White blood cells which are also called leukocytes, are an important part of the immune system. There are five major types of white blood cells that are neutrophils, lymphocytes, eosinophils, monocytes and basophils.
These cells help fight infections by attacking bacteria, viruses, and germs that invade the body.
White blood cells originate in the bone marrow but circulate throughout the bloodstream.
An average normal range is between 3,500 and 10,500 white blood cells per microliter of blood (mcL)
