Pretend you are a scientist researching a new drug for liver disease. You have decided you would like to test your drug out on a very specific type of liver cell. So you take some cells you harvested from liver tissue and you grow them in colonies (which are very hard to keep alive), feed them complex nutrients to grow and thrive, and stabilize them in an environment conducive to their growth. Have you gone crazy yet? Well if you haven’t, imagine collecting the best growing cells, re-plating them and growing them again. Then picking the best cells and growing those cells again. And again. Then imagine watching the plates of those little cells you nursed to life die at the site of your new drug. Are you frustrated yet?
Stem cells could take all the guesswork and frustration out of growing cells. With the proper nutrients—or growth factors, stem cells have the potential to become the exact cell you select them to become. The growth factors send chemical signals to the cells that tell them exactly what type of cell they need to be. What a revolution!