Now, the cytotoxic T cell has a special membrane protein known as the death activator. And so what happens is, when they actually bind on the outside, that will initiate some type of internal process that will activate a cast based protein. But this cast based protein is slightly different than caspase nine. We call it caspase eight, but it's still protease. And what that means is once we activate the cat space nine inside the cell, that cat space I'm sorry, cat space eight. Once we activate the cat space eight, it will go on to basically destroy the organelles and the structures inside the cell as well as the DNA inside the nucleus of that cell.