Photopheresis is a process which extracts and separates a patient’s white blood cells from the blood and exposes the cells to ultraviolet light and a photoactive drug. The modified white blood cells are returned to the body to potentially stimulate a positive therapeutic response.
This treatment serves as a type of "vaccination" against disease producing T-cells. Photopheresis is used to treat cutaneous T-cell lymphoma, Graft vs. Host Disease, and solid organ transplant rejection.