For some people with blood cancer, a stem cell transplant is their only chance at survival. It gives their body a reset so they can start making healthy blood cells again after treatment.
When the stem cells come from another person, doctors call it an allogeneic stem cell transplant. The name sounds intense, but the idea is straightforward. A healthy donor’s stem cells replace the damaged ones in the patient’s body so their immune system can rebuild and recover.
Trace Richey during his stem cell transplant at St Vincent’s Hospital, supported by the nurses who stood beside him every step of the way.
How stem cells work
Stem cells are the body’s raw materials. Blood stem cells live in our bone marrow and create red cells for oxygen, white cells that fight infection, and platelets that help blood clot.
When someone develops blood cancer or a serious blood disorder, their bone marrow can slow down or stop making healthy blood cells. When that happens, even a small infection can hit hard. A stem cell transplant helps the body start producing healthy cells again so the person has a fighting chance.
The role of a donor
In an allogeneic transplant, the healthy stem cells come from someone else. The donor needs a tissue type that closely matches the patient’s. Doctors check something called Human Leukocyte Antigens, or HLA markers, which act like your body’s internal ID.
A close match gives the new stem cells the best chance of settling in and doing their job. There is roughly a one in four chance a brother or sister will be a match. When there is no matching sibling, doctors search the Australian and international stem cell donor registries to find someone who can help. We call them Legends!
How donated stem cells are collected
Most donations in Australia come from the blood rather than the bone marrow. Doctors call this method Peripheral Blood Stem Cell collection.
Before donating, the donor receives four daily injections of a natural hormone called G CSF. This encourages the bone marrow to create more blood stem cells and release them into the bloodstream. On the fifth day, very similar to a plasma donation, the donor’s blood flows through a machine that separates out the stem cells and returns everything else to the donor.
The whole process takes four to six hours. Most donors go home afterwards, grab a snack, and say the experience was way easier than they expected.
In some situations, doctors collect stem cells directly from the bone marrow while the donor is under general anaesthetic. They only choose this method if it gives the patient a better outcome. Donors might feel a little tender afterwards, but the soreness usually settles after a few days.
While both donation types are safe, the donor always has the choice.
What happens during a transplant
Before the patient receives the donated stem cells, they have high dose chemotherapy or sometimes radiation therapy. This clears out the unhealthy cells and creates room for the new stem cells to grow.
The donated stem cells then go in through a drip into the patient’s bloodstream, similar to a blood transfusion. Once inside the body, the stem cells travel to the bone marrow and start creating healthy new blood cells.
This phase is called engraftment and it can take a few weeks. During this time, the patient stays in hospital while their medical team monitors their progress and supports their immune system as it slowly rebuilds.
Life after a transplant
Recovery after an allogeneic stem cell transplant is serious work and the patient needs strong medical support. Their immune system stays vulnerable until the new cells grow, so the risk of infection remains high.
Doctors carefully watch for a condition called graft versus host disease. This happens when the new donor cells react to the patient’s tissues. It can be mild or more serious, but treatments continue to improve every year. A close HLA match helps lower the risk.
Many patients go on to live long, healthy lives. Donor stem cells give them a real chance to recover, which is why every new donor matters.
Why more donors are needed
More than a thousand Australians need a stem cell transplant each year. Even with that demand, over 85 percent of stem cells used for Australian patients still come from overseas donors. A patient’s chance of finding a match depends on who has signed up to the registry, not just here but around the world.
Because HLA markers are inherited, the best match often comes from someone with the same ancestry. That is why Australia needs more young donors from many different cultural backgrounds. Every community that joins increases the chance of finding a match for someone who desperately needs one.
If more young Australians from different backgrounds join the registry, we can build a stronger and more diverse donor pool here at home.
How you can help
If you’re aged between 18 and 35, you can join the Australian stem cell donor registry through Stem Cell Donors Australia.
It only takes a few minutes to sign up online and a cheek swab kit will be mailed to you.
You might never get called, but if you do, it means your stem cells are the match someone has been waiting for.
Be a legend, save a life.
Start the sign up process here.
References
• TLR Foundation — Become a Stem Cell Donor
• Stem Cell Donors Australia — Why Stem Cell Transplants
• Cancer Australia — Stem Cell Transplants