Opening a door, cruising the internet on your phone or laptop, working out in the gym – pretty much doesn't matter where you go or what you do – you're being exposed to germs and bacteria. This is where our immune system steps in to protect us, and if we're lucky enough to have a strong one that's in good shape, it will fight off any bugs and diseases that would make us sick.
The immune system is composed of special cells, proteins, tissues and organs which together are capable to mount a well orchestrated attack on any germs that try and invade the body. Your body's immune system is pretty complicated and sometimes things can go wrong. When this happens, chances are you will be exposed to microorganisms that can result in infection and any kind of illness.
The cells that form part of your immune system are white blood cells or leukocytes. These cells will seek out and destroy organisms that cause disease and they are produced and stockpiled away in multiple spots throughout your body. These storage areas, called the lymphoid organs, include the spleen, thymus and bone marrow.
Leukocytes constantly circulate throughout your body and are always on the lookout for any germs or substances that might cause harm.
There are two basic types of leukocytes:
phagocytes are cells that destroy invading organismslymphocytes are cells that ensures the body remembers and recognizes previous invaders and assists the body in destroying them
Of the phagocytes, one of the most common types is the neutrophil cells. Their first and foremost job is to fight bacteria. If a blood test were to show that a patient had a heightened level of neutrophil cells, chances are these have been generated in response to a bacterial infection and the number of these neutrophils would give the doctor an indication of the severity and seriousness of the infection.
Of the lymphocytes, there are two main kinds; either B lymphocytes or T lymphocytes. Lymphocyte cells begin in the bone marrow and will either stay there and become B cells, or move on to the thymus gland and develop into T cells.
Each of these B and T cells have different jobs to do. The B cells can be thought of as your body's intelligence system, identifying threats and sending out defenses to block them and protect you. The T cells on the other hand, based on the intelligence of the B cells, will actually find and destroy the germ and bacterial trespassers.
The name for any foreign substance that invades the body is antigen. There are a number of different types of cells that work as a team to recognize and respond and these cells will prompt the B lymphocytes to produce antibodies. These antibodies are dedicated proteins that lock onto specific antigens.
When the intelligent B cells identify a repeat antigen, they immediately produce the correct antibodies. This is why people frequently won't get sick from the same disease, once they've had it. This is also why immunizing against certain diseases works so well. The immunization introduces an antigen to the body in a way that doesn't make the person sick but it does stimulate the immune system to produce antibodies that will protect against future harm.
Although antibodies can recognize an antigen and lock onto it, they are not capable of destroying it without help. That is the job of the T cells. The T cells are part of the system that destroys antigens that have been identified by antibodies or cells that have been infected or somehow changed. There are actually T cells that are called “killer cells.”
Antibodies can also neutralize toxins produced by different organisms. Lastly, antibodies can activate a group of proteins called complement that are also part of the immune system. Complement assists in killing bacteria, viruses, or infected cells.
It's clear that the immune system's response to a threat is an integrated and complicated one. Strong immune systems lead to better health and compromised immune systems allow for more disease and ailments. Supporting and protecting your immune system is critical for optimal health.