Are you planning to undergo an organ transplant or want to better understand the role of your immune system?The HLA Typing test is a fundamental genetic screening that determines tissue compatibility between donor and recipient, helping reduce the risk of organ rejection. In addition to its vital role in the early diagnosis of immune-related diseases, HLA Typing is an indispensable step for accurately understanding your immune health.In this article from Dalili Medical, we review everything you need to know about HLA Typing: its importance, how it is performed, and when it is recommended.

What Is HLA Typing?

HLA Typing is a medical test used to determine the types and levels of Human Leukocyte Antigens (HLA) present in the body. These antigens are proteins found on the surface of the body's cells and play a critical role in the immune system's function by helping the body distinguish between its own cells and foreign or attacking cells.

HLA Typing is primarily used for tissue matching before organ transplantation to ensure compatibility and reduce the risk of organ rejection. It is also used in the diagnosis and monitoring of certain autoimmune and genetic diseases.

Importance of HLA Typing

Organ Transplant Compatibility

HLA is tested before transplant procedures such as kidney, liver, heart, or bone marrow transplants to ensure tissue compatibility between the donor and recipient, thereby reducing the chance of organ rejection.

Diagnosis of Autoimmune Diseases

Certain HLA types are associated with an increased risk of autoimmune diseases, including:

• Rheumatoid arthritis

• Psoriasis

• Celiac disease

• Multiple sclerosis

• Ankylosing spondylitis

Scientific Research and Immunotherapies

HLA Typing is used in research to develop personalized treatments based on the specific immune system profile.

How Is HLA Typing Performed?

1. Sample Collection: Usually, a simple blood sample is drawn from a vein. In rare cases, other types of cells may be sampled.

2. Laboratory Analysis: Advanced techniques are employed, such as:

   • Polymerase Chain Reaction (PCR)

   • Genetic sequencing

   • Microarray technologies

3. HLA Typing: The genetic types of HLA antigens carried by the cells are identified, including HLA-A, HLA-B, HLA-DR, among others.

Types of HLA Antigens

• HLA Class I (HLA-A, HLA-B, HLA-C):
  Found on the surface of all nucleated cells, they play a role in presenting antigens to natural killer (NK) cells and T cells.

• HLA Class II (HLA-DR, HLA-DQ, HLA-DP):
  Mainly present on immune system cells such as B cells and macrophages, and involved in activating T cells.

When Is HLA Typing Recommended?

• Prior to organ or bone marrow transplantation.

• For diagnosing certain autoimmune or inflammatory diseases.

• In cases of recurrent miscarriage in women.

• To determine donor compatibility in blood transfusion or tissue transplantation.

• In some immunology and genetic research studies.

How Do HLA Typing Results Help in Organ Transplants?

HLA Typing results assist doctors in:

• Selecting the most compatible donor for the patient.

• Reducing the risk of organ rejection.

• Planning appropriate immunosuppressive therapy.

• Monitoring the patient’s condition after transplantation.

Medical Interpretation of HLA Typing Results

• High compatibility between donor and recipient decreases the likelihood of rejection.

• Incompatibility or differences in certain HLA types increase the risk of transplant rejection.

• Some HLA types are linked to specific diseases and can be used as diagnostic markers.

Are There Any Risks Associated with HLA Typing?

No. HLA Typing usually involves only a blood draw, which is very safe and carries negligible risk.

Tips Before Undergoing HLA Typing

• Inform your doctor about any medications or existing health conditions.

• Have the test done in an accredited laboratory to ensure accuracy.

• Follow up with your specialist to understand your results and next steps.

Summary

HLA Typing is an important genetic test that plays a vital role in the success of organ transplantation and the diagnosis of autoimmune diseases. By accurately determining tissue compatibility, this test helps improve treatment outcomes and increases the chances of maintaining good health. If you are considering an organ transplant or suffering from an autoimmune condition, consult your doctor about undergoing this important test.