Each year in Canada, hundreds of individuals require a stem cell transplant to help them fight a serious illness, often cancer. What are stem cells, who needs them, and who can donate them? Read on!
The role of stem cells
Stem cells are undeveloped cells that have the ability to grow into specialized cells like red blood cells, white blood cells and platelets. They are produced in the bone marrow, the core part of our bones. Some stem cells develop into mature blood cells and leave the bone marrow in order to enter the blood stream. Others develop into specialized cells that the body can use to rebuild or repair damaged tissue. The blood contained in a newborn baby’s umbilical cord also contains stem cells that can be donated to an individual in need.
Who needs stem cells?
People may require a stem cell transplant if their bone marrow or the stem cells it produces are damaged by a disease or medical treatment. Leukemia, a cancer of the blood, is often a cause of bone marrow damage. Some cancer treatments can also kill stem cells at the same time as they kill cancer cells.
When someone needs a stem cell treatment, the first step is to find a compatible donor. In addition to having the same blood type, the donor must also have sufficient markers of a system called HLA in order to be considered compatible. These markers are very numerous and complex, making it difficult to find a compatible donor, even within the person’s immediate family. This compatibility is essential for the transplant to succeed. If the match isn’t perfect, the recipient’s body will reject the donor’s stem cells.
When family members are not sufficiently compatible, we must turn to complete strangers who have taken the step of registering on stem cell donor registries. Given the complexity of finding a compatible donor, it isn’t unusual to have to turn to other countries with registries before a donor can be found. Even though the individual with the illness may live in Quebec, the stem cell donation may end up coming from another country, or even another continent!
For the past few years, Héma-Québec has also been maintaining a blood bank taken from umbilical cords. If the mother agrees to make the donation, blood is taken from the baby’s umbilical cord right after birth, when the cord connecting mother and child is cut. The blood is frozen and can be stored for 10 or more years while waiting for a compatible recipient to need it.
Even when the perfect match is found, transplanted stem cells are still “foreign”. Recipients must therefore take anti-rejection drugs in order to prevent their body from destroying these foreign cells.
In some cases, the sick person’s bone marrow was healthy, but an aggressive medical treatment (e.g. a cancer treatment) could end up destroying it. In these cases, it may be possible to remove the person’s stem cells before beginning the treatment, and then reintroduce them after the treatment is completed. This is called an autologous transplantation. Since the stem cells come from the person’s own body, no anti-rejection drugs will be required.
Who can donate stem cells?
In Quebec, the first step is to register with Héma-Québec. Applicants must be between the ages of 18 and 35 at the time of registration, be in good health and willing to donate stem cells if contacted for this purpose at a later date. Once registered, individuals may be contacted up to the age of 60.
Héma-Québec contacts every person who applies for the registry in order to provide all the information they need to make an informed decision regarding their registration.
The likelihood of being contacted is quite low and donors still have the option of changing their mind about donating if ever they are contacted. However, once a good match is established, if compatible donors agree to proceed, they must then go through with the whole process.
The reason for this is that once a compatible donor is found and has agreed to proceed, the recipient then begins to undergo a treatment that kills stem cells and destroys the immune system. Since the immune system is responsible for combatting infections, the recipient must be placed in isolation because even a common cold could prove fatal. The recipient’s survival depends on protective measures taken by the medical team, but also on the stem cell transplant that will help rebuild the person’s immune system.
Finding a compatible donor is like looking for a needle in a haystack. The more people get listed on Héma-Québec’s registry, the greater the odds of finding THE person who can save a person in need, here or elsewhere in the world. Are you ready to register? Visit the Héma-Québec website!