It is important that early in this discussion on prion diseases we differentiate between prion proteins and prions. Prion proteins (abbreviated PrP or PrPC for prion protein, cellular form) are normal proteins that are widely distributed throughout the body, but have their greatest concentration in the brain and nerve cells (this includes healthy people and animals). They are found in the membrane of these cells and appear to have some role in the transport of copper ions into cells, signal transduction, cell protection, and the formation of synapses.
