Animals and the Nobel Prize
Last week, the invaluable contributions made to modern medicine by two pairs of scientists were recognised in the awarding of the Nobel Prize for Physiology or Medicine to Sir John Gurdon and Shinya Yamanaka and the Prize for Chemistry to Robert Lefkowitz and Brian Kobilka. Like all advances in medicine, animals were central to the research of these scientists that has changed the way we approach the development of new treatments today.
Over the last 40 years, every Nobel Prize in Physiology or Medicine bar one (1983 - Barbara McClintock for her plant genetics research) has depended on work using animals.
This year, Sir John Gurdon and Shinya Yamanaka were awarded the Prize for Physiology or Medicine for their work on reprogramming mature cells into stem cells, based on research with frogs and mice.
For much of the 20th century, scientists believed that the path of specialisation that cells go down as they form the tissues and organs of the body was an irreversible one. Scientists didn’t know if they contained the right genes or whether those genes were forever inactivated. In 1962, John Gurdon radically changed this view by showing that the DNA-containing nucleus of a cell taken from the intestinal lining of a frog, transplanted into a frog’s egg could go on to produce a healthy tadpole. This demonstrated that the DNA of a fully-developed cell of the intestines contains all the genes required to produce any cell in the body and that they could be reactivated.
In Gurdon’s experiments, it was the transplantation of the DNA-containing nucleus into an egg that reactivated the genes, allowing the production of a whole new animal. In 2006, Shinya Yamanaka went a step further by proving that the introduction of a small set of gene-activating proteins called transcription factors into a whole cell could revert it back into a cell that had the capacity to form any other cell type in the body. The cells had effectively been reprogrammed and were called induced pluripotent stem cells (iPSCs). This breakthrough meant that potentially almost any human cell could be used to create a new organ or even a new person. In Yamanaka’s original studies he created mice that contained tissues formed from the reprogrammed cells and in later experiments produced the first human iPSCs.
The ability to grow new organs from a patient’s own cells holds great promise for future therapies. Crucially, because it is the patient’s own cells, the danger of immune rejection suffered in so many transplant operations is not an issue. One day scientists hope to be able to repair hearts damaged by heart attack and grow new neurons to repair brains ravaged by Alzheimer’s Disease. Reprogrammed human cells are also reducing the number of animals needed for medical research and the testing of new drugs by allowing the production of cells and tissues, where before animals were the only source.
The 2012 Nobel Prize for Chemistry was awarded to Robert Lefkowitz and Brian Kobilka for their work in uncovering the mechanisms of cellular signalling through their work on a class of receptors found on the surface of cells called G-protein coupled receptors. They first developed techniques to purify the receptor complexes from extracts of frog and hamster tissues. They were then able to measure the activity of the receptors and study their molecular structures to discover how they bind to hormones or medicines at the cell surface and then transmit a signal into the cell. Lefkowitz and Kobilka produced detailed structural images of the receptors now common in undergraduate biology textbooks the world over.
About half of all today’s medications act through G-protein coupled receptors, morphine being perhaps the most famous. The work of Lefkowitz and Kobilka has been crucial to understanding how medicines work and has allowed the design of better medicines with fewer side effects over the years. Since their discovery, the pair have both continued to uncover the secrets of cellular signalling using genetically modified mice alongside non-animal methods.
This year’s Nobel awards have once again highlighted the central role of animals in some of the greatest scientific discoveries of modern medicine. There is no doubt that without this research we would not be lucky enough to have the treatments and cures that we enjoy today.
Read more about the research behind the prizes here: