Definition

A type of molecule found on the surface of most cells in the body. Human lymphocyte antigens play an important part in the body’s immune response to foreign substances. They make up a person’s tissue type, which varies from person to person. Human lymphocyte antigen tests are done before a donor stem cell or organ transplant, to find out if tissues match between the donor and the person receiving the transplant. Also called HLA and human leukocyte antigen.