A type of adult stem cell is now proving itself more versatile for research and therapies thanks to revolutionary 3D experiments. These cells have already shown great promise for repairing damaged bone and cartilage but until now have been fairly limited in the types of cells they can form in the laboratory.
Dr Paul Genever is working to grow mesenchymal stem cells (MSCs) – currently one of the leading candidates to be used in stem cell therapies – as tiny spheres. Under these conditions MSCs show potential to become a variety of different cell types including, possibly, the early precursors to heart muscle cells.
“In the past we’ve grown MSCs in 2D layers in the lab and they are only really strongly inclined to become bone, fat or cartilage – they are very useful for research and therapy, but in both cases would largely be limited to these three cell types.
“Our 3D technique aims to recreate the nutrients, oxygen levels and mechanical forces that these cells would normally experience inside our bodies. By growing the cells as 3D spheres of microscopic size instead of in a 2D layer, they specialise their roles more rapidly and more completely and also appear to be able to become a greater range of cell types. This shows that they are quite a bit more versatile than we thought and so are a very exciting prospect for the use of these cells in therapies.”
The spheres used are made of aggregates of MSCs and are tiny, measuring only 200-300 micrometers across – about half the size of a dust mite. Within these spheres it is possible to monitor the effects of interactions between several cells and between cells and other supporting structures. The MSCs can also be combined with other types of cells that they would usually be associated with such as endothelial cells, which are found on the surfaces of blood vessels.