The immune system is your body's multi-layered defense system.
The immune system is your body's protective armor. The innate immune system is your first line of defense. It is made up of many cells including neutrophils and macrophages. If a threat is too big for the innate immune system to handle, it calls in the adaptive immune system's lymphocytes B cells and T cells. These cells, which stay at home in your lymph nodes until needed, have the ability to remember past threats and develop responses to specific infections. Using the immune system to prevent and treat cancer is a growing area of cancer research.
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