a type of blood cell that functions as a defender against bacteria, viruses, fungi, and other foreign invaders. They are a vital component to the immune system.
A reduced amount of white blood cells (WBC) in the body makes a person more susceptible to infection. This can be a common side effect of chemotherapy
. People who have a low WBC count need to be especially cautious to avoid infection.
A high amount of white blood cells in the body can indicate the presence of an infection or also a blood disease, like leukemia