Medical advancement has proved cell transformation more convenient than predicted. Fibroblasts, a type of skin cells can be converted into neurons with just some simple twists according to a recent report published. The transformation process did earlier rely on embryonic stem cells as differentiation of adult cells was thought too complex but not any longer.
An online publication of Journal of Nature 27 January 2009 on “Direct conversion of fibroblasts to functional neurons by defined factors” reported ease of transforming skin cells into neurons. It can practically become easy to replace neurons in the future. Producing brain cells as of skin cells will make the cells genetically suitable for the patient and therefore avoid immune rejection. This can probably be a possible cure towards list of neurodegenerative diseases such as Parkinson’s.
Marius Wernig, leader of the research as well as a biologist at the institute of Stem Cell Biology and Regenerative Medicine at Stanford described the progress as amazing. The fact that, by tweaking a few factors, cell fates will slowly start to show neuronal characteristics is remarkable.
It was only three years ago that researchers began to try to transform adult cells into an embryonic state through the use of four genetic factors. The finding on these so called induced pluripotent stem(iPS) cells made global head news. The IPS cells have the potential to be changed into any somatic cells in our body, having thus a great possibility for tissue replacement therapies. Now cellular research is going further by making it possible to convert adult cells into any other type of cells.
A Harvard Research, 2008, led by Doug “Melton”, “Qiao Zhou” and their colleagues proved that it was feasible to changing a specific pancreatic cell into other types of cells. This could well be considered as a possible treatment for diabetes. However, this research showing that skin cells can transform into neurons is more intriguing. Given, the fact that neurons cells and skin cells do at an early stage of the embryonic development differentiate, yet they can be transformed.
Formulating the Equation
The whole experiment started by selecting 20 genes found specifically in the brain that plays a fundamental contribution in neural development. Moreover, these 20 genes had transcription factors which associated it to DNA as well as to regulate expression of other genes. Different viruses were used to extract these gene and they were thereafter placed in a dish where skin cells were grown. It was observed that a particular gene had the potential to convert the skin cells into apparently immature neurons. All the genes were tested in combination with the one being active. It was seen that blending 3 particular genes together made skin cell conversion into neuron cells fast and efficient.
The new cells that are developed have all the features of neurons. They do also appear to have capacity to become electrically active as normal neurons in brain. According to, Zhou, this is an erratic advancement as few scientists have ever believed that such efficient transformation of cells were possible.
Direct or Indirect Conversion – Which is easier?
This process of converting cells, if every applicable to human will open an unexplored arena. According to Wernig’s team, bypassing iPS cell process which is highly complex makes it much easier to handle cell transformation.
It is still premature to discharge “iPS cells”, as each method can have its various benefits. For instance, iPS cells can be automatically produced and can make available in huge quantities according to Sheng Ding, biologist not involved in the research from Scripps Research Institute, La Jolla, CA.
There is still much uncertainty. The transformation process is ambiguous. It is also a fact that genetically identical cells might indeed have completely varied identities due to epigenetics. Epigentics is practically the mechanism used by cells to store their DNA. This packaging controls active and inactive cells which can transform into any other type of somatic cell such as brain, skin and heat cells.
According Zhou, it is necessary to understand the underlining epigenetic and molecular structure to be able to grab the reprogramming recipe better. It will also increase our capability to intelligently manipulate the system.
It can eventually be the case that direct reprogramming of cells is even more complex than iPS cells. When adult cells are turned into an embryonic state the epigenetic markers can simply be removed. However, in direct transformation, the epigenetic markers must be handled properly. There are many marks that must be removed and other that will have to be left standby, making the process highly intricate.
Human therapies using cell transformation can only be used after an amalgamation of chemical mixture has been procreated to avoid cancerous cells. Genetically engineered cells have already been produced through iPS cells.
Wenrnig’s research team will now try the same experiment on a mouse with Parkinson’s disease.
The history of cells is now to be reconsidered. It has since long been considered that epigenetic mortification of cells were stable. The dolly sheep and iPS cells have made facts irrefutable. Cells can take various functions irrespective of their actual nature and research is proving it over the field.
Source: Technology Review
Fri, Feb 5, 2010
Nanotechnology, Stem cells