Illustration of natural killer T (NKT) cells (grey) attacking cancer cells (orange). NKT cells are lymphocytes (white blood cells) that act as part of the bodys innate (non-specific) immune response. They have receptors to detect and bind to molecules expressed on the surface of cancerous and infected cells. Once a cancerous cell is detected, NKT cells release cytotoxic granules containing enzymes and proteins that kill the cell.