Human leukocyte antigens (HLA) are related to a series of genes that regulate the immune system. Proteins encoded in genetic cells are known as antigens, which play a critical role in organ transplants and matching donors and recipients. Antigens act as defenses against disease and can affect autoimmune diseases. The HLA system can also determine a person's particular scent and influence the selection of a mate for reproduction.
This system represents the major histocompatibility complex in humans, meaning they have the same or most of the same sets of genes. Genes found on chromosome 6 make up the human leukocyte system, which encodes cellular molecules that provide immune benefits to T cells in the body. Finding two unrelated people with the same HLA molecules in this location is extremely rare.
The human leukocyte antigen system was discovered by researchers looking for ways to transplant organs from one individual to another. They discovered that the white blood cells of the immune system create antibodies to fight off exposure to infection. When a foreign antigen is introduced through organ transplants, the body's immune system attacks the donor tissue if it is not compatible with the genes of both the donor and the recipient of the organ or tissue. Surgeons perform human leukocyte antigen tests to find similar HLAs to decrease the chance of organ rejection.
The human leukocyte antigen test compares samples from potential donors with antigens found on the recipient. This evaluation, along with blood typing, is done for transplants that include kidney, bone marrow, and liver. The greater the number of identical HLA antigens in both people, the greater the chance that the transplant will be successful.
The antigen test is also done during paternity tests. The HLA antigens of the named father, mother, and child are compared for similarities after a blood sample is obtained from all three. If a child produces antigens that are not present in adults, the alleged father can be excluded as a father.
HLA types are inherited at six points on chromosome 6, and some of them are linked to autoimmune disorders and other conditions. A person who inherits specific antigens from their parents is more likely to develop diseases such as diabetes and lupus. Cancer and hereditary diseases are also linked through the human leukocyte antigen systems, meaning doctors can now attack abnormal cells before they develop into a cancerous state.