The immune system- often regarded as the body’s defense system- fights the enemies (germs) which include viruses, bacteria, and other foreign bodies to protect the body from infections.
1.) Components of the immune system
a.) White blood cells (WBCs):
WBCs are the key players of the immune system. They defend the body against infection and disease by ingesting foreign materials and cellular debris. WBCs are of 3 major types- lymphocytes, monocytes, and granulocytes. Lymphocytes are responsible for the specific recognition of germs which are then targeted and destroyed. Monocytes cleanup the killed germs and remove the cellular debris from the site of infection. Granulocytes are key mediators of allergy and inflammation (swelling, pus formation, etc.)
The thymus gland is located behind the breastbone. It plays an important role in immunity, autoimmunity, and aging. It also produces white blood cells called T-cells.
Antibodies are protective proteins produced by the immune system in response to germs. Antibodies recognize and bind to the germs and kill them either by lysis, agglutination, or neutralizes the harmful effects of toxins.
Antibodies are produced by specialized WBCs called B-cells. When a germ binds to the B-cell surface it triggers it to multiply and synthesize antibodies in huge amounts in order to kill the germ.
d.) Complement system:
The complement system is a set of proteins working on germs to make them more susceptible to antibodies. Since it complements the action of antibodies, thereby the name.
e.) Lymphatic system:
The lymphatic system is a network of delicate tubes that runs parallel to arteries and veins. It is made up of lymph nodes (which trap microbes), lymph vessels (tubes that carry lymphatic fluid), and white blood cells. The lymphatic system is responsible for removing cellular waste, debris, and protecting the body from disease-causing microbes.
f.) Bone marrow& Spleen:
Bone marrow is the spongy tissue found inside your bones. The bone marrow is extremely important to the immune system because most of the WBCs (including T and B lymphocytes) originate in the bone marrow.
The spleen is a blood-filtering organ. It removes microbes and destroys old and damaged red blood cells.
2.) How does the Immune system function?
When the body comes in contact with foreign substances (called antigens), the immune system works to recognize the antigens and get rid of them.
B lymphocytes are triggered to make antibodies to destroy the germ. After their action, antibodies usually stay in our bodies in case we have to fight the same germ again. That’s why someone who gets sick with a disease, like chickenpox, usually won’t get sick from it again.
This is also how immunizations (vaccines) prevent some diseases. An immunization introduces the body to an antigen in a way that doesn’t make someone sick. But it does let the body make antibodies that will protect the person from future attack by the germ. T-cells, help B-cells in the destruction of germs. Antibodies also act by neutralizing toxins (poisonous or damaging substances) produced by different organisms. They also activate a group of proteins called complement that is part of the immune system. Complement helps kill bacteria, viruses, or infected cells.
These specialized cells and parts of the immune system offer body protection against disease. This protection is called immunity which protects our body from foreign invaders to keep us healthy.
Hope you liked this blog!
For more health related blogs, please click here.