Antigens, Self & Non-Self
- Every cell in the human body has markers on its surface that identify it
- Microorganisms, such as bacteria and viruses, also have their own unique markers
- These markers are called antigens and they allow cell-to-cell recognition
- Antigens are found on cell surface membranes, bacterial cell walls, or the surface of viruses
- Some glycolipids and glycoproteins on the outer surface of cell surface membranes act as antigens
- Antigens can be either self antigens or non-self antigens:
- Antigens produced by an organism's own body cells are self antigens
- Self antigens do not stimulate an immune response
- Antigens not produced by an organism’s own body cells, e.g. the antigens found on pathogenic bacteria and viruses, are non-self antigens
- Non-self antigens stimulate an immune response
- Antigens produced by an organism's own body cells are self antigens
