Monday, October 8. 2012
The man that envisioned a better way than destroying human embryos to get embryonic-like stem cells has won the Nobel Prize for Medicine. Dr. Shinya Yamanaka developed the technique to take an adult cell and reprogram it to an embryonic-like state as a way to avoid the destruction of human embryos. Dr. Yamanka's reprogrammed adult cells are called induced pluripotent stem cells (iPSCs) and have become a boon for the stem cell field allowing researchers to create new pluripotent stem cell lines for study without creating or destroying embryos.
In the New York Times, Dr. Yamanaka stated, “When I saw the embryo, I suddenly realized there was such a small difference between it and my daughters, I thought, we can’t keep destroying embryos for our research. There must be another way.”
Induced pluripotent stem cells are the perfect alternative to therapeutic cloning or somatic cell nuclear transfer (SCNT). SCNT creates a cloned embryo that would be destroyed for the pluripotent stem cells inside. Many scientists have called SCNT "the most promising" way to make pluripotent stem cells because it would create embryonic stem cells that are a genetic match to a patient. The problem with SCNT is that to make pluripotent stem cells that are a genetic match, human eggs are needed and a cloned embryo is created and destroyed. Induced pluripotent stem cells also creates pluripotent stem cells that are a genetic match to a patient because the reprogrammed adult cell is from the patient. But iPSCs technology does not require eggs or cloned embryos to do it.
And now iPSCs are coming into their own proving that ethics and science make good partners. Researchers are finding that iPSCs are great for creating models of disease. Previously, scientists would have to create a mouse or other animal that exhibited the symptoms of a human disease that they were interested in studying. Now they can take a skin cell from a person with a disease, reprogram that cell back to a pluripotent state, and then differentiate them into cells of interest whether they be neurons or fat cells. iPSCs can continue to grow in culture and be frozen giving researchers a nearly limitless supply of diseased cells to work on. This is especially useful in brain disorders because isolating neurons from the brain of a patient is dangerous.
The Scientist reports on the award shared with Dr. John Gurdon:
John B. Gurdon of the Gurdon Institute in Cambridge and Shinya Yamanaka of Kyoto University in Japan have won the 2012 Nobel Prize for Physiology or Medicine for finding that cells of an adult organism—once thought be terminally locked into their developed state—can start anew. The discoveries, awarded the prize this morning (October 8th) by The Nobel Assembly at Karolinska Institute in Stockholm, have ignited research in areas ranging from cloning to cancer treatment.
“Gurdon and Yamanaka fundamentally changed the way we all think about the specialized state of cells,” George Daley, director of the Stem Cell Transplantation Program at the Harvard Medical School, wrote in an email to The Scientist. “Collectively they taught us that the identity of a cell can be re-engineered—that an adult cell can be reverted to its embryonic state. This paradigm-shifting concept has opened up whole new avenues of research."
...Since the discovery, other scientists have generated iPS cells from humans—a feat which some argue reduces the need for controversial and difficult to acquire embryonic stem cells. These iPS cells allow researchers to study disease and development in the lab by, for example, generating disease models from the skin of patients with neurodegenerative disorders. The cells are also showing promise for cell replacement therapies to treat various illnesses.
“Induced pluripotent stem cells have already begun to revolutionize medicine,” Paul Fairchild, director of the Oxford Stem Cell Institute, said in an email. They provide “much-needed models of rare and complex disease states while providing sources of cells that may one day be used to replace those that are either worn out or compromised by degenerative diseases.”
|