Stanford Report, February 20, 2002
By AMY ADAMS
Knowing that your life's work is central to one of the hottest issues of the day makes for a happy 70th birthday. Leonard Herzenberg, professor of genetics, celebrated on Friday with a symposium dedicated to stem cell research – and to the technology he developed that makes much of stem cell research possible.Some excitement about progress in the field was diminished, however, by pending regulations that could hinder stem cell research and make life-saving technologies that arise from the research unavailable in the United States. In an opening address, Paul Berg, professor emeritus of cancer research, said of Herzenberg's work, "The development of this new technology allowed people to do things they could never do before."
Herzenberg developed the flow cytometer (FACS) device, which researchers use to quickly sort cells into subsets according to the proteins they contain. "Everything you hear today will demonstrate the power of FACS," Berg predicted at the start of the symposium.
In addition to toasting the guest of honor, Berg's opening address highlighted the issues facing stem cell research.
A bill before the Senate would not only make human cloning illegal, would ban all forms of human nuclear transfer – the technology that makes cloning possible – for use in generating research stem cells, and would ban treatments that arise from such technology from being available in the United States.
These discoveries could include treatment for diabetes, Alzheimer's disease and Parkinson's disease. "They are taking legitimate research and criminalizing it," Berg said.
Berg equates the furor over stem cell research to a similar moral quandary the government faced in regulating recombinant DNA research – which is now a common research technique and produces, among other things, the insulin that diabetics need to survive. And, as he did for that issue, Berg has been working to help those in government understand the power of new research. "I'm educating the uneducable, getting the point across to people who should know better," he said.
Other speakers at the symposium demonstrated the power of stem cells in understanding and treating disease.
Helen Blau, director of the Baxter laboratory for Genetic Pharmacology, has found that stem cells in the blood of mice integrate into tissues of the body and take over for damaged cells.
"If you hurt yourself playing softball or rugby, these cells come in and repair injury," she said. She also found stem cells taking over for neurons in a region of the brain that has a high turnover of cells.
Blau is looking for a way to distinguish stem cells that go on to form different types of tissues. By understanding this process, she said, researchers could learn how to induce stem cells to take over for dying cells. This application could be of particular use in the brains of Alzheimer's patients.
Stem cells created through nuclear transfer may also provide a model for studying disease, said Irving Weissman, the Karel and Avice Beekhuis professor of Cancer Biology and Professor, by courtesy of biological sciences.
By taking a nucleus from a breast tumor cell, for example, and transferring that nucleus into an egg, researchers could get a detailed understanding of the genetics and biology of breast cancer, possibly leading to new forms of treatment. "You might learn an awful lot about the cause and effect nature of that disease," Weissman said.
Although the stem cell controversy focuses on cells that come from either human fetuses or are made through nuclear transfer, both Weissman and Blau work on stem cells found in the blood of adults.
These adult cells are not as flexible as embryonic stem cells, but they do have therapy-producing potential and -- an important point -- raise no moral red flags.
Weissman and Blau pointed out the potential of using adult stem cells to learn how cells develop into a particular cell type.
"As the cells move through development they express certain genes," Weissman said. "You can develop an assay for that." Such an assay – combined with Herzenberg's FACS – could help researchers isolate particular types of cells that may be useful in treating disease.
However, Weissman cautioned that although adult stem cells are a powerful tool, they can't replace embryonic stem cells for many types of research. "They aren't a substitute," he said.
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