The Nature of Blood Stem Cells and Marrow

Q: What are blood stem cells and why are they so vital?

A: Blood Stem Cells are the basic building blocks of our blood. They produce vital blood components, such as white cells which fight infection, red cells which carry oxygen, and platelets which prevent bruising and bleeding. Any disease that attacks your marrow, where your blood stem cells are most often located, may eliminate your body’s ability to protect itself. Most fatal blood diseases have traditionally been fought with radiation or chemotherapy. In countering disease, both forms of treatment may seriously damage the human body. By providing patients in need of compatible blood stem cells, you can give them a second chance at a healthy life. More than 20,000 marrow transplants have been performed worldwide.

Q: Where do you get blood stem cells?

A: Blood Stem Cells used in transplants can be found in your bone marrow, and to a much lesser extent in your circulating blood. They are also found in a baby’s umbilical cord blood.

Q: What is marrow?”

A: Marrow is soft spongy tissue found in the large bones of the body. It is very rich in stem cells and is primarily in charge of producing more blood stem cells that make the rest of your blood cells like red blood cells, white blood cells and platelets.

Blood Stem Cell Transplantation

Q: Who needs a marrow transplant?

A: Marrow transplantation is a proven cure for patients with aplastic anemia, some leukemias, lymphomas, and diseases of the immune system.

Q: Must donor and patient be related?

A: Initially, marrow donors were sought only among family members. However, approximately 70% of patients needing a transplant do not have a family member who is a compatible donor. Through HLA typing, non-related compatible donors can be identified and used successfully in a marrow transplant

Q: How is a donor matched to a patient?

A: When you register to become a donor, you provide a cheek swab sample. From that sample, we are able to obtain what is called your ’tissue type’ or your ‘HLA type’. This string of markers is what we use to match a patient to a donor.

Q: What is HLA?

A: HLA stands for Human Leukocyte Antigens, they are ‘markers’ on the white blood cells. These antigens are inherited characteristics, just as is the color of one’s eyes and hair or skin. In a tissue transplant, the closer the match in HLA type between the donor and the recipient, the greater the chance that the transplant will be successful. Due to these genetic factors, patients have the best chance of finding a donor who is the same racial background

Q: What are the odds of matching HLA types?

A: The odds of a siblings having identical tissue types are 1 in 4. The odds of matching an unrelated donor are between 1 in 100 and 1 in a million. Currently, only 25% of the National Registry represent the racial minority communities; therefore, the current odds for a minority patient to find a matching unrelated donor may be more close to 1 in a million. This is the reason for the current funding programs geared specifically to drastically increase the number of donors representing the ethnic minority communities.

Q: How do patients receive donated blood stem cells?

A: Patients receive donated blood stem cells much like a regular blood transfusion. The difference between the two is that before receiving the stem cells, a patient needs to undergo very intensive chemotherapy to wipe out his/her remaining marrow and immune system. Once the immune system is completely destroyed, the donor’s blood stem cells are administered like a blood transfusion. Then, if all goes well, the stem cells will make its way to the patient’s marrow and will start producing new stem cells.

The National Marrow Donor Program and the Asian American Donor Program

What is the National Marrow Donor Program?

The National Marrow Donor Program (NMDP) is a congressionally authorized nationwide computerized data bank of potential marrow donors. The NMDP network exists to match unrelated, informed donors with patients in need and to facilitate all unrelated marrow and blood stem cell transplants. Established in 1987, the NMDP is a collaborative effort of the American Association of Blood Banks and the Council of Community Blood Centers, operating with the funding from the National Heart, Lung, and Blood Institute of the National Institutes of Health and the Naval Medical Research and Development Command.

Who is the Asian American Donor Program and how are they related to the NMDP?

Who is the Asian American Donor Program and how are they related to the NMDP?”]AADP is a NMDP recruitment agency which provides education regarding the issue of unrelated marrow donation, and opportunities for the general public to participate on the National Registry. Due to the critical need for ethnic minority participation, AADP is funded by NMDP to encourage everyone, specifically the minority communities to be HLA-typed. AADP staff provide educational presentations and organize typing drives for universities, corporations, churches, community service groups, etc. AADP also provides assistance to minority patients in need to help get them access to culturally relevant services and materials.

Becoming a potential Marrow/Blood Stem Cell donor

How do you become a marrow donor?

Please visit our How to Become a Donor page. The first step to being a donor is to register to get on to the NMDP database of potential donors. First, a cheek swab sample is taken to determine your Human Leukocyte Antigen (HLA) type. The HLA type is listed in a computerized database, which is linked with the NMDP. If you are a potential match, you are contacted for additional blood tests. If laboratory tests reflect a potentially successful match, a detailed information session is arranged so that you can decide whether or not to proceed. If you decide to proceed, you are provided a full health screening before the actual marrow or PBSC collection

Why are younger donors preferred?

If you are between the ages of 18 and 44, patients especially need you. When more than one potential donor is a good HLA match for a patient, doctors will also consider other factors, including the donor’s age. Research shows that cells from younger donors lead to more successful transplants. That’s because younger donors produce more and higher-quality cells than older donors.

How do I register for the NMDP’s registry?

