Human embryonic stem cell (hESC) treatment is believed by many scientists to be at the forefront of medical advancement. hESCs may be moulded into any of the human body’s specialised cells, and have the potential to treat a variety of human conditions. A recent report documents the use of hESC to partially cure blindness in a number of individuals. The subject of human stem cells as a treatment has been ethically challenging, however, the productive effects of potential treatment are gradually becoming evident.
hESCs have the ability to become any of the 200 human tissue types, giving them a unique property for medical treatment. Embryonic cells with this capacity are known as pluripotent. In a recent study by Robert Lanza and his team at Advanced Cell Technology in Marlborough, Massachusetts, 18 individuals with eye conditions received hESC treatment. The treatment used pluripotent hESCs to create retinal pigment epithelial cells. These epithelial cells maintain the health of the rods and cones in a person’s eyes. Individuals with age-related macular degeneration and Stargardt’s macular dystrophy are faced with difficulties when it comes to maintaining the health of these cells.
These eighteen individuals had retinal pigment epithelial cells injected into their eyes. Ten of the eighteen individuals’ eyes showed improvement, whilst the other eight patients’ eyes stabilised. Lanza believes that the improvements, which were a surprise success for the team, may be due to the new cells encouraging rods and cells to resume their function. The quality of life for the individuals involved in Lanza’s trial has improved. One male patient has been able to take up horse riding again due to the improvements. Another patient is able to read the top four lines of a typical eye test, compared to before the procedure, where she was challenged to read the top line. Some patients regained the ability to see colour. This study has given researchers the confidence that the procedure is both effective and safe on a medium to long-term scale. Advanced Cell Technology plans to expand the treatment and trial 100 people with Stargardt’s macular syndrome, followed by a further 100 with macular degeneration.
The applications for hESCs are potentially important for the future of medical treatment as a whole. hESCs are to be used in other studies to help treat both type 1 diabetes and heart conditions. In France, six individuals are to receive a patch of heart cells, derived from hESCs, in order to treat a heart condition. The patch may help regenerate heart muscle; this has been successful in trial experiments with monkeys. Twenty per cent of the affected muscle area was regenerated within two months in these trials. Researchers predict that similar results may occur in the human trials.
Similarly, in the US forty individuals with type 1 diabetes are to receive pancreatic cells. These cells are thought to mature and produce the hormone insulin. Previous work in cardiac and pancreatic cells has used adult stem cells. However, when using adult stem cells it is difficult to guarantee which cells they may develop into. Embryonic stem cells, on the other hand, may be more easily moulded into specific tissue types. Researchers believe that the studies using hESCs should show greater success rates. The French and American studies may monitor the success and safety of the procedure, as with Lanza’s eye study.
Human embryonic stem cells have shown success and safety in treating blindness in a number of individuals. Further studies on type 1diabetes and heart conditions are poised to show similar results. The use of hESC to improve people’s quality of life may hold the solution to other important conditions.
How else may stem cell therapy help improve the quality of people’s lives?