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What is HLA?

HLA stands for human leukocyte antigens. HLA markers are proteins found on most cells in your body. Your immune system uses these proteins — or markers — to recognize which cells belong in your body and which do not. If an allogeneic transplant (which uses cells from a family member, unrelated donor or cord blood unit) is a treatment option, your doctor will take a blood sample to test for your HLA type. Your doctor will search for a donor or cord blood unit with an HLA type that closely matches yours.

How can I get my HLA typing results?

Ask your doctor for a copy of your HLA typing lab report. You may also want to ask your doctor to show you how to read the report.

If you have not been tested for your HLA type, talk with your doctor. Ask your doctor if an allogeneic transplant is a treatment option for you. If a transplant is an option, it is a good idea to see a transplant doctor (have a consultation) early after your diagnosis. Your first treatment may not be a transplant, but a transplant doctor can help you and your primary doctor look at all your treatment options and plan ahead.

What is a match?

A match is a donor or cord blood unit with specific HLA markers that are the same as yours. Research has found that a small number of HLA markers are most important to transplant outcomes. These are the markers transplant doctors look at when they match donors with patients. The best available donor or cord blood unit may match you at all or at most of the HLA markers your doctor looks at. Many patients who receive an unrelated donor transplant have a partially matched donor or cord blood unit.

A well-matched donor or cord blood unit is important for your transplant, but it is only one of the things that can affect your outcome. For cord blood transplants, the number of blood-forming cells in the cord blood unit is important. Your disease, the stage of your disease, your age and general health can all affect how well you will do. Doctors will consider all these things when making decisions about a transplant.

Your MatchView results

Why are these donors called potential matches?

The matches listed in your results are called potential matches because more information is needed to find out if the donors or cord blood units are suitable and available. Historically, donors have been typed at a basic level for 6 HLA markers when they join the Be The Match Registry,® operated by the National Marrow Donor Program® (NMDP). This is the minimum HLA information that transplant centers need to start a donor search. However, transplant centers will need more details to find the best available donor or cord blood unit.

If you need an unrelated donor or cord blood transplant, your primary doctor will refer you to a transplant center for a consultation. A transplant center will look at the best potential donors and/or cord blood units and ask for more testing at a high level of detail. This is called a formal search.

Further testing may show that some donors do not match at a detailed level, or at all the markers your center requires. In addition, some donors or cord blood units may not be available. For example, a donor’s health may have changed, making him or her unable to donate.

Transplant centers also look at other factors, such as the age of adult donors. For cord blood transplants, the number of blood-forming cells in a cord blood unit is important. The number of blood-forming cells needs to be suitable for the size of the patient — larger patients need more cells. The transplant center wants to make sure you receive the best possible donor or cord blood unit for you.

Do my results include all potential donors in the world?

No. MatchView shows you potential matches on the Be The Match Registry at the moment you use the tool. The registry includes more than 10.5 million potential adult donors and nearly 185,000 umbilical cord blood units. It is updated constantly as new donors and cord blood units are added and others are removed. Be The Match is operated by the National Marrow Donor Program (NMDP).

There are also other donor registries and cord blood banks. When your doctor conducts a search through the National Marrow Donor Program, he or she can search more than 20.5 million potential donors and more than 590,000 cord blood units on U.S. and global registries, including the Be The Match Registry.

What is an 8 of 8 match? Why does MatchView include only 8 markers if a transplant center looks at more? 

An 8 of 8 match is a donor that matches you at 8 HLA markers: two A, two B, two C, and two DRB1.

MatchView looks at these 8 markers based on minimum matching requirements. Before a donor can be considered for use in a transplant, a match of at least 6 of these 8 markers is required. For cord blood units — which require less stringent matching criteria — a match of at least 4 of 6 markers (HLA markers at A, B, and DRB1 only) is required. These minimum requirements are based on research studies of transplant outcomes and align with current clinical practice.

To select the best available donor or cord blood unit, a transplant center will look at more detailed information. For most centers, this includes looking at more than 8 HLA markers (many also look at DQB1). A transplant center will ask for additional testing to find a donor or cord blood unit that matches you at a detailed level.

What if I have few or no 8 of 8 donor or 6 of 6 cord blood blood unit matches?

