WBC

White Blood Cell (WBC) Count (also called leukocytes) is a measurement of your white blood cells, which are part of your immune system. They are a type of blood cell made in your bone marrow and found in your blood and lymph tissue (part of your immune system). If you are injured or get sick, the white blood cells travel through your bloodstream and tissues to where they are needed. There, they help your body fight off infections and other diseases. When you get sick, your body makes more white blood cells to fight the bacteria, viruses, or other foreign substances causing your illness. This increases your white blood count. Some diseases can cause your body to make fewer white blood cells than you need. This lowers your white blood count. Diseases can lower your white blood count include some types of cancer and HIV, a viral disease that attacks white blood cells. Certain medicines, including chemotherapy, also may lower the number of your white blood cells. There are five major types of white blood cells: Neutrophils, Lymphocytes, Monocytes, Eosinophils, and Basophils.