Human leukocyte antigen, HLA

These are proteins found on the surface of many cells in the body. There are two main complexes of tissue compatibility in this system: MHC-1 and MHC-2 (Latin major histocompatibility complex). All cells except erythrocytes have MHC-1 antigens. MHC-2 is present only in immune system cells (B lymphocytes, certain T lymphocytes, phagocytes). When blood is transfused, donor leukocytes and platelets, MHC-1 antigens can cause a reaction of intolerance. This is important for the tissue transplant process.

Source | Glossary of Most Commonly Used Biomedical Terms and Concepts | Lithuanian University of Health Sciences | Academician Professor Antanas Praškevičius, Professor Laima Ivanovienė