What is the immune system?
The immune system is the body’s natural defense system to help fight infections and other diseases.1 Its job is to prevent or limit infections by recognizing and destroying foreign substances known as pathogens such as bacteria and viruses and abnormal or unhealthy cells such as cancer cells.2 When the immune system is defending the body against infection and disease, it is called the immune response.2
The immune system is made up of a complex network of different organs, special cells, and substances that work together to protect the body and respond to infection and disease.2 We can describe the immune system as an army. It has many different kinds of “soldiers”, all with different functions that work together to protect the body. Some of these soldiers recognize the unhealthy cells, others communicate with other cells or tissues in the body, while others are the fighters that attack and destroy the enemy.
The components of the immune system consist of
cells, tissues and organs including:
Blood Cells
White blood cells called lymphocytes are part of the immune system. They are produced in the bone marrow. Main types of lymphocytes are: 2
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(also called B lymphocytes)
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(also called T lymphocytes)
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(also called NK-cells)
The immune system is essential for our survival. Without an immune system, our body would be exposed to a world full of dangerous microbes. It is our immune system that keeps us healthy as we drift through a sea of pathogens.