Embryonic stem cells open medical research up to huge possibilities. These cells have the potential to be made into any type of cell by switching off and on certain genes in the DNA code. This ability can be used to form different tissues and even grow organs, providing new hope for the treatment of many medical conditions.
An exciting and rapidly developing prospect for stem cells is their potential as a cure for Type 1 diabetes. As yet, despite many decades of research, this condition still has no cure. Type 1 is not linked to obesity, unlike Type 2 and, scarily enough, the incidence is highest in teenagers and children and continues to rise.
This type of diabetes is an autoimmune disease because beta cells in the Islets of Langerhans in the pancreas are destroyed by the body’s own immune system. Therefore, a person is unable to produce the hormone insulin to regulate their blood glucose levels, leaving them responsible for taking over the role of their own pancreas. As you can imagine, this is a huge task for anyone in their day to day lives, and, if not managed properly by multiple daily injections of insulin and regular monitoring of blood glucose levels, long term complications of hyperglycaemia (high blood glucose) can occur, such as damage to heart, eyes, nerves, blood vessels and kidneys. However, even for people with good control of their blood glucose levels, treatment simply cannot match the precise function of the pancreas.
Therefore, stem cells could be the cure that can finally overcome this problem and all its associated complications, not to mention the freedom it could give to young people with diabetes from the regimented management of the condition. What’s more, hopes for the future are that embryonic stem cells could be made to be genetically identical to the recipient. This means that they would not face the same challenges as other treatments like islet cells, or whole pancreas transplants from donors, which pose a greater risk of rejection issues. There is also a distinct lack of donors; for instance, to obtain sufficient islet cells they must be taken from not one but two donors.
Be that as it may, using stem cells as a cure is, to put it lightly, far easier said than done. For one, the process of producing embryonic stem cells requires a high level of technical skill in order to manipulate minuscule, individual cells. To start, embryos must be carefully cultured for many months in special growth mediums, under certain conditions in the laboratory to prevent them differentiating into unwanted cell types. This is a very time-consuming and difficult process as each stem cell must be individually formed.
Following this, an ever more challenging difficulty arose in determining the very specific conditions and growth factors needed for the stem cells to differentiate into the insulin-producing beta cells desired. Genes, of which 24 have been identified, that keep the cell in a pluripotent state (one in which it is able to form any type of cell) must be, in effect, switched off. At the same time, a very specific set of genes must be expressed in order to form pancreatic beta cells.
In 2014 the Harvard Stem Cell Research team managed to replicate this process on a large scale, so that for the first time ever enough viable beta cells were formed to provide sufficient insulin to Type 1 sufferers when the body needs. So why, 3 years later, have we still not achieved a cure?
There are many factors, both scientific and ethical, halting the use of embryonic stem cells in some medical areas. However, for diabetes specifically the issue that remains is that, if transplanted into a sufferer, the new cells are at risk of attack by the body’s immune system. To overcome this final hurdle, methods are currently being developed to protect the cells, including semi-permeable encapsulation devices using different chemical compounds. For example, derivatives of alginate have been used by researchers at MIT, allowing the transplanted beta cells in mice to respond to blood glucose levels and produce the necessary insulin for 137 days.
It seems as though the use of stem cells is proving a real hope for Type 1 diabetes sufferers, and while we may still be a long way off widespread implementation of the cells as a cure, it is not by any means an unrealistic goal.
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