Steps: Searching for Unrelated Hematopoietic Cells

As a payor, it is important to understand the difference between a preliminary search and a formal search because:

Insurance coverage must be verified before a formal search can be conducted.
A delay in proceeding to a formal search could prevent the patient from receiving a transplant or limit the success of the transplant outcome.

1. Request a preliminary search

A preliminary search for potentially matched donors and cord blood units can be done early, while developing a treatment plan or initiating other treatments.

A preliminary search:

Lists the potential donors and cord blood units that may closely match the human leukocyte antigen (HLA) type of the patient at that specific time
Helps HLA experts and physicians assess the potential challenges of identifying closely matched unrelated hematopoietic cells

Results of a preliminary search are available in one business day or less. A preliminary search:

Is free
Can be requested by any physician or transplant center
Can be repeated at any time, at no cost

Every day donors are added to the NMDP Registry. A preliminary search looks at the donors and cord blood units on the NMDP Registry—at that moment, on that day. To identify the best matched donor or cord blood unit, a formal search must be activated.

Every search through the National Marrow Donor Program (NMDP) Registry uses HapLogic^SM, a matching algorithm. HapLogic uses advanced logic to predict a match based on the analyses of thousands of donors on the NMDP Registry. Using HapLogic, each search report indicates the donors or cord blood units that may closely match the patient’s tissue type.

2. Conduct a formal search to identify the best unrelated hematopoietic cells for the patient

After insurance coverage is verified and a caregiver is identified, the transplant center's HLA expert activates a formal search by HLA testing specific donors and cord blood units identified through a preliminary search. HLA testing helps the physician identify the best hematopoietic cells for the patient.

The search for a donor or cord blood unit can take weeks or months. Factors affecting the amount of time include possible HLA challenges of the patient. Patients with an uncommon or challenging HLA type, such as patients from certain racial and ethnic backgrounds, can require extensive HLA testing to identify the best match for the patient.

HLA testing

A formal search requires:

HLA tissue typing at A, B, C and DRB1 to find a close match
Confirmatory testing to verify the HLA of the donor or cord blood unit and identify the best HLA match for the patient
Infectious disease marker (IDM) testing to identify diseases that could be transmitted through blood

Depending upon the requirements of the transplant center and the HLA challenges of the patient, a formal search may also include:

HLA tissue typing at DRB3, DRB4, DRB5, DPB1 and DQB1

After selecting the best choice

Using HLA testing and other factors, the physician selects the best donor or cord blood unit for the patient.

If a donor is selected, donor workup begins.
If a cord blood unit is selected:
- The physician may determine that more than one cord blood unit is needed. This decision depends upon the size of the patient and the cell dose (the number of stem cells) in the cord blood unit.
- The cord blood unit is confirmatory typed and requested from the cord blood bank.

More information:

Formal search: HLA tests for donors and cord blood units

3. Workup the donor or request the cord blood unit

Donor workup ensures the safety of the donor and the patient. The donor:

Attends an informational session to learn more about the donation process and signs a document indicating his or her consent to donate.
Receives a physical exam to ensure that he or she is healthy enough to donate.
Provides a fresh blood sample to repeat IDM testing and perform any additional tests required by the transplant center. (Several months may have elapsed from the initial IDM testing; a second test ensures patient safety.)

A cord blood unit is already collected and is stored frozen at a public cord blood bank. After confirmatory typing, the cord blood unit is delivered to the patient's transplant center.