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(from http://biotechniques.com/news/Japan...bcf133163-BTNWeekly_09032009&utm_medium=email)
Shinya Yamanaka, director of the Center for iPS Cell Research and Application at Kyoto University in Japan, spoke about his work with induced pluripotent stem (iPS) cells on Jan. 14 at the National Institutes of Health (NIH), as part of the institute’s Wednesday Afternoon Lecture series.
Shinya Yamanaka, M.D., Ph.D., presented a Wednesday Afternoon Lecture on January 14, 2010. In his address at the NIH, Yamanaka described how his work with iPS cells began in 2000 when he accepted a position at Japan’s Institute of Science and Technology. He developed the hypothesis that somatic cells, like skin fibroblasts, could be reprogrammed to achieve the pluripotent abilities of embryonic stem cells. He spent the next four years researching genetic transcription factors responsible for pluripotency in embryonic stem cells. In 2005, he moved to Kyoto University after narrowing his search to 24 possible genes.
“We could not simply try all of the combinations. It was too much even for us,” said Yamanaka. Instead, Yamanaka’s team tested a mixture of all 24 factors to induce pluripotency, then removed them one by one to discern which ones were responsible. This method enabled the researchers to discover that Oct3/4, Klf4, Sox2, and c-Myc have the ability to induce pluripotency in differentiated cells. The groundbreaking results were published in Nov. 2007 in Cell.
Currently, Yamanaka is collaborating with researchers from Keio University in Tokyo to study iPS cells as a treatment for spinal cord injuries. “If we use patient-specific iPS cells in medicine, we can avoid ethical issues regarding the use of embryos, and we can avoid immune rejection. But this is very expensive and time consuming,” said Yamanaka. “In the case of spinal cord injuries, we have to transplant the neural cells within 7 to 10 days after the injury. But it takes at least three months to make transplantable iPS cells, so we would never make it.”
Shinya Yamanaka , MD, PhD, presented a Wednesday Afternoon Lecture on January 14, 2010. Source: NIH. To meet this challenge, Yamanaka told his audience that he hopes to create an iPS cell bank that would mimic the setup of current blood banks. But he expressed concern that he might not be able to raise the necessary funding. “We have a new Japanese government, and the new government is not so friendly to scientists. So we are having a little bit of trouble,” said Yamanaka.
The improvement and refinement of reprogramming techniques is just beginning, according to Yamanaka. “In order to realize iPS cell–based therapy, we need to establish uniform and complete reprogramming; we need to determine the best origin of human iPS cells, the best induction method, and the best evaluation method before we apply the technology,” he said.
The Wednesday Afternoon Lecture series has been a part of the NIH for over 15 years. During each speaker’s visit they meet with a group of 11 NIH post doctoral researchers and graduate students, in addition to their lecture. Past speakers include Rudolph Jaenisch, an induced pluripotent stem cell researcher at the Whitehead Institute, and National Medal of Science winner Elaine Fuchs, a stem cell researcher at the Rockefeller University.
Shinya Yamanaka, director of the Center for iPS Cell Research and Application at Kyoto University in Japan, spoke about his work with induced pluripotent stem (iPS) cells on Jan. 14 at the National Institutes of Health (NIH), as part of the institute’s Wednesday Afternoon Lecture series.
Shinya Yamanaka, M.D., Ph.D., presented a Wednesday Afternoon Lecture on January 14, 2010. In his address at the NIH, Yamanaka described how his work with iPS cells began in 2000 when he accepted a position at Japan’s Institute of Science and Technology. He developed the hypothesis that somatic cells, like skin fibroblasts, could be reprogrammed to achieve the pluripotent abilities of embryonic stem cells. He spent the next four years researching genetic transcription factors responsible for pluripotency in embryonic stem cells. In 2005, he moved to Kyoto University after narrowing his search to 24 possible genes.
“We could not simply try all of the combinations. It was too much even for us,” said Yamanaka. Instead, Yamanaka’s team tested a mixture of all 24 factors to induce pluripotency, then removed them one by one to discern which ones were responsible. This method enabled the researchers to discover that Oct3/4, Klf4, Sox2, and c-Myc have the ability to induce pluripotency in differentiated cells. The groundbreaking results were published in Nov. 2007 in Cell.
Currently, Yamanaka is collaborating with researchers from Keio University in Tokyo to study iPS cells as a treatment for spinal cord injuries. “If we use patient-specific iPS cells in medicine, we can avoid ethical issues regarding the use of embryos, and we can avoid immune rejection. But this is very expensive and time consuming,” said Yamanaka. “In the case of spinal cord injuries, we have to transplant the neural cells within 7 to 10 days after the injury. But it takes at least three months to make transplantable iPS cells, so we would never make it.”
Shinya Yamanaka , MD, PhD, presented a Wednesday Afternoon Lecture on January 14, 2010. Source: NIH. To meet this challenge, Yamanaka told his audience that he hopes to create an iPS cell bank that would mimic the setup of current blood banks. But he expressed concern that he might not be able to raise the necessary funding. “We have a new Japanese government, and the new government is not so friendly to scientists. So we are having a little bit of trouble,” said Yamanaka.
The improvement and refinement of reprogramming techniques is just beginning, according to Yamanaka. “In order to realize iPS cell–based therapy, we need to establish uniform and complete reprogramming; we need to determine the best origin of human iPS cells, the best induction method, and the best evaluation method before we apply the technology,” he said.
The Wednesday Afternoon Lecture series has been a part of the NIH for over 15 years. During each speaker’s visit they meet with a group of 11 NIH post doctoral researchers and graduate students, in addition to their lecture. Past speakers include Rudolph Jaenisch, an induced pluripotent stem cell researcher at the Whitehead Institute, and National Medal of Science winner Elaine Fuchs, a stem cell researcher at the Rockefeller University.
