In my Bioengineering class we’re now learning about something called tissue engineering. This is basically getting cells to grow into the tissues or organs that you want them too, usually outside of the body. Stem cells are the basis for tissue engineering because they are able to mature into different types of cells. Generally natural or synthetic materials are used to build a scaffold, this is a support structure for the stem cells to grow on. The scaffold should be the size and shape of the tissue that you are trying to grow and should also provide the stem cells with any signals that they need to divide and differentiate properly like growth hormones. The stem cells are then placed on or sometimes inside the scaffold and allowed time to grow. Ideally the stem cells will turn into the right kinds of mature cells and organize themselves just like they do in normal tissues. However, this is often very difficult to get right partly because we just don’t know that much about what causes stem cells to differentiate into different cells or how tissue development is normally regulated. Its really interesting to learn about all of the possibilities related to stem cells, there is the potential to save so many lives if we can figure out how to grow organs and tissues to replace those that are damaged.