HLA - (Class II ) Typing

Human leukocyte antigens (HLA) are specialised proteins present on the surface of almost all cells except red blood cells (RBCs). HLA genes inherited by an individual are responsible for the HLA antigens in the cells. The HLA blood test identifies the significant HLA antigens on the surface of a person’s cells.

The test also identifies the antibodies to human leukocyte antigens and the genes responsible for the antigens to match transplant donors and recipients.

A special pattern of antigens is inherited from the parents. Half of this pattern comes from the mother and the other half from the father. These patterns are unique to every individual except identical twins who have the same pattern and are an identical match for tissue and blood cells. Siblings, especially sisters and brothers with the same parents, have a 1 in 4 chance of being an identical match.

The HLA genes are located in the chromosome 6 region called the major histocompatibility complex (MHC). It plays an essential role in the immune system management of the human body. For example, the MHC helps your body's immune system distinguish between cells that are self, foreign, or non-self. Cells recognised as non-self can activate an immune response, including the production of HLA antibodies.

With the help of an HLA blood test, you can find the pattern of antigens and subsequent HLA antibodies to the HLA antigens. If the HLA class II test result finds more antibodies, there is a higher likelihood of transplant failure. The HLA class II test result lets the doctors know whether there is a good match for a stem cell transplant.

Transplant rejection is one of the critical limiting factors for the success of solid organ transplantation. Various immunologic and non-immunologic factors determine it. Finding a donor who is compatible with a recipient can sometimes be challenging. This is because HLA genes can sometimes have multiple possible variations. This is referred to as polymorphic.

More than 200 genes comprise the HLA gene family, located on chromosome 6. Based on these numbers, there can be many different possible combinations and multiple types of HLA variations. Hence, finding a suitable donor can be challenging, especially if the recipient has pre-formed HLA antibodies.

At Apollo 24|7, you can get a Human Leukocyte Antigens (HLA) test to determine the following things:

• Detect the type of human leukocyte antigens 
• Detect HLA antibodies
• Identify the antigen types in blood donors to match transfusion recipients