The immune system is a collection of different body systems and cells that protect our body from bacterial and viral infection. This biological system identifies and attacks foreign cells and materials through specialized cells called B-cells. The immune system adapts over time to be able to quickly recognize and kill a virus or bacteria it has come into contact with before. This is called having immunity to a particular disease. Some disorders or diseases, such as AIDS, can lead to the immune system being less effective or not effective at all.
How Does The Immune System Protect Against Disease?
The immune system protects against disease through a series of steps called the immune response. The cells that are responsible for the body’s reaction to a disease are the white blood cells or leukocytes. There are two main types of these cells which play an important part in the protection of the body against disease. Leukocytes are stored and created in bone marrow, spleen and thymus. They are housed in the lymph nodes throughout the body. These leukocytes circulate around the body in the lymphatic vessel and blood vessels allowing them to seek out and protect the body from any disease that is present. The first types of Leukocytes called phagocytes are responsible for attacking and destroying the invading virus or bacteria. The second type of Leukocytes called lymphocytes recognize and remember invading virus and bacteria and help coordinate the body’s response to these organisms. Our immune system protects us from disease by first detecting and recognizing a foreign body or antigen. The B lymphocytes produce antibodies, which are special proteins designed to lock onto the antigen and neutralize it. Once the immune system has identified and destroyed an antigen the antibodies remain in the blood stream and protect the body against further invasion. This is how we become immune to disease.