like enough, but advocates say more variety is needed.
Bone marrow donations are matches based on HLA markers, which are inherited. Patients are more likely to match a donor who has a similar ethnic background. Problematically, fewer donors of color have signed up to registries and patients of color are less likely to find a match.
White patients e.g. have 79 percent chance of finding a match based on their ethnicity. For Indians, the probability drops to 60 percent. The odds drop to 48 percent for Hispanics or Hispanics and 47 percent for Asians and Pacific Islanders. For black Americans, the odds of finding a match are 29 percent.
Potential donors who want to join a registry can do so for free by requesting a cheek swab kit from an organization such as Be the matchwhich is implemented through the National Bone Marrow Donation Program.