People tend to think of the immune system and its function in simplistic terms. They are likely to see it as being a single organ, even if they would not describe it exactly in those terms. Rather, the immune system is a complex system of cells, proteins, different organs and tissues which function together to prevent the proliferation of sickness and disease in the body. For example, white blood cells (leukocytes) help the body fight off foreign invaders. Phagocytes – a catchword for various types of cells, have their own way of fighting off foreign organisms.
When these foreign invaders (antigens) are identified by these components of the immune system, the aforementioned cells work together to produce antibodies. These antibodies are called proteins, which – along with something called T Cells – begin to deal with the invading antigens. These antibodies don’t normally go away. They stay in your body, and are there to deal with the invading antigen if they show up again months or years down the road. This is what helps keep you from getting repetitively sick from the same invading antigen. This whole process of protection from disease is what we all know as ‘immunity.’