Major Histocompatibility Complex

The Major Histocompatibility Complex (MHC) is a group of molecules that are expressed on the surface of all nucleated cells and are essential to the proper functioning of both the innate and adaptive immune systems. MHC molecules interact with the receptors on T-cells and other immune cells, allowing for the recognition and destruction of foreign bodies, such as viruses, bacteria, and other foreign agents. MHC molecules are also essential for the detection of self-antigens, which enables the prevention of autoimmunity. Variation in MHC molecules underlie the rejection of grafts, as well as provide a degree of protection against infections, making them an incredibly important component of the immune system.