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About the Immune System
Can You Explain the Immune System to Me?+
The immune system is made up of organs and cells in the body that all work together to fight infections. The immune system is also responsible for inflammation. Below are some of the common cells that make up the immune system:
White blood cells
Your body makes white blood cells to fight infections. White blood cells fight infections by producing antibodies. Antibodies also cause inflammation.
RA involves two types of white blood cells:
- B cells: B cells make a substance called rheumatoid factor (RF). RF is an antibody that helps fight infections. In RA, B cells produce too much RF and don’t work properly.
- T cells: T cells are important for fighting infections. There are different kinds of T cells, and some cause inflammation. In RA, the immune system produces too many of the T cells that cause inflammation.
Cytokines are messengers that tell the immune system what to do when fighting an infection. Sometimes these messengers can cause inflammation. When the immune system is working normally, the fight is over once the infection is gone. In RA some cytokine levels stay too high. This means that the fight and the inflammation go on and on. It is this ongoing inflammation that causes the symptoms of RA.
RA involves several types of cytokines:
- TNF: TNF is short for ‘tumor necrosis factor’. TNF is a cytokine that plays a large role in causing inflammation in RA.
- IL-1: IL-1 is short for ‘interleukin 1’. IL-1 is a cytokine and causes inflammation. People with RA generally have too much IL-1 in their systems.
- IL-6: IL-6 is short for ‘interleukin 6’. In RA, there is more IL-6 than any other cytokine in the lining of the joints. IL-6 is a common cause of inflammation in people with RA.