A results of a study conducted in Britain to project stem cell requirements for the establishment of a therapeutic stem cell bank has concluded that approximately 150 embryo-derived stem cell lines would be required to support the functioning on a daily basis.
Britain, South Korea and the United States represent countries where intensive stem cell research is being carried out. The world's first stem cell bank was established in Britain in the year 2004. Over the next two years, the amount of resources allocated for stem cell research in UK would be doubled to 100 million pounds, a part of which would be used to support functioning of the stem cell bank.
Stem cell banks procure stem cells, store and distribute it for research purposes aimed at treatment of human diseases. This mode of treatment is called stem-cell therapy. Although the effective utilization of this form of therapy cannot be accomplished immediately, results of clinical trials conducted on animal models seem promising.
Currently, there is an increasing focus on stem cell therapy for treatment of neurodegenerative disorders (Parkinson's disease, Alzheimer's disease), cancer, diabetes and spinal cord injuries. Furthermore, it is estimated that a large number of stem cell lines would be required to match the recipient demand in most of the cases.
It has been estimated that a one in five recipients would have a good match if the number of potential donors were increased to 150. It would also be sufficient to provide a modest match for about 90% and an intermediate tissue match for about 50 to 70% of patients. Surprisingly, a sub-set of stem cells from 10 human embryos have been identified that could theoretically provide a very good match for about 38% of recipients.
Similar to human organ transplantation, the embryonic stem cells from a therapeutic bank would have to be tested for tissue compatibility to minimise chances of rejection and eliminate need for immunosuppressant drugs. Unlike the one to one donor - patient liver, cardiac and renal transplants being performed currently, a single stem cell line could be exploited to benefit multiple recipients.
Despite potential advantages of stem cell therapy, much progress has not been made due to ethical concerns regarding the source of stem cells. Currently, the stem cells are obtained from spare in-vitro fertilization (IVF) embryos, after a written informed consent has been obtained from potential parents.