White blood cells have the function of detecting and destroying foreign substances that cause disease in the blood throughout the body. Blood test shows the condition and number of white blood cells in the body, thereby detecting abnormalities in white blood cells.

White blood cells are part of the immune system and are responsible for fighting infections and foreign substances in the blood. White blood cells are divided into three main types: granulocytes, monocytes, and lymphocytes.

Leukocyte therapy is an emergency treatment that separates peripheral leukocytes from the circulatory system (usually malignant blood cells) using a specialized cell extractor. The goal of this approach is to rapidly reduce leukocytes in the blood to limit the risk of hyperviscosity and embolism.