Today Dr Ghanem visited our school to give a talk on stem cell development to the Medical Society.
Stem Cell: An undifferentiated cell that is capable of giving rise to indefinitely more cells of the same type and from which certain other types of cell arise by differentiation.
Dr Ghanem began by talking about the first stages in the discovery of stem cells, he explained with awe about some of what he to be considered the greatest biologists in history such as Aristotle, who looked at stages of chicken embryo development, and Nicolaas Hartsoeker who invented the screw barrel simple microscope in 1695. He presented the idea that during this time the two opposing theories of stem cell research were developed: Preformation and Epigenisis.
Preformation- A theory popular in the 18th century that all parts of an organism exist completely formed in the germ cell and develop only by increasing in size.
Epigenisis- The theory that an individual is developed by successive differentiation of an unstructured egg rather than by a simple enlarging of a preformed entity.
In the late 19th century scientists such as Hans Drieson and Hans Spemann confirmed the theory of Epigenisis by experimenting on embryonic stem cells from mice, thus disproving Preformation.
Following this brief history Dr Ghanem then presented to us the fundamental questions:
-How is cell diversity generated and can we control this differentation?
The possibilities for this fields are huge and present amazing advances in regenerative medicine, with the possibilities of restoring cells destroyed from diseases like Alzheimer's and using stem cells to produce food and solve the global food crisis in countries especially LEDCs, where famine is a key issue.
Dr Ghanem showed us a PubMed citation illustrating just how huge the developments for stem cell research have been in the past 20 years with noble prize winners such as the 'Golden Triad' in 2007 and Sir John Gurdon and Dr Shinya Yamanaka in 2012 all recieving their awards for work on stem cells.
To understand the complexities of this topic Dr Ghanem then showed us the growth of two mice, one without the Pax6 gene, which codes for the developement of the eye. The mouse without this gene naturally had no eyes. Whilst this is simple to understand other genes such as the Sox2 are integrated into a huge number of areas and so cannot be simply described as coding for a single feature. He stated this was what was posing as the barrier to further development for scientists.
He presented this exciting and relatively new area of medicine showing us some of his own research into what 'switches' the coding in a stem cell to differentiate into any certain type of cell, comparing it to a goat in a tree which may choose to climb any one branch. But which branch the goat chooses is what Dr Ghanem has researched, which cell would be 'chosen' by any stem cell. He compared his efforts at 'cracking this code' to the efforts by Jean Francois Champollion to translate Hieroglyphics, which took 3 years.
Dr Ghanem's insight presented the exciting possibilities of stem cells for regenerative medicine, one day we may be able to simply produce new organs when our own deteriorate or malfunction, a possibility which could herald the turning of an age in medicine.
-Izzie
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