Stem cell growth on carbon-nanotube-based scaffolds

Scientists often wish to grow human cells in test-tubes, indeed ultimately they hope to take a special type of cell, called a stem cell, and cause them to grow into complete organs completely outside of the body. These organs could then be used to replace failed organs and so save lives. However, this is very difficult and one of the reasons for this is that our cells have evolved to grow inside our body where the cells are within and bind to a complex matrix which not only holds them together (and so prevents our body disintegrating into a large blob of cells) but also provides them with cues, e.g., grow here, don't grow there, become a nerve cell, etc. Thus, if we want to grow cells in test-tubes we need to produce surfaces for the cells to grow on that mimic the rough, elastic surfaces found within the body. In this proposal we want to acquire the skills to grow stem cells on surfaces that we already know how to make.We are already using a unique form of carbon, called carbon nanotubes to make surfaces that are as rough as some of the surfaces inside cells. Carbon nanotubes are long tubes of carbon that are only a few billionths of a metre across (a human hair is more than a 1000 times wider) but are much longer than this, hence the name tube. Also, scientists have shown that the roughness of surfaces affect how cells grow on them. Thus we have the surfaces for the cells but lack the special expertise in growing the cells. We will work with a group of scientists in California who specialise in stem cells, and learn from them. In return they will be able to use our nanotube scaffolds to grow their cells. The new skills we will learn will not enable us to grow complete organs, but they will allow us to both better understand how growing stem cells interact with the surface they are growing on, and to improve our ability to grow these cells. For example, as we can control the roughness of our surfaces we will able to see whether there is an optimal roughness for cell growth, such that the cells grow more slowly on both smoother and rougher surfaces.