More on Mediums
More on Mediums
I’ve been remarking for a while now on developments that show the environment in which stem cells develop has an effect upon that development. Now a research team at the University of Florida has shown that when mouse embryonic stem cells were grown on four different types of medium in culture, they differentiated into different cell types. The press release says that a cell culture molecule called laminin “activates a common developmental pathway that is crucial for the generation and survival of particular types of brain cells.” The molecule has been used as a growth medium for stem cells in many experiments in which researchers did not know they were instructing the cells to differentiate in a particular way. The research gives clues to look at other molecules in the “niche” or extracellular matrix to see how the environment signals cells to become one kind of neural cell or another.
I’d like to see this experiment duplicated with bone marrow stem cells, since they can differentiate into several different forms of normal cells. It would be interesting to know what chemical signals they are picking up from their environment, or even how much adult stem cells are affected by their environment.
Now, on one hand it seems obvious that cells are influenced by their environment—we know they can be killed or mutated by particular toxins, radiation, and so on. But killing something is very different from transforming something. And when one begins to think of a stem cell as something other than a self-contained entity, all sorts of other possibilities begin to open up.