HLA Typing Improves Diagnosis and Treatment
Physicians diagnose thousands of people every year with leukemia, aplastic anemia, numerous cancers and other life-threatening diseases that require a bone marrow or blood (stem cell) transplant for survival. The success rate of bone marrow or peripheral blood stem cell transplants is dependent upon the "matching" of certain Human Leukocyte Antigens (HLA) antigens between the donor and recipient.
Human Leukocyte Antigens are proteins located on the surface of white blood cells and other tissues in the body. HLA antigens play an important role in the immune system’s defense against invaders such as bacteria, viruses and parasites. In transplantation, when the donor’s HLA is different from the recipient’s, the immune system of the recipient will recognize the donor's HLA antigens as foreign. This causes rejection of the transplanted tissue or organ.
The genetics involved can be complex, but the goal is to measure the number of "matching" antigens between the potential donor and the bone marrow transplant recipient. The closer the "match," the more likely the success of the transplant.
The Vascular Biology Laboratory at Franciscan Health Indianapolis, because of its commitment to antiphospholipid antibody research, routinely conducts the more complex tests for the antiphospholipid antibodies that escape detection using "kits." Comprehensive antiphospholipid antibody profiles are available to requesting physicians. Consultation and literature concerning test results are also available.
When is HLA typing used?
HLA typing is used to identify the best donor for a transplant recipient. In the best case scenario the donor will have the exact HLA antigens as the recipient. The risk of transplant rejection is lessened for well-matched donor-recipient pairs.
HLA typing is also used to help doctors distinguish diseases. Certain diseases are associated with particular HLA types. For example, a person with narcolepsy is likely to have HLA-DQ6 antigens. HLA typing can help a physician differentiate narcolepsy from other sleep disorders.
Requisitions for Testing
Do you have a patient who needs testing? Download a requisition form (see Related Resources below).
HLA and transplantation
The numerous possible variations and combinations of antigens make this a very specialized and sometimes difficult testing process. Finding a "match" within the family is much easier than finding an unrelated donor, because the number of possible combinations is limited to the family's genetic make-up. Each parent has only two copies of chromosome 6 to pass on to their children. For all children of the same parents there will be only four possible combinations of HLA antigens, genetic mutations such as crossovers and deletions, notwithstanding.
As part of the donor-recipient testing, once the antigen "match" has been established, Franciscan Health's HLA Vascular Biology Laboratory may perform a pre-transplant "crossmatch." The crossmatch is a test which determines if the recipient has an antibody to the donor's HLA antigens and vice versa (donor to recipient). This is different from the HLA typing and matching process. The crossmatch helps to predict the likelihood of an immune reaction between donor-recipient pairs as a positive crossmatch can lead to transplant rejection.
HLA and recurrent pregnancy loss
Recurrent miscarriages may be caused by maternal antibodies to the father's antigens. During pregnancy, these antibodies can attack a developing placenta resulting in a miscarriage.
The laboratory test used to detect maternal anti-paternal antibodies is a crossmatch like is done for transplant patients. In this case, the serum of the mother is reacted with the white blood cells of the father. Once identified, there are several treatment options for women with these antibodies.
About the HLA-Vascular Biology Laboratory at Franciscan Health
The HLA-Vascular Biology Laboratory at Franciscan Health Indianapolis is internationally recognized for its research and clinical testing expertise in the evolving relationship between disease and the presence of antiphospholipid antibodies.
- Molecular (DNA) HLA-A, -B, -C, -DR and -DQ low and high resolution typing
- Pre-transplant STR engraftment screen
- Post-transplant STR engraftment analyses
- PRA (panel reactive antibody) screen
- Flow cytometry crossmatch The HLA-Vascular Biology Laboratory performs state-of-the-art histocompatibility testing for Indiana Blood and Marrow Transplantation.
Licensure and Accreditation
The HLA-Vascular Biology Laboratory participates in the Proficiency Survey Programs of the American Society for Histocompatibility and Immunogentics (ASHI), the College of American Pathologists (CAP) and the UCLA International Cell Exchange.
The HLA-Vascular Biology Laboratory at Franciscan Health Indianapolis is accredited by The American Society for Histocompatibility and Immunogenetics (ASHI) for high complexity testing, the College of American Pathologists (CAP) for antiphospholipid antibody testing and maintains Clinical Laboratory Improvement Amendments (CLIA) certification. Our CLIA license permits intra- and interstate transit of blood samples.
- ASHI #: 02-4-IN-07-1
- CAP #: 1677706
- CLIA ID#: 15D0986138
- CLIA ID #: 15D1007375