Lowering High White Blood Cell Counts with Leukapheresis
Leukapheresis is a procedure to separate and collect white blood cells from the blood. Leukapheresis may be used as a treatment for certain types of leukemia or as the first step of chimeric antigen receptor (CAR) T-cell therapy.
Why is leukapheresis done?
When there are too many leukemic cells in the blood, it can cause problems with normal circulation and can crowd out healthy cells. While chemotherapy is the standard treatment for leukemia and can help reduce the number of leukemic cells, it can take several days after the first treatment for this effect to occur. Leukapheresis may be used as a temporary treatment prior to chemotherapy to lower the number of leukemic cells.1
In people who are receiving CAR T-cell therapy, leukapheresis is used to remove the patient's T-cells (a type of white blood cell). These T-cells are modified with specific receptors on their surface, referred to as chimeric antigen receptors (CAR). These receptors allow the T-cells to recognize and attach to a specific protein found on the blood cancer cells. The modified T-cells are then replicated in the laboratory to create hundreds of millions of copies. The engineered T-cells are then infused into the patient, where they find and kill the cancer cells in the body.2
How leukapheresis is performed
During the leukapheresis procedure, the patient is lying down or in a reclined position. Generally, two intravenous (IV) lines are used: one line removes the blood and one line will return the blood cells and plasma that are not collected. In some people, only one large catheter may be used, called a central line. The blood that is removed from the body goes through a machine, called an apheresis machine, where the white blood cells are separated out and collected. The remaining blood is returned back to the patient. The procedure can take several hours to complete.1,3
Potential risks of leukapheresis
Leukapheresis is generally a safe procedure. Some people experience numbness and tingling in the hands, feet, or mouth, or painful muscle spasms. These symptoms are typically caused by a lowering of the amount of calcium in the blood and can be treated with calcium, which may be given through an IV.1,4
Patients should talk to their doctor if they have any questions, or if they have questions regarding their leukapheresis procedure. Before undergoing leukapheresis, patients should tell their doctor about all their health conditions, as well as any medications (prescription and over-the-counter), herbal supplements, and vitamins they are taking.