About Bone Marrow Transplant and Donation
Here are my notes on Bone Marrow Donation which I wanted to share:
What is Bone Marrow?
Wiki: “Bone marrow (Latin: medulla ossium) is the flexible tissue found in the interior of bones. In humans, bone marrow in large bones produces new blood cells. On average, bone marrow constitutes 4% of the total body mass of humans; in adults weighing 65 kg (143 lbs), bone marrow accounts for approximately 2.6 kg (5.7 lbs). The hematopoietic compartment of bone marrow produces approximately 500 billion blood cells per day, which use the bone marrow vasculature as a conduit to the body’s systemic circulation. Bone marrow is also a key component of the lymphatic system, producing the lymphocytes that support the body’s immune system.”
So what is Bone Marrow? For me it is stuff which is found inside the bones, which produces new blood cells.
Some interesting facts:
- There are two types of Bone Marrow – Red Marrow and Yellow Marrow (made up of fat cells).
- Red Marrow produces – Red blood cells, platelets and white blood cells.
- At birth, all bone marrow is red.
- With age, more and more of it is converted to the yellow type; only around half of adult bone marrow is red.
- Red marrow is found mainly in the flat bones, such as the hip bone, breast bone, ribs, vertebrae and shoulder blades, and in the spongy material at the ends of long bones.
- Yellow marrow is found in the hollow interior of the middle portion of long bones.
- In cases of severe blood loss, the body can convert yellow marrow back to red marrow to increase blood cell production.
- There are blood vessels in bone marrow which acts as a barrier not allowing immature blood cells from escaping marrow and carries the mature blood cells.
- These blood vessels can also carry stem cells and may thus be harvested from blood (very important point, will explain the relation later).
So what exactly is bone marrow in one line – Its a nesting site for Blood and stem cells.
What are Stem Cells?
They are the Mother Blood Cells of the blood of human body and immune system. The Blood Stem Cells have the ability to become different types of blood cells (red blood cells, white blood cells, platelets). These Stem Cells are typically found in three places – Bone Marrow, the blood stream ( in smaller amounts) and Cord blood, the blood in the umbilical cord and placenta when a child is born. (Cord Blood Banking is gaining popularity and is on the rise now for unforeseen medical emergencies for any family member)
Why Bone Marrow Transplant?
In patients with leukemia, aplastic anemia, and some immune deficiency diseases, the stem cells in the bone marrow malfunction, producing an excessive number of defective or immature blood cells (in the case of leukemia) or low blood cell counts (in the case of aplastic anemia). The immature or defective blood cells interfere with the production of normal blood cells, accumulate in the bloodstream and may invade other tissues.
Large doses of chemotherapy and/or radiation are required to destroy the abnormal stem cells and abnormal blood cells. These therapies, however, not only kill the abnormal cells but can destroy normal cells found in the bone marrow as well. Similarly, aggressive chemotherapy used to treat some lymphomas and other cancers can destroy healthy bone marrow. A bone marrow transplant enables physicians to treat these diseases with aggressive chemotherapy and/or radiation by allowing replacement of the diseased or damaged bone marrow after the chemotherapy/radiation treatment.
What is Bone Marrow Transplant?
Bone Marrow containing normal stem cells is extracted from a healthy donor, and transferred into a recipient whose body cannot produce proper quantities of normal blood cells. The goal of the transplant is to rebuild the recipient’s blood cells and immune system and hopefully cure the underlying ailment.
Types of Transplant
There are three kinds of bone marrow transplants:
- Autologous bone marrow transplant: “Auto” means “self.” Stem cells are removed from you before you receive high-dose chemotherapy or radiation treatment. After these treatments are done, your stems cells are put back in your body. This is called a “rescue” transplant.
- Allogeneic bone marrow transplant: “Allo” means “other.” Stem cells are removed from another person, called a donor. Most times, the donor must have the same genetic makeup as the patient, so that their blood is a “match” to the patient. Special blood tests are done to determine if a donor is a good match for the patient. A brother or sister is most likely to be a good match. However, sometimes parents, children, and other relatives may be good matches. Donors who are not related to the patient may be found through national bone marrow registries.
- Umbilical cord blood transplant: Stem cells are removed from a newborn baby’s umbilical cord immediately after being born. The stem cells are stored until they are needed for a transplant. Umbilical cord blood cells are so immature, there is less of a concern that they will not match.
Now we know what Bone Marrow is, why Bone Marrow Transplantation is required, and the types of transplant. Lets look at the need of donor registry now.
Why Donor Registry is needed?
For the second form of transplant mentioned above we need donors, people who are ready to donate their blood stem cells. For a successful transplant, the patients’ genetic typing needs to closely match with that of the donor. Every patient has a 25% chance of finding a match within the family. However, 70% of the patients do not find a suitable donor within the family. In such cases, there is a need to find an unrelated donor or a cord, blood unit. Hence we need a database, a registry through which possible match can be found and people can be approached if they are ready to donate their blood stem cells.
There are over 50 donor registries & more than 13 million registered donors across the globe, with a very few Indians being a part of it. This reduces the chances of finding a possible match for a patient of Indian origin. India is in real need of a functional registry with donors belonging to diverse ethnic backgrounds. A patient is more likely to find a possible match within his/her race/ethnity, (i.e.) with people sharing the same cultural linguistic, biological traits etc.
Bone Marrow Donor Registries in India –
DATRI: – http://datriworld.org
Marrow Donor Registry India (MDRI): – www.mdrindia.org/
I am not sure if there are more registries in India, but these are the ones which I found.
Some of the other International Registries –
National Marrow Donor Program – http://marrow.org
Bone Marrow Donors Worldwide – http://www.bmdw.org/
Note that above links have wealth of information on Bone Marrow Donation.
Some quick FAQs –
Myths and Facts –
I am a registered Donor
How you can help?
Buccal Swab Sample – A quick and simple process, where a cotton swab is rubbed inside your cheek. It is later processed to determine your genetic typing.
Donate – In case of a successful genetic match, stem cells are obtained from you (donor) and injected into the patient’s blood stream.
What does Bone Marrow Registries do?
- Collect samples –Buccal Cells – A cotton swab is rubbed inside your cheek and the samples are collected.
- Process the Samples to analyze the DNA – Once a sample is collected, it is processed and a unique code is assigned to every sample.
- Database –The Genetic information of an individual obtained after thorough analysis is stored in a database.
- Search for a match –The patient’s tissue typing (genetic information) needs to match very closely with that of the donor, to enable a successful transplant.
- Transplant Process – DONOR: Once a match is found, stem cells are obtained from the donor. The process is usually as simple as drawing blood. PATIENT: The stem cells are then infused into the patient’s blood stream.
The procedure of donating
Bone Marrow: Once the donor is committed to donate, his/her bone marrow cells are harvested by giving general or regional anesthesia using a surgical process, with no pain during the process. Bone marrow is drawn from the hip bone to either side of the lower back with a special needle and a syringe. The amount of bone marrow drawn is only a small percentage of the total bone marrow and is typically replaced within four weeks. The donor remains at the hospital for 24-48 hours and can resume normal activities within a few days.
Peripheral Blood Stem Cells:
Peripheral blood stem cells (PBSC) obtained from circulating blood can also be used instead of bone marrow cells. The amount of stem cells found in the peripheral blood is much smaller than the amount of stem cells found in the bone marrow. In PBSC transplantation, blood is drawn from a vein from one arm and is passed through a machine that removes the blood-forming cells. Rest of the blood is returned through a vein into the other arm. The procedure to donate PBSC takes approximately 4-6 hours. There exist cases where a recipient cannot accept bone marrow stem cell transplants, but can accept PBSC transplants.
So what do you need to do?
- There is an immediate need to increase the database of people who can be possible donors. The process for the same is pretty straight forward. Approach to one of the registries, need to fill up a form, do a cheek swab and go home. It takes 10 minutes. I have done it myself.
- Later if a match is found, take a call if you want to go ahead with donation or else simply sit at home and watch a cricket match.
Two links I found where people have shared their experiences and views –
In the news – Mumbai: City gets its first bone marrow registry:
Salman Khan Fans – Salman Promotes Bone Marrow Donation