These proteins end up killing off many of the nerve cells, which eventually degenerates the mental capability and the brain function of that particular individual. And patients with these conditions develop a sponge like brain that basically resembles a sponge in the sense that it contains many holes. And those holes come from the fact that these aggregate molecules kill off the different types of cells, different types of nerve cells inside our brain. So we see that usually the misfolding of a protein doesn't actually do much because our body is capable of denaturing and breaking down that misfolded protein or folding it correctly into that correct shape. But sometimes we get something called a Pryon, and these are very, very dangerous infectious agents. So up until recently, we thought that only bacterial cells and viruses are capable of infecting our bodies and the bodies of other animals.