You can register by visiting one of AADP’s drives. Visit our Calendar for a listing of all our upcoming drives. When you come to register, please remember to bring your Driver’s License, Social Security No. or ID No. and the complete information of two contacts who do not live with you and who do not live with each other. If none of our drives are convenient for you, please contact us for a donor center near you that you can visit or for us to send you a mail-in registration kit.

What information do you need from me when I register?

What information do you need from me when I register?”]In order to register, we need a short health history, your Driver’s License No. or Social Security No. and the names, addresses and telephone numbers of two friends or relatives who do not live with you and who do not live with each other who may know how to contact you in future years in case you come up as a match. All information is STRICTLY confidential and extreme measures are taken to ensure this. Contacts you provide will not be contacted for any reason other than attempting to locate you should you come up as a match for someone and we are unable to reach you after several tries.

How much time does it take to become a donor?

How much time does it take to become a donor?”]The initial HLA typing will take approximately 15 minutes to complete. If you are a preliminary match, the high resolution typing will also require about 15 minutes. If you are determined to be a ‘miracle match’, the subsequent stages (confirmatory testing (CT), information session, health screening) will vary in time requirements, but the average time commitment is about 30 hours within 3 to 6 months. If you are concerned about work issues, there are resources in place to help you.

Do I have to pay to register?

The tissue typing process to register is currently completely funded for all people who have any ethnic minority descent. For the purposes of the NMDP, the category of Ethnic Minorities include anyone with some or complete heritage in the Asian and Pacific Islander, Hispanic/Latino, African American/African, and Native American groups. Because of the special need for more ethnically and racially diverse donors, most of our funds are directed specifically for registering people in this category. The category of ‘non-minority’ is used for people who’s tissue types are already well represented in the registry, and includes people of Caucasian, Middle Eastern, and North African descent. Sometimes, those in the ‘non-minority’ category may be asked to help cover the costs of their own tissue typing should they wish to join the registry.


When You Are Called As A Match

What is the Marrow Donation Process?

During a marrow donation, the stem cells are collected from the donor during a surgical procedure using a special needle inserted into the hip bone and NOT the spine. The procedure is usually performed as an outpatient service, but may require a donor to spend one night in the hospital. For a more detailed explanation, please visit our How to Become a Donor page.

What is the PBSC Donation Process?”

For four or five days before the PBSC donation, the donor is given an injection of a medication called Filgrastim to increase the number of stem cells released into the blood stream. After receiving the medication, peripheral blood stem cells can be collected through the process of apheresis. Donating PBSC is similar to donating platelets at a blood bank. The donor’s blood is removed through a sterile needle placed in a vein in one arm and passed through an apheresis machine that separates out the stem cells. The remaining blood, minus the stem cells, is returned to the donor through a sterile needle in the other arm.

What are the risks and complications for the donor?
There is a minor risk of infection where the needles were inserted into the pelvis, just as with any break in the skin. For Marrow donations, loss of blood may occur, but this is treated by transfusing the donor with his or her own previously collected blood. There are also risks associated with the anesthesia that is given before the marrow donation. All donors must pass a through physical examination and meet the standards of the anesthesiologist. For PBSC, there is a minor risk of infection at the needle insertion site, just as with any break in the skin and a minor risk of adverse effects to the Filgrastim that is given. All risks are minor and more than 98% of all donors do not experience any adverse effects.
Does it hurt?
Because anesthesia is used in marrow donation, you will feel no pain during the collection. Most donors experience soreness or tenderness in the lower back area for a few days or weeks after the collection. The sensation has been described as similar to the bruised felling one gets after falling on ice. For PBSC donation, most donors experience bone pain while receiving the Filgrastim. This pain typically disappears about one day after the blood stem cell donation.
Is the donor hospitalized? What is the recovery time?
For marrow, the donor enters the hospital the day before or the day of the donation. Donors sometimes stay in the hospital overnight, returning home the next day. Most donors are able to go to work the day after donation, and you may feel back tenderness anywhere 1 week to 4 weeks after donation. For PBSC, no hospitalization is required, and you are typically fully recovered the day after.
Who pays for the collection and other costs incurred?
All costs associated with the donation are covered by the patient’s health insurance. Donors are also automatically covered under a health insurance policy provided by the National Marrow Donor Program.
Am I obligated to donate? Can I change my mind?
You are never obligated to donate if you are called as a potential match. The entire process of donating your marrow or blood stem cells is completely voluntary. While you are always able to change your mind, it is important to know that if you are called as a match, and you have signed a ‘Consent to Participate’ form after your information session, the patient will begin preparation for the transplant. If you decide not to go through with the donation after signing this form, the patient will most likely die.
How many times can I donate?
Because your marrow and blood stem cells completely regenerate, you can technically donate several times in your life. It is rare to come up as a match for several people. You may never get called as a potential match or you might get called once or twice in your lifetime. Being a donor for someone does not stop you from donating to someone else in the future if the need arises. It also does not affect your ability to receive a transplant in the future should you need one. Your marrow takes approximately 4-6 weeks to completely regenrate itself and your blood stem cells after PBSC will normalize within 1-2 days after the donation.


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