If your results here show few matches, this does not rule out a transplant for you. Talk with your doctor about your results. If an unrelated donor transplant is a treatment option, your primary doctor will refer you to a transplant center. The transplant center will work with the NMDP to conduct a worldwide search for the best available donor or cord blood unit. Your center may find a suitable donor on another registry or among the new donors and cord blood units added to the Be The Match Registry every day.

It is also important to remember that the level of matching is only one of the things that affects your chances of having a successful transplant. Many patients who receive unrelated donor transplants have a partially matched donor or cord blood unit. Your disease, the stage of your disease, your age and your general health all can affect how you respond to a transplant. Your doctor will consider all these things when making decisions about a transplant.

The search for a donor or cord blood unit

How do I find a donor or cord blood unit for my transplant?

You are not responsible for finding your own donor. If you need an unrelated donor or cord blood transplant, your primary doctor will refer you to a transplant center. Your transplant center will work with the NMDP to find a donor or cord blood unit for you.

In general, we encourage patients and their immediate families to focus their energies on caring for the patient. Our ongoing recruitment efforts add more than 52,000 new donors to the registry each month. However, some families want to get involved in recruiting donors to the Be The Match Registry. If you want to raise awareness about the need for donors, we can help you.

How does a transplant center choose the best donor or cord blood unit for me?

After your primary doctor refers you to a transplant center, your transplant center will work with the NMDP to find a donor or cord blood unit for you. Your transplant center will request more tests to see if a potential donor or cord blood unit is a suitable match. Sometimes more testing shows that potential donors or cord blood units do not match you at all the details or markers your center requires.

Your transplant center will also look at other information. For cord blood transplants, the number of blood-forming cells in a cord blood unit is an important consideration for transplant physicians when selecting a unit. Adults and larger adolescents can undergo cord blood transplantation. If a single cord blood unit does not contain an adequate number of cells, then a transplant physician may consider a transplant using more than one unit. In this case, a patient can receive two cord blood units to ensure there are enough blood-forming cells.

Why do my results show a different number of potential matches than my transplant center says I have?

If you have already been referred to a transplant center, your transplant team will have details about your potential matches. Your transplant center can give you the most accurate number of potential donors and cord blood units for you. Some reasons your transplant center may report a different number of potential donors and cord blood units than appear in your MatchView results include:

  • MatchView shows only donors and cord blood units on the Be The Match Registry. When your transplant center conducts a search through the NMDP, it has access to additional donors and cord blood units from registries worldwide.
  • Some of the potential donors and cord blood units in your MatchView results may not meet the requirements of your transplant center.
  • Some potential donors or cord blood units in your MatchView results may not be available. For example, a potential donor’s health may have changed, making him or her unable to donate.

How long will it take to find a donor or cord blood unit for my transplant?

Your transplant team will work with the NMDP to conduct a worldwide search to find you the best available donor or cord blood unit. This can take as little as 2 weeks to as long as 2 months or more. Cord blood units are stored and ready to use, so if you need a transplant quickly, your doctor may consider using cord blood. Sometimes no suitable match can be found. If that happens, your doctor will look at other treatment options.

Starting the donor search early may improve your chances of getting a transplant when you need one. If a transplant is an option for you, it is a good idea for your primary doctor to refer you to a transplant doctor for a consultation early after your diagnosis. A transplant doctor can work with your primary doctor to find the best time for a possible transplant and to plan early treatments that will not rule out a transplant later.

Next steps

What can I do with these results?

Print your results and bring them to your doctor. You can use them as a resource to talk about whether a transplant is a treatment option. If an unrelated donor or cord blood transplant is an option, your primary doctor will refer you to a transplant center. There are 174 transplant centers in the United States as well as international transplant centers where you may be able to receive an unrelated donor transplant. For transplant center information, see Choosing a transplant center

What if I don't understand my results?

We are here to help. If you have questions about your MatchView results, the search and transplant process or finding a transplant center, contact Be The Match Patient Services. Our patient services coordinators are available Monday - Friday, 8 a.m. to 5 p.m. U.S. Central time.

  • In the United States, call 1 (888) 999-6743. This call is toll-free.
  • Outside the United States, call 001 (612) 362-3410. This call may have long-distance or international charges. 

You can also send an e-mail message to: patientinfo@nmdp.org

For questions about how a transplant fits into your treatment plan, talk to your doctor.

If you already have a search in progress, your transplant center has the most complete information about the status of your search. If you don’t know who to talk to at your transplant center, or you need help in a language other than English, you can contact Be The Match Patient Services.