When we talk about stem cells, we are actually talking about a complicated series of things, including adult stem cells which are largely cells devoted to replacing individual tissues like blood elements or liver or even the brain.

Adult stem cells tend not to form tumors.

Stem cells are probably going to be extremely useful.

Throughout our lifetimes, we are constantly regenerating new brain cells in the hippocampus, a process called neurogenesis. New stem cells are constantly being born in the hippocampus that ultimately differentiate into fully functional neurons.

We believe that these types of cells are actually more primitive and more flexible than the adult stem cells that would be found in bone marrow, ... They're much younger. They're more robust.

This work shows that stem cells can be used as drug delivery vehicles in the brain.