Autoantigens, also called MHC proteins (major histocompatibility complex), are a set of cellular membrane proteins, specific to each individual. They assume a "molecular identity card", which makes it possible for the cells of our immune system to recognize our cells as their own and not attack them. In our species, autoantigens are synthesized from a set of genes located on chromosome 6, which is called MHC (major histocompatibility complex). Only when the autoantigen is abnormal (is the case of many tumor cells), or is associated with a foreign antigen, the carrier cell will be attacked by the cells of the immune system.
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