Stem cells are cells which can become any cell type, like bone, muscle or hair. There are two types of stem cells, embryonic stem cells and adult stem cells1. Embryonic stem cells come from a fertilized egg, whereas adult stem cells are only found in some tissues to repair damage, like bone marrow1. Because stem cells can become any cell type, they are very important to science and medicine. For example, growing organs for transplant from the individual’s cells, this would resolve the problem of organ rejection2, however this is quite difficult. Furthermore, embryonic stem cells have ethical considerations, because they derive from fertilised human eggs3. Even though the egg would never develop in to a living person, many people oppose this research because they believe in life beginning at fertilization. So, while adult stem cells pose more challenges in producing a specific tissue, it is favourable to embryonic stem cells, but has only just become a feasible alternative4.
It has recently been announced that the first beating heart has been produced from adult stem cells5. This was achieved by using a mouse heart, removing the cells and using the remaining framework as a scaffold for the human stem cells to adhere. The cells are induced to develop into heart cells and after a few weeks it began to beat. This technology is a huge step forward, because the cells began to beat on their own. This technology could revolutionize heart transplants and replace pace makers by using a patch of healthy beating heart cells to repair the damage in the heart.
Being able to grow structured human tissue in this way is likely to revolutionize not just medicine but research as well, allowing for the accurate modelling of tissues for rare diseases. The latest advance was seen in the formation of brain tissue from stem cells6. Brain tissue is particularly difficult to obtain for some rare conditions as it cannot be removed before death and then often required the consent of the grieving family. Being able to successfully model the brain for specific diseases in this way means that drugs and treatments can be initially tested in culture to determine if they are targeting the desired cell types.
Stem cells can also resolve other problems, for example the ethical treatment of animals and producing animals for food. This month a burger was made solely from cow stem cells induced to become muscle tissue, this could hail the future of the meat industry7. Not only would it be ethical, as no cows would need to be slaughteres, but also it would address the environmental impact that meat production has, such as production of methane gas and increased demands for meat with reduced areas of countryside available for agriculture. Overall, it looks that stem cell technology is likely to revolutionize every aspect of our lives, with even the pope recognising the value and importance of adult stem cells in the future of our world